NC0024945_Permit Issuance_20050429

NPDES DOCUHENT SCANNINO COVER SHEET
NPDES Permit:
NC0024945
Irwin Creek WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
Draft Permit
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
April 29, 2005
This document is printed on reuse paper - ignore arty
content on the i ' Terse side

Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Alan W. Klimek, P.E. Director
Division of Water Quality
April 29, 2005
Ms. Jacqueline Jarrell
Charlotte Mecklenburg Utilities
5100 Brookshire Boulevard
Charlotte, North Carolina 28216
Subject: NPDES Permit Issuance
Permit NC0024945
CMU - Irwin Creek WWI?
Mecklenburg County
Dear Ms. Jarrell:
Division personnel have reviewed and approved your application for issuance of the
subject permit. Accordingly, we are forwarding the attached NPDES discharge permit. This
permit is issued pursuant to the requirements of North Carolina General Statute 143-215.1
and the Memorandum of Agreement between North Carolina and the U.S. Environmental
Protection Agency dated May 9, 1994 (or as subsequently amended.)
The permit authorizes Charlotte Mecklenburg Utilities to discharge up to 15 MGD of
treated wastewater to Irwin Creek, a class C water in the Catawba River Basin. The permit
includes discharge requirements for flow, biochemical oxygen demand (BOD), total suspended
solids (TSS), ammonia, fecal coliform bacteria, total residual chlorine, total nitrogen, total
phosphorus, chromium, cyanide, mercury, nickel, copper , zinc and pH.
Please note the following changes from the proposed final permit of September 1, 2003:
• Based on additional review of the reasonable potential analysis, the effluent limit and
monitoring requirement for silver has been removed from the NPDES permit. All the
reported effluent values are below detection, therefore no potential for exceeding the State
action level exists. Silver will continue to be monitored during the long term monitoring plan
of the pretreatment program for the Irwin Creek treatment facility.
• There have been revisions to the total copper and total zinc limits that are included in this
permit for the protection of South Carolina waters.. Upon receipt of additional information
from CMU and South Carolina Department of Health and Environmental Control (SCDHEC),
DWQ is including the permit limits that have been mutually agreed upon. Attached is a
summary document that illustrates how the limits were derived. The weekly average and
daily maximum limitations for copper are 21 µg/L and 31 µg/L, respectively. The daily
maximum limit for zinc is 317 µg/L.
• If CMU decides to develop site -specific standards, the proposed course of action should be
consistent with "Interim Guidance on Determination and Use of Water -Effect Ratios for
Metals" EPA 823-B-94-001, February, 1994. As previously mentioned, these limitations
have been implemented based on protection of South Carolina waters and standards. South
Carolina standards allow for NPDES limit development based on the dissolved fractions for
North Carolina Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 Phone [phone] Customer Service
Internet h2o.enr.state.nc.us
512 N. Salisbury St. Raleigh, NC 27604
FAX [phone]
N°`aturalll/ Caro ina
An Equal Opportunity/Affirmative Action Employer-50% Recycled/10% Post Consumer Paper

1,
Permit NC0024945
copper and zinc. Since the limits specified in this permit are based on "total recoverable",
CMU may request limits for copper and zinc based on the total dissolved fraction.
• A schedule for compliance for the daily maximum fecal coliform limit has been granted and
must be met by October 1, 2005.
• The site for downstream monitoring station LSC3 has been changed from Route 521 to
Highway 51 to allow safe access for CMU monitoring personnel per the October 18, 2004
permit minor modification.
• The draft permit contained monthly average limits for ammonia. In addition to the monthly
average limit proposed in the draft permit, the final permit contains a summer 3.6 mg/L
weekly average ammonia limit and a winter 6.9 mg/L weekly average ammonia limit. The
weekly average requirements are necessary to comply with federal regulations.
• This permit will expire on May 31, 2010 and will place the CMU permit back on schedule in
the Catawba River Basin. The expiration date will allow the milestone date stipulated in the
2002 Settlement Agreement to occur within the term of this permit.
The following changes were previously noted in the September 1, 2003 final proposed permit:
• Sampling type for mercury has been changed from composite to grab.
• Based on comments received during the public comment period, the total phosphorus
condition has been modified to reflect the requirements of the 2002 Settlement Agreement.
• Since outfall 002 no longer exists, it has been removed from the permit.
• Based on comments received during the public comment period, a fecal coliform daily
maximum limit of 1000/100 ml has been added to the permit. The new limit is consistent
with the EPA approved Fecal Coliform Total Maximum Daily Load (TMDL) for Irwin,
McAlpine, Little Sugar, and Sugar Creek Watersheds. This TMDL was developed by the
Mecklenburg County Department of Environmental Protection with active participation by
the South Carolina Department of Health and Environmental Control (SC DHEC), North
Carolina Division of Water Quality (NC DWQ), Charlotte Mecklenburg Utilities (CMU) and
United States Geological Survey (USGS). As previously noted, this limit will become effective
on October 1, 2005.
• Based on comments received during the public comment period, the summertime instream
monitoring frequency has been modified to weekly. The draft permit did not reflect the
modifications to the monitoring frequency implemented in 2001. Therefore, the summertime
instream monitoring frequencies were modified to be consistent with this modification.
• Based on comments received during the public comment period, the footnotes have been
corrected establishing the practical quantitation limits and reporting requirements for
cyanide. The permit requires that the permittee use analytical methods capable of
quantifying the pollutants below the permit discharge requirements and all data generated
must be reported down to the minimum detection or lower reporting level of the procedure.
If no approved methods are determined capable of achieving minimum detection and
reporting levels below permit discharge requirements, then the most sensitive (method with
the lowest possible detection and reporting level) approved method must be used.
• Based on comments received during the public comment period, compliance with the total
residual chlorine limit will be based on a daily average.

Permit NC0024945
• In response to the new NPDES municipal application data requirements, DWQ is reinstating
annual effluent pollutant scans into municipal permits. Special Condition A.(10.) of this
permit details this requirement. Be advised that pollutant scan data are required to be
submitted on the Discharge Monitoring Report Form for the appropriate month. Upon
renewal of this permit, CMU should use this data in completing the application.
In addition to the effluent pollutant scan monitoring requirements stipulated in the
new NPDES municipal applications, facilities discharging greater than 1 MGD or having a
pretreatment program are required to conduct additional whole effluent toxicity monitoring
prior to submittal of the permit renewal application. This additional toxicity monitoring must
be completed on a second species (one other than the species specified in the permit) and
include four test either quarterly within one year of application submittal or annually within
four and one-half years of application submittal. Though this monitoring is not a condition
for this permit, the facility should make plans to conduct this additional monitoring.
If any parts, measurement frequencies or sampling requirements contained in this
permit are unacceptable to you, you have the right to an adjudicatory hearing upon written
request within thirty (30) days following receipt of this letter. This request must be in the
form of a written petition, conforming to Chapter 150B of the North Carolina General
Statutes, and filed with the office of Administrative Hearings, 6714 Mail Service Center,
Raleigh, North Carolina 27699-6714. Unless such a demand is made, this permit shall be
final and binding.
Please take notice that this permit is not transferable. The Division may require
modification or revocation and reissuance of the permit. This permit does not affect the legal
requirements to obtain other permits which may be required by the Division of Water Quality
or permits required by the Division of Land Resources, Coastal Area Management Act, or any
other Federal or Local governmental permits may be required.
If you have any questions or need additional information, please contact Ms. Jacquelyn
Nowell at telephone number [phone], extension 512.
Sincerely,
ORIGINAL SIGNED BY
SUSAN A. WIL SORB
Alan W. Klimek, P.E.
cc: Mooresville Regional Office / Surface Water Protection Section
US EPA - Region IV
South Carolina Department of Health and Environmental Control
Jeff Debessonet / 2600 Bull Street Columbia, S.C. 29201
Mecklenburg County WQP
Rusty Rozzelle / 700 N. Tryon St., Suite 205, Charlotte NC 28202
Central Files
Pretreatment Unit / Dana Folley (e-copy)
Aquatic Toxicology Unit
NPDES File

-r
Permit NC0024945
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELI1VIINATI0N SYSTEM
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful standards
and regulations promulgated and adopted by the North Carolina Environmental Management
Commission, and the Federal Water Pollution Control Act, as amended,
Charlotte Mecklenburg Utilities
is hereby authorized to discharge wastewater from a facility located at the
Charlotte Mecklenburg Utilities - Irwin Creek WWTP
`/30f 4000 Westmont Drive
Charlotte
Mecklenburg County
to receiving waters designated as Irwin Creek in the Catawba River Basin in
accordance with effluent limitations, monitoring requirements, and other conditions
set forth in Parts I, II, III and IV hereof.
This permit shall become effective June 1, 2005
This permit and authorization to discharge shall expire at midnight on May 31, 2010.
Signed this day April 29, 2005
ORIGINAL SIGNED BY
SUSAN A. WILSON
Alan W. HIimek, P.E., Director
Division of Water Quality
By Authority of the Environmental Management Commission

Sugar and Irwin NPDES permits review
•
Subject: Sugar and Irwin NPDES permits review
From: "Jarrell, Jackie" <[e-mail]>
Date: Tue, 7 Jun 2005 13:46:56 -0400
To: <[e-mail]>
Hi Jackie, Just to follow up on our phone conversation, in our review we found a
couple of minor items that need to be corrected for consistency purposes. Here they
are:
1. The cover letter also refers to the fecal limit being met by October 1, 2005. In
the permit, Section A.(6) states that the limit "shall become effective no later than
six(6) months from the issuance of the permit (October 1, 2005)". That implies the
date of issuance is April 1, 2005. The cover letter is dated April 29 ( and I guess
date of issuance). The permit effective date is June 1, 2005. We need clarification
as to whether it is six months from April 29 which would be October 29 not October 1
or another date.
. In the Irwin Creek Permit, In the list of plant processes, the dewatering belts and
the UV system are missing. At some point we will need to have that modified. For
the Sugar Creek permit, UV needs to be added. UV for both should probably be
listed as "under construction" since it is not finaled yet.
3. For both Sugar and Irwin, the table of permit limits (Section A.(1)), footnotes 10
and 11 are shown. Footnote 10 does not apply to copper and zinc where it is shown
and there is no footnote 11. It looks like the footnotes as shown below the table are
correct, but are wrong in the table.
4. In Irwin Creek a footnote designation (i.e., number "6") to pH was added where
there should not be a footnote designation. The #6 should be deleted and the
subsequent footnote designations (i.e., 7 through 11) should be renumbered 6
through 10 to correspond to the footnotes following the table.
5. Section A.(9) mentions an attached worksheet for Total Phosphorus Monitoring.
There was no attachment to my copy of the permit.
6. Don't know if this makes a difference or not but in the second paragraph of the
cover, it refers to BOD rather than CBOD. The permit limit in the permit is for CBOD
That is it. Thanks and let me know if you need anything else from us.
Jackie Jarrell
Environmental Management Division Supt.
Charlotte Mecklenburg Utilities
1 of 2 6/16/2005 9:48 AM

Latitude: 35°1 1'44" Sub -Basin:
Longitude: 80°54'27"
Quad #: G15NW Charlotte West NC
Stream Class: C
Receiving Stream: Irwin Creek
Permitted Flow: 15 MGD

• •
Permit NC0024945
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked, and as of this issuance, any previously issued permit bearing this number is no longer
effective. Therefore, the exclusive authority to operate and discharge from this facility arises
under the permit conditions, requirements, terms, and provisions included herein.
Charlotte Mecklenburg Utilities is hereby authorized to:
1. Continue operation of a 15.0 MGD wastewater treatment plant with a discharge through
outfall 001, consisting of the following treatment units :
• Mechanical bar screen
• Influent pump station
• Grit removal
• Flow equalization
• Influent flow measurement
• Three primary clarifiers
• Four trickling filters (Two of the four are standby units, used on an as -needed basis)
• pH adjustment (NaOH)
• Eleven aeration basins (diffused air)
• Three secondary clarifiers
• Chlorine gas disinfection
• Sodium bisulfite dechlorination
• Ten tertiary filters
• Effluent flow measurement
• Cascade aeration
• Four anaerobic digesters
• 300,000 gallon sludge storage
• Two gravity belt thickeners with polymer feed
• 1.8 MG digested sludge storage tank V3 J 1
The facility is located at the CMU Irwin Creek WWTP (4.00CrWestmont Drive, Charlotte] in
Mecklenburg County.
2. Discharge wastewater from said facility at the locations specified on the attached map
through outfall 001 into Irwin Creek, currently classified C waters in the Catawba River
Basin.

r •
Permit NC002494'5
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
During the period beginning on the effective date of the permit and lasting until expiration, the
Permittee is authorized to discharge treated municipal and industrial wastewater from outfall 001.
Such discharges shall be limited and monitored by the Permittee as specified below:
EffluentCliaracterist cs
';Limit's, ' . _
Marutortng �R uiremen�s;
tithly
' Average
'Week[y
.._; •AMA- ge;...'
r 'Daily
?;Average,
'Daily _ ;
010.1. Wit
=;Measuremenni i
r Frequency i
'°Sample:
, Type'
Sample.
. od ti '1;'
Flow
15.0 MGD
Continuous
Recording
I or E
CBOD, 5-day, 20°C (Summer)2.3
5.0 mg/L
7.5 mg/L
Daily
Composite
I, E
CBOD, 5-day, 20°C (Winter)2.3
10.0 mg/L
15.0 mg/L
Daily
Composite
I, E
Total Suspended Residue2
30.0 mg/L
45.0 mg/L
Daily
Composite
I, E
NH3-N (Summer)3
1.2 mg/L
3.6 mg/L
Daily
Composite
E
NH3-N (Winter)3
2.3 mg/L
6.9 mg/L
Daily
Composite
E
Dissolved 0xygen4
Daily
Grab
E
Fecal Coliform
200/ 100mI
400/ 100 ml
1000/100 mi5
Daily
Grab
E
pH6
Daily
Grab
E
Total Residual Chlorine
21 µg/L
28 µg/L
Daily
Grab
E
Temperature
Daily
Grab
E
Conductivity
Daily
Grab
E
Total Nitrogen
(NO2-N + NO3-N + TKN)
Monthly
Composite
E
Total Phosphorus"'
See Special Condition A. (8.) and A. (9.)
Monthly
Composite
E
Cyanide,_Totals' \` _,_.----
... :
`-6:1- µ9ib--..
~....---
\-.22 Pg/L
, ►
-' Gl'ab• -A-
. - t
Mercury,Total
0.015 L°"
µ�
ee
Grab
E
Mickel, Total
106. µg/L--'"-
--26.1-41....,
:_,-Whekly - -\
Composite
' - E '---
Copper, Tota19.1°
21 µg/L
31 µg/L .-i*"1W
ekly
Composite
E
Zinc, Total9.'°
317 pg/L '"Meekly
Composite
E
, Chromium, Total
g
fiI'eialy,--
Composite
E
Chronic Toxicityll
Quarterly
Composite
E
Footnotes:
1. Sample Location: I- Influent, E - Effluent.
2. The monthly average effluent CBOD5 and Total Suspended Residue concentrations shall not exceed 15% of the
respective influent value (85 % removal).
3. Summer is defined as the period from April 1 through October 31, while winter is defined as November 1
through March 31.
4. The daily average dissolved oxygen effluent concentration shall not be less than 6.0 mg/1.
5. See Special Condition A. (6.) for compliance schedule for daily maximum fecal coliform limit.
6. See Special Conditions A. (8.) and A. (9.) for total phosphorus limit and reporting requirements.
7. The Division shall consider all cyanide concentrations reported below the practical quantifiable level (currently
10 µg/L), using the most sensitive method (as stipulated in Part II, Section D, Paragraph 4 of the standard
conditions), to be "zero" for permit -compliance purposes only.
8. If CMUD decides to develop site -specific standards, the proposed course of action should be consistent with
"Interim Guidance on Determination and Use of Water -Effect Ratios for Metals" EPA-823-B-94-001, February
1994. The Division and EPA will review the proposed course of action and may provide comments.
9. The limits stipulated are based on "total recoverable". Alternatively, the permittee may request limits based on
total dissolved as allowed under South Carolina standards.
10. Chronic Toxicity (Ceriodaphnia) at 83%: January, April, July, October (see Special Condition. A. (7.)).
Definitions:
MGD - Million gallons per day
µg/L - Micrograms per liter
mg/L - Milligram per liter ml - Milliliter
CBOD - Carbonaceous Biochemical Oxygen Demand

Permit NC0024945
A. (2.) Irwin Creek Monitoring Requirements
During the period beginning on the effective date of the permit and lasting until expiration, the
Permittee shall monitor Irwin Creek as specified below:
*Orr—
;
oo a ".
i g
,ailit
_1:s�pn Ott 9etremeii--
-
y-ai
nI .
IC1
Irwin Creek - Upstream of Irwin Creek WWTP
Dissolved Oxygen
Variable'
Grab
IC1
Irwin Creek - Upstream of Irwin Creek WWTP
Temperature
Variable'
Grab
IC1
Irwin Creek - Upstream of Irwin Creek WWTP
Conductivity
Variable'
Grab
ICi
Irwin Creek - Upstream of Irwin Creek WWTP
Chromium
Monthly
Grab
IC1
Irwin Creek - Upstream of Irwin Creek WWTP
Copper
Monthly
Grab
IC1
Irwin Creek - Upstream of Irwin Creek WWTP
Zinc
Monthly
Grab
Footnotes:
1. Variable = Weekly (June 1- September 30) and monthly (October 1- May 31)
It is recommended that instream monitoring for stations IC1, SC1, SC2, SC3, SC4, SC5, LSC1, MC1
and MC2 be conducted during the same day or on consecutive days.
Instream monitoring requirements for McAlpine Creek WWTP, Irwin Creek WWTP and Sugar Creek
WWTP are identical. Please submit all instream monitoring results along with the McAlpine Creek
WWTP Discharge Monitoring Reports.
A. (3.) McAlpine Creek Monitoring Requirements
During the period beginning on the effective date of the permit and lasting until expiration, the
Permittee shall monitor McAlpine Creek as specified below:
.
I .
,
... ....... ...- oc`loop... ....r. :.i
-
fi [
f
• .1
C
el rem
ii:
1 c
uue r
�r Ie
Sa
✓r
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Dissolved Oxygen
Variable'
Grab
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Temperature
Variable'
Grab
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Conductivity
Variable'
Grab
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Chromium
Monthly
Grab
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Copper
Monthly
Grab
MC1
McAlpine Creek - Upstream of McAlpine Creek WWTP
Zinc
Monthly
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964 -
Dissolved Oxygen
Variable'
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964
Temperature
Variable'
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964
Conductivity
Variable'
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964
Chromium
Monthly
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964
Copper
Monthly
Grab
MC2
McAlpine Creek downstream of confluence with McMullen Creek at SC 2964
Zinc
Monthly
Grab
Footnotes:
1. Variable = Weekly (June 1 - September 30) and monthly (October 1- May 31)
It is recommended that instream monitoring for stations IC1, SC1, SC2, SC3, SC4, SC5, LSC1, MC1
and MC2 be conducted during the same day or on consecutive days.
Instream monitoring requirements for McAlpine Creek WWTP, Irwin Creek WWTP and Sugar Creek
WWTP are identical. Please submit all instream monitoring results along with the McAlpine Creek
WWTP Discharge Monitoring Reports.

f r
Permit NC00249-45
A. (4.) Sugar Creek Monitoring Requirements
During the period beginning on the effective date of the permit and lasting until expiration, the
Permittee shall monitor Sugar Creek as specified below:
Stat ov
{ID_ `
- k ;Locations '
f
iPara• meter�
{
.IMeasurement�i
;Frequency} i
jjj ' Y i
Sample'
Types
SC1
Sugar Creek downstream of confluence with Irwin Creek at Yorkmont Road
Dissolved Oxygen
Variable'
Grab
SC1
Sugar Creek downstream of confluence with Irwin Creek at Yorkmont Road
Temperature
Variable'
Grab
SC1
Sugar Creek downstream of confluence with Irwin Creek at Yorkmont Road
Conductivity
Variable'
Grab
SC2
Sugar Creek downstream of confluence with Irwin Creek at Arrowhead Road
Dissolved Oxygen
Variable'
Grab
SC2
Sugar Creek downstream of confluence with Irwin Creek at Arrowhead Road
Temperature
Variable'
Grab
SC2
Sugar Creek downstream of confluence with Irwin Creek at Arrowhead Road
Conductivity
Variable'
Grab
SC3
Sugar Creek downstream of confluence with Irwin Creek at Nations Ford Road
Dissolved Oxygen
Variable'
Grab
SC3
Sugar Creek downstream of confluence with Irwin Creek at Nations Ford Road
Temperature
Variable'
Grab
SC3
Sugar Creek downstream of confluence with Irwin Creek at Nations Ford Road
Conductivity
Variable'
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Dissolved Oxygen
Variable'
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Temperature
Variable'
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Conductivity
Variable'
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Chromium
Monthly
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Copper
Monthly
Grab
SC4
Sugar Creek downstream of confluence with Irwin Creek at Route 51
Zinc
Monthly
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Dissolved Oxygen
Variable'
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Temperature
Variable'
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Conductivity
Variable'
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
pH
Variable'
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Ammonia (NH3-N)
Weekly
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Nitrate/Nitrite
(NOX)
Weekly
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Total Kjeldahl
Nitrogen (TKN)
Weekly
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Total Phosphorus
Weekly
Grab
SC5
Sugar Creek downstream of confluence with McAlpine Creek at Route 160
Orthophosphate
Weekly
Grab
Footnotes:
1. Variable = Weekly (June 1— Sept 30) and monthly (Oct 1— May 31)
It is recommended that instream monitoring for stations IC 1, SC1, SC2, SC3, SC4, SC5, LSC 1,
MC 1 and MC2 be conducted during the same day or on consecutive days.
Instream monitoring requirements for McAlpine Creek WWTP, Irwin Creek WWTP and Sugar
Creek WWTP are identical. Please submit all instream monitoring results along with the
McAlpine Creek WWTP Discharge Monitoring Reports.

Permit NC0024945
A. (5.) Little Sugar Creek Monitoring Requirements
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee
shall monitor Little Sugar Creek as specified below:
LSC1
Little Sugar Creek upstream of Sugar Creek WWTP
Dissolved Oxygen
Variable'
Grab
LSC1
Little Sugar Creek upstream of Sugar Creek WWTP
Temperature Variable'
Grab
LSC1
Little Sugar Creek upstream of Sugar Creek WWTP
Conductivity Variable'
Grab
LSC1
LSC1
Little Sugar Creek upstream of Sugar Creek WWTP
Little Sugar Creek upstream of Sugar Creek WWTP
Copper Monthly
Zinc Monthly
Grab
Grab
LSC3
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Dissolved Oxygen Variable'
Grab
LSC3
LSC3
LSC3
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Temperature Variable'
Conductivity Variable'
Chromium Monthly
Grab
Grab
Grab
LSC3
LSC3
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Little Sugar Creek downstream of Sugar Creek WWTP at Highway 51
Copper Monthly
Zinc Monthly
Grab
Grab
Footnotes:
1. Variable = Weekly (June 1— Sept 30) and monthly (Oct 1— May 31)
It is recommended that instream monitoring for stations IC1, SC1, SC2, SC3, SC4, SC5, LSC1,
MC 1 and MC2 be conducted during the same day or on consecutive days.
Instream monitoring requirements for McAlpine Creek WWTP, Irwin Creek WWTP and Sugar
Creek WWTP are identical. Please submit all instream monitoring results along with the
McAlpine Creek WWTP Discharge Monitoring Reports.
The revised instream monitoring program, no longer requires monitoring of station LSC2. The
LSC2 designation continues to refer to the sampling station on Little Sugar Creek downstream of
the Sugar Creek WWTP at Archdale Road; however, this station is inactive.
A. (6 DAILY
Tl} - d . . • um limi
ftom the ' uance of the 1 _ ( )
FECAL OLIFORM :LIIVIIT i
e6a1 coliforn shall become effective "no later than.six(6) m nths
rmit October 1�2OO5 .

Permit NC0024945
A. (7.) CHRONIC TOXICITY PERMIT LIMIT (Quarterly)
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant
mortality to Ceriodaphnia dubia at an effluent concentration of 83.0%.
The permit holder shall perform at a minimum, quarterly monitoring using test procedures outlined in
the "North Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised February 1998, or
subsequent versions or "North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure"
(Revised -February 1998) or subsequent versions. The tests will be performed during the months of
January, April, August, and October. Effluent sampling for this testing shall be performed at the NPDES
permitted final effluent discharge below all treatment processes.
If the test procedure performed as the first test of any single quarter results in a failure or ChV below
the permit limit, then multiple -concentration testing shall be performed at a minimum, in each of the
two following months as described in "North Carolina Phase II Chronic Whole Effluent Toxicity Test
Procedure" (Revised -February 1998) or subsequent versions.
The chronic value for multiple concentration tests will be determined using the geometric mean of the
highest concentration having no detectable impairment of reproduction or survival and the lowest
concentration that does have a detectable impairment of reproduction or survival. The definition of
"detectable impairment," collection methods, exposure regimes, and further statistical methods are
specified in the "North Carolina Phase II Chronic Whole Effluent Toxicity Test Procedure" (Revised -
February 1998) or subsequent versions.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the months in which tests were performed, using the parameter
code TGP3B for the pass/fail results and THP3B for the Chronic Value. Additionally, DWQ Form AT-3
(original) is to be sent to the following address:
Attention: NC DENR / DWQ / Environmental Sciences Branch
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
Completed Aquatic Toxicity Test Forms shall be filed with the Environmental Sciences Branch no later
than 30 days after the end of the reporting period for which the report is made.
Test data shall be complete, accurate, include all supporting chemical/physical measurements and all
concentration/response data, and be certified by laboratory supervisor and ORC or approved designate
signature. Total residual chlorine of the effluent toxicity sample must be measured and reported if
chlorine is employed for disinfection of the waste stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required, the
permittee will complete the information located at the top of the aquatic toxicity (AT) test form indicating the facility
name, permit number, pipe number, county, and the month/year of the report with the notation of "No Flow" in the
comment area of the form. The report shall be submitted to the Environmental Sciences Branch at the address
cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, monitoring will be
required during the following month.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of Water
Quality indicate potential impacts to the receiving stream, this permit may be re -opened and modified to include
alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control organism
survival, minimum control organism reproduction, and appropriate environmental controls, shall constitute an
invalid test and will require immediate follow-up testing to be completed no later than the last day of the month
following the month of the initial monitoring.

Permit NC0024945
A. (8.) Total Phosphorus Limit
As stipulated by the 2002 Settlement Agreement between Charlotte -Mecklenburg Utilities
(CMU), the South Carolina Department of Health and Environmental Control (SC DHEC) and the North
Carolina Division of Water Quality (NC-DWQ), CMU's McAlpine Creek WWTP, Sugar Creek WWTP and
Irwin Creek WWTP must comply with a limit of 826.0 lbs/day. This limit is defined as an effluent limit
for total phosphorus from the total combined discharge from the three referenced CMU wastewater
treatment plants (based on a 12-month rolling average). The methodology for calculating the annual
average is described in Part A. (9.).
If CMU conducts construction activities associated with phosphorus removal at either the
Sugar Creek WWTP or the Irwin Creek WWTP, the annual average limit of 826.0 lbs/day (based on the
collective discharge from all three plants) shall become effective February 28, 2007. Said construction
activities will also trigger an effluent limit for total phosphorus for the Irwin Creek WWTP of 250.0
lbs/day (based on a monthly average) as of February 28, 2007 (as stipulated in Part. A. (1.) of NPDES
Permit NC0024945). If however, CMU decides not to pursue construction activities, associated with
phosphorus removal, at either the Sugar Creek WWTP or the Irwin Creek WWTP, the total phosphorus
annual average limit applicable to the loading from all three WWTPs, shall become effective on February
28, 2006.
A. (9.) Total Phosphorus Monitoring
The Permittee shall calculate a 12-month rolling average mass loading as the sum of monthly
loadings, according to the following equations:
(1) Monthly Average (lbs./day) = TP x Qw x 8.34
where:
TP = the arithmetic average of total phosphorus concentrations (mg/L) obtained via composite
samples (either daily, weekly, or monthly average values) collected during the month
Qw = the average daily waste flow (MGD) for the month
8.34= conversion factor, from (mg/L x MGD) to pounds
The 12-month rolling average mass loading is defined as the sum of the monthly average loadings for
the previous 12 months inclusive of the reporting month:
12
(2) 12-Month Mass Loading (lbs./day)= E TPma =12 (inclusive of reporting month)
1
Where:
TPma is defined as the total phosphorus monthly average mass loading (calculated above).
The monthly average and 12-month average mass loadings shall be reported on the attached worksheet
and submitted with the discharge monitoring report for McAlpine Creek WWTP. The first worksheet is
due with the discharge monitoring report, 12 months from the effective date of the total phosphorus
limit (referenced in Special Condition A. (8)). In the interim period between the effective date and the
requirement to submit the attached worksheet, the total phosphorus monthly average mass loadings
should be reported on the discharge monitoring report for the respective facility.
The Permittee shall report the total phosphorus concentration for each sample on the appropriate
discharge monitoring report for each facility. Reporting of and compliance with the phosphorus limit
shall be done on a monthly basis.

Permit NC0024945
A. (10.) Effluent Pollutant Scan
The permittee shall perform an
Ammonia (as N)
Chlorine (total residual, TRC)
Dissolved oxygen
Nitrate/Nitrite
Kjeldahl nitrogen
Oil and grease
Phosphorus
Total dissolved solids
Hardness
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thallium
Zinc
Cyanide
Total phenolic compounds
Volatile omanic compounds:
Acrolein
Acrylonitrile
Benzene
Bromoform
Carbon tetrachloride
Chtorobenzene
Chlorodibromomethane
Chloroethane
2-chloroethylvinyl ether
Chloroform
Dichlorobromomethane
1,1-dich!oroethane
1,2-dichloroethane
annual pollutant scan of its treated effluent for the following parameters:
Trans-1,2-dichloroethylene Bis (2-chloroethyi) ether
1,1-dichbroethylene Bis (2-chloroisopropyl) ether
1,2-dichloropropane Bis (2-ethylhexyl) phthalate
1,3-dichbropropylene 4-bromophenyl phenyl ether
Ethylbenzene
Methyl bromide
Methyl chloride
Methylene chloride
Butyl benzyl phthalate
2-chloronaphthalene
4-chlorophenyl phenyl ether
Chrysene
1,1,2,2-tetrachloroethane Di-n-butyl phthalate
Tetrachloroethylene Di-n-octyl phthalate
Toluene Dbenzo(a,h)anthracene
1,1,1-trichloroethane 1,2-dichlorobenzene
1,1,2-trichbroethane
Trichloroethylene
Vinyl chloride
Acid -extractable compounds:
P-chloro-m-creso
2-chlorophenol
2,4-dichlorophenol
2,4-dimethylphenol
4,6-dinitro-o-cresol
2,4-dinitrophenol
2-nitrophenol
4-nitrophenol
Pentachlorophenol
Phenol
2,4,6-trichbrophenol
Base -neutral compounds:
Acenaphthene
Acenaphthytene
Anthracene
Benzidine
Benzo(a)anthracene
Benzo(a)pyrene
3,4 benzofluoranthene
Benzo(ghi)perylene
Benzo(k)fluoranthene
Bis (2-chtoroethoxy) methane
1,3-dichlorobenzene
1,4-dichbrobenzene
3,3-dichbrobenzidine
Diethyl phthalate
Dimethyl phthalate
2,4-dinitrotoluene
2,6-dinitrotoluene
1,2-diphenyihydrazine
Fluoranthene
Fluorene
Hexachlorobenzene
Hexachlorobutadiene
Hexachbrocydo-pentadiene
Hexachloroethane
lndeno(1,2,3-cd)pyrene
Isophorone
Naphthalene
Nitrobenzene
N-nitrosodi-n-propylamine
N-nitrosodimethylamine
N-nitrosodiphenylamine
Phenanthrene
Pyrene
1,2,4-trichlorobenzene
➢ The total set of samples analyzed during the current term of the permit must be representative of
seasonal variations.
➢ Samples shall be collected and analyzed in accordance with analytical methods approved under
40 CFR Part 136.
➢ Unless indicated otherwise, metals must be analyzed and reported as total recoverable.
➢ Test results shall be reported to the Division in DWQ Form- DMR-PPA1 or in a form approved by
the Director, within 90 days of sampling. A copy of the report shall be submitted to each the
NPDES Unit and the Compliance and Enforcement Unit to the following address: Division of
Water Quality, Water Quality Section, 1617 Mail Service Center, Raleigh, North Carolina 27699-
1617.

Department of Environment and Natural Resources
Division of Water Quality
Amendment to Fact Sheet For NPDES Permit NC0024945
Facility Information
Applicant/Facility Name':
Applicant Address4:
Facility Address4:
Permitted Flow2.4,7:
Type of Waste2,47:
Facility/Permit Status4:
County2,4'7:
Miscellaneous
Receiving Stream2,4:
Stream Classification1'2:
303(d) Listed?5:
Subbasin2:
Drainage Area (mi2): [calculated]
Summer 7Q10 (cfs)6:
Winter 7Q10 (cfs)6:
Average Flow (cfs)6:
IWC (%):
Primary SIC Code:
Regional Office:
USGS Topo Quad:
Permit Writer:
Date:
Factsheet Amendments
Charlotte Mecklenburg Utilities — Irwin Creek
5100 Brookshire Blvd.
4000 Westmont Drive
15.0 MGD (Grade IV — Biological)
Municipal (Domestic and Industrial)
Renewal
Mecklenburg
Irwin Creek
C
Yes — Fecal Coliform, Turbidity
03-08-34
31.0 mi2
4.9 cfs
7.7 cfs
43.0 cfs
83%
4952
Mooresville
Charlotte West (G 15 NW)
Jacquelyn M. Nowell
April 1, 2005
The following amendments have been made to the factsheet dated July 11, 2003 and have been
incorporated into the final permit dated April 22, 2005 for the CMU-Irwin Creek WWTP.
• Based on additional review of the reasonable potential analysis, the effluent limit
and monitoring requirement for silver has been removed from the NPDES
permit. All the reported effluent values are below detection, therefore no
potential for exceeding the State action level exists. Silver will continue to be
monitored during the long term monitoring plan of the pretreatment program
for the Irwin Creek treatment facility.

• There have been revisions to the total copper and total zinc limits that are
included in this permit for the protection of South Carolina waters. Upon receipt
of additional information from CMU and South Carolina Department of Health
and Environmental Control (SCDHEC), DWQ is including the permit limits that
have been mutually agreed upon. Attached is a summary document that
illustrates how the limits were derived. The weekly average and daily
maximum limitations for copper are 21 ug/1 and 31 ug/1, respectively. The daily
maximum limit for zinc is 317 ug/l.
If CMU decides to develop site -specific standards, the proposed course of action
should be consistent with "Interim Guidance on Determination and Use of
Water -Effect Ratios for Metals" EPA-823-B-94-001, February, 1994. As
previously mentioned, these limitations have been implemented based on
protection of South Carolina waters and standards. South Carolina standards
allow for NPDES limit development based on the dissolved fractions for copper
and zinc. Since the limits specified in this permit are based on "total
recoverable", CMU may request limits for copper and zinc based on the total
dissolved fraction.
• A schedule for compliance for the daily maximum fecal coliform limit has
been granted and must be met by October 1, 2005.
• The site for downstream monitoring station LSC3 has been changed from
Route 521 to Highway 51 to allow safe access for CMU monitoring
personnel per the October 18, 2004 permit minor modification.
• The draft permit contained monthly average limits for ammonia. In
order to protect North Carolina's ammonia standards, the limitations for
ammonia have been revised. In addition to the monthly average limit
proposed in the draft permit, the final permit contains a summer 3.6
mg/L weekly average ammonia limit and a winter 6.9 mg/L weekly
average ammonia limit.
• This permit will expire on May 31, 2010 and will place the CMU permit
back on schedule in the Catawba River Basin. The expiration date will
allow the milestone date stipulated in the 2002 Settlement Agreement to
occur within the term of this permit.
•
The following changes were previously noted in the July 11, 2003 factsheet:
• Sampling type for mercury has been changed from composite to grab.
• Based on comments received during the public comment period, the total
phosphorus condition has been modified to reflect the requirements of the 2002
Settlement Agreement.

• Since outfall 002 no longer exists, it has been removed from the permit.
• Based on comments received during the public comment period, a fecal coliform
daily maximum limit of 1000/100 ml has been added to the permit. The new
limit is consistent with the EPA approved Fecal Coliform Total Maximum Daily
Load (TMDL) for Irwin, McAlpine, Little Sugar, and Sugar Creek Watersheds.
This TMDL was developed by the Mecklenburg County Department of
Environmental Protection with active participation by the South Carolina
Department of Health and Environmental Control (SC DHEC), North Carolina
Division of Water Quality (NC DWQ), Charlotte Mecklenburg Utilities (CMU)
and United States Geological Survey (USGS). As previously noted, this limit
will become effective on October 1, 2005.
• Based on comments received during the public comment period, the
summertime instream monitoring frequency has been modified to weekly. The
draft permit did not reflect the modifications to the monitoring frequency
implemented in 2001. Therefore, the summertime instream monitoring
frequencies were modified to be consistent with this modification.
• Based on comments received during the public comment period, the footnotes
have been corrected establishing the practical quantitation limits and reporting
requirements for cyanide. The permit requires that the permittee use analytical
methods capable of quantifying the pollutants below the permit discharge
requirements and all data generated must be reported down to the
minimum detection or lower reporting level of the procedure. If no
approved methods are determined capable of achieving minimum
detection and reporting levels below permit discharge requirements, then
the most sensitive (method with the lowest possible detection and
reporting level) approved method must be used.
• Based on comments received during the public comment period, compliance
with the total residual chlorine limit will be based on a daily average.
• In response to the new NPDES municipal application data requirements, DWQ
is reinstating annual effluent pollutant scans into municipal permits. Special
Condition A.(9.) of this permit details this requirement. Be advised that
pollutant scan data are required to be submitted on the Discharge Monitoring
Report Form for the appropriate month. Upon renewal of this permit, CMU
should use this data in completing the application.
In addition to the effluent pollutant scan monitoring requirements stipulated in
the new NPDES municipal applications, facilities discharging greater than 1 MGD or
having a pretreatment program are required to conduct additional whole effluent
toxicity monitoring prior to submittal of the permit renewal application. This additional
toxicity monitoring must be completed on a second species (one other than the species

specified in the permit) and include four test either quarterly within one year of
application submittal or annually within four and one-half years of application
submittal. Though this monitoring is not a condition for this permit, the facility should
make plans to conduct this additional monitoring .
The above statements include all the changes made to the CMU- IrwinCreek WWTP
permit
Issuance Date: April 22, 2005
Effective Date: June 1, 2005
Expiration Date: May 31, 2010
STATE CONTACT:
If you have any questions on any of the above information, please contact Jackie Nowell
at 919-733-5083 ext. 512
OGie
A .
DATE:

Marshall's comments on CMUs and Albemarle
•
Subject: Marshall's comments on CMUs and Albemarle
From: Jackie Nowell <jackie.nowell@ncmail net>
Date: Thu, 14 Apr 2005 14:43:44 -0400
To: Susan A Wilson <Susan.A.Wilson®ncmail.net>
(Since you don't like walk-ins, you get to read a long email)
Talked with Marshall, regarding CMU plants: 1) he's okay with the 6 month compliance
schedule for fecal, considering that originally they had asked for 12 months. 2) he's also okay
with allowing CMU the option of doing a WER. EPA would like to review their plan of study
and implementation plan. He also said to let CMU know that if the WER indicates that more
stringent limits should be applied, then CMU would be bound by the results. They cannot
decide not to accept the results. 3) Also ok with more stringent NH3 limits.
So, I can proceed to finalize the CMU permits , ' frp�r Ac su�� �Not42' -Plat wbuL i
N $ +DRIB Wet_ Nu.µ -2--
Albemarle --- He recognizes that Albemarle has a problem, influent TSS values are as low as
he's ever seen. But he thinks there is a seasonal component to their problem, the winter
months,esp. Feb. and March are when they have the problem. He has a two fold
recommendation for us to ponder -- 1) Continue with a % removal less that 85% but not as
low as 62% because he doesn't think that 62% is warranted.. He looked at the average
removal from 2001 -2004 and by his calculations it was 80%, 75%, 63%, 81%, respectively.
the average of the 4 years was 75%. We could think about what we would recommend.
2) make the variation of the % removal for basically the winter months only since those
appear to be the problem times. We could designate what the winter months would be. Then
come up with what percent removal we would allow for those months.
I told him that I don't think that last option had ever been done, but that I would consult
with staff and get back with him. the first option to increase % removal from 62% up to some
number is the easiest thing to do. The winter only option will take some more work. Do you
have a sagely recommendation?
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The calculations used to convert the dissolved metal criterion for copper or zinc to
the total recoverable form in the permit, based on the partitioning of the. metal with
suspended solids, are described in EPA's "The Metals Translator: Guidance for
Calculating a Total Recoverable Permit Limit from a Dissolved Criterion" (EPA 823-B-
96-007, June 1996). The Guidance provides the following equation (Equation 2.7,
Guidance C 10) to determine the dissolved fraction of the metal based on ambient total
suspended solids (TSS).
where:
fD (1+Kpxm)
1
fo = dissolved fraction of the metal, decimal
Kp = partition coefficient, LJmg
m = TSS, mg/L
[Eqn. 2.7]
The Guidance also provides an equation to determine the partition coefficient (Kp) for
various metals, including copper and zinc. This equation is provided in Table 3
(Guidance @ 6) as:
where:
Kp = KPo XTSSa [1]
Kp = partition coefficient, L/kg
KPo = metal -specific partition coefficient at 0 mg/1 TSS, L/kg
for copper, Kpo =1.04E+6
for zinc, KPo =1.25E+6
TSS = ambient total suspended solids, mg/1
a = metal -specific coefficient
for copper, a =-0.7436
for zinc, a =-0.7038

t
Note that equation [1] defines the partition coefficient with the units L/kg while equation
2.7 defines the partition coefficient with the units L/mg. To make these two forms
compatible, divide the results from equation [1] (i.e., L/kg) by 1,000,000 mg/kg to
convert them to the proper units (i.e., Llmg) for equation 2.7.
Then, for the ambient TSS of 2.15 mg/1 for Irwin Creek and the ambient TSS of
2.30 mg/1 for Sugar Creek, we calculate the following dissolved fractions for copper and
zinc.
Table 1
TSS-Dependent Dissolved Fraction
Irwin Creek
Sugar Creek
Parameter
Copper
Zinc
Copper
Zinc
TSS
2.15
2.15
2.30
2.30
TSSa
=
2.15-0.7436
0.566
2.15-0.7038
0.583
2.30-0.7436
0.538
2.30-0.7038
0.556
Kp (Equ. 1)
0.589
0.729
0.560
0.696
(1+Kp x m)
2.266
2.568
2.288
2.600
fD (Equ. 2.7)
0.441
0.389
0.437
0.385
The final limits for each metal are determined by dividing the waste load
allocation, expressed as the dissolved form of the metal, by the dissolved fraction given in
Table 1. The dissolved water quality standard, used to establish the waste load allocation,
is determined as the product of the hardness -based water quality standard and the
dissolved fraction associated with the hardness -dependent standard.
Page 2

Irwin Creek - Copper Calculations
Knowns - from the SC DEHEC Bureau Water Classifications and Standards Attachment II
For Copper
mA
bA
mC
bC
dissolved fractions
acute
chronic
0.9422
-1.700
0.8545
-1.702
96%
96%
Hardness
85
In(85)
4.442651
In(85)
4.442651
{
{0.9422(4.442651)+(-1.700)}
=
2.485866
{08545(4.442651)+(-1 702)}
=
2.094245
exp
2.485866
=
12.01152
exp
2.094245
=
8.119313
copper dissolved fraction
96%
=
11.53106
WQS dissolved
copper dissolved fraction
96%
=
7.79454
WQS dissolved
Plant permitted flow
15
MGD
Plant permitted flow
15
MGD
Steam flow
4.9
CFS
Steam flow
4.9
CFS
Stream flow in MGD
3.1667328
Stream flowin MGD
3.166733
_
Combined Flow
18.1667328
Combined Flow
18.16673
WLA dissolved! ound;
p
1.747076833
WLA dissolved/pound;
1.180955
WLA ug/I
13.96544231
WLA ug/I
9.440089
Calculated Dissolved d
0.441
WQBEL - total recove
31.66766964
WQBEL - total recover
21.4061

I I I I I Irwin Creek - Zinc Calculations
"
Knowns - from the SC DEHEC Bureau Water Classifications and Standards Attachment I1
For Zinc
mA
bA
mC
bC
dissolved fractions
acute
chronic
0.8473
0.884
0.8473
0.884
97.8%
98.6%
Hardness
85
In(85)
4.442651
In(85)
4.442651
{
{0.8473(4.442651)+(-0.884))
=
4.648258
{0.8473(4.442651)+(-0.884))
=
4.648258
exp
4.648258
=
104.403
exp
4.648258
=
104.403
copper dissolved fraction
97.8%
=
102.1061
WQS dissolved
copper dissolved fraction
98.6%
=
102.9414
WQS dissolved
Plant permitted flow
15
MGD
Plant permitted flow
15
MGD
Steam flow
4.9
CFS
Steam flow
4.9
CFS
I
Stream flow in MGD
3.1667328
Stream flow in MGD
3.166733
1
I
Combined Flow
18.1667328
Combined Flow
18.16673
I
WLA dissolved/pound:
15.47015666
WLA dissolved/pound:
15.5967
WLA ug/I
123.6623234
WLA ug/i
124.6739
Calculated Dissolved F
0.389
I
WQBEL - total recover 317.8980037
WQBEL - total recover
320.4984

REASONABLE POTENTIAL ANALYSIS
CMU- Irwin Creek WWTP
NC0024945
Time Period 07 2001-07 2003
Ow (MGD) 15
7010S (cfs) 4.9
7010W (cfs) 7.7
30Q2 (cfs) 9.9
Avg. Stream Flow, QA (cfs) 43
Reeving Stream Irwin Creek
WWTP Class IV
IWC (%) 0 7010S 82.593
41, 7Q10W 75.121
30Q2 70.136
® QA 35.094
Stream Class C
Outfall 001
Qw=15MGD
PARAMETER
TYPE
(1)
STANDARDS &
CRITERIA (2)
POL
Units
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
NC WQS/
Monk
fi FAV/
Aeub
n
I Drt Ma And Cw Mond* Or
Arsenic
NC
50
ug/L
0
0
N/A
Acute: WA
_
Chronic: ---61-----
---------------•-------•—•---
Beryllium
C
6.5
ug/L
0
0
N/A
Acute: WA
Chronic: —5"--------
Cadmium
NC
2
15
ug/L
0
0
WA
Acute: 15
_ _ --___—------------------_-------_-----
Chronic: 2
Chromium
NC
50
1,022
ug/L
0
0
N/A
Acute: 1,022
_ _"61 _—_--_—_—•—_—•—•_
Chronic:
—•—
Copper
NC
7
AL
7.3
ug/L
131
131
39.1
Acute: 7
-- —_—_—•—.—•-----_—_—_---_—_—_---_—
Chronic: 8
Cyanide
NC
5
N
22
10
ug/L
0
0
WA
Acute: 22
_ --__—�--
• Chronic: 6
_.—.—.—•-----_---------_—_--—
Fluoride
NC
1,800
ug/L
0
0
WA
Acute: WA
_nic: 2,17_ _ 9_
Chro
— - - —•---------------•-----•---
Lead
NC
25
N
33.8
ug/L
0
0
WA
Acute: 34
__ _ ____—r----.—.—.—.---------------_—_---
Chronic: -30
Mercury
NC
0.012
0.0002
ug/L
0
0
WA
Acute: N/A
_ -- _—+--•—•--------___--_---•--_
Chronic: - 0
---•—
Molybdenum
A
3,500
ug/L
0
0
N/A
Acute: WA
_ __----_—_—•—_—._
• Chronic: 4,990
—_—•—_—.—_—_—_—•—
Nickel
NC
88
261
ug/L
0
0
WA
Acute: 261
_ _ -_ _
Chronic: 107
------------------.—.—.—_—_—_---
Phenols
A
1
N
ug/L
0
0
N/A
Acute: N/A
Ch_r_onic: --- T -----
—•—•-------------------•—•—•—
Selenium
NC
5.0
56
ug/L
0
0
WA
Acute: 56
_ _ --__—__-----.—_—.—_—_—.—•—.—_---_—_—__
• Chronic: 6
Sliver
NC
0.06
AL
1.23
ug/L
115
0
WA
Acute: 1
_ _ -- - __—_----_—.—_—_—_—_—_—_—_—_—_—_—_—_—
• Chronic: 0
Zinc
NC
50
AL
67
ug/L
132
132
154.7
Acute: 67
_ _ —�.
. Chronic: --61-
_—_—.—_—_—___—•—•— •—
— — - — — —
'Legend:
C = Carcinogenic
NC = Non -carcinogenic
A = Aesthetic
— Freshwater Discharge
IrwtnCr04run, rpa
2/10/2005

Irwin Creek WWTP Recalculated Cu and Zinc Limits (ug/I)
DWQ- AL Recalc
19.4
163.4
CMU - 8/19/04
31.6
317.5
the above limits factor
in TSS data and partitioning
coefficients
85 mg/I
Running average/median
1995-2000,2002-2004
DWQ- Proposed
DWQ - Revised
CMU - 7/1/04
SCDHEC Recomm. 2/7/05
Final Limits Sep 03
as of Ma v 04
Copper (acute)
5.3
8.4
14.6
31.6
Copper (chronic)
4.7
7.0
9.8
21.6
Zinc
50.4
75.5
126.4
317.6
Hardness value used
36 mg/I
58 mg/I
85 mg/I
Statistical value of H
min./ 1st percentile
10th percentile
Running average/median
Period of record
1983-2000
1983-2000
1995-2000,2002-2004
DWQ median hardness
76 mg/I
DWQ mean hardness
79.8 mg/I
Sugar Creek WWTP Recalculated Cu and Zinc Limits (ug/I)
DWQ- AL Recalc
CMU - 8/19/04
DWQ- Pro • osed
DWQ - Revised
Final Limits Sep 03
as of Ma 04
CMU - 7/1/04
SCDHEC Recomm. 2/7/05
Copper (acute)
3.9
7.5
17.8
149.8
10.1
22.1
228.4
the above limits factor
in TSS data and partitioning
coefficients
63 mg/I
Running average/median
1997-2000.2002-2004
22
Copper (chronic)
3.2
5.8
7
15.3
Zinc
38.3
68.4
89.9
228.4
Hardness value used
26 mgA
51.6 mg/I
63 mg/I
Statistical value of H
min./1st percentile
10th percentile
Running average/median
Period of record
1989-2000
1989-2000
1997-2000.2002-2004
DWQ median hardness
65.2 mg/l
DWQ mean hardness
66.1 mg/I

CHARLOTTE,., •
March 11, 2005
Ms. Jackie Nowell
NC-DENR, DWQ
Point Source Branch
1617 Mail Service Center
Raleigh, NC 27699-1617
Re: Irwin Creek WWTP — NPDES #NC0024945
Sugar Creek WWTP — NPDES #NC0024937
Dear Ms. Nowell,
APR 1 2005 1j1J
DErdR - WATEti UAUn
POINT SOURCE BRANCH
Thank you for allowing us to submit information about the status of our new disinfection
systems that are presently being completed at Sugar Creek and Irwin Creek Treatment
Facilities. As you are aware, these facilities were designed to meet the new fecal
coliform daily maximum limit of 1000/100 ml as required in the implementation plan for
the fecal coliform TMDL in the greater Sugar Creek Watershed. During the time that
the permits for these two facilities have been expired we have gone ahead and designed
and constructed these facilities to meet the new limits. The previous disinfection systems
at these plants used chlorine gas to disinfect but were not able to meet this daily
maximum limit.
The construction at both facilities is almost complete but we are encountering some
problems and the Design Engineer, Camp, Dresser and McKee (CDM), is not ready to
sign that the project is complete. Though the UV system appears to be functioning well
at this time, we have experienced problems with the HVAC for the UV powerhouse. We
have had fuses blow in the HVAC system that has caused overheating in the powerhouse
and we want to make sure these issues are resolved before disassembling the existing
chlorine disinfection system. The HVAC system for the powerhouse will encounter the
largest strain during the hot summer months, and we need to make sure the system will
work during this time period before we can state we can meet the new daily maximum
fecal coliform limits.
We would like to request a 6-month Schedule of Compliance for completing any
upgrades we may need to the HVAC system on the UV powerhouse to make sure we can
meet the new limit. We feel that by the end of the hot summer months we should
encounter and resolve any issues we may have. In the interim, we will do everything
possible at our facilities to meet and exceed the new limit.
CHARLOTTE-MECKLENBURG UTILITIES
Environmental Management Division
4000 Westmont Drive
Charlotte, NC 28217
PI-1: 704/357-1344

The second comment we would like to submit is about completing a Water Effects Ratio
(WER) to determine site -specific limits for copper and zinc for the Sugar and Irwin Creek
facilities. We would like a clause added to the Permits for these facilities stating that we
may conduct the WER's to determine site -specific limits and that the State would take the
WER results into consideration to adjust the permitted limits for these parameters to
reflect the site -specific limits determined in the study.
Thanks again for your consideration on these issues and for all the work you've been
doing to help us resolve the issues in this permitting process. If you have any questions
about these requests, or if you need further information, please feel free to call me at
704/357-1344, ext. 238 or Dawn Padgett at 704/357-1344, ext.235.
Sincerely,
•
acqueline A. Jarrell, P.E.
Superintendent
Environmental Management Division
Charlotte Mecklenburg Utilties

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UV Systems at Irwin and Sugar Creek WWTP's
t
t
Y
Subject: UV Systems at Irwin and Sugar Creek WWTP's
From: "Padgett, Dawn" <[e-mail]>
Date: Fri, 18 Feb 2005 15:20:26 -0500
To: <[e-mail]>
CC: "Jarrell, Jackie" <[e-mail]>, "Gullet, Barry"
<[e-mail]>, "McLelland, Julie"
<JMcLelland @ ci.charlotte.nc.us>
Hi Jackie, You wanted us to send you some information about where we are at the
plants in the process to meet the proposed 1,000/100 ml daily maximum fecal
coliform limit. At this time the new UV disinfection systems are in place. These
systems have been designed to meet the 1,000/100 ml daily maximum limit.
However, they have only been completed recently and the chlorine disinfection
systems, which are not designed to meet this limit, are still in place. The chlorine
system's will remain in place until all of the specifications for the system have been
met. During this interim period, we would like an extension for at least a year before
the new limit comes into effect. This will allow us to time for the new systems to
meet the specification's and for our staff to learn how to optimize the operation's of
these systems.
Attached is a note from the Capital Improvement Program staff about the current
status of the UV upgrades. Please let me know if you have any questions, or if you
need any further information.
Thanks,
Dawn Padgett
Environmental Management Division
Charlotte Mecklenburg Utilities
704/357-1344, ext.235 «UV Update for DENR 2 05.doc»
1 of 1 2/18/2005 5:35 PM

Y
UV Update — February 2005 (Sugar and Irwin)
UV facilities have been installed and are being tested. The chlorine facilities remain
at this time as a backup when the UV system needs to be shut down to perform
adjustments based on test results. When the City is certain that the UV system meets all
specifications, the chlorine systems will be decommissioned. Initial testing indicates that
the system will meet all current permit requirements as designed.
The UV system is provided by Wedeco. United States headquarters have recently been
relocated to Charlotte. The company is based in Germany and has installations
worldwide, including a significant number in the United States.

Re: CMU explanation
Subject: Re: CMU explanation
From: Matt Matthews <[e-mail]>
Date: Fri, 11 Feb 2005 08:40:32 -0500
To: Jackie Nowell <[e-mail]>
CC: Susan A Wilson <[e-mail]>
I was able to reproduce their calculations independently (see attached spreadsheet). So,
assuming that the hardness and TSS values provided are accurate and appropriate, I'm
OK with the numbers. You'll note that my final values are slightly off from their's,
most likely due to rounding errors. I followed strict significant figure rules for
intermediate calculations.
I also looked at the last couple of years worth of data; they had three values in excess
of the proposed chronic limit and also appear to have RP (for copper).
Matt
Jackie Nowell wrote:
Matt Matthews
NC DENR/Division of Water Quality
Aquatic Toxicology Unit
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
v-[phone]
f-[phone]
MailTo:[e-mail]
http://www.esb.enr.state.nc.us
1 of 1 2/15/2005 12:12 PM

CMUD Irwin Creek Copper Site -Specific Criterion and Limit Derivation
Acute Chronic
Hardness Conversion
TSS Conversion
Permit Limit
CMC=exp{ma[In(hardness)]+ba}(CF) CCC=exp{mc[In(hardness)]+bc}(CF)
ma 0.9422 me 0.8545
ba -1.7 be -1.702
CF 0.96 CF 0.96
Hardness 85 Hardness 85
CMC (ug/L) 11.5 CCC (ug/L) 7.8
Kp=Kpo x TSSa
TSS 2.15
a -0.7436
TSS-a 0.566
Kpo 1.04E+06
Kp 0.589
fd=1 /(1 +Kp x TSS)
fd 0.441
CMC=CMC/fd CCC=CCC/fd
CMC (ug/L) 26.1 CCC (ug/L) 18
PF(MGD) 15
7Q10 (cfs) 4.9
IWC (%) 83
Acute Limit (ug/L) 31 Chronic Limit (ug/L) 22

Re: NC Facilities Sugar Creek & Irwin Creek NPDES Li...
t_
•
Subject: Re: NC Facilities Sugar Creek & Irwin Creek NPDES Limits (Copper &
Zinc) Revised
From: "Michael Montebello" <[e-mail]>
Date: Mon, 07 Feb 2005 11:35:10 -0500
To: <j ackie.nowell @ ncmail.net>
CC: "Jeff DeBessonet" <[e-mail]>, <[e-mail]>
Ms. Nowell,
Based on your additional information provided today, I have revised
the
limited noted below.
As noted earlier,we also specify that a CCC be used as a chronic
value
and a CMC be used as an acute value. In the case of Zinc the CMC is
lower than the CCC (due to the development of the standard) so only
a
daily maximum is necessary.
This results in the followin9)limits (that would be protective of SC
Water Quality Standards) for the noted facilities (based on the
assumptions above).
Irwin Creek (15 MGD)
Copper
Monthly Average (ug/1) 21.6
Daily Maximum (ug/1) 31.6
Zinc
Daily Maximum (ug/1) 317.6
Sugar Creek (20 MGD)
Copper
Monthly Average (ug/1) 15.3
Daily Maximum (ug/l) 22
Zinc
Daily Maximum (ug/1) 228.4
These values are similar to the proposed WQBEL noted (except for the
additional use of a monthly copper limit (or a weekly limit if that
is
your preference). We would like to see any revised draft permit
limits
for these permits if you make changes to the permits.
Thank You,
Mike Montebello
Michael Montebello, Manager
1 of 2 2/7/2005 11:47 AM

Re: NC Facilities Sugar Creek & Irwin Creek NPDES Li...
Domestic Wastewater Permitting Section
Phone [phone]
Fax [phone]
[e-mail]
Jackie Nowell <[e-mail]> 11/2/2004 2:51:59 PM
»>
Mike,
Attached is the information you requested. Permits highlighted in
Carolina Blue will have maps faxed to you.
Jackie Nowell
2 of 2 2/7/2005 11:47 AM

Re: NC Facilities Sugar Creek & Irwin Creek NPDES Li...
i • f f
Subject: Re: NC Facilities Sugar Creek & Irwin Creek NPDES Limits (Copper &
Zinc)
From: "Michael Montebello" <[e-mail]>
Date: Mon, 07 Feb 2005 10:02:19 -0500
To: <j ackie.nowell @ ncmail.net>
CC: "Jeff DeBessonet" <[e-mail]>, <[e-mail]>
Ms. Nowell,
I need some additional information on the hardness values used in
the formula's. The noted hardness is 85 mg/1 for Irwin Creek and 63
mg/1 for Sugar Creek. Is this the mixed hardness downstream (after
complete mixing with the receiving stream) or the effluent hardness
based on collected sampling data?
We would typically use the effluent hardness from collected effluent
data and assume a stream hardness of 25 mg/1 (based on our SC Water
Quality Standards). We also specify that a CCC be used as a chronic
value and a CMC be used as an acute value. In the case of Zinc the
CMC is lower than the CCC (due to the development of the standard)
so only a daily maximum is necessary.
This results in the following limits (that would be protective of SC
Water Quality Standards) for the noted facilities (based on the
assumptions above).
Irwin Creek (15 MGD)
Copper
Monthly Average (ug/1) 19.23
Daily Maximum (ug/1) 27.98
Zinc
Daily Maximum (ug/1)
284.18
Sugar Creek (20 MGD)
Copper
Monthly Average (ug/1) 14.62
Daily Maximum (ug/1) 20.83
Zinc
Daily Maximum (ug/1) 216.93
These values are somewhat lower than the proposed limits (primarily
due to the question on hardness).
If the hardness data is from the a downstream sampling location
(after complete mixing with the receiving stream) then I would need
to revise the values noted above. I could reproduce the proposed
effluent limits from the attachment assuming that the "mixed"
hardness was 85 mg/1 for Irwin and 63 mg/1 for Sugar Creek.
We would like to see any revised draft permit limits for these
1 of 2 2/7/2005 11:47 AM

Re: NC Facilities Sugar Creek & Irwin Creek NPDES Li...
permits if you make changes to the permits.
Thank You,
Mike Montebello
Michael Montebello, Manager
Domestic Wastewater Permitting Section
Phone [phone]
Fax [phone]
[e-mail]
Jackie Nowell <[e-mail]> 11/2/2004 2:51:59 PM
»>
Mike,
Attached is the information you requested. Permits highlighted in
Carolina Blue will have maps faxed to you.
Jackie Nowell
2 of 2 2/7/2005 11:47 AM

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Action Level Calculation (February 2004) 04/16/04
Metal
Copper
Zinc
Facility
Irwin Creek
Sugar Creek
Facility
NOTES:
Chronic AL
7
50
Acute AL 1/2 FAV Chronic CF
7.3 0.96
67 0.986
Acute CF
0.96
0.978
Kpo
1.04E+06
1.25E+06
alpha WQCdis(chrnc) WQCdis(ac)
-0.7436 6.72 7.008
-0.7038 49.3 65.526
Permit No. Flow 7Q10s IWC Subbasin TSS(15th ptcr Cu fD=cD/cT Zn fD=cD/cT
15 4.9 82.59 CTB34
20 3.4 90.12 CTB34
Permit No. Cu Limit Zn Limit
3 4.20E-01
3 4.20E-01
3.66E-01
3.66E-01
Cu C instrm Zn C instrm
•

Action Level Calculation {February
Metal Chronic AL
Copper 7
Zinc 50
Facility Permit No. Cu Ac Ins Zn Ac Inst
Irwin Creek 17 179
Sugar Creek 17 179
Facility Permit No.
NOTES:

•
(CM
CHARLOTTE..
1 CI
August 19, 2004
Jacquelyn M. Nowell
NPDES Unit
Division of Water Quality
North Carolina Department of
Environment and Natural Resources
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Re: NPDES Permits NCO24945 (Irwin Creek) and
NC0024937 (Sugar Creek)
Dear Ms. Nowell:
We are providing this information as a supplement to our July 1, 2004, letter to
Mark McIntire concerning water quality -based effluent limits (WQBELs) for the Irwin
Creek and Sugar Creek wastewater treatment plants ("WWTPs"). This letter sets forth
additional calculations for copper and zinc WQBELs factoring in TSS data -- as reflected
in the WQBEL permitting approach utilized by South Carolina Department of Health and
Environmental Control (DHEC) and identified in the DHEC correspondence from Mr.
Mike Montebello to you (provided to us by e-mail dated July 14, 2004). In light of the
fact that the effect of partitioning on total suspended solids to establish WQBELs for
metals is utilized by DHEC and would not be novel, we request that this approach, which
is also recommended by EPA, be utilized by DENR in the permitting of the Charlotte
Mecklenburg Utility ("CMU") WWTPs. As such, this letter sets forth revised WQBEL
calculations utilizing the TSS partitioning coefficients.
Mr. Montebello notes in his correspondence that, in the absence of actual stream
data, DHEC uses a background TSS of 1 mg/1— which is based on the 5th percentile of
ambient TSS data on South Carolina streams from 1993 — 2000. While we question and
reserve our right to challenge the use of the 5th percentile TSS concentration , as reflected
' Mr. Montebello also notes that DHEC uses a hardness of 25 mg/1 in the absence of actual effluent data or
based on the 10th percentile of actual effluent hardness data. To date, we have been unable to ascertain the
basis for using these specified percentiles in addition to the 7Q10 drought stream flow and the design
WWTP flow as the basis for establishing WQBELs. Neither of these approaches is required by applicable
South Carolina regulation or law. This combination of factors yields very restrictive effluent limitations
with a potential for exceedance much more remote than the once in three years upon which the water
quality standards for protection of aquatic life are based.
CHARLOTTE-MECKLENBURG UTILITIES
Environmental Management Division
4000 Westmont Drive
Charlotte, NC 28217
PH: 704/357-1344

by the enclosed calculations, the copper and zinc limits should significantly change such
that it may become a moot issue.
At design flow conditions used for establishing water quality -based effluent
limitations (e.g., WWTP design flow and 7Q10 stream flow), the stream contribution is
relatively minor and the background TSS concentration has little impact. Consistent with
the approach used in the TSD , the below calculations use the mean TSS for the effluent,
particularly in light of the fact that the combination of 7Q10 flow and design WWTP
flow already provides a very high degree of protection. These data are summarized in the
table below.
Statistical Evaluation of DMR TSS Performance Data
July 2001— June 2004
Parameter
Irwin Creek3
Sugar Creek4
Number of Observations
769
766
Mean
2.40 mg/1
2.44 mg/1
The data summarized above indicate that both facilities provide a very high
degree of treatment with average effluent TSS at 2.4 mg/1. The effluent exerts a
significant influence on the instream TSS because both WWTPs discharge to effluent
dominated streams. At drought conditions, the instream waste concentration (IWC) for
the Irwin Creek WWTP is 82.3 percents. The IWC for the Sugar Creek WWTP is 90.1
percent6. Even under the DHEC approach where the upstream flow in the receiving
water is assumed to have a background TSS of 1.0 mg/1 (e.g., the 5th percentile TSS
referenced by Mr. Montebello), the TSS after mixing would be 2.15 mg/1 for the Irwin
Creek WWTP and 2.30 mg/1 for the Sugar Creek WWTP.
These TSS concentrations, after mixing under design conditions, were used with
the partitioning coefficients identified in Mr. Montebello's correspondence to you to
2 The Technical Support Document for Water Quality -based Toxics Control (TSD; EPA, 1991)
recommends that secondary parameters, which influence toxicity, be established using EPA's DESCON
model. The model correlates these secondary parameters with flow to meet the once -in -three-year
exceedance frequency allowed by water quality criteria. If flow is not correlated with the secondary
parameter, the model will yield the mean concentration as the most appropriate for use in developing water
quality -based effluent limits.
3 The coefficient of variation, as determined using the delta log -normal statistical method in the TSD, was
0.56 indicating that the effluent TSS is not highly variable.
4 The coefficient of variation, as determined using the delta log -normal statistical method in the TSD, was
0.71 indicating that the effluent TSS is not highly variable.
5 The design conditions for the Irwin Creek WWTP are 15 MGD and 7Q10 = 4.9 cfs.
6 The design conditions for the Sugar Creek WWTP are 20 MGD and 7Q10 = 3.4 cfs.

•
calculate the dissolved fraction of each metal for use in calculating WQBELs for each
WWTP. The dissolved fractions (FD) for each metal are summarized below.
Dissolved Fractions Calculated from Partition Coefficients
Parameter
Irwin Creek WWTP
Sugar Creek WWTP
Total Suspended Solids
2.15 mg/1
2.30 mg/1
FD (copper)
0.441
0.437
FD (zinc)
; 0.389
0.385
These dissolved fractions should be used to calculate WQBELs for the total
recoverable forms of copper and zinc. As discussed in our previous letter, the appropriate
hardness for establishing WQBELs for these metals is 85 mg/1 for the Irwin Creek
WWTP and 63 mg/1 for the Sugar Creek WWTP. The appropriate WQBELs based on
these hardness values and dissolved fractions are summarized below.
Water Quality -Based Effluent Limits
Parameter
Irwin Creek
Sugar Creek
Copper
Zinc
Copper
Zinc
7Q10 Flow
4.9 cfs
3.4 cfs
WWTP Flow
15 MGD
20 MGD
Hardness
85 mg/1
63 mg/1
TSS
2.15 mg/1
2.15 mg/1
2.30 mg/1
2.30 mg/1
FD
0.441
0.389
0.437
0.385
WQS (dissolved)
11.53 1,tg/1
102.1 µg/1
8.70 41
79.2 µg/1
WLA (dissolved)
13.96 14/1
123.7 µg/1
9.66 µg/1
87.9 µg/1
WQBEL
(total recoverable)
31.6 4g/1
317.5 µg/1
22.1 1.41
228.4 µg/1
The critical condition for TSS partitioning occurs at the 7Q10 flows. As instream flows increase, the
calculated WQBELs would increase.

We hope that this analysis, fully consistent with the preferred WQBEL permitting
approach of DHEC, is helpful for the DENR development of WQBELs for the CMU
WWTPs. We will soon be contacting you to arrange a meeting so that we can resolve
any outstanding issues associated with the copper and zinc limits and to assure that
appropriate WQBELs are established.
Sincerely,
cqueline A. Jarrell, P.E.
Environmental Management Division Supt.
C: D. Padgett
B. Gullet
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July 1, 2004
Mark McIntire
NPDES Unit
Division of Water Quality
NCDENR
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Re: •NPDES Permits NCO24945 (Irwin Creek) and
NC0024937 (Sugar Creek)
Dear Mr. McIntire:
Thank you for your recent e-mail identifying the potential approach being
considered by the North Carolina Department of Environment and Natural Resources
("DENR") in developing water quality -based effluent limits ("WQBELs") for the
NPDES permits to be reissued to the Charlotte Mecklenburg Utilities ("CMU") Irwin
Creek and Sugar Creek wastewater treatment plants ("WWTPs"). CMU has concerns
associated with the underlying permitting approach that, as indicated in our telephone
conversations, is primarily based on DENR's desire to placate perceived preferences of
the South Carolina Department of Health and Environmental Control (DHEC). As such,
we request a meeting to discuss the underlying permitting issues and to explore ways of
assuring adequate protection of water quality without imposing overly restrictive
requirements upon CMU.
While we appreciate your latest e-mail and discussion we had over the phone,
shedding some light on the discussions between DENR and DHEC, CMU again requests
that you provide us copies of the written communications from South Carolina.
Although you have consistently indicated to us that you will immediately forward us the
documents, we have yet to receive the information.
Clean Water Act Requires Effluent Limitations Necessary to Meet State Water
Quality Standards
The Clean Water Act requires only that a discharger meet effluent limitations
"necessary" to meet State water quality standards. See, e.g., CWA Section 301 (b)(1 )(C).
' See also 40 C.F.R. 122.44(dx1) ("[Ejach NPDES permit shall include conditions meeting the following
requirement when applicable ... (d)(1) "Water quality standards and State requirements: any
requirements in addition to or more stringent than promulgated effluent limitations guidelines or standards
CHggL��e__ss__a__r�yr to achieve water quality standards .... ")
trE M CKLENBURG UTILITIES
Environmental Management Division
4000 Westmont Drive
Charlotte, NC 28217
PH• 7041357.1344

It does not require a discharger to meet limitations more stringent than that necessary to
meet water quality standards. As discussed below, the NPDES permitting approach
being espoused by South Carolina and being considered by the DENR provides for the
development of effluent limitations much more stringent than that necessary to protect
water quality standards. Such approach is simply arbitrary.
The federal NPDES regulations identify what standards apply in the NPDES
permitting context. State permitting policies, as a matter of law, are not applicable, much
less South Carolina's unwritten, undocumented, and arbitrary ninety percent hardness
approach that they are informally asking DENR to impose. An "applicable requirement"
for a State issued NPDES permit is a "State statutory or regulatory requirement which
takes effect prior to final administrative disposition of the permit." 40 C.F.R. Section
122.43(b)(1).2
South Carolina has pointed to no State statute or regulation in its water quality
standards requiring the imposition of an ultra -conservative ninety -percent hardness value3
for developing water quality -based effluent limitations. If South Carolina was the
permitting agency and sought to impose such an off-the-cuff standard upon CMU, we
would be challenging such approach and would fully expect to prevail on the challenge.4
Surely the fact that South Carolina is asking North Carolina to use its unsupportable
approach makes it no more legal.
The following comments and analysis addresses the primary issues associated
with the proposed approach to use a ninety -percent hardness value which is irreconcilable
with the modeling of the WQBELs based upon 7Q10 historic low flows.
Evaluation of Draft WOBELs
2 Similarly, EPA's authority to object to a North Carolina issued NPDES permit effluent limitations would
need to be based upon the failure of the permit "to ensure compliance with applicable requirements" (40
C.F.R. § 123.44(c)(1)), findings made by the State misinterpreting the CWA, guidelines or regulations, or
misapplying them to the facts (§ 123.44(c)(4)) or the effluent limits fail to satisfy the requirements of §
122.44(d)." As demonstrated below, none of these conditions exist. Correspondence from EPA
Headquarters clearly reflects that, among other things, NPDES permits using the hardness corresponding to
the low -flow modeling conditions is appropriate and fully complies with the Clean Water Act and
implementing regulations.
3 In your latest e-mail you refer to it as the "10t percentile." This letter uses the term "90t percentile" to
refer to what your June 4, 2004, e-mail is now referring to as the "10t percentile" and uses the term "99`h
percentile" to refer to what you e-mail refers to as the "1St-percentile."
" Even if South Carolina were somehow deemed to have the requisite discretion to use a ninety -percent
hardness value when it issues an NPDES permit, such discretionary authority does not make it mandatory
for an upstream state to use such approach when it is the permit issuing authority. The only issue to be
demonstrated is whether a specific discharge level will cause a violation in another state, not does the other
state calculate effluent limits more conservatively.
2

The prior draft NPDES permits for Irwin Creek and Sugar Creek contained
WQBELs for copper, zinc and silvers based upon the 99th percentile hardness data. This
value, as communicated by DENR to CMU, was, as we were told by your predecessor,
based upon South Carolina DHEC communicating to DENR that state requirements
provided for the 99th percentile. You have indicated to us that that recent communication
from DENR to CMU now indicates that the 90th percentile for hardness to be the
percentile required by South Carolina requirements.6 As further discussed below, the
hardness to be used is that reflective of the receiving water during low flow conditions. 7
The EPA water quality criteria, incorporated by reference by South Carolina
regulation include an exceedance frequency of once in three years in addition to the
magnitude of exposure and the duration of exposure.8 Thus, designated uses of the
receiving stream, such as maintenance of a balanced indigenous aquatic community, are
achieved if the receiving stream does not exceed the numeric water quality criteria more
frequently than once in three years on average. However, the exceedance frequency was
not appropriately considered by DHEC (or DENR) when the critical conditions for the
WQBELs were established.
The WQBELs were determined for drought stream flow conditions (i.e., 7Q10
stream flow) and the permitted treatment plant flow. DENR now proposes to base the
WQBELs for copper and zinc on the 90th percentile lowest hardness concentration for the
receiving stream (58 mg/1 for Irwin Creek and 51.6 mg/1 for Little Sugar Creek). The
combination of drought stream flow and 90th percentile low hardness represents an
5 DENR informed us that the proposed WQBELs for silver will be deleted from the permit. As such, this
discussion focuses only on zinc and copper. The concerns, however, would be equally applicable to silver.
6 The change in the percentile being asked for by South Carolina is indicative of the fact that there is no
such legal requirement. Our consultant William Hall from Hall & Associates, Washington, D.C. spoke to
Mr. Montebello and Ms. Vickers of DHEC and was informed by them that South Carolina does not have
regulations, guidance, or policy requiring the use of the 90th percentile. In contrast, Section 61-68.E.12 of
DHEC regulations indicates that it specifically incorporates by reference the EPA criteria. These criteria,
as acknowledged by EPA Headquarters do not require the use of the 90t percentile.
7 In our recent telephone conversation you indicated that an e-mail from South Carolina asserts that Section
61-68.E.12.a.(3) requires the use of the 90th percentile. A review of the regulation indicates that nowhere
does such regulation impose a 90th percentile requirement but instead, where hardness is between 25 mg/1
and 400 mg/1, the actual mixed stream hardness would be used. The regulation states:
If metals concentrations for numeric criteria are hardness -dependent, the CMC and CCC
concentrations shall be based on 25 milligrams/liter (mg/1) hardness (as expressed as
CaCO3) if the ambient hardness is less than 25 mg/I. Concentrations of hardness less
than 400 mg/1 maybe based on the actual mixed stream hardness if it is greater than 25
mg/1 and less than 400 mg/I and 400 mg/I if the ambient hardness is greater than 400
mg/l.
8 See US EPA, Ambient Water Quality Criteria for Copper — 1984, EPA 440/5-84-031 (1985) at 23; US
EPA, Ambient Water Quality Criteria for Zinc —1987, EPA 440/5-87-003 (1987) at 32. See also US EPA,
Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic
Organisms and Their Uses, NTIS PB 85-227049 (1985) at 55; 40 § 131.36(c)(2)(ii) (description of "CMC"
and "CCC").
3

•
extremely rare (if not impossible) event that has a recurrence frequency much less than
once in three years. Consequently, this approach results in extremely conservative
effluent limits that have no relationship to meeting applicable water quality standards.
Guidance on the appropriate hardness to use with the drought flow condition is
available from EPA in the Technical Support Document for Water Quality -based Toxics
Control, EPA/505/2-90-001 (1991) at 79 (commonly referred to as "TSD") and in the
Technical Guidance on Supplementary Stream Design Conditions for Steady State
Modeling (EPA, 1988). With regard to establishing waste load allocations (WLAs) using
a steady-state modeling approach (as used by the South Carolina DHEC), the TSD notes
that the "frequency and duration of ambient conditions predicted with a steady-state
model must be assumed to equal the frequency and duration of the critical receiving
water conditions used in the model." (TSD at 78-79). In order to meet the "once in three
year" return frequency specified for the water quality criteria, the 7Q10 (drought flow)
condition is used. EPA has determined that the 7Q10 already accounts for the "once in
three year" exceedance frequency (TSD at 79). Preamble to EPA regulations also
recognizes that use of the 7Q10 flow, without any additional conservative assumptions,
provides the requisite degree of protection. See, e.g., 57 Fed. Reg. 60880 (1992) ("The
three-year return interval approximates the same degree of protection as a once -in -ten-
year seven-day average low flow design condition (7Q10).")
The TSD goes on to note that steady-state models require design conditions for a
parameter such as hardness (which affects the toxicity of certain metals). Ordinarily, the
attainment of water quality goals does not require setting these multiple parameter values
at worst -case conditions (see Delos, 2000, Enclosed).9 Instead, the hardness of the
receiving water at critical flow conditions is to be used.10 A prime example of using the
corresponding receiving water hardness is reflected in the EPA computer program
DESCON which is used to determine the appropriate design conditions while fully
assuring that the calculated WLA would meet the appropriate exceedance frequency.
DESCON specifically accounts for correlations between variables such as stream flow
and hardness to derive the appropriate design condition.
9 Letter from Charles Delos, EPA to William T. Hall, Hall & Associates, October 12, 2000 at 1 ("Delos
Letter") ("The TSD supports the use of correlation analysis" and "[o]rdinarily the attainment of water
quality goals does not require setting multiple parameter values at worst case values.")
1° See, e.g., 40 C.F.R. § 131.36(c)(4)(ii) ("The hardness values used shall be consistent with the design
discharge conditions ... for flows.... "); Delos Letter at 2 ("If hardness is inversely correlated with flow,
then coupling low hardness with low flow would be expected to yield more protection than is intended for
the criteria or necessary for attainment of goals" and "it is appropriate to assign parameter values that could
likely occur under low flow conditions.") See also US EPA, The Metals Translator: Guidance for
Calculating a Total Recoverable Permit Limit from a Dissolved Criterion, EPA 823-B-96-007 (1996) at 12
("Considerations of Appropriate Design Flow Conditions for Metals .... If one were to collect samples of
... hardness... over a prolonged period (i.e., several years) then one could examine the data set to
determine which combination of conditions would result in the highest dissolved metal concentration for a
'unit load' of metal in the effluent stream. The flow regime associated with this critical condition would
constitute the design flow.")

•
The available data for Irwin Creek and Little Sugar Creek can be used to correlate
hardness with stream flow to demonstrate that it is not appropriate to use an arbitrarily
selected percentile lowest hardness concentration as the basis for establishing WQBELs.
These correlations can also be used to identify the appropriate hardness expected to occur
with the 7Q10 stream flow.
Hardness Correlation with Stream Flow
Hardness data, collected by the North Carolina DENR and by CMU, were
correlated with stream flows monitored by the USGS to evaluate whether the design
hardness values prescribed by the South Carolina DHEC were overly conservative. The
data set for these correlations is illustrated in the Appendix A (Hardness Data and
Correlation with Stream Flow).
• Irwin Creek WWTP
For the Irwin Creek WWTP, daily stream flow data for USGS Station 02146381
(Sugar Creek at NC 51 near Pineville, NC) was correlated with hardness data from the
NC DENR Station C9050000 and CMU Station SC4 (both stations are located on Sugar
Creek at NC 51). The hardness data collected by the DENR for Station C9050000 was
for the period from January 1995 through August 2000. DENR ceased collecting water
quality data at this station after August 2000. Subsequently, CMU initiated collection of
hardness data at this same location, now designated as Station SC4, for the period from
November 2002 through March 2004. The correlation between flow and hardness for
Sugar Creek, downstream from the Irwin Creek WWTP is illustrated in Figure 1 under
low flow conditions (i.e., flows less than 100 cfs).
Figure 1
140
120
100
51
E 80
a
v60
x
40
20
0
Sugar Creek at NC 51 near Pineville, NC
•
• •
•
•
♦
•
• ♦• ••
.♦ :_..... _•_1
♦
t
•
•
•
:♦ ♦♦•♦ ♦ :♦
♦ ♦_•
♦ ♦ ♦
•
♦
♦
••
•♦
♦ ♦ •
•-•
•
0
10 20 30 40 50 60
Sugar Creek Flow (ds)
70
80
90
DENR is now proposing to use a design hardness of 58 mg/1 to calculate copper
and zinc WQBELs for the Irwin Creek WWTP. The following analysis uses a design
100
5

flow of 28.1 cfs (7Q10 = 4.9 cfs; WWTP = 15 MGD).11 Figure 1 indicates that the
instream hardness rises well above 80 mg/1 as the stream flow decreases from 100 cfs to
the 7Q10 drought flow condition. Thus, it is apparent that the selected design hardness
concentration is unnecessarily restrictive.
• Sugar Creek WWTP
For the Sugar Creek WWTP, daily stream flow data for USGS Station 02146530
(Little Sugar Creek at NC 521 at Pineville, NC) was correlated with hardness data from
the NC DENR Station C9210000 and CMU Station LSC3 (both stations are located on
Little Sugar Creek at NC 521). The hardness data collected by the DENR for Station
C9210000 was for the period from July 1997 through August 2000. DENR ceased
collecting water quality data at this station after August 2000. Subsequently, CMU
initiated collection of hardness data at this same location, now designated as Station
LSC3, for the period from November 2002 through March 2004. The correlation
between flow and hardness for Little Sugar Creek, downstream from the Sugar Creek
WWTP is illustrated in Figure 2 under low flow conditions (i.e., flows under 100 cfs).
DENR is now proposing to use a design hardness of 51.6 mg/1 to establish copper
and zinc WQBELs for the Sugar Creek WWTP. The following analysis is based on a
design flow of 34.3 cfs (7Q10 = 3.4 cfs; WWTP = 20 MGD).12 Figure 2 indicates that
the typical instream hardness rises well above 60 mg/1 as the stream flow decreases from
100 cfs to the 7Q10 drought flow condition. Therefore, it is apparent that the selected
design hardness concentration is unnecessarily restrictive.
Figure 2
120
100
80
E
60
e
s
a
40
20
0
Little Sugar Creek at NC 521 at Pineville, NC
♦
♦
♦ ♦♦
♦
•
•
♦
•
• 1 •
♦• •♦
♦♦♦
•♦♦
♦
••
♦
•♦
♦
•
•
♦♦♦
♦•
♦
♦
•
•
•♦♦
♦
10 20 30 40 50 60
Little Sugar Creek Flow (cis)
70
80
90
100
11 The instream waste concentration ("IWC") used in the May 29, 2004, DENR calculations is 83.2%. As
discussed below in the subsection titled "Instream Waste Concentration," the IWC should be 82.57%.
I Again, there is a small correction to be made to the IWC. As discussed below, the IWC used in the May
29, 2004, DENR calculation is 90.9% whereas it should be 90.099%.
6

Evaluation of Appropriate Design Hardness
As discussed above, Figure 1 and Figure 2 present information to be used to
establish an appropriate hardness value for developing effluent limitations for the Irwin
Creek and Sugar Creek WWTPs to better approximate the once -in -three-year excursion
frequency that meets applicable water quality standards. As noted previously, EPA
already considers use of the 7Q10 as being a very conservative approach that, in and of
itself, provides for the once -in -three-year excursion. Furthermore, the WQBELs are
being derived by assuming that the effluent concentration will be at its highest levels
when the stream flow is at its lowest. However, a review of each facility's performance
data (See Appendix C) demonstrates that the typical discharge concentration to be much
lower. The combination of these two conditions (i.e., drought flow and discharge
effluent concentration at its highest levels) is sufficiently conservative to ensure
compliance with the authorized return frequency. Consequently, the hardness should be
set at an average concentration expected to occur when the stream is at drought flow.
• Irwin Creek WWTP
The hardness and stream flow data for the Irwin Creek WWTP were sorted by
stream flow and the hardness data were evaluated using a running average and running
median to characterize the typical hardness expected at these flows. The results of this
analysis are presented in Figure 3.
The running average or running median hardness represents the typical hardness
expected when the stream flow is equal to or less than the flow indicated on the figure.
Thus, the typical hardness upon which the permit for Irwin Creek should be based is 85
mg/1 at the design flow of 28.1 cfs. The typical hardness is greater than 80 mg/1 for
stream flows up to 84 cfs.
Figure 3
• Sugar Creek WWTP
7

i
Hardness (mg/l)
120
100
60
40
20
Sugar Creek at NC 51 near Pineville, NC
Typical Hardness
____oaa .o e_11 ei-am—a—e—e—
♦ Running Average
o Running Median
O 10 20 30 40 50 60 70 80 90 100
Stream Flow (cfs)
A similar evaluation was prepared for the Sugar Creek WWTP and is presented in
Figure 4.
Figure 4
120
100
80
E
• 60
c
co
= 40
20
0
Little Sugar Creek at NC 521 at Pineville, NC
Typical Hardness
Apse &Asa ea ate aes
a a
a
as
e8
• Running Average
o Running Median
O 10 20 30 40 50 60
Stream Flow (cfs)
70
80
90
100
The typical hardness upon which the permit for Irwin Creek should be based is 63
mg/1 at the design flow of 34.3 cfs. In this stream, the hardness slightly increases to 66
mg/1 as the flow increases to 50 cfs.
Revised Permit Limits for Typical Hardness
8

Appropriate water quality based effluent limits for the Irwin Creek and Sugar
Creek WWTPs, based on the typical hardness expected to occur under design conditions,
are summarized in the table below.
Parameter
Irwin Creek
Sugar Creek
Stream Flow (cfs)
4.9
3.4
WWTP Flow (MGD)
15
20
Hardness (mg/1)
85
63
Copper Limits (µg/1)
Acute
14.6
10.1
Chronic
9.8
7.0
Zinc Limits (4/1)
Acute
126.4
89.9
Reasonable Potential Evaluation
As indicated below, CMU's discharge of zinc from the Irwin Creek and Sugar
Creek WWTPs cannot reasonably be determined to exceed the revised WQBELs These
data are illustrated on statistical distribution graphs in the Appendix C (Statistical
Distribution Charts) and are summarized below.
Summary of Performance Data for Zinc
Statistic
Irwin Creek
Sugar Creek
Observations
84
84
Maximum Observed
110 µg/1
75141
99th Percentile Predicted
110.4 µg/1
70.7 µg/1
Mean
55.8 14/1
36.5141
WQBEL
126.4 µg/1
89.9 µg/1
Observations exceeding
WQBEL
0
0
In light of the fact that there is no reasonable potential for CMU to exceed the
revised WQBELs, effluent limitations for zinc should be deleted from the Irwin Creek
and Sugar Creek NPDES permits.
CMU Intent to Undertake A Water Effects Ratio Study for Copper
9

Due to the inability of CMU to meet the copper WQBELs, it intends to undertake
a water effect ratio (WER) study for both the Irwin Creek and Sugar Creek WWTPs
demonstrating that the copper limits should be higher. As such, CMU would like to
develop a study protocol in conjunction with DENR and DHEC to assure that any
applicable requirements of both agencies are appropriately being addressed. To provide
CMU the appropriate amount of time to undertake a WER study and to avoid the
contentious nature of the otherwise proposed effluent limits for copper that would
otherwise result, we request that DENR issue CMU permits for both the Irwin Creek and
Sugar Creek WWTP which do not include copper limits but instead requires a WER
study and includes a permit reopener to address the results of the study. The permits can
be short-term permits, which can get CMU back on the prior permit issuance cycle, or
long term permits, as DENR deems appropriate to accomplish such objective.
May 29, 2004 Calculations
Your June 4, 2004, e-mail contained a document titled "Effluent Limitations
Summary for Copper and Zinc, Division of Water Quality, May 29, 2004." The
following discussions regarding hardness, mixing and instream waste concentration
pertain to the analysis set forth in the May 29, 2004, analysis. While the impact to the
CMU WQBELs is not as great as that associated with the above issues, the requested
corrections provide for further adjustment of the proposed WQBELs.
Hardness Used In DENR May 29, 2004 Calculations
Notwithstanding CMU's disagreement with the use of the 90th percentile
hardness, we want to point out that the DNREC calculations failed to account for the
CMU data.
The effluent limits for Irwin Creek were based on a 901h percentile hardness of 58
mg/1 from a review of 155 observations in the 17-year period of record. The record
begins in February 1983 and ends in December 2000. CMU, however, initiated
collection of hardness data in November 2002 continuing to April 2004. With the
additional 23 observations included in the record, the revised 901h percentile hardness is
60 mg/1.13
Note that these calculations ignore the design conditions used to establish effluent
limitations. The actual hardness expected when the receiving streams are at drought flow
is significantly higher than the 90th percentile hardness.
Mixing Assumptions Used in May 29, 2004 DENR Analysis
Your June 4, 2004, e-mail states "For acute limits, we are protecting for end -of -
pipe impacts during a short-term exposure period. During that period, complete mixing
13 The data set for Sugar Creek should also be updated to include the 23 sampling results obtained by CMU
between November 2002 and April 2004 (although such data would not impact the 90th percentile
calculation.)
10

f
will not have occurred thus we do not account for dilution in establishing acute limits."
Complete mixing, however, depends upon a number of factors that are independent of the
permit averaging period. These factors include discharge -induced mixing, river width,
velocity of flow, water depth, and slope (see TSD @ 77). Given that the effluent flow
accounts for over 80 percent of the total flow under design conditions, mixing is
generally deemed complete for the purposes of evaluating acute toxicity due to discharge -
induced mixing. This can be confirmed by site -specific testing or by modeling.
Alternatively, EPA's TSD provides a very conservative model that could be used
to determine whether mixing is complete when the flow reaches the waters of South
Carolina, which are located more than a mile downstream in each case. The TSD notes
that, for very small streams, the distance to complete mixing is often only a few hundred
feet (TSD @ 77). This situation is most likely the case for both Irwin Creek and Sugar
Creek.
Consequently, effluent limits should have been calculated with consideration for
mixing rather than as end -of -pipe limits without mixing.
Instream Waste Concentration Used in DENR May 29, 2004 Analysis
The Effluent Limitation Summary for Irwin Creek, provided in the May 29th
analysis indicates that the instream waste concentration (IWC) for the Irwin Creek
WWTP is 83.2 percent. The fact sheet with the draft permit, dated July 11, 2003,
identifies the summer 7Q10 flow in Irwin Creek as 4.9 cfs and the design permit flow for
the Irwin Creek WWTP as 15 MGD (23.205 cfs). Together, these conditions yield a total
flow of 28.105 cfs and an IWC of 82.57%. This IWC, which is less restrictive than that
used to develop Irwin Creek's effluent limits, should be the values used to develop
WQBELs.
Similarly, the Effluent Limitation Summary for Sugar Creek provided as an
attachment to Mr. McIntire's e-mail indicates that the IWC for the Sugar Creek WWTP is
90.9 percent. The fact sheet with the draft permit, dated July 11, 2003, identifies the
summer 7Q10 flow in Little Sugar Creek as 3.4 cfs and the design permit flow for the
Sugar Creek WWTP as 20 MGD (30.94 cfs). Together, these conditions yield a total
flow of 34.34 cfs and an IWC of 90.099%. This IWC, which is less restrictive than that
used to develop Sugar Creek's effluent limits, should be the values used to develop
WQBELs.
CMU further note that Little Sugar Creek flows several miles from the Sugar
Creek WWTP discharge before the flow enters South Carolina. Similarly, Irwin Creek
flows into Sugar Creek before the combined flow enters South Carolina. Any additional
dilution provided by the drainage area prior to entering South Carolina waters should be
considered in deriving the IWC for metals limits intended to meet South Carolina's water
quality standards.
11

CMU appreciates the opportunity to address these issues with you. Establishing
copper and zinc limits for the CMU facilities that fully protects water quality but avoids
the unnecessary expenditure of limited municipal resources is important to us. As such, it
is imperative that there be open and candid dialogue between the various interested
governmental entities. As such, we request a meeting to discuss these important issues
with the objective of reaching agreement on these important permitting matters.
will soon give you a call to set up a meeting.
Enclosure
C: D. Padgett
B. Gullet
file
4cquene k. • A
A. Jarrell, P.
Environmental Management Division Supt.
Sincerely,
12

Appendix A
Hardness Data and Correlation with Stream Flow

140
120
100
a0
40
20
0
Sugar Crook at NC 51 near Pineville, NC
•
-
•
•
♦
• •
••
•
•
• •
•
•
••9
•
M
•41
•
•
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::
•
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-
•
•
•
• •
•,
•
•
,
.•
•
•♦
•
•
• •
•
'
•
•
•
~
1011/94
140
120
100
40
20
0
1011195
Of30/96
9130/97
10/119a
10V1/99
Date
9rs0f00
Sugar Creek at NC 51 near Pineville, NC
9130/01
101/02 10/1/03
••
•
•
i • •
f•
•
•••
•
•
0
100
200 300 400
Super CreaL Flom (trial
500
600
700

c
1
120
Little Sugar Creek at NC 521 at Pineville, NC
100• • • •
•
20
•
• •
•
•
I
• •• • ••
• • •
• • • • •.•
.• —
•
•
•• •
•
so
•
• ••
• ire
• •
•
1/1/97 11119a 111199 111100 1/1/01 1/1102 1/1/03 111/04
Cava
120
100
20
0
Little Sugar Creek at NC 521 at Pineville, NC
•♦•
•
4•
t •
•44•
t
•
•
•
•
•
•
•
0
100
200 300
Little Super Creek Flo. (oh)
400
600

Appendix B
Stream Flow — WWTP Flow Correlation

20
18
16
14
0
2 12
t 10
6
4
2
Sugar Creek Flow versus Irwin Creek WWTP Flow
•
..
•
•
r r r
0 50 100 150 200 260 300 350 400 450 500
20 -
19
16
a 14 •
0
12
8 10 •
6
Sugar Cask (cis)
Little Sugar Creek How versus Sugar Creek WWTP Flow
•
•
•
.
••
•
•
4•
2.
a
0
50 100
150 200 250 300 350 400 450 500
Unto Sugar Croak (cfs)

t * •
Appendix C
Statistical Distribution Charts

tlb
100
a 10
0
N
Irwin Creek POTW DMR
(December 2002 - March 2004)
Oats
Loa -Normal Model
•
•
•2.5
1000
100
•2 0 -1.5
-1 0 •0 5 0 0 0 5 1.0
Standard Deviation
Irwin Creek POTW DMR Data
(December 2002 - March 2004)
15 20 25
• Osie
lop -Norms! Mod.!
10 1
•2 $
• • 1 •
.20 .1.5 • 1 0 O5 0.0 0.6 1.0 1.6 2.0 26
Standard Devladon

• •
c1
c
N
100
Sugar Creek POTW DMR Data
(December 2002 - March 2004)
• Da
Log -Normal Model
•
1 . + l 4
-2 5 -2.0 -1.5 .1 0 -0 5 0.0 0 6 I.0 1 5 2.0 2.5
Standard Deviation
100
10
Sugar Creek POTW DMR Data
(December 2002 - March 2004)
L00•Normtl Mogul
•2.5
•
1 1 ♦ 6 • 1 1 • 1
.20 •1.5 40 .0.6 0.0 05 1.0 15 20 21
Standard Deviation

d4D !Prot..,
14:1,ZZ,
Mt
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
OFFICE OF
WATER
October 12, 2000
Mr. William T. Hall
Hall & Associates
1101 15`h Street, NW
Washington, DC 20005-5007
Dear Mr. Hall:
This is in response to your September 6 letter about water quality criteria implementation through
steady-state WLA analyses. You have asked several closely related questions about EPA
recommendations on steady-state input values for critena that are expressed as formulas involving
another water quality parameter.
Before addressing the specific questions, 1 need to point out that the implementation of standards
within a state must follow the requirements of the regulations of that state, irrespective of whether
the mandatory provisions of those regulations accord with the non -binding recommendations of
EPA guidance.
In the answers below, I have responded with my understanding of the technical issues involved,
and of EPA's guidance thereon. From EPA's point of view, however, States are completely free
to implement criteria in a manner that is more stringent than EPA believes to be necessary for the
attainment of water quality goals..
Question 1. Does the TSD support the use of correlation analyses to establish appropriate
critical conditions for steady-state modeling or does the TSD recommend the use of "worst
case" conditions for all relevant model input parameters?
Response. The TSD supports the use of correlation analysis for both steady-state and time -
variable modeling. On page 79, the TSD recommends using the computer program DESCON for
obtaining steady-state WLA modeling design parameters. This program specifically accounts for
the within -year correlations observed between such variables as stream flow, temperature, pH,
alkalinity, hardness, and dissolved oxygen.
Ordinarily the attainment of water quality goals does not require setting multiple parameter values
at worst case values. I am not aware of the TSD anywhere recommending the simultaneous use
of "worst case" values for all model parameters.

R > >
Question 2. When higher hardness is correlared to low stream flow, .is it appropriate to apply
the minimum hardness as the basis for hardness -dependent water quality standards in the
steady-state model?
Response. In most (but not necessarily all) situations, the general expectation is that higher
hardness would accompany lower flow, because under low flow conditions groundwater input
would comprise a substantially greater fraction of the streamflow than it would at higher flows. If
hardness is inversely correlated with flow, then coupling low hardness with low flow would be
expected to yield more protection than is intended for the criteria or necessary for attainment of
goals.
The answer to this question is closely related to that of Item #l. For many years it has been
considered appropriate to assign parameter values that could likely occur under low flow
conditions, for example, as recommended in Technical Guidance Manual for Performing Waste
Load Allocations, Simplified Analytical Method.
Question 3- Does EPA recommend applying the highest observed in -stream pH value to
establish chronic water quality -based effluent limits for ammonia, based on the 1999 EPA
Update, when the highest in -stream pH is not correlated with drought stream flow conditions?
Response. For the condition described in the question, I am not aware of EPA having made that
type of recommendation. As discussed in the Technical Guidance Manual for Performing
Wasteload Allocations, Simplified Analytical Method (page A-11), the pH expected under design
flow conditions should be used. If adequate data are available, the guidance specifically
recommends against using the maximum observed pH (page A-13).
Technically the situation underlying any relationship between pH and flow seems a bit more
complicated than that underlying the relationship between hardness and flow. Under natural
conditions, absence of runoff during.low flow would lead to an expectation of higher pH under
such conditions. However, because municipal wastewater effluents tend to have relatively low
pH, the presence of greater fractions of municipal wastewater under low flow conditions would
tend to depress the pH.
In any case, however, it can be said that if pH and flow vary independently of each other, and if
you couple the rare critical pH event with the rare low -flow event, you end up with a condition
that is substantially More unusual than either the pH event or the flow event.
However, for discharges to ephemeral streams (that is, in effluent -dependent situations), a zero
upstream design _flow does not correspond to a rare event, but to .a common event. In this case,
pH, not flow, should be viewed as the critical design.pararneter, with its value selected to
correspond to a low frequency of occurrence.
I should also add here that we have been having some discussions about the selection of ammonia
criteria design pH in light of the 30-day chronic averaging period recommended in the 1999
2

Update of Ambient Water Quality Criteria. for Ammonia. For the chronic ammonia criterion, the
selected pH condition should reflect the 30-day averaging period. Thirty -day values are less
variable (less extreme) than grab sample values.
Question 4. Should the ammonia toxicity evaluation consider the effect of the effluent pH on in -
stream conditions after mixing when establishing water quality -based effluent limits? . .
Response. The evaluation should consider the effect of the effluent on the downstream segment
where the criterion is being applied. This pertains to pH, temperature, hardness, water -effect
ratio, and any other parameter on which the critenon depends. Depending on the characteristics
of the effluent and upstream waters, and the relationship between the parameter and the criterion,
accounting for the influence of the effluent may either raise or lower the criterion concentration.
Consequently in order to assure the appropriate level of protection, neither over nor under, it is
necessary to consider the downstream conditions.
The Technical Guidance Manual for Performing Wasreload Allocations, Simplified Analytical
Method (page A-11) specifically indicates that the downstream pH, after mixing, should be used
in the ammonia criterion calculation.
Question 5_ If no mixing zone is authorized or available, should the model utilize the pH of the
effluent or the pH of the up -stream water supply?
Response. If the criterion is expressed in terms of other water quality parameters, the appropriate
level of protection can only be assured if those water quality parameters have been reasonably
specified for the waters to which the criterion is being applied. At indicated in the previous
answers, the downstream pH should be used. If there is no mixing because of the absence of
upstream dilution water, the effluent pH should be used. If a mixing zone is not authorized even
though dilution is available, the analysis should still use the effluent pH; however, the analysis
should also confirm that once mixing does physically occur, standards will still be achieved.
Question 6. Is it appropriate to establish model assumptions for pH and hardness as permit
conditions to ensure compliance with water quality standards (e.g., establish a maximum effluent
pH limit or limit. the minimum hardness of the effluent) ?
Response. EPA has not historically recommended that model assumptions necessarily be
established as permit limitations. If the steady-state model inputs have been specified
appropriately, it is probably not necessary to do this.
Nevertheless, that does not mean.that some sort of pH or hardness limitation could not be
appropriately incorporated. However, it would not necessarily be appropriate to impose the pH
or hardness limitation as a freestanding limit, because violation of those limits by themselves
would not yield a water quality problem. Rather, the water quality problem results from a
combination elevated ammonia and elevated pH, or elevated metals and depressed hardness.
Consequently, technically it could make some sense, for example, to create a table of values such
3

that when the ammonia concentration equals the value in say Column A, the pH must not exceed
the value in Column B. Alternatively, pH could be treated as the independent variable, and
ammonia the dependent not -to -exceed -value. Nevertheless, there may be practical reasons for not
entertaining such an approach.
If you have further questions on the above responses, do not hesitate to contact me at
[e-mail] or at 202-260-7039.
Sincerely,
Charles Delos
Environmental Scientist
4

. •_
•
REASONABLE POTENTIAL ANALYSIS
CMU- Irwin Creek WWTP
NC0024945
Time Period 07 2001-07 2003
Ow (MGD) 15
7Q10S (cfs) 4.9
7010W (cfs) 7.7
3002 (cfs) 9.9
Avg. Stream Flow, OA (cfs) 43
Rec'ving Stream Irwin Creek
WWTP Class iV
IWC (%) ® 7Q10S 82.593
® 7010W 75.121
® 30Q2 70.136
® QA 35.094
Stream Class C
Outfall 001
Qw =15 MGD
PARAMETER
TYPE
Ili
STANDARDS &
CRITERIA (2)
PQL
Units
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
NCWQS/
Chnteek
II FAV/
Acute
n
SD.L Max Prod Or Allowzbl.Cr
Arsenic
NC
50
ug/L
0
0
NIA
Acute: N/A
I Chronic: �61---------•—•-----------------------
Beryllium
C
6.5
ug/L
0
0
N/A
Acute: N/A
Cadmium
NC
2
15
ugll.
0
0
WA
Acute: 15
• Chronic:.—.2 -------------
---------------------
Chromium
NC
50
1,022
ug/L
0
0
N/A
Acute: 1,022
_ _ .____----------------------------•—•—•—
Chronic: 61
Copper
NC
7
AL
7.3
uglL
115
115
23.8
Acute: 7
_ _--___---_•—•—___—•—•—•--_-_-_-_-__—_—__
Chronic: 8
Cyanide
NC
5
N
22
10
ugl.
0
0
WA
I Acute: 22
_ _ _—___---_.—_—__.—._•—.--____—_--__—_—_—
Chronic: 6
Fluoride
NC
1,800
ugIL
0
0
WA
Acute: WA
__ _ - _ _—•---_-------------------•----_--
Chronlc: 2,179
Lead
NC
25
N
33.8
ug/L.
0
0
WA.____--_—•_•-----------------_---------
Acute: 34
Chronlc: 30
Mercury
NC
0.012
0.0002
ug/L
0
0
Acute: WA
WA _ _ --___—
Chronic: 0
_-_--•-----------------•—•-----
Molybdenum
A
3.500
ug/L
0
0
N/A
Acute: WA
__ _
Chronic: 4,990
—_—___—____.—.—.—.—.—.—.—.—.—_—__
Nickel
NC
88
261
ug/L
0
0
WA
Acute: 261
_ _ -_ _ _-----•—•---------------_---------
Chronic: 107
Phenols
A
1
N
ugfL
0
0
WA
Acute: WA
Chronic: 1
Setenium
NC
5.0
56
ugfL
0
0
N/A
Acute: 56
_.—___----•_---__—_—_—•—•—_—__.—•_•__—__
Chronic: 6
Silver
NC
0.06
AL
1.23
ugll
115
0
N/A
Acute: 1
_ ______--_---__•—_---_—__--_—_—__--•—•—•_
Chronic: 0
Zinc
NC
50
AL
67
ug/L
115
115
157.3
Acute: 67
Chronic:---81•------------------------
------- -
Legend:
C = Carcinogenic
NC = Non -carcinogenic
A = Aesthetic
" Freshwater Discharge
trwtnCr04run,rpa
6/3/2004

Facility Name =
NPDES # =
Qw (MGD) =
7Q10s (cfs)=
IWC (%) =
CMUD - Irwin Creek
NC0024945
15
9.3
71.43
FINAL RESULTS
Silver
Max. Pred Cw
Allowable Cw
5.69
0.08
RESULTS
Std Dev.
Mean
C.V.
Number
of data points
Mult Factor =
Max. Value
Max. Pred Cw
Allowable Cw
0.8812
4.7
0.1868 .
86
1.14
5.00 pg/1
5.69 µg/1
0.08 pg/1
Parameter =
Standard =
Silver
0.06
Date n < Actual Data BDL=1/2DL
Oct-01 1 < 5.0 2.5
Oct-01 2 < 2.0 1.0
Oct-01 3 < 5.0 2.5
Oct-01 4 < 5.0 2.5
Oct-01 5 < 5.0 2.5
Oct-01 6 < 5.0 2.5
Sep-01 7 < 5.0 2.5
Sep-01 8 < 5.0 2.5
Sep-01 9 < 5.0 2.5
Sep-01 10 < 5.0 2.5
Sep-01 11 < 5.0 2.5
Sep-01 12 < 5.0 2.5
Jul-01 13 < 5.0 2.5
Jul-01 14 < 5.0 2.5
Jul-01 15 < 5.0 2.5
Jul-01 16 < 5.0 2.5
Jul-01 17 < 5.0 2.5
Jun-01 18 < 5.0 2.5
Jun-01 19 < 5.0 2.5
Jun-01 20 < 5.0 2.5
Jun-01 21 < 5.0 2.5
May-01 22 < 5.0 2.5
May-01 23 < 5.0 2.5
May-01 24 < 5.0 2.5
May-01 25 < 5.0 2.5
May-01 26 < 5.0 2.5
Apr-01 27 < 5.0 2.5
Apr-01 28 < 5.0 2.5
Apr-01 29 < 5.0 2.5
Apr-01 30 < 5.0 2.5
Mar-01 31 < 5.0 2.5
Mar-01 32 < 5.0 2.5
Mar-01 33 < 5.0 2.5
Mar-01 34 < 5.0 2.5
Feb-01 35 < 5.0 2.5
Feb-01 36 < 5.0 2.5
Feb-01 37 < 5.0 2.5
Feb-01 38 < 5.0 2.5
Feb-01 39 < 5.0 2.5
Feb-01 40 < 5.0 2.5
Jan-01 41 < 5.0 2.5
Jan-01 42 < 5.0 2.5
Jan-01 43 < 5.0 2.5
Jan-01 44 < 5.0 2.5
Dec-00 45 < 5.0 2.5
Dec-00 46 < 5.0 2.5
Dec-00 47 < 2.0 1.0
Dec-00 48 < 2.0 1.0
Nov-00 49 < 5.0 2.5
Nov-00 50 < 5.0 2.5
Nov-00 51 < 5.0 2.5
Nov-00 52 < 5.0 2.5
Nov-00 53 < 5.0 2.5
Oct-00 54 < 2.0 1.0
Oct-00 55 < 5.0 2.5
Oct-00 56 < 5.0 2.5
Oct-00 57 < 2.0 1.0
µlb

Sep-00 58 < 5.0 2.5
Sep-00 59 < 5.0 2.5
Sep-00 60 < 2.0 1.0
Sep-00 61 < 2.0 1.0
Aug-00 62 < 5.0 2.5
Aug-00 63 < 5.0 2.5
Aug-00 64 < 5.0 2.5
Aug-00 65 < 5.0 2.5
Aug-00 66 < 5.0 2.5
Aug-00 67 < 5.0 2.5
Jul-00 68 < 5.0 2.5
Jul-00 69 < 5.0 2.5
Ju1-00 70 < 5.0 2.5
Jul-00 71 < 5.0 2.5
Jul-00 72 < 5.0 2.5
Jun-00 73 < 5.0 2.5
Jun-00 74 < 5.0 2.5
Jun-00 75 < 5.0 2.5
Jun-00 76 < 5.0 2.5
Jun-00 77 < 5.0 2.5
May-00 78 < 5.0 2.5
May-00 79 < 5.0 2.5
May-00 80 < 5.0 2.5
May-00 81 < 5.0 2.5
May-00 82 < 5.0 2.5
Apr-00 83 < 5.0 2.5
Apr-00 84 < 5.0 2.5
Apr-00 85 < 5.0 2.5
Mar-00 86 < 2.0 1.0

Facility Name =
NPDCS # _
Q►r (MGD) =
7Q10s (cfs)=
IWC(%) =
CMUD - Irwin Creek
NC0024945
15
4.9
82.59
FINAL RESULTS
Nickel
Max. Pred Cw
AIlowahle Cw
317.7
106.5
RESULTS
Std Dev.
Mean
C.V.
Number
of data points
It?ult Factor =
Max. Value
Max. Pred Cw
Allowable Cw
13.6346
7.8
1.7501
43
3.49
91.0 µg/1
317.7 µg/1
106.5 µg/I
Note: Only one year of data analyized, since RP exist no need to
review additional data.
Parameter =
Standard =
Nickel
88.0
Date n < Actual Data BDL=1/2DL
Oct-01 1 4.3 4.3
Oct-01 2 3.0 3.0
Oct-01 3 3.2 3.2
Oct-01 4 4.1 4.1
Oct-01 5 3.6 3.6
Oct-01 6 4.0 4.0
Sep-01 7 4.7 4.7
Sep-01 8 5.2 5.2
Sep-01 9 5.6 5.6
Sep-01 10 5.6 5.6
Sep-01 11 4.5 4.5
Sep-01 12 3.6 3.6
Jul-01 13 6.1 6.1
JuI-01 14 5.4 5.4
Jul-01 15 4.6 4.6
Jul-01 16 4.8 4.8
Ju1-01 17 4.4 4.4
Jun-0I 18 4.7 4.7
Jun-01 19 5.3 5.3
Jun-01 20 7.1 7.1
Jun-01 21 4.3 4.3
May-01 22 5.7 5.7
May-0 1 23 6.7 6.7
May-01 24 6.7 6.7
May-01 25 5.1 5.1
May-01 26 5.2 5.2
Apr-01 27 4.8 4.8
Apr-01 28 11.0 11.0
Apr-01 29 91.0 91.0
Apr-01 30 14.0 14.0
Mar-01 31 3.8 3.8
µg/1

Mar-O 1 32 3.2 3.2
Mar-01 33 4.1 4.1
Mar-01 34 6.4 6.4
Feb-01 35 7.8 7.8
Feb-01 36 3.9 3.9
Feb-01 37 4.2 4.2
Feb-01 38 3.9 3.9
Feb-01 39 3.1 3.1
Feb-01 40 29.0 29.0
Jan-01 41 6.5 6.5
Jan-01 42 6.2 6.2
Jan-01 43 4.6 4.6

Cu & Zn
Subject: Cu & Zn
From: Mark McIntire <[e-mail]>
Date: Fri, 28 May 2004 13:55:53 -0400
To: [e-mail]
CC: Jackie Nowell <[e-mail]>
Jackie,
I'm sorry it's taken me a bit longer than expected to get in touch
with you about Sugar and Irwin Creek WWTPs. Jackie Nowell and I
wanted to make sure that what we were proposing made sense. As you
know, South Carolina has asked us to limit copper and zinc at both
facilities. Furthermore, as it's South Carolina waters we're most
concerned about, it's South Carolina's methodology we've used. When
Michael Myers originally developed these permits, he used the
lst-percentile of the long-term hardness data. Since then, we've
learned that he should have used the 10th-percentile. As such, we
have recalculated the limits accordingly (see the attached pdf
file) .
Regarding the hardness data, we cannot agree that values collected
during or shortly after rain events should be removed from the data
set. To do so would yield a result that is not representative of the
environment. Furthermore, these facilities discharge continuously.
If they weren't discharging during wet weather events the situation
might be different. We are confident that the long periods of record
(17 and 11-years for Irwin and Sugar respectively) dampen any peaks
and/or valleys that may exist in the data.
Regarding the application of IWC to effluent limitation
calculations, it depends on the type of lithit being developed. For
chronic limits (monthly average or weekly average limits), we do
account for dilution because over the period of concern, complete
mixing will likely have occured. For acute limits (daily maximums),
we are protecting for end -of -pipe impacts during a short-term
exposure period. During that period, complete mixing will not have
occured, thus we do not account for dilution in establishing acute
limits. Finally, where the acute limit is more stringent than the
chronic limit, we exclude the chronic limit from the permit for
obvious mathematical reasons.
It goes without saying that we still propose to give CMU the
originally proposed period of time to develop site -specific criteria
if they so choose. That being said, we have reached the point where
we must issue these permits. Please review the document I've
attached. It should give you a clear understanding as to how the
effluent limitations have been calculated. I would be happy to
discuss this with you anytime next week.
Regards,
Mark
1 of 1 6/1/2004 10:33 AM

Effluent Limitations Summary for Copper and Zinc
Division of Water Quality
May 29, 2004
Irwin Creek
IWC = 83.2%
South Carolina Water Quality standards offer the following equations for recalculation of the
chronic and acute criteria using site -specific hardness data:
CMC = e{ma'In (hardness )-+-ba }
CCC = e { me •ln (hardness }+-bc
Where the CMC is the acute criterion and the CCC is the chronic criterion. Using these
equations and the constants below, we can calculate site -specific CMCs and CCCs for copper
and zinc using ambient hardness data. The ambient hardness data in this case is the 10th
percentile of a 17-year period of record - 58 mg/L.
Copper
Zinc
ma
0.9422
0.8473
ba
-1.7
0.884
m
0.8545
0.8473
bc
-1.702
0.884
CMC
8.4 µg/L
75.5 µg/L
CCC
5.9 µg/L
90.7 µg/L
Daily Maximum Limitation
8.4 ,ug/L
75.5 ,ug/L
Weekly Average Limitation'
7.0 rig/L
No Weekly Average
Limitation2
Notes:
1 The weekly average is intended to protect against chronic (longer -term) impacts. As such,
it is expected that over the duration of concern complete mixing will have occurred. Thus,
the weekly average limit (WAL) includes an accounting for dilution (WAL =
CCC/(IWC/ 100)).
2 For zinc, because the daily maximum is more stringent than the weekly average, no
weekly average is given. Compliance with the daily maximum will always yield compliance
with the weekly average.
CMU — Cu & Zn WLA
NC Division of Water Quality — 5/29/2004

Cu & Zn WLA — Charlotte Mecklenburg Utilities
Sugar Creek
IWC = 90.9%
South Carolina Water Quality standards offer the following equations for recalculation of the
chronic and acute criteria using site -specific hardness data:
CMC = e { ma 'In (hardness )-Fba }
CCC = e { m� • In (hardness)+bc }
Where the CMC is the acute criterion and the CCC is the chronic criterion. Using these
equations and the constants below, we can calculate site -specific CMCs and CCCs for copper
and zinc using ambient hardness data. In accordance with South Carolina permitting, the
ambient hardness data in this case is the 10th percentile of an 11-year period of record - 51.6
mg/L.
Copper
Zinc
ma
_
0.9422
I 0.8473
ba
-1.7
0.884
mc
0.8545
0.8473
b
-1.702
0.884
CMC
7.5 µg/L
68.4 µg/L
CCC
5.3 µg/L
75.2 µg/L
Daily Maximum Limitation
7.5 ug/L
68.4 pg/L
Weekly Average Limitation'
5.8 mg/L
No Weekly Av Zrage
Limitation
Notes:
1 The weekly average is intended to protect against chronic (longer -term) impacts. As such,
it is expected that over the duration of concern complete mixing will have occurred. Thus,
the weekly average limit (WAL) includes an accounting for dilution (WAL =
CCC/(IWC/100)).
2 For zinc, because the daily maximum is more stringent than the weekly average, no
weekly average is given. Compliance with the daily maximum will always yield compliance
with the weekly average.

Charlotte Mecklenburg Utilities- Irwin Creek WWTP
Calculations of copper, zinc and silver effluent limits based on South Carolina water
quality standards
1) Copper limits
SC standard/criteria for copper: CMC = 3.8 ug/1 ; CCC = 2.9 ug/1,
There has been a revision on hardness data used in calculating the limits. After additional
consultation with SCDHEC, it was determined to use the 10`1' percentile of hardness data, rather
than the 1" percentile data value. The new hardness value used will be 58 mg/1 for Irwin Creek
WWTP, based on ambient data from Sugar Creek @ NC 51 at Pineville.
Used the following equation to develop Cu limit
Acute = CMC= e {ma [ln (hardness)] + ba }
Chronic = CCC= e {mc [ln (hardness)] + bc }
ma , ba, mc, and bc are " parameters for calculation freshwater dissolved metals criteria
that are hardness dependent . Reference: SCDEC Water Classifications and Standards.
For Copper, the parameters are as follows:
ma = 0.9422
ba = -1.700
mc = 0.8545
bc = -1.702
The CMC (acute) total copper limit was estimated to be: e (0.9422(1n 58)+ (- 1.7) = 8.38 ug/1
The CMC (acute) dissolved copper limit is estimated to be:
8.38 * CMC conversion factor =
8.38 ug/1* 0.96 = 8.04 ug/1
The CCC (chronic) total copper limit was estimated to be: e (0.8545(ln 58)+(-1.702) = 5.86 ug/1,
Then using the IWC = 83.2%; 5.86 ug/1/0.832= 7.04 ug/1—total Cu w/dilution
The CCC (chronic) dissolved copper limit is estimated to be:
7.04 ug/1* CCC conversion factor --
7.04 ug/1* 0.96 = 6.76 ug/1

•
Charlotte Mecklenburg Utilities- Irwin Creek WWTP
Calculations of copper, zinc and silver effluent limits based on South Carolina water
quality standards
2) Zinc limits
SC standard/criteria CMC = 37 ug/1; CCC = 37 ug/1,
DWQ used the following equation to develop Zn limit for Irwin Creek WWTP, using
hardness of 36 mg/1 from ambient data.
Acute = CMC= e { ma [ln (hardness)] + ba }
Chronic = CCC= e {mc [ln (hardness)] + bc }
ma , ba, mc, and bc are " parameters for calculation freshwater dissolved metals criteria
that are hardness dependent . Reference: SCDEC Water Classifications and Standards.
For Zinc, the parameters are as follows:
ma = 0.8473
ba = 0.884
mc = 0.8473
bc = 0.884
The CMC (acute) total zinc limit was estimated to be: e (0.8473(ln 58)+ 0.884 = 75.5 ug/1
The CMC (acute) dissolved zinc limit is estimated to be:
75.5 ug/1* CMC conversion factor =
75.5 ug/1* 0.978 = 73.9 ug/1
The CCC (chronic) zinc limit was estimated to be: e (0.8473(ln 58)+ 0.884 =1

i
Charlotte Mecklenburg Utilities- Irwin Creek WWTP
Calculations of copper, zinc and silver effluent limits based on South Carolina water
quality standards
3) Silver limits
A review of the silver effluent data showed that all data was below detection level, therefore no
reasonable potential analysis was required. There was no potential to exceed the allowable
concentration. Therefore, the proposed silver limit will be removed. See attached table with
silver data.
Jacquelyn Nowell
NPDES Unit
5/10/2004

Re: [Fwd: Hardness Data for metal limits]
Subject: Re: [Fwd: Hardness Data for metal limits]
From: "Michael Montebello" <[e-mail]>
Date: Fri, 07 May 2004 07:06:19 -0400
To: <[e-mail]>
CC: "Jeff DeBessonet" <[e-mail]>, "Michael Montebello" <[e-mail]>
Ms. Nowell,
I will assume the data has been collected seasonally over this period of record.
If you are going to ONLY use the downstream ambient data in the calculation (and not a mixed hardness calculation of
effluent and upstream(unimpacted water)then we would use the loth percentile of the data set.
The sampling stations must be far enough downstream from the wastewater treatment plant to eliminate any question
over whether the hardness data collected is either in an effluent plume (and not representative of the "true" stream
data) or so close to the discharge point to be a measure of effluent hardness and not stabilized stream hardness.
If the instream data would indicate a unusally high hardness values, I would verify that the hardness noted continues
to be seen at the next station downstream.
Thanks
Mike Montebello
Jackie Nowell <[e-mail]> 05/06/04 15:46 PM »>
Thanks for the information, Mike, it was helpful. I still need some
clarification and hope you can provide. In calculating the metals
limits for the CMU plants, we used hardness data from two DWQ ambient
stations, one which was downstream of the Irwin Creek plant and the
other downstream of the Sugar Creek plant. The data was for the period
from 1983 throught 2000 with over 115 values for each station. What
percentile of this type of hardness data should we use in the
calculation of the metals limits?.
Michael Montebello wrote:
Ms. Nowell:
Attached is an excerpt from our NPDES permit Rationale to describe the
derivation of the numbers used in the metals limitations. The
formula's used are consistent with the EPA published documents.
The hardness calculation is a mixed vlue (flow proportioned) based on
the upstream hardness and the effluent hardness. The assumption
without stream data is that the hardness is 25 mg/1. The same
assumption is made for the effluent data. If the permittee has
effluent hardness data we use the 10th percentile of the data in the
calculation. We would typically expect the background stream hardness
(unimpacted by wastewater dischargers) to be less than 25 mg/1. If a
POTW proposes to use an effluent hardness value in the formula in
excess of 50 to 60 mg/1 (without a substantial amount of actual
effluent data) we would include a permit limitation specifying a
minimum hardness value. In limited locations in SC (primarily in
Coastal Regions) , if the main source of the water supply is
from groundwater, the expected effluent hardness value may be somewhat
higher.
Thank you,
Mike Montebello
For the parameters listed in Table A below, Regulation R.61-68 Section
E.12 provides for the use of the EPA Office of Water Policy and
"Technical Guidance on Interpretation and Implementation of Aquatic
Life Metals Criteria", October 1, 1993. A subsequent revision
published in the Federal Register (60 FR 22229) on May 4, 1995 updated
the data in the original report. See R.61-68 Attachment 1 "Conversion
Factors for Dissolved Metals" and Attachment 2 "Parameter for
Calculating Freshwater Dissolved Metals Criteria that are
Hardness -Dependent". The following equations and constants will be
used to calculate aquatic life metals limits based on the Federal
Register data. The water quality standard for these metals (CCC or
CMC) will also be adjusted using this approach in accordance with
Regulation 61-68.E.12.d(3) for evaluation of ambient water quality.
TSSe Effluent Total Suspended Solids (TSS) concentration in mg/1 as
determined from atual long term average data or proposed monthly
average permit limits.
TSSb Background or in -stream Total Suspended Solids (TSS)
concentration. The background TSS is assumed to be 1 mg/1 in the
absence of actual stream data based on the 5th percentile of ambient
TSS data on South Carolina streams from 1993-2000.
TSSavg Average in -stream (mixed) TSS concentration
1 of 5 7/13/2004 3:54 PM

Re: [bFwd,: Hardness Data for mctal limits]
Subject: Re: [Fwd: Hardness Data for metal limits]
From: "Michael Montebello" <[e-mail]>
Date: Wed, 05 May 2004 15:19:35 -0400
To: <[e-mail]>
CC: "Jeff DeBessonet" <[e-mail]>
Ms. Nowell:
Attached is an excerpt from our NPDES permit Rationale to
describe the derivation of the numbers used in the metals
limitations. The formula's used are consistent with the EPA
published documents.
The hardness calculation is a mixed value (flow
proportioned) based on the upstream hardness and the
effluent hardness. The assumption without stream data is
that the hardness is 25 mg/1. The same assumption is made
for the effluent data. If the permittee has effluent hardness
data we use the loth percentile of the data in the
calculation. We would typically expect the background
stream hardness (unimpacted by wastewater dischargers) to
be less than 25 mg/l. If a POTW proposes to use an effluent
hardness value in the formula in excess of 50 to 60 mg/1
(without a substantial amount of actual effluent data) we
would include a permit limitation specifying a minimum
hardness value. In limited locations in SC (primarily in
Coastal Regions) , if the main source of the water supply is
from groundwater, the expected effluent hardness value
may be somewhat higher.
Thank you,
Mike Montebello
For the parameters listed in Table A below, Regulation R.61-68
Section E.12 provides for the use of the EPA Office of
Water Policy and "Technical Guidance on Interpretation
and Implementation of Aquatic Life Metals Criteria",
October 1, 1993. A subsequent revision published in the
Federal Register (60 FR 22229) on May 4, 1995 updated
the data in the original report. See R.61-68 Attachment 1
"Conversion Factors for Dissolved Metals" and Attachment
2 "Parameter for Calculating Freshwater Dissolved Metals
Criteria that are Hardness -Dependent". The following
equ a s anrl_ constan s will be used to calculate aquatic
life metals limits based on the Federal Register data. The
1 of 4 5/6/2004 9:39 AM

Re: [Fwq: Hardness Data for metal limits]
water quality standard for these metals (CCC or CMC) will
also be adjusted using this approach in accordance with
Regulation 61-68.E.12.d(3) for evaluation of ambient water
quality.
TSS, Effluent Total Suspended Solids (TSS) concentration
in mg/1 as determined from actual long term
average data or proposed monthly average
permit limits.
TSSb Background or in -stream Total Suspended Solids
(TSS) concentration. The background TSS is
assumed to be 1 mg/1 in the absence of actual
stream data based on the 5th percentile of
ambient TSS data on South Carolina streams
from 1993-2000.
TSSavg Average in -stream (mixed) TSS concentration
CF Conversion factor considered most relevant in fresh
water for aquatic life as defined by EPA in
dissolved metals documents for each listed
metal
H Hardness in mg/1 of CaCO3. Per R.61-68.E.12.a(3), the
CMC and CCC are based on a hardness of 25
mg/1 if the ambient hardness is less than 25
mg/1. Concentrations of hardness less than 400
mg/1 may be based on the actual mixed stream
hardness if it is greater than 25 mg/1 and less
than 400 mg/1 and 400 mg/1 if the ambient
hardness is greater than 400 mg/l. The
background hardness is assumed to be 25 mg/1
in the absence of actual stream data. Mixed
stream hardness may be determined using
effluent hardness and actual stream hardness.
The effluent hardness is assumed to be 25 mg/1
in the absence of actual effluent data or based
on the 10th percentile of actual effluent
hardness data.
Kpo Metal -specific equilibrium constant
a Metal -specific constant
Kp Linear partition coefficient
Cd Dissolved phase metal concentration
Ct Total metal concentration
S a constant to represent the CCC or CMC
2 of 4 5/6/2004 9:39 AM

Re: [Fw4: Hardness Data for metal limits]
The following table lists the values for the constants, the
CCC and CMC and the recommended values of the
conversion factor (CF)
Table A:
Parameter
kpo
a
CMC
CFCMC
CCC
CFccc
(11g/1)
(nil)
Arsenic
0.48 x
106
-0.7286
340
100
150
100
Cadmium
4.00 x
106
-1.1307
0.95*
100*
0.83*
96.7*
Chromium+3
3.36 x
106
-0.9304
580*
31.6
68*
86
Chromium+6
3.36 x
106
-0.9304
16
98.2
11
96.2
Copper
1.04 x
106
-0.7436
3.8*
96
2.9*
96
Lead
0.31 x
106
-0.1856
14*
99.3*
0.54*
99.3*
Mercury
2.91 x
106
-1.1356
1.6
85
0.091
85
Nickel
0.49 x
106
-0.5719
150*
99.8
16*
99.7
Zinc
1.25 x
106
-0.7038
37*
97.8
37*
98.6
* The equations for calculating the CCC, CMC, and conversion factors
are given in the Appendix to Regulation 61-68 and Attachments land 2
for each parameter. The values given for the CMC and CCC and CF in
the table are based on 25 milligrams/liter (mg/1) hardness (as expressed
as CaCO3).
Michael Montebello, Manager
Domestic Wastewater Permitting Section
Phone [phone]
Fax [phone]
[e-mail]
3 of 4 5/6/2004 9:39 AM

Re: [Fw4: Hardness Data for rngtal limits]
»> Jackie Nowell <[e-mail]> 05/05/04 02:23PM »>
Original Message
Subject:Hardness Data for metal limits
Date:Wed, 05 May 2004 11:45:39 -0400
From:Jackie Nowell <[e-mail]>
To:Jeff DeBessonet <[e-mail]>, Michael Montebello
<[e-mail]>
Hello Jeff and Mike,
Hope that all is well. We need your help with information on how
SC uses hardness data when developing metals limits. Could you forwa:
us some guidance on what percentile of hardness data is used ? Also
you use ambient hardness data and effluent hardness data in your
calculations? Any sample calculations on how a metals limit would be
derived would be appreciated. We are verifying that our limits
development for the CMU facilities is consistent with SC methods.
Thank you
Jackie Nowell
4 of 4 5/6/2004 9:39 AM

•
cax
CHARLOTTEsM
April 29, 2004
David Goodrich
Jackie Nowell
NCDWQ — NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
MAY 1 0 2004
Subject: Proposed Permit Limits, Irwin Creek WWTP NPDES Permit#NC0024945 and Sugar Creek
WWTP NPDES Permit #NC002495
Dear Dave and Jackie:
Based upon your conversation with Ms. Dawn Padgett, we are sending you some background
information that Charlotte Mecklenburg Utilities, Environmental Management Division has put together
pertaining to the proposed limits for copper and zinc at the Sugar Creek WWTP (NPDES Permit
#NC0024937) and Irwin Creek WWTP (NPDES Permit #NC0024945). We also have some questions
about the original calculations.
Attached is a spreadsheet that shows the hardness data that we have received from NCDWQ. We
have added the stream flows and rain fall information to this spreadsheet, named "hardness data".
The stream flow data is from the USGS stream gauge located at site LSC3, below Sugar Creek WWTP
and the gauge located at site SC4, below Irwin Creek WWTP. We received the rainfall data from the
Mecklenburg County Storm Water Division. At this time, we only used the State hardness data that we
could get both rainfall and creek flow information at the site. At the SC4 site, data from 1/4/1995 to
present has been used. At the LSC3 site, data from 6/17/1997 to present has been used. All of the
hardness samples collected by the State are included with the Stream flows and rainfall information.
The second spreadsheet that is attached is named "ambient — based on rainfall". Clarification of the
definition for what "ambient" conditions was requested from both Mecklenburg County and City of
Charlotte Storm Water Divisions. They stated that a rainstorm condition in the stream was considered
any time that a rainfall equaled or exceeded a rain event of 0.10" of rain in the previous 72 hours or that
the creeks were elevated above 0.5'. We asked where the criteria was originated from and they
indicated that it was based on Federal Guidance documents for Storm Water Programs.
In addition to providing you the enclosed data, we will soon be providing you with calculations of
proposed limits for copper and zinc. We would then like to meet with you to discuss the proposed
permitting approach.
In providing such information, we request NCDWQ feedback on its approach for applying the IWC to
Environmental Management Division 4000 Westmont Dr. Charlotte, NC 28217
Phone: [phone] Charlotte -Mecklenburg Utilities

•
CHARLOTTEsm
the acute and chronic limits. The IWC was not applied to the acute limits when the State did the
original calculations that were included with the Permit fact sheet. Please let us know if the IWC is not
supposed to be applied to acute limits, and if this should not be applied why. We appreciate NCDWQ
taking whatever steps are necessary to ensure that we be provided the requisite information identifying
how the proposed limits were calculated.
Please let me, or Dawn Padgett know if you have any questions about the spreadsheets or about this
cover letter. We look forward to discussing all of this with you, in person, as soon as possible.
Thank you for your consideration,
Sincerely,
,J'acqu line A. Jarrell-
Environmental Management Division Supt.
Charlotte Mecklenburg Utilities
C: D. Padgett
Environmental Management Division 4000 Westmont Dr. Charlotte, NC 28217
Phone: [phone] Charlotte -Mecklenburg Utilities

•
� M G s
erN) 2AINrA Lam.
STATION ;DATE 1-IARDNESS TOTAU stream flok{ Rain data
Sugar Creek at NC51 in Pine (MG/L AS CACO3)
1
C9050000!
1/4/1995 11:50! 75 45
no rain in the past 72 hours
C9050000
2/6/1995 10:15 ! 73 47
no rain in the past 72 hours
C9050000
4/17/1995 12:40; 82
36
no rain in the past 72 hours
C9050000
9/7/1995 9:551 88
67
no rain in the past 72 hours
C9050000
10/3/1995 9:401 74
44
no rain in the past 72 hours
C9050000
2/6/1996 12:20' 71
141
no rain in the past 72 hours
C9050000
3/5/1996 10:35
96
43
no rain in the past 72 hours
C9050000
6/4/1996 11:20
80
46
no rain in the past 72 hours
C9050000
12/17/1996 10:10
86
85
0.08" of rain in the past 72 hours
C9050000
3/17/1997 11:40
89
60
0.01" of rain in the past 72 hours
C9050000
5/14/1997 10:35 87
44 no rain in the past 72 hours
C9050000
7/21 /199710:55 , 65
51 0.07" of rain in the past 72 hours
C9050000
9/18/1997 10:00
100
25'0.02" of rain in the past 72 hours
C9050000
12/8/1997 11:40
72
42
no rain in the past 72 hours
C9050000
1/6/1998 14:15
85
163
0.018" of rain in the past 72 hours
C9050000
3/5/1998 10:30
100
65
no rain in the past 72 hours
C9050000
5/5/1998 13:55
58
52
0.036" of rain in the past 72 hours
C9050000
7/15/1998 10:10
84
33
no rain in the past 72 hours
C9050000
8/4/1998 11:40 70
28
no rain in the past 72 hours
C9050000
9/2/1998 11:30 71
36
no rain in the past 72 hours
C9050000
12/2/1998 11:10, 76
27
no rain in the past 72 hours
C9050000
3/3/1999 0:00 120
53
0.0075" of rain in the past 72 hour:
C9050000
4/5/1999 0:00 79.2
42
no rain in the past 72 hours
C9050000
5/4/1999 0:00
84.84
46
no rain in the past 72 hours
C9050000
6/3/1999 0:00
92
30
no rain in the past 72 hours
C9050000
8/5/1999 0:00
66
29
no rain in the past 72 hours
C9050000
10/7/1999 0:00
72.72
27
0.059" of rain in the past 72 hours
C9050000
12/1/1999 0:00
82.472
35
no rain in the past 72 hours
C9050000' 1 /3/200011:10
85.8
35
no rain in the past 72 hours
C9050000 2/1/2000 11:00
64.8
120
0.04" of rain in the past 72 hours
C9050000
5/8/2000 11:00
69
31
no rain in the past 72 hours
C9050000
8/17/2000 11:30
85
24
no rain in the past 72 hours
SC4
12/17/2002
86
54
no rain in the past 72 hours
SC4
04/14/03
74
107
0.04" of rain in the previous 72 hot,
SC4
08/18/03
85
60
0.04" of rain in the previous 72 hot,
SC4
09/15/03
91
36
no rain in the past 72 hours
SC4 10/1/03
74
33
no rain in the past 72 hours
SC4 11/10/03
86
33
0.05" of rain in the previous 72 hot,
SC4 2/18/04
80 49
no rain in the past 72 hours
SC4 2/23/04
102 39
no rain in the past 72 hours
SC4 3/8/04
94 42
no rain in the past 72 hours
SC4 3/29/04
94.8 37
no rain in the past 72 hours
Count 42
average
82.15790476
Mean
83
Standard Deviatiorl
12.01555857
99th percentile 46.95332428

M n 1 t)J1:15LI)
'.� z At i /Q /4 L c,
STATION 1 DATE 0 TOTAL (MG/L i Rain data
streamflow (cfs)
Little Sugar Creek at NC521 in Pineville
C9210000
_ 7/21/1997 12:55
59
0.03" of rain in i
38
C9210000-
9/18/1997 10:50
64
no rain in the pc
30
C9210000
11/20/1997 10:45
100
0.01" of rain in 1
40
C9210000
12/8/1997 12:30
64
no rain in the p
44
C9210000
3/5/199811:10
100
no rain in the p<
53
C9210000
7/15/1998 11:00
96
no rain in the p
30
C9210000
8/4/1998 13:30
62
no rain in the r
36
C9210000
9/2/1998 13:20
61
no rain in the p
31
C9210000
12/2/1998 13:20
69
no rain in the p
27
C9210000
3/3/1999 0:00
100
0.02" of rain in 1
68
C9210000
4/5/1999 0:00
85.14
0.087" of rain ir
38
C9210000
5/4/1999 0:00
74.74
no rain in the pi
36
C9210000
6/3/1999 0:00
64
no rain in the pi
30
C9210000
8/5/1999 0:00
50
I no rain in the pi 30
C9210000
10/7/1999 0:00
50
0.097" of rain ir
31
C9210000
12/1/1999 0:00
61.854
no rain in the pi
34
C9210000
1/3/2000 12:35
72.6
no rain in the pi
32
C9210000
2/1/2000 13:05
75.6
0.04" of rain in 1
95
C9210000
5/8/2000 12:45
69
no rain in the pi
38
C9210000
8/17/2000 15:00
54
no rain in the pi
31
LSC3
12/17/2002
73
no rain in the pi
45
LSC3
01/22/03
76
0.06" of rain in 1
46
LSC3
04/14/03
68
0.05" of rain in 1
76
LSC3
08/18/03
61
0.01" of rain in i
68
LSC3
09/15/03
66
no rain in the p
39
LSC3
10/01/00
64
no rain in the p5
381
LSC3
11/10/03
67
0.08" of rain in i
32
LSC3 • 2/23/04
72
no rain in the pi
38
LSC3
3/8/04
86
no rain in the pi
35
LSC3
3/22/04
74
no rain in the p
40
LSC3
3/29/04
69.2
no rain in the p
38
Count
31
average
71.23012903
Mean
69
Standard Deviation
13.64416209
99th percentile
28.06751373

STATION DATE
DEPTH
HARDNEE
stream floe
Rain data
Sugar Creek at NC51 in Pineville
C9050000 2/14/198311:20
0
56
C9050000
C9050000
C9050000
C9050000
5/26/198311:00
0
83
8/31/198311:10
0
66
11/17/1983 10:55
0
86
5/22/198411:00
0
75
C9050000 8/28/1984 11:45
0
88
C9050000 11/27/1984 10:45
0
86
C9050000 1/30/1985 10:40
0
80
C9050000 2/25/198511:55
0
90
C9050000
C9050000
3/28/198511:35
0
82
4/23/198511:50
0
79
C9050000
5/22/198511:50
0
80
C9050000
6/25/1985 11:55
0
50
C9050000
7/23/1985 11:40
0.32808
64
C9050000
8/21/1985 12:00
0.32808
86
C9050000
9/19/198511:30
0.32808
82
C9050000
10/21 /1985 11:30
0.32808
87
C9050000
11 /20/1985 11:00
0.32808
84
C9050000
12/18/1985 10:45
0.32808
87
C9050000
1 /29/1986 10:40
0.32808
110
C9050000
2/19/1986 11:20
0.32808
1.20
96
79
C9050000
3/20/198610:30
0.32808
C9050000
4/15/1986 11:00
0.32808
C9050000
5/21/1986 13:10
0.32808
51
C9050000
6/12/1986 10:45
0.32808
75
C9050000
7/21/198611:25
0.32808
73
C9050000
8/13/1986 12:00
0.32808
51
C9050000
9/16/1986 12:35
0.32808
68
77
72
951
C9050000
10/16/1986 15:40
0.32808
C9050000 11 /13/1986 15:20
0.32808
C9050000 2/4/1987 11:55
0.32808
C9050000 5/6/198711:00
0.32808 75
C9050000 8/5/1987 12:20
0.32808 67
C9050000 11 /5/1987 11:05
0.32808 82
C9050000 2/3/198811:15
0.32808 58
C9050000 5/4/1988 10:46
0.32808
89
C9050000 8/9/1988 10:20
0.32808
77
C9050000
C9050000
11 /8/1988 11:30
0.32808
73
2/9/1989 10:15
0.32808
586
C9050000
C9050000
5/3/1989 11:45
0.32808
63
8/2/1989 12:00
0.49199
75
C9050000 11/7/1989 10:10
0.32808
91
C9050000 2/8/1990 12:40
0.32808
81
C9050000 5/8/199011:00
0.32808
73
C9050000
C9050000
8/8/1990 12:55
0.32808
66
11 /14/1990 14:55
0.32808
86
C9050000 5/21/1991 18:10
0.32808
80
C9050000
8/20/1991 16:25
0.32808
90,
C9050000
9/18/1991 13:30
0.32808
72
C9050000
10/15/1991 13:50
0.32808
82

.3
C9050000
11/25/1991 13:55
0.32808
92
C9050000
12/18/1991 14:20
0.32808
100
C9050000
1/16/1992 12:40
0.32808
75
C9050000
2/18/1992 15:25
0.32808
67
C9050000
3/25/1992 13:30
0.32808
72
C9050000
4/29/1992 14:20
0.32808
83
C9050000
5/27/1992 15:30
0.32808
66
C9O50O00
6/24/1992 15:40
0.32808
83
C9050000
7/29/1992 14:15
0.32808
73
C9O50O00
8/26/1992 14:00
0.32808
82
C9O50000
9/29/1992 13:20
0.32808
48
C9O50O00
10/22/1992 14:40
0.32808
100
C9O50000
11 /30/1992 13:00
0.32808
73
C9050000
12/30/199214:45
0.32808
68
C9050000
1 /26/199313:00
0.32808
71
C9050000
2/23/1993 14:45
0.32808
67
C9050000
3/23/1993 14:50
0.32808
76
C9050000
4/22/1993 13:45
0.32808
87
C905O000
5/12/199314:15
0.32808
78
C905O000
6/23/1993 10:15
0.32808
100
C905000O
7/14/1993 14:30
0.32808
63
C9050000
8/5/1993 15:40
0.32808
80
C905000O
9/20/1993 11:15
0.32808
64
C9050000
10/12/1993 14:29
0.32808
56
C9050000
11/3/1993 11:20
0.328081
79
C9050000
2/10/199411:20
0.32808
76
C9050000
3/17/1994 12:20
0.32808
60
C9050000
4/21 /199411:15
0.32808
76
C9050000
5/17/1994 9:35
0.32808
64
C9050000
6/21 /199410:30
0.32808
83
C90500O0
7/18/199411:00
0.32808
56
C9050000
8/17/1994 10:25
0.32808
36
C9050000
9/8/199411:15
0.32808
69
C9050000
10/19/1994 12:25
0.32808
82
40
C9050000
11/15/1994 10:30
0.32808
82
39
C9050000
12/8/1994 10:50
0.32808
83
45
C9050000
1/4/1995 11:50
0.32808
75
45
no rain in the past 72 hours
C9O50000
2/6/1995 10:15
0.32808
73
47
no rain in the past 72 hours
C9050O00
3/7/1995 11:30
0.32808
69
91
0.21" of rain in the past 72 hours;
C9050000
4/17/1995 12:40
0.32808
82
36
no rain in the past 72 hours
C9O50O00
5/10/1995 11:201
0.32808
70
233
1.36" of rain in the past 72 hours'
C9O50000
6/1/1995 10:20
0.32808
75
34
0.685" of rain in the past 72 hours
C9050000
8/3/1995 10:15
0.32808
100
45
0.57" of rain in the past 72 hours
C9050000
9/7/1995 9:55
0.32808
88
67
no rain in the past 72 hours
C9050000
10/3/1995 9:40
0.32808
74
44
no rain in the past 72 hours
C905O00O
11/2/1995 10:50
0.32808
62
686
0.81" of rain in the past 72-hours]
C905O000
12/7/1995 11:30
0.32808
100
150
0.31" of rain in the past 72 hours
C905000O
1/4/1996 10:50
0.32808
70
45
0.33" of rain in the past 72 hours
C9050000
2/6/1996 12:20
0.32808
71
141
no rain in the past 72 hours
C9050000
3/5/1996 10:35
0.32808
96
43 no rain in the past 72 hours
C9050000
4/3/1996 10:40
0.32808
76
91
0.69" of rain in the past 72 hours
C90500001 5/1/1996 12:20 0.32808
72
181
1.61" of rain in the past 72 hours

C90500001 6/4/1996 11:20 0.32808
80
46
no rain in the past 72 hours
C90500001 7/2/1996 10:301 0.32808
48
70
0.1" of rain in the past 72 hours
C90500001 8/6/1996 11:00 0.32808
78
42
0.64" of rain in the past 72 hours
C90500001 9/4/1996 11:10 0.32808
54
331
0.22" of rain in the past 72 hours
C90500001 10/24/1996 10:45 0.32808
84
30
0.1" of rain in the past 72 hours
C9050000' 11/19/1996 10:00
0.32808
56
119
0.42" of rain in the past 72 hours,
C9050000 12/17/1996 10:10
0.32808
861
85
0.08" of rain in the past 72 hours
C90500001 1/29/1997 11:50
0.32808
78
64
0.14" of rain in the past 72 hours
C9050000 2/11/1997 10:50
0.32808
73
88
0.1" of rain in the past 72 hours
C9050000 3/17/1997 11:40
0.32808
89
60
0.01" of rain in the past 72 hours
C9050000
4/8/1997 12:30
0.32808
78
46
0.25" of rain in the past 72 hours,
C9050000
5/14/1997 10:35
0.32808
87
44
no rain in the past 72 hours
C9050000 6/12/1997 11:45
0.32808
52
103
0.44" of rain in the past 72 hours
C9050000 7/21/1997 10:55
0.32808
65
51
0.07" of rain in the past 72 hours
C9050000
8/13/1997 10:10'
0.32808
82
28
0.37" of rain in the past 72 hours
C9050000
9/18/1997 10:00 0.32808
100
25
0.02" of rain in the past 72 hours
C9050000
10/28/1997 10:00
0.32808
67
54
1.85" of rain in the past 72 hours
C9050000
11/20/1997 10:05
0.32808
120
24
0.2" of rain in the past 72 hours
C9050000
12/8/1997 11:40
0.32808
72
42
no rain in the past 72 hours
C9050000
1/6/1998 14:15
0.32808
85
163
0.018" of rain in the past 72 hours
C9050000 2/3/1998 10:101
0.32808'
94
336
0.31" of rain in the past 72 hours
1
C9050000
3/5/1998 10:30 , 0.32808
100 65
no rain in the past 72 hours
1
C9050000
4/2/1998 10:501 0.32808
60 84
0.21" of rain in the past 72 hours
C9050000
5/5/1998 13:551 0.32808
58 52
0.036" of rain in the past 72 hours
C9050000 6/10/1998 14:251 0.32808
51 568
0.35" of rain in the past 72 hours
C9050000 7/15/1998 10:10` 0.32808 84 33 no rain in the past 72 hours
C9050000 8/4/199811:401 0.32808
70 28' no rain in the past 72 hours
C9050000 9/2/199811:301 0.32808
71 36' no rain in the past 72 hours
C905000010/1/1998 10:55 0.32808
82 3710.23" of rain in the past 72 hours
C9050000 11/5/1998 9:40, 0.32808
561 37' 0.89" of rain in the past 72 hours
C9050000 12/2/199811:101 0.32808
761 27 no rain in the past 72 hours
C9050000 1/4/1999 11:40
0.32808
70.561 9410.32" of rain in the past 72 hours
C9050000 2/3/1999 10:30
0.32808
71.411 87 0.86" of rain in the past 72 hoursj
C9050000' 3/3/1999 0:00 0.32808 120' 53 0.0075" of rain in the past 72 hours
C9050000 4/5/1999 0:00 0.32808 79.21 42
no rain in the past 72 hours
C90500001 5/4/1999 0:00 0.32808
84.84
46
no rain in the past 72 hours
C9050000 6/3/1999 0:00 0.32808
92
30
no rain in the past 72 hours
C9050000 7/1/1999 0:00
0.32808
73.26
33
0.32" of rain in the past 72 hoursi
C9050000 8/5/1999 0:00
0.32808
66
29
no rain in the past 72 hours
C9050000
9/7/1999 0:00
0.32808
60
34
0.87" of rain in the past 72 hours
C9050000
10/7/1999 0:00
0.32808
72.72
27
0.059" of rain in the past 72 hours
C9050000
11/3/1999 0:00
0.32808
58.824
56
0.44" of rain in the past 72 hours
C9050000
12/1/1999 0:00
0.32808
82.472'
35
no rain in the past 72 hours
C9050000
1/3/2000 11:10
0.32808
85.8
35
no rain in the past 72 hours
C9050000
2/1/2000 11:00'
0.32808
64.8
120
0.04" of rain in the past 72 hours
C9050000
3/1/2000 11:10
0.32808
82.32
38
0.71" of rain in the past 72 hours
C9050000
4/3/2000 12:50
0.32808
74.88
108
0.28" of rain in the past 72 hours
C9050000
5/8/2000 11:00
0.32808
69
31
no rain in the past 72 hours
C9050000
6/8/2000 10:20
0.32808
110
27
1.03" of rain in the past 72 hours
C9050000
7/25/2000 9:40
0.32808
60
41 0.49" of rain in the past 72 hours
C9050000
8/17/2000 11:30
0.32808
85, 24 no rain in the past 72 hours
C9050000
9/20/2000 11:15 0.32808
661 40 1.12" of rain in the past 72 hours

•
C90500001 12/19/2000 10:501 0.328081 631 4010.45" of rain in the past 72 hours'

r IL
STATION 1 DATE 'DEPTH HARDNESstreamflow Rain data
Little Sugar Creek at NC521 in Pineville
C9210000 2/9/198914:05 0.32808 63
C9210000 5/3/198912:30, 0.32808 60
C9210000 8/2/198912:30 0.49199 75
C9210000 11 /7/1989 11:30 0.32808 75
C9210000 2/8/199013:30 0.32808 73
C9210000 5/8/199011:30 0.32808 64
C9210000 8/8/199014:00 0.32808 57
C9210000 11 /14/1990 15:25 0.32808 78
C9210000 5/21/1991 17:15 0.32808 67
C9210000 8/20/1991 14:45 0.32808 70
C9210000 9/18/199114:30; 0.32808 60
C9210000 10/15/1991 14:35 0.32808 57
C9210000 11/25/1991 13:00 0.32808 63'
C9210000 12/18/1991 13:40 0.32808 70
C9210000 1 /16/1992 13:15 0.32808 73
C9210000 2/18/199214:45 0.32808 61
C9210000 3/25/1992 14:10 0.32808 64
C9210000 4/29/199212:45 0.32808 71
C9210000 5/27/1992 15:00 0.32808 66
C9210000 6/24/1992 14:45 0.32808 64
C9210000 7/29/199214:45 0.32808 61
C9210000 8/26/1992 14:50 0.32808 57
C9210000 9/29/1992 14:00 0.32808 46
C9210000 10/22/199214:00 0.32808 78
C9210000 11 /30/1992 13:30 0.32808 71
C92100001 12/30/1992 14:00 0.32808 66
C9210000 1 /26/1993 13:30 0.32808 75
C9210000 2/23/1993 14:00 0.32808 63
C9210000 3/23/199314:15 0.32808 68
C9210000 4/22/1993 14:15 0.32808 85
C9210000 5/12/1993 15:00 0.32808i_ 70
C9210000 6/23/1993 10:55 0.32808' 95
C9210000 7/14/1993 15:00 0.32808 71
C9210000 8/5/1993 15:15 0.32808 56
C9210000 9/20/1993 12:00 0.32808 52
C9210000 10/12/1993 13:49 0.32808 43
C9210000 11 /3/1993 13:25 0.32808 56
C9210000 2/10/199412:45 0.32808 64
C9210000 3/17/199414:10 0.32808 81
C9210000 4/21/1994 13:15 0.32808 68
C9210000 5/17/1994 10:35 0.32808 58
C9210000 6/21/199411:20 0.32808 67
C9210000 7/18/1994 12:30 0.32808 48
C9210000 8/17/1994 11:15 0.32808 36
C9210000 9/8/1994 13:20 0.32808 59
C9210000 10/19/1994 14:15 0.32808 68
C9210000 11/15/1994 11:25 0.32808 64
C9210000 12/8/1994 13:20 0.32808 78
C9210000 1 /4/1995 14:00 0.32808 65
no rain in the past 72 hours
C9210000 2/6/199511:15 0.32808 69
0.09" of rain in the past 72 hours

C9210000
3/7/1995 13:30 0.32808 671 0.21" of rain in the past 72 hours;
C9210000
4/17/1995 14:55 0.32808 70' ; no rain in the past 72 hours
C9210000
5/10/1995 12:10 0.32808 42 j 0.59" of rain in the past 72 hours
C9210000
6/1/1995 11:15 0.328081 57 1 no rain in the past 72 hours
C9210000
8/3/1995 11:00 0.328081 73 ! 0.42" of rain in the past 72 hours
C9210000
9/7/1995 10:45 0.32808 73 no rain in the past 72 hours
C9210000
10/3/1995 10:40
0.32808' 72
no rain in the past 72 hours
C9210000
11/2/1995 11:35
0.32808 36
0.70" of rain in the past 72 hours
C9210000
12/7/1995 12:10
0.32808 68
0.39" of rain in the past 72 hours
C9210000
1/4/1996 11:30
0.32808' 68
0.31" of rain in the past 72 hours
C9210000
2/6/1996 14:OOF
0.32808
73
no rain in the past 72 hours
C9210000
3/5/1996 11:20
+ 0.32808
82, no rain in the past 72 hours
C9210000
4/3/1996 12:00
0.32808
88
0.64" of rain in the past 72 hours
C9210000
5/1/1996 14:15
0.32808
64
1.85" of rain in the past 72 hours
C9210000
6/4/1996 13:30
0.32808
76
0.0018" of rain in the past 72 hours
C9210000
7/2/1996 11:20
0.32808
62
0.087" of rain in the past 72 hours
C9210000'
8/6/1996 11:50
0.32808
58
0.20" of rain in the past 72 hours
C9210000 9/4/1996 11:50
0.32808'
54, 1.08" of rain in the past 72 hours
C9210000
10/24/1996 11:30
0.32808
92
0.007" of rain in the past 72 hours
C9210000
11/19/1996 10:45
0.32808
54
0.43" of rain in the past 72 hours
C9210000
12/17/1996 11:00
0.32808
66
0.093" of rain in the past 72 hours
C9210000
1/29/1997 12:30
0.32808
641
'0.12" of rain in the past 72 hours 1
C9210000
2/11/1997 11:40
0.32808 71
0.12" of rain in the past 72 hours'
C9210000
3/17/1997 12:15
0.32808 82
0.013" of rain in the past 72 hours
C9210000
4/8/1997 13:50 0.32808 74
0.25" of rain in the past 72 hours
C9210000
5/14/1997 11:25 0.32808
711
no rain in the past 72 hours
C9210000
6/12/1997 12:45 0.32808
44
162
0.37" of rain in the past 72 hours;
C9210000
7/21/1997 12:55
0.32808
59
38
0.03" of rain in the past 72 hours
C9210000
8/13/1997 11:15
0.32808
56
33
0.17" of rain in the past 72 hours
C9210000
9/18/1997 10:50
0.32808
64
30
no rain in the past 72 hours
C9210000
10/28/1997 10:55
0.32808
87
49
1.59" of rain in the past 72 hours
C9210000
11/20/199710:45'
0.32808
100
40
0.01" of rain in the past 72 hours
C9210000, 12/8/1997 12:30
0.32808
64
44 no rain in the past 72 hours
C9210000 1/6/1998 14:45
0.32808
59
289 0.19" of rain in the past 72 hours
C9210000 2/3/1998 11:00
0.32808
74
505 0.34" of rain in the past 72 hours
C9210000 3/5/1998 11:10
0.32808
100
53 no rain in the past 72 hours
C9210000' 4/2/1998 11:30
0.32808
70' 55 0.16" of rain in the past 72 hours
C9210000
5/5/1998 13:15
0.32808
72
56
0.10" of rain in the past 72 hours'
C9210000
6/10/1998 13:40
0.32808
26
541
1.09" of rain in the past 72 hours
C9210000
7/15/1998 11:00
0.32808
96
30
no rain in the past 72 hours
C9210000
8/4/1998 13:30
0.32808
62
36
no rain in the past 72 hours
C9210000
9/2/1998 13:20
0.32808
61
31
no rain in the past 72 hours
C9210000
10/1/1998 13:05
0.32808
65
31
0.16" of rain in the past 72 hours
C9210000
11/5/1998 10:10
0.32808
54
29
0.59" of rain in the past 72 hours
C9210000
12/2/1998 13:20
0.32808
69
27
no rain in the past 72 hours
C9210000
1/4/1999 14:40
0.32808
60.76
64
0.71" of rain in the past 72 hours
C92100001
2/3/1999 11:15
0.32808
65.28
68
0.84" of rain in the past 72 ours
C9210000
3/3/1999 0:00
0.32808' 100
68
0.02" of rain in the past 72 hours I.
C9210000
4/5/1999 0:00 0.32808 85.14
38
0.087" of rain in the past 72 hours
C9210000
5/4/1999 0:00 0.32808, 74.74
36
no rain in the past 72 hours
C9210000
6/3/1999 0:00 0.32808 64
30
no rain in the past 72 hours
C9210000
7/1/1999 0:00 0.328081 521 34
0.16" of rain in the past 72 hours

a
C9210000' 8/5/1999 0:00 0.328081 50 30
no rain in the past 72 hours
C9210000
9/7/1999 0:00 0.32808 ! 64' 32
0.73" of rain in the past 72 hours'
C9210000
10/7/1999 0:00'
0.32808'
50 31
' 0.097" of rain in the past 72 hours
C9210000
11 /3/1999 0:00
0.32808
45.0984 46
0.39" of rain in the past 72 hours
C9210000
12/1/1999 0:001 0.32808' 61.854
34
no rain in the past 72 hours
C9210000
1/3/2000 12:35
0.32808
72.6
32
no rain in the past 72 hours
C9210000
2/1/2000 13:05
0.32808
75.6
95
0.04" of rain in the past 72 hours
C9210000'
3/1/2000 12:50
0.32808
66.64
45
0.71" of rain in the past 72 hours
C9210000
4/3/2000 13:25
0.32808'
64.48 93
0.28" of rain in the past 72 hours
C9210000
5/8/2000 12:45
0.32808
69 38
no rain in the past 72 hours
C92100001
6/8/2000 11:10 0.32808
82
32 0.77" of rain in the past 72 hours
C9210000
7/25/2000 10:20 0.32808
56
41
0.49" of rain in the past 72 hours
C9210000
8/17/2000 15:00
0.32808
54
31,
no rain in the past 72 hours
C9210000' 9/20/2000 12:40
0.32808
64
38
1.12" of rain in the past 72 hours
C9210000 12/19/2000 11:20
0.32808
52
50
0.45" of rain in the past 72 hours

Date
Aug-04
station
DO
_ 7.2
7
8
Cu
I Zn
20!
42
21
inf Cu
eff Cu
Inf Zn
Eff Zn
mc1
upstm of Mcalpine WWTP
34
2.5
96
32
mc2
dwnstm of McMullen/Mcalpine Confluence @ SC2964
2.51_
Ics1
u strm of sugar creek wwtp
2.8 <10
Isc3
dwnstrm of sugar creek wwtp at archdale road
D O
7.1
7.6
7.41
7.2
7.5'
7.5
7.3
- - --
Cu
3.7
21
nr
nr
nr
14
nr
15
23
- '
Eff Zn
-
_
36
ic1
sc1
sc2
sc3
sc4
sc5
mc1
mc2
Ics1
Isc3
upstrm of irwin creek wwtp
2.110
nr
nr
nr
4.5
(<10)
_
dwnstrm of Irwin and sugar confluence at yorkmont rd
dwnstrm of Irwin and sugar confluence at arrowood rd
dwnstrm of Irwin and sugar confluence at nations ford rd
Jul-04
dwnstrm of Irwin and sugar confluence at rte 51
eff Cu
dwnstrm of mcalpine and sugar confluence at rte 160
nr
Zn
inf Cu
Inf Zn
upstm of Mcalpine WWTP
6.4
6.6
8.2
6.8
6.6
39.3
2.8
12.3
dwnstm of McMullen/Mcalpine Confluence Q SC2964
3.3
upstrm of sugar creek wwtp
3.2
0 (<10)
dwnstrm of sugar creek wwtp at archdale road
.4
16
14
ic1
sc4
sc5
mc1
upstrm of irwin creek wwtp
7
7.2
2.5
0 (<10)
dwnstrm of Irwin and sugar confluence at rte 51
4.5
nr
-
dwnstrm of mcalpine and sugar confluence at rte 160
-
7.1
nr
14
15
17
13
20
34
29
28
25
DO
Cu
Zn
inf Cu
eff Cu
Int Zn
Eff Zn
32
Jun-04
[upstm of Mcalpine WWTP
7.4
7.1
7.8
7.3
5.2
0 (<10)
40.8
2.5
119
-
mc2
Ics1
Isc3
ic1
sc4
sc5 -
Imc1
Ics1
Isc3
ic1
sc4
sc5
dwnstm of McMullen/Mcalpine Confluence @ SC2964
DO
3.9
Inf Zn
uupstrm of sugar creek wwtp
5.9
4.4
dwnstrm of sugar creek wwtp at archdale road
--
upstrm of Irwin creek wwtp
7.4
7.4
7.41
8.2
7.9,
7.8
7.9
7.9------.5
7.6
7.8
Cu
4.4
8.3
Zn
eff Cu
•
dwnstrm of Irwin and sugar confluence at rte 51
dwnstrm of mcalpine and sugar confluence at rte 160
May-04
inf Cu
Eff Zn
_mc2
pstm of Mcalpine WWTP
<2.0
4.5
4.6
4.8
<10
dwnstm of McMullen/Mcalpine Confluence @ SC2964
u strm of sugar creek wwtp
dwnstrm of sugar creek wwtp at archdale road
upstrm of irwin creek wwt_p
5.5
dwnstrm of Irwin and sugar confluence at rte 51
dwnstrm of mcalpine and sugar confluence at rte 160

Date
station
DO
Cu
Zn
Aug-03
mc1
upstm of Mcalpine WWTP
7.3
3.2
<10
mc2 .dwnstm
Ics1
of McMullen/Mcalpine Confluence @ SC2964
6.9
3.7
15
13
upstrm of sugar creek wwtp
8
5.5
1
Isc3
dwnstrm of sugar creek wwtp at archdale road
7.4
7.6
4.4
10
_ 1
14
13
id
upstrm of irwin creek wwtp
sc1
dwnstrm of Irwin and sugar confluence at yorkmont rd
sc2
dwnstrm of Irwin and sugar confluence at arrowood rd
sc3
dwnstrm of Irwin and sugar confluence at nations ford rd
sc4
dwnstrm of Irwin and sugar confluence at rte 51
7.2
4.2
16
sc5
dwnstrm of meal ine and sugar confluence at rte 160
7.6
4
4.4
27
Sep-03
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
7.4
20
Oct-03
Nov-03
Dec-03
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
8.6
5.3
24
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
10.1
4.8
25.3
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
11.1 _
DO
7.8
7.4
7.7
_3.6
22
Zn
<10
Date
station
Cu
Jul-03
mc1
upstm of Mcalpine WWTP f
4.2
3.8
mc2
dwnstm of McMullen/Mcalpine Confluence @ SC2964
17
Ics1
upstrm of sugar creek wwtp
3.4
4.8
2.8
6.1
<10
17 - -_
11
21
Isc3
id
dwnstrm of sugar creek wwtp at archdale road
7.9
7.6
u strm of irwin creek wwtp
sc4
--
dwnstrm of Irwin and sugar confluence at rte 51
8.2
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
Date
DO
station
1
Cu
Zn
Jun-03
mc1
upstm of Mcalpine WWTP
7.9
7.9
16
mc2
dwnstm of McMullen/Mcalpine Confluence s SC2964
7.5
8.2
9
7.9
8.2
9.9
16
Cu
3.4
_
19
20
Ics1
pstrm of sugar creek wwtp
Isc3
dwnstrm of sugar creek wwtp at archdale road
8.6
30
25
48
Zn
<10
ic1
u strm of Irwin creek wwtp
8.3
sc4
dwnstrm of Irwin and sugar confluence at rte 51
7.9
Date
sc5
station
_
dwnstrm of mcalpine and sugar confluence at rte 160
•
DO
8.8
May-03
mc1
upstm of Mcalpine WWTP
mc2
dwnstm of McMullen/Mcalpine Confluence @ SC2964
8.6
3.9
17
Ics1
u strm of sugar creek wwtp
9.2
4.4
15
Isc3
dwnstrm of sugar creek wwtp at archdale road
7.6
9.7
4.6
21
id
upstrm of Irwin creek wwtp
3
16
sc4
dwnstrm of Irwin and sugar confluence at rte 51
9.7
1 5.4
1
20
1
sc5
dwnstrm of mcalpine and sugar confluence at rte 160
8.9

Date
station
DO
Cu
Zn
Sep-02
mc1
upstm of Mcalpine WWTP
7.6
2.9
<10
mc2
dwnstm of McMullen/Mcalpine Confluence CO SC2964
7.7
4
3.5
4.6
33
Ics1
upstrm of sugar creek wwtp
8.4
<10
Isc3
id
dwnstrm of sugar creek wwtp at archdale road
8
27
upstrm of irwin creek wwtp
8.4
2.5
<10
sc1
dwnstrm of irwin and sugar confluence at yorkmont rd
sc2
dwnstrm of irwin and sugar confluence at arrowood rd
6.3
sc3
dwnstrm of irwin and sugar confluence at nations ford rd
8.2
sc4
•
dwnstrm of Irwin and sugar confluence at rte 51
25
sc5
sc4
dwnstrm of mcalpine and sugar confluence at rte 160
Oct-02
dwnstrm of irwin and sugar confluence at rte 51
7.7
10.6
4.7
4
23
Nov-02
_
sc4
dwnstrm of irwin and sugar confluence at rte 51
24 -
Dec-02
sc4
dwnstrm of irwin and sugar confluence at rte 51
11.9
4.4
19

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Sugar Permits meeting
/L/C00 7tq5
e4e-tva
Subject: Sugar & Irwin Permits meeting
Date: Mon, 6 Oct 2003 14:25:55 -0400
From: "Gullet, Barry" <[e-mail]>
To: "Jackie Nowell (E-mail)" <[e-mail]>,
"Dave Goodrich (E-mail)" <[e-mail]>
CC: "Jarrell, Jackie" <[e-mail]>,
"Padgett, Dawn" <[e-mail]>,
"Hunter, Tom" <[e-mail]>,
"Purgason, Roy" <[e-mail]>
Jackie and Dave,
I believe that we promised you some info by noon today relative to our
questions about the Sugar & Irwin NPDES Permits. We haven't had time to
finalize a letter or list, but I can share with you the substance of our
interest. We recognize the need to comply with SC water quality standards.
We are ready and willing to do whatever it takes to be sure that the
Charlotte plants do not cause a problem or violation of the SC standards. I
believe we have demonstrated that on the phosphorus issue. However, I need
some more explanation as to what the problem is we are solving with the
metals limits that have been proposed in the draft permits. My
understanding is that the receiving streams in both NC and SC are not
impaired due to these metals at our current levels. We are also a little
confused as to why the stream water hardness data that we have submitted was
not used to calculate the metals limits and we believe that we have found
some errors in the math used to calculate the numbers in the proposed
permit. We would also like to discuss the merits of a study to determine
how metals discharges from Sugar/Irwin are impacting metals in SC streams
and what appropriate limits would be for Sugar/Irwin. This is similar to
the language in the draft permits but we would like to discuss it a little
more.
We have a few other relatively minor items including discussion of a
compliance schedule for compliance with the daily fecal coliform limit, how
the chlorine limits will work when we convert to UV disinfection, etc., but
our main concerns at this time are clearly the metals limits.
See you tomorrow.
1 of 1 10/6/03 5:11 PM

RE: [Fwd: Sugar and Irwin permits]
,1_
Subject: RE: [Fwd: Sugar and Irwin permits]
Date: Wed, 1 Oct 2003 15:58:50 -0400
From: "Jarrell, Jackie" <[e-mail]>
To: "'Jackie Nowell' <[e-mail]>
One other issue I forgot to mention to you was regarding the fecal coliform
limit. We will be able to meet this limit once our UV disinfection is
completed. The project is scheduled to start in Jan. 2004 with completion
in Spring of 2005. This is about as fast as it can be done. The TMDL
established in Mecklenburg County was supposed to be attained through
various improvements (point and nonpoint sources) over a ten year period.
We would just like to have a SOC for the time frame to complete the
construction and installation of the UV. I will send you everything on
Monday. Thanks.
Original Message
From: Jackie Nowell[mailto:[e-mail]]
Sent: Wednesday, October 01, 2003 9:38 AM
To: [e-mail]
Subject: [Fwd: Sugar and Irwin permits]
1 of 1 10/ 1 /03 4:18 PM

CMUD Irwing and Sugar Creek WWTP
Comments from telephone call with Jackie Jarrell
10/ 1 /03
CMU's main concern is the metals. In the calculation for the limits, where did the hardness data,
come from? They take hardness data, 72 hours before and after their discharge. Their hardness
numbers are higher. They are taken at the discharge and is more recent data, taken within the last
6 months.
The fact that there is no reasonable potential for the metals makes it hard to accept the limits for
metals.
The two plants are so far upstream from SC, having to meet these limits so far upstream.
The cost to go to these low limits, they feel it is financially irresponsible. What is the benefit?
The Industries are very concerned because they will be tightened up in their pretreatment
limitations. They are getting organized. IF there is no RP for metals they are very skeptical
about applying limits.
CMU is curious about the calculation for the Ni limits.
The silver limit is below the analytical detection level. NO other silver limits are that low
nationally.
Other comments are small stuff:
Irwin Creek map — pipe 002 is no longer there
Designate in the supp page that the flow equalization basin is complete.
At Sugar Creek, the backup power is complete.
Boilerplate language- cannot be changed at this time by NPDES
Need form for submitting P calculations.

Ja�tea ST‘T4s
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
Arl— YW REGION 4
�%% ATLANTA FEDERAL CENTER
61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960
S E P 2 3 2003
� 4.e
r•1 PRot-0
-SEP 1 9 2003
Mr. Dave Goodrich, Supervisor
NPDES Unit
Division of Water Quality
North Carolina Department of Environment
and Natural Resources
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
SUBJ: Review of Proposed Final NPDES Permits
Charlotte Mecklenburg Utilities
Irwin Creek WWTP
NC0024945
Dear Mr. Goodrich:
The Environmental Protection Agency (EPA) Region 4 has received the proposed final
National Pollutant Discharge Elimination System (NPDES) permit on September 8, 2003, for the
above referenced facility. In accordance with the EPA/NC Memorandum of Agreement, we have
no comment on the proposed final permit as it addresses EPA's March 28, 2002, objections to
the February 13, 2002, draft permit.
The permit includes a schedule of compliance in order to evaluate options for meeting
copper, zinc, and silver NPDES permit limits. It allows for the evaluation of a site -specific
criterion consistent with "Interim Guidance on Determination and Use of Water -Effect Ratios for
Metals" EPA-823-B-94-001, February 1994. Derivation of a water -effect ratio is considered a
site specific criterion adjustment subject to EPA review and approval/disapproval under Section
303(c) of the Clean Water Act. If the facility chooses to evaluate a site -specific criterion in
accordance with this EPA document, then EPA Region 4 requests that the individual water -effect
ratio derived by the State, be submitted to EPA Region 4 for review and approval. Additionally,
since this permit affects a downstream state, EPA suggests the water -effect ratio also be
submitted to South Carolina Department of Health and Environmental Control, Water Permits
Division, for review and comment prior to implementation.
Internet Address (URL) • http://www.epa.gov
Recycled/Recyclable • Printed with Vegetable 00 Based Inks on Recycled Paper (Minimum 30% Postconsumer)

2
EPA requests that we be afforded an additional review opportunity only if any other
significant changes are made to the permit prior to issuance, or if significant objections to
the permit are received. Otherwise, please send us one copy of the final permit when issued.
Thank you for your attention to the issues regarding the Charlotte Mecklenburg Utilities -
Irwin Creek NPDES permit. If you have any questions, please feel free to contact me directly
or Ms. Dee Stewart at 404/562-9334.
Sincerely,
J. Scott Gordon, Chief
Permits Grants & Technical Assistance Branch
Water Management Division
cc: Ms. Jacqueline Jarrell
Charlotte Mecklenburg Utilities District
Alton Boozer, SCDHEC

D
H E C
PROMOTE PROTECT PROSPER
2600 Bull Street
Columbia, SC 29201-1708
COMMISSIONER:
C. Earl Hunter
BOARD:
Bradford W. Wyche
Chairman
Mark B. Kent
Vice Chairman
Howard L. Brilliant, MD
Secretary
Carl L. Brazell
Louisiana W. Wright
L. Michael Blackmon
Lany R. Chewning, Jr., DMD
September 15, 2003
Ms. Jacquelyn M. Nowell
NPDES Unit
N.C. Dept. of Environment and Natural Resources
P.O. Box 29535
Raleigh, NC 27626-0535
RE: Sugar/Irwin CMUD Permits
Your letters of September 1, 2003
Dear Ms. Nowell:
0 1
-i
SEP 1 9 2003
Thank you for factoring in our input. We offer no other comments with these
final draft permits. We would appreciate an opportunity to critique a site
specific study for metals if proposed for a permit modification in the future
with these permits.
I can be reached at 803-898-4157 or at [e-mail].
Since
Jeffrey P. deBessonet, P.E., Director
Water Facilities Permitting Division
cc: Mike Montebello
SOUTH CAROLINA DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL

SUMMARY OF CMUD/DWQ/SCDHEC
SETTLEMENT AGREEMENT
INTRODUCTION
In the summer of 2001, the South Carolina Department of Health and Environmental
Control (SCDHEC) filed a Petition for a Contested Case in the North Carolina Office of
Administrative Hearings regarding the renewal of NPDES Permit No. NC0024970, the Charlotte
Mecklenburg Utilities Department (CMUD) McAlpine Creek Wastewater Treatment Plant. The
primary complaint on the part of SCDHEC has been that the permit was renewed without a
phosphorus limit. Nearly all of South Carolina's municipal dischargers to the mainstem Catawba
(upstream of Lake Wateree) have been given phosphorus limits, generally equivalent to 1 mg/L.
The McAlpine Creek WWTP permit had a phosphorus optimization study special condition that
stipulated preparatory requirements for the facility to ready itself for the upcoming phosphorus
Total Maximum Daily Load (TMDk)
Since the summer, SCDHEC, the North Carolina Division of Water Quality (NCDWQ)
and CMUD have been working towards achieving consensus on an appropriate phosphorus limit
for the McAlpine Creek WWTP. The understanding has been that this decision will also affect
DWQ's permitting strategy for'three additional municipal permits: CMUD - Irwin Creek WWTP,
CMUD - Sugar Creek WWTP, anAinion County - 12-Mile Creek WWTP.
The final settlementagreement includes the terms of the limits for all three CMUD
plants. A similar strategy will be used by DWQ .to limit phosphorus in the Union County permit.
SUMMARY OF SETTLEMENT AGREEMENT
Limits at McAlpine Creek WWTP
Based upon a construction schedule provided by CMUD during the settlement
proceedings, the compliance date for the total phosphorus limit at the McAlpine Creek WWTP is
set for February 28, 2006. At this time, the McAlpine Creek WWTP must meet a 534 lbs./day
total phosphorus limit. This limit is to be calculated as a 12-month rolling average. It
corresponds to a 1 mg/L limit at McAlpine Creek's permitted flow of 64 MGD.
This limit, as well as the monthly mass cap described below, shall be incorporated into a
major modification to NPDES Permit NC0024970 with special condition language to be included
with reference to the Irwin and Sugar Creek WWTPs. Since SCDHEC's stipulation was that any
;limit come into effect prior to the expiration date of the permit, the permit expiration date will
also be modified to February 28th, 2006 (instead of June 30, 2005). This puts the permit out of
sync with the Basinwide schedule, but is within the five years allowable for a permit term under
federal regulations.
Bubble Limit
A major point of the settlement agreement is the idea of a bubble limit. This refers to a
mass limit for total phosphorus that applies to discharge at the three CMUD plants combined.
This type of a limit would give CMUD more operational flexibility with regard to phosphorus
removal.
The bubble limit, to be calculated as a 12-month rolling average, is 826lbs./day of total
phosphorus from all three CMUD plants. This corresponds to a 1 mg/L phosphorus limit at
permitted discharge for the three plants. If CMUD conducts construction activities at either the
Sugar or Irwin Creek plants, the compliance date for this bubble limit will be February 28, 2007.

If CMUD decides not to conduct construction activities at either plant in order to achieve
compliance, the bubble limit will come into effect on February 28, 2006. This is identical to the
compliance date at the McAlpine Creek plant.
Special condition language will be included in the Irwin and Sugar Creek WWTP permits
regarding the compliance date.
Mass cap
In order to be protective of the water quality at the downstream lakes in South Carolina,
SCHEC requested that monthly mass caps also be included as part of the total phosphorus limits
at the three CMUD plants. This would also ensure optimized operation of the plants at all times.
The mass caps at the three plants take the form of a monthly average mass limit and
correspond to a concentration limit of 2 mg/L at maximum permitted flow. At McAlpine Creek,
this limit is 1,0671bs. /day of total phosphorus beginning February 29, 2006. At the Sugar and
Irwin Creek plants, the mass caps only come into effect if construction activities are pursued at
each plant. At Sugar Creek WWTP, the limit is 334 lbs./day with compliance commencing on
February 28, 2007. At Irwin Creek WWTP, the limit is 250lbs./day with compliance
commencing on February 28, 2007.
TMDL
As part of the settlement agreement DWQ requested a provision for full inclusion in the
TMDL process for both DWQ and all affected NC entities (to be provided in a list by DWQ).
APPLICABILITY TO PERMITTING PROCESS
The three CMUD permits will have the bubble limit included as a special condition.
Monitoring for phosphorus will be included in the regular effluent limit pages. Mass caps will
also be included in the effluent limit pages, with a footnote specifying applicability (for Sugar and
Irwin Creek plants) and compliance dates.
The Union County - 12 Mile Creek WWTP shall have a mass limit equivalent to 1 mg/L
at the permitted flow. As with the three CMUD plants, compliance for this limit is to be judged
as a rolling annual average. Special monitoring language is being developed for this situation. It
is also recommended that the phosphorus optimization study special condition from the original
McAlpine Creek WWTP permit be included in this permit to allow DWQ time to review the
County's preparations for the impending phosphorus TMDL.
3.6h(5
( nti/t

Permit NC0024970
• A.(5.) NUTRIENT STUDY
The South Carolina Department of Health and Environmental Control (SC DHEC) has
determined that Fishing Creek Reservoir, Cedar Creek Reservoir and Lake Wateree are impaired due
to excessive nutrient loads and algal response to discharges upstream of these lakes. The Catawba
River Basinwide Water Quality Plan (December 1999) states that a TMDL will be developed to address
the causes and sources of impairment in these South Carolina lakes. SC DHEC has proposed the
development of a phosphorus TMDL and is planning to limit phosphorus for all South Carolina
NPDES dischargers with flows greater than 50,000 gallons per day. Significant discharges of
phosphorus have also been linked to the North Carolina portion of the Fishing Creek Reservoir
watershed. Estimates indicate that a significant portion of the total phosphorus load comes from the
Sugar Creek Subbasin. To work towards reduction of this load, CMUD shall provide the Division
with a study that fully investigates the feasibility of reducing total phosphorus (TP) load at this
WWTP. The target TP load should be equivalent to a TP concentration of 1 mg/L at the effluent This
condition should not be construed as a permit limit However, a limit may be imposed once the TMDL
has been completed and an implementation plan is developed.
The optimization study should include the following:
• An identification of significant sources of pollution in the system.
• An evaluation of ways in which these sources can be reduced or eliminated.
• The possibility of reducing influent flows to the WWTP to control mass loading to the
stream.
• An assessment of the current treatment processes and ways in which this may be
optimized to achieve a higher level of treatment.
• A plan to optimize the current treatment system to achieve a higher level of nutrient
removal.
• An evaluation of additional treatment units required to achieve higher nutrient removal.
The optimization study should be completed by February 1, 2002, and submitted to the following
address:
North Carolina Division of Water Quality
Water Quality Section/NPDES Unit
1617 Mail Service Center
Raleigh, North Carolina 27699-1617

Permit NC0024970
A. (2.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS — FINAL
During the period beginning on February 28, 2006 and lasting until expiration, the Permittee is authorized to
discharge from outfall 001. Such discharges shall be limited and monitored by the Permittee as specified below:
Flow
M00,l
Averaq
64.0 MGD
Continuous
Recording
I or E
CBOD, 5-day (20°C)2
April 1- October 31
4.0 mg/L
6.0 mg/L
Daily
Composite
E, I
CBOD, 5-day (202C)2
November 1- March 31
8.0 mg/L
12.0 mg/L
Daily
Composite
E, I
Total Suspended Residue2
15.0 mg/L
22.5 mg/L
Daily
Composite
E, I
NH3 as N (April 1- October 31)
1.0 mg/L
Daily
Composite
E
NH3 as N (November 1-March 31)
1.9 mg/L
Daily
Composite
E
Dissolved 0xygen3
Daily
Grab
E, U, D
Fecal Coliform
(geometric mean)
200/100mi
400/100m1
Daily
Grab
Total Residual Chlorine's
17 µg/L
Daily
Grab
Temperature (2C)
Daily
Grab
E, U, D
Total Nitrogen (NO2 + NO3 + TKN)
Monthly
Composite
E
Total Phosphoruss
Monthly Average: 1,067.0 lbs./day
12-month Average: 534 lbs./day
Monthly
Composite
Chronic Toxicity6
Quarterly
Composite
Conductivity
Daily
Grab
E, U, D
Chromium
Lindane
51 p.g/L
204 µg/L
0.01 µg/L
Weekly
Weekly
Composite
Grab
E
E
Copper
2/Month
Composite
E, U, D
Cyanides
5 µg/L
15 µg/L
Weekly
Grab
E
Lead
26 µg/L
34 µg/L
Weekly
Composite
Silver
2/Month
Composite
Zinc
2/Month
Composite
E, U, D
Mercury8
0.012 µg/L
Weekly
Composite
E
Molybdenum
2/Month
Composite
E
Footnotes:
1 Sample Locations: E - Effluent, I - Influent, U - Upstream, D- Downstream. For instream monitoring
requirements, see Part A.(3.).
2 The monthly average effluent CBOD5 and total suspended residue concentrations shall not exceed 15% of the
respective influent value.
3 The daily average dissolved oxygen effluent concentrations shall not be less than 6.0 mg/L.
4 The daily average limit for total residual chlorine shall be 28 µg/L.
5 The 12-month average limit will remain in effect until such time as the "bubble limit" stipulated in Part A.(5.)
comes into effect. Once the bubble limit is effective, the 12-month average limit is 826 lbs./day for all three
CMUD plants (McAlpine, Irwin and Sugar Creek WWTPs) combined. See Part A.(5.). for additional
informationon the bubble limit. Part A.(6.) describes the methodology for calculation of the monthly average
and 12-month limits.
6 Whole effluent toxicity shall be measured by Chronic Toxicity (Ceriodaphnia) P/F at 90 %. Samples shall be
taken quarterly during the months of March, June, September and December. See Part A.(4.).
7 The Division of Water Quality shall consider all cyanide concentrations reported below 10 ug/L to be "zero" for
permit -compliance purposes only.
8 The quantitation limit for mercury shall be 0.2 ug/1 (0.2 ppb). Levels reported at less than 0.2 ug/1 shall be
considered zero for compliance purposes. •
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Sugar and Irwin Draft Permits
Subject: Sugar and Irwin Draft Permits
Date: Fri, 2 May 2003 16:48:13 -0400
From: "Jarrell, Jackie" <[e-mail]>
To: "'[e-mail]"' <[e-mail]>
Thanks Jackie for talking to me about these draft permits. Here are the
questions posed at the conference call last September that Dave G. was going
to send us documentation (from the file) that the limits were based on.
1. What limits are based on South Carolina water quality standards? Dave
was going to confirm after looking at file
2. Have DHEC and EPA determined that the Sugar and Irwin discharges would
cause a violation of the South Carolina water quality standards? Did EPA
conclude that discharges from Sugar and irwin without limits for these
pollutnats would have an undue impact on interstate waters? NCDENR (Dave)
was going to provide information back to us - fact sheet
3. How did DHEC and EPA make that determination? Who was involved in making
that determination? Can we talk to those people? Can we get copies of all
,A documents relating to that determination?
4. Did DHEC consider any historic effluent sampling results for these
constituents in making this determination?
CMUD (We) never saw the comments from EPA and SCDHEC sent back to NCDENR on
the original proposed draft permit (March 2002 draft). Then we got the new
proposed draft June 28, 2002 with changes based on their comments. We would
like to see there comments that they sent in.
Thanks again and let me know if you want to meet to talk about all this.
Jackie Jarrell
Environmental Management Division
Charlotte Mecklenburg Utilities
4000 Westmont Drive
Charlotte, NC 28217
[phone]
[e-mail]
7o' . 63N -spa ("19
5/2/03 5:21 PM

.�J
JacZEO S) 1
A Yv
2 Z
1111Pe
144 PROS G
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET
ATLANTA, GEORGIA 30303-8960
M . Coleen Sullins, Chief
ater Quality Section
C Dept. of Environment and
Natural Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
APR 0 2 2003
SUBJ: Status of NPDES Permits
Irwin Creek WWTP, NC0024945
Sugar Creek WWTP, NC0024937
Dear Ms. Sullins:
D'1
The Environmental Protection Agency (EPA) Region 4 received proposed final National
Pollutant Discharge Elimination System (NPDES) permits on June 27, 2002, addressing EPA's
March 28, 2002, objections to the February 1, 2002, draft permits for the facilities listed above.
EPA withdrew our objections to both permits in letters dated July 2, 2002.
To date, according to EPA's backlog tracking report, these permits have not been issued.
Since these permits affect South Carolina and based on EPA's previous concerns with their
contents, EPA Region 4 requests an update on the status of issuance of these permits. EPA, per
our July 2, 2002, letter withdrawing our objections and in accordance with the Memorandum of
Agreement between North Carolina and EPA Region 4, requests that we be afforded an additional
review opportunity for these permits if significant changes are made to the permits prior to
issuances, or if significant objections to the permit are received.
Please provide this update by May 1, 2003. Thank you for your attention to the issues
regarding the Charlotte Mecklenburg Utilities Irwin and Sugar Creek NPDES permits. If you
have any questions, please feel free to contact me or have your staff contact Ms. Dee Stewart, of
my staff, at 404/562-9334.
Sincerely,
J. Scott Gordon, Chief
Permits, Grants, and Technical Assistance Branch
Water Management Division
cc: Ms. Jacqueline Jarrell
Charlotte Mecklenburg Utilities District
Alton Boozer, SCDHEC
Internet Address (URL) • http:/Jwww.epa.gov •
Recycled/Recyclable • Printed with Vegetable O1 Based Inks on Recycled Paper (Minimum 30% Postconsumer)

' Amanda Kitchen
From: Jarrell, Jackie [[e-mail]]
Sent: Wednesday, June 26, 2002 3:03 PM
To: Gullet, Barry; Boyd, Mike; Benne Hutson
Cc: Bean, Douglas; Padgett, Dawn; Zabec, Myra; Hunter, Tom; Purgason, Roy
Subject: FW: Sugar and Irwin Creek Proposed Final NPDES Permits
Irwin draft
permitvl.2.doc
Sugar draft
permitvl.2.doc
FYI
Original Message
From: Mike Myers (mailto:[e-mail]]
Sent: Wednesday, June 26, 2002 2:48 PM
To: Dee Stewart
Cc: [e-mail]; Dave Goodrich; Jacqueline Jarrell;
Jeff deBessonet; Michael Montebello
Subject: Sugar and Irwin Creek Proposed Final NPDES Permits
Attached are the "Proposed Final Permits" for the Sugar and Irwin Creek
NPDES permits. EPA should receive hard copies on Thursday (June
27th). This will satisfy the requirements of 40 CFR 123.44 h(1), which
stipulates that the state must resubmit a revised permit to meet the
Regional Administrator's objections within 90 days of receipt of the
objection. Since the Division received the objection letter on April 2,
2002, the deadline for resubmittal of the revised permit is July 1,
2002.
Please note that the schedule of compliance language for copper, silver
and zinc has been modified, based on EPA comments. It is my
understanding that these changes to the draft permit satisfy the EPA and
South Carolina objections to the draft permit.
The attached permits are for informational purposes only and are not
considered the formal issuance of the permits to Charlotte.
Thanks for your comments and review.
Mike Myers
NC DWQ
NPDES Unit

�•
J�ieo sr,1�s
A UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
�� >W REGION 4
o Q ATLANTA FEDERAL CENTER
x3F�1� c4) 61 FORSYTH STREET
tir4( PFICOG� ATLANTA, GEORGIA 30303-8960
JUL 0 2 2002
Alan W. Klink, Director
Division of Water Quality
North Carolina Department of Environment and
Natural Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
SUBJ: Review of Proposed Final NPDES Permit
Irwin Creek WWTP
NC0024945
Dear Mr. Klimek:
The Environmental Protection Agency (EPA) Region 4 has received the proposed final
National Pollutant Discharge Elimination System (NPDES) pen -nit on June 27, 2002, for the
above referenced facility. In accordance with the EPA/NC Memorandum of Agreement, we have
no objection to the issuance of the proposed final permit as it addresses EPA's March 28, 2002,
objections to the February 13, 2002, draft permit. EPA requests that we be afforded an
additional review opportunity only if any other significant changes are made to the per nit prior
to issuance, or if significant objections to the permit are received. Otherwise. please send us one
copy of the final permit when issued.
Thank you for your attention to the issues regarding the Charlotte Mecklenburg Utilities -
Irwin Creek NPDES permit. The effort extended by your staff to work with EPA Region 4, the
State of South Carolina, and Charlotte Mecklenburg Utilities toward an effective resolution is to
be commended. If you have any questions, please feel free to contact me or have your staff
contact Ms. Dee Stewart, of my staff at 404/562-9334.
Beverly H. Banister, Director
Water Management Division
cc: Ms. Jacqueline Jarrell
Charlotte Mecklenburg Utilities District
Alton Boozer, SCDHEC
Internet Address (URL) • http:/lwww.epa.gov
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SCDHEC Ammonia Toxicity Calculation
Based on 1999 EPA Water Quality Criteria for Ammonia as adopted by S.C. DHEC R.61-68
promulgated December 14, 2000 pending approval by S.C. Genera! Assembly and U.S. EPA
Division of Water Quality
April 23, 2001
Discharger Name:
Receiving Stream:
Date:
Analyst:
CMUD - Irwin Creek
Irwin Creek
May 15, 2002
Michael Myers
Input Data
Upstream Flow (cfs):
Upstream Total Ammonia Concentration (mg N/L):
Stream Temperature, Summer (deg. C):
Stream Temperature, Winter (deg. C):
Stream pH:
Discharge Flow (mgd):
Are Salmonids Present? (yes/no):
Are Fish ELS Present? (yes/no):
4.9
0.22
26
13
7.5
15
No
Yes
Instream Total Ammonia Toxicity Results
Season:
Criterion Maximum Concentration, CMC (mg N/L):
Criterion Continuous Concentration, CCC (mg NIL):
Summer
19.890
2.082
Winter
19.890
4.364
Discharge Total Ammonia Results
Season:
Max. Conc. Protecting Against Acute Toxicity (mg N/L): 24.04
Max. Conc. Protecting Against Chronic Toxicity (mg N/L): 2.47 5.24
Summer
Winter
24.04

United States Department of the Interior
U.S. GEOLOGICAL SURVEY
3916 Sunset Ridge Road
Raleigh, North Carolina 27607
April 17, 2002
Mr. Michael Meyers, Environmental Engineer
N.C. Division of Water Quality
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Dear Michael:
C.-
In response to your request for low -flow data, the U.S. Geological Survey (USGS) provides the following infor-
mation for the continuous -record gaging stations at Sugar Creek at NC 51 near Pineville (station id 02146381,
drainage area 65.3 mi2, period of record October 1994 through current) and Little Sugar Creek at Hwy 51 at
Pineville (station id 02146530, drainage area 49.2 mi2, period of record June 1997 through current). The low -
flow characteristics have been estimated by correlating the runoff characteristics at these short-term gaging sta-
tions with nearby long-term continuous -record gaging stations on Long Creek and McAlpine Creek. Please note
that while flow estimates were adjusted to account for the effects of major effluent discharges from upstream
wastewater treatment plants, the estimates do not account for the presence of any other diversions or regulation,
present or future, which may occur upstream of the gages.
Enclosed is a table of the low -flow characteristics at the request sites on Sugar Creek and Little Sugar Creek as
well as nearby index sites at Long Creek near Paw Creek (station id 02142900, drainage area 16.4 mi2) and
McAlpine Creek at Sardis Road near Charlotte (station id 02146600, drainage area 39.6 mi2). Additionally, the
table also present low -flow characteristics for three selected gaging stations in the Charlotte area with flows not
known to have been affected by significant diversions upstream of the sites.
Low -flow characteristics for the request sites are presented for flow conditions that (1) include the National Pol-
lutant Discharge Elimination System (NPDES) discharges from upstream wastewater treatment plants (WWTP)
on Irwin and Little Sugar Creeks as recorded at the gages, and flow conditions that (2) do not include the NPDES
discharges from these facilities (computed by subtracting the concurrent daily WWTP discharges from the daily
mean discharges recorded at the gages). Comparison of the NPDES discharge records for the periods of records
at the request sites indicated that effluent discharges accounted for 31.5 and 48.8 percent of the flows at the Sugar
Creek and Little Sugar Creek sites, respectively.
At the request sites, low -flow discharge yields, expressed in units of (ft3/s)/mi2 of drainage area, were found to
be comparable for those discharges that do not include the effects of the NPDES discharges. However, these
yields cannot necessarily be considered indicative of true "natural -flow" conditions that would be expected if
there were no urbanization effects in the basins.
Thank you for your assistance in obtaining the records of daily NPDES discharges for the facilities on Irwin
Creek and Little Sugar Creek. Please note that these data are preliminary and subject to revision pending
approval for publication by the Director of the U.S. Geological Survey, and are made available through the coop-
erative program of water -resources investigations with the North Carolina Department of Environment and Nat-
ural Resources.
If you have any questions regarding this information, please contact me at [phone].
Sincerely,
7700(g
J. Curtis Weaver
Hydrologist
Enclosure
Copy to: Mr. Jerald B. Robinson, USGS, Charlotte, NC
[phone] • FAX [phone]

Table 1. Magnitude and frequency of annual low -flow characteristics at selected continuous -record gaging stations in
City of Charlotte and Mecklenburg County, North Carolina
[mil, square mile; climatic years, the annual period from April 1 to March 31 and identified by the year in which the period begins; (ft3/s)/mi2,
cubic foot per second per square mile; ft3/s, cubic foot per second; 7Q10, 7-day, 10-year low flow; 30Q2, 30-day, 2-year low flow; W7Q 10, winter
7-day, 10-year low flow; 7Q2, 7-day, 2-year low flow; NC, North Carolina highway; Hwy, highway; PR, gaging station having less than 10 years
record of daily mean discharge, treated as a partial -record site where low -flow characteristics were developed by using correlation techniques;
WWTP, wastewater treatment plant. Values shown in parentheses below each low -flow discharge are the corresponding low -flow yields in (ft3/s)/
mil
Station name
a Low flow characteristics
co E (ft3/s)
a' E w o
Cis) E O 0 O N v N
G 6 Q M 0
0 V.
Comments
Request sites
02146381 Sugar Creek at NC 51 near 65.3 PRa 11.0 24.3 21.1 18.2 Includes the NPDES dis-
Pineville (0.1685) (0.3721) (0.3231) (0.2787) charges from Irwin Creek
WWTP
PRa 4.7 13.0 10.8 8.9 NPDES discharges from
(0.0720) (0.1991) (0.1654) (0.1363) Irwin Creek WWTP
removed from record
02146530 Little Sugar Creek at Hwy 51 at 49.2 PRb 13.2 20.1 24.5 21.2 Includes the NPDES dis-
Pineville (0.2679) (0.4085) (0.4980) (0.4309) charges from Sugar Creek
WWTP
PRb 3.1 9.6 7.8 6.3 NPDES discharges from
(0.0630) (0.1951) (0.1585) (0.1280) Irwin Creek WWTP
removed from record
Nearby index sites
02142900 Long Creek near Paw Creek 16.4 1966- 0.7 1.9 1.7 1.3 No known significant
2000 (0.0433) (0.1177) (0.1018) (0.0811) diversions or regulation
upstream of gaging sta-
tion c
02146600 McAlpine Creek at Sardis Road 39.6 1962- 1.1 4.5 3.4 2.7 No known significant
near Charlotte 2000 (0.0268) (0.1144) (0.0856) (0.0674) diversions or regulation
upstream of gaging sta-
tion.
Other nearby sites
02146211 Irwin Creek at Charlotte
5.97 1982-93, 0.3 0.8 0.7 0.5 No known significant
1998-99 (0.0419) (0.1357) (0.1173) (0.0871) diversions or regulation
upstream of gaging sta-
tion.
02146450 Briar Creek at Sharon Road at 18.5 1962-72 1.1 3.3 2.2 1.8 No known significant
Charlotte (0.0616) (0.1773) (0.1200) (0.0957) diversions or regulation
upstream of gaging sta-
tion.
02146500 Little Sugar Creek near
Charlotte
41.0 1925-49e 3.8 9.5 5.5 6.6 No known significant
(0.0924) (0.2327) (0.1351) (0.1607) diversions or regulation
upstream of gaging sta-
tion.
a. Available period of record (October 1994 through early April 2002) used in analysis.
b. Available period of record (June 1997 through early April 2002) used in analysis
c. A diversion for irrigation purposes is known to occur in the Long Creek basin upstream of the gaging station, but the diversion
amount has not been quantified and is not currently known to be significant (Jerald B. Robinson, USGS, oral commun., April 17, 2002).
d. Low -flow characteristics for these sites are presented to provide some indications of low -flow yields (in parentheses) of streams in
the Charlotte area that are not known to have had significant diversions upstream of the site.
e. For the gaging station at Sta. 02146500, the period of analyses was selected on the assumption that effects of urbanization on flows
were minimal during the period. The full period of record for this site is July 1924 through December 1977.

J,,,tE rFs.
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
z�yW REGION 4
i Q ATLANTA FEDERAL CENTER
61 FORSYTH STREET
yTgt PAOZEGUAR 2 Z1J'eb ATLANTA, GEORGIA 30303-8960
Mr. Dave Goodrich, Supervisor
NPDES Unit
Division of Water Quality
North Carolina Department of Environment and
Natural Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
SUBJ: NPDES Permit for CMUD Irwin Creek WWTP
Permit No. NC0024945
Dear Mr. Goodrich:
12�0�1
AP
A _ 2 20C2 �
DENR - WATER QUALITY
POINT SOURCE BRANCH
We have completed our review of the draft National Pollutant Discharge Elimination
System (NPDES) permit dated February 13, 2001, and provided informal comments in an e-mail
dated March 13, 2001. EPA Region 4, also requested a review extension until March 29, 2001,
in the same e-mail. Due to some deficiencies in the revised draft permit conditions, EPA
objections and comments are detailed below, pursuant to Section III.B.1 of the North
Carolina/EPA Memorandum of Agreement (MOA) and federal regulations.
Based on the reasonable potential analysis conducted by North Carolina and submitted
with the permit and fact sheet, total copper, total zinc, and total silver are reported as a maximum
predictable effluent concentration of 62.3 ug/1, 82.6 ug/1, and 5.7 ug/1, respectively. The draft
permit does not contain numeric limits for these parameters since North Carolina has action
levels.
However, this discharge affects waters in the State of South Carolina. Therefore, our
review also focused on protecting the water quality criteria and standards of that State. EPA did
not find hardness data in the application and assumed a hardness of 25 mg/1 as CaCO, and used
an in -stream waste concentration of 83% for the Irwin Creek Plant. EPA's calculations for the
resulting maximum allowable end -of -pipe values that meet South Carolina numeric criteria are:
total copper - 4.8 ug/1 (acute) and 4.3 ug/1 (chronic), total zinc - 36.0 ug/1 (acute) and 39.5 ug/1
(chronic), and total silver - 0.37 ug/1 (acute) (no chronic criterion exists).
Based on the available information, comparing the maximum predicted effluent
concentrations to the maximum allowed values indicates that reasonable potential exists to
exceed South Carolina water quality standards for these three pollutants. EPA objects to the lack
of specific numeric limits for total copper, total zinc, and total silver in this draft permit. Per 40
C.F.R. § 122.4(d) and 40 C.F.R. § 122.44(d)(4), no permit can be issued whose conditions
cannot ensure compliance and conforrnity with applicable water quality standards of an affected
state.
Internet Address (URL) • http://www.epa.gov
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2
Regarding fecal coliform, the draft permit's monthly and weekly average limits do
comply with North Carolina's water quality standards. However, South Carolina's freshwater
water quality standards for fecal coliform include a requirement that no more than 10%
of the total monthly samples exceed 400/100 ml. South Carolina municipal permits typically
protect this provision through a daily maximum fecal coliform limit of 400/100 ml. Because the
draft permit's fecal coliform limits do not reflect South Carolina's fecal coliform standards, EPA
objects per 40 C.F.R. § 122.4(d) and 40 C.F.R. § 122.44(d)(4).
All POTWs are required, unless impracticable, to include average weekly and average
monthly discharge limitations [40 C.F.R. § 122.45(d)(2)]. The draft permit does not include a
weekly average limit for ammonia. EPA, Region 4, recognizes that this is an issue that is
awaiting resolution in many NPDES permits in North Carolina. If left unresolved, the ammonia
provisions of this draft permit will be subject to EPA objection.
The mercury detection limit is recommended to be at a minimum of 0.2 ug/1 in the draft
permit. This is inconsistent with EPA -approved Method 1631C (and Method 1669) which has a
detection limit for mercury of 0.0005 -ug/1. The recent North Carolina Inspector General (IG)
report documented that the State should require more sensitive analytical methods as they
become available. The use of a 0.2 ug/l rather than a 0.0005 ug/1 detection limit is not consistent
with the IG's recommendation. Additionally, North Carolina Water Quality Standards list a
mercury criterion of 0.012 ug/1 and the use of a 0.2 ug/1 detection limit is not sufficient to
determine compliance with the North Carolina criterion. Further, Part II.D.4 of North Carolina's
boilerplate permit language states that the permittee will be required to use test procedures that
produce minimum detection and reporting levels that are below the permit discharge
requirements and all data generated must be reported down to the minimum detection or lower
reporting level of the procedure. Because EPA Method 1631C (and Method 1669) which has an
appropriately sensitive detection limit is not specified in the draft permit, EPA objects per 40
C.F.R. § 136, 40 C.F.R. § 122.41(j)(1) and (4), and 40 C.F.R. § 123.44(c)(5).
EPA Region 4 also offers the following comments. The permit settlement language has
not been included in the draft permit for the Charlotte -Mecklenburg Utility Department (CMUD)
Irwin Creek facility referenced in the January 18, 2002, agreement between the South Carolina
Department of Health and Environmental Control, the North Carolina Department of
Environment and Natural Resources, CMUD, and the North Carolina Environmental
Commission. EPA requests that this language be incorporated, as well as a 2007 expiration date.
We request that you redraft the permit to address the objections expressed above and
submit a proposed NPDES permit to EPA for review under the provisions of Section III.B.3 of
the MOA. If you have any questions, please call Ms. Dee Stewart at [phone].
Sincerely,
J. Scott Gordon, Chief
Permits, Grants, and Technical Assistance Branch
Water Management Division
cc: CMUD

CIttU 7
(CIX�
C LOTT' ..
March 19, 2002
Michael J. Myers
NPDES Unit
Division of Water Quality
North Carolina Department of Environment
and Natural Resources
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Re: NPDES Draft Permits
Permit Nos. NC0024945 and NC0024937
CMUD — Irwin Creek and Sugar Creek
Mecklenburg County
Dear Mr. Myers:
By this letter, Charlotte Mecklenburg Utilities is providing its comments on these
two draft permits. These draft permits were sent to us under cover letters dated February
13, 2002, both of which we received on or about February 18, 2002. These comments are
being provided within the 30-day public comment period established by the Division.
For ease of review, our comments are referenced either to the headings used in
your cover letters or to specific provisions of the draft permits.
Amendment to the NPDES Permit Application
You have requested that Charlotte Mecklenburg Utilities sign certifications that
summaries of data from our discharge monitoring reports are, to the best of our
knowledge, "true, complete and accurate." Based on our review, there are errors in the
summaries. As a result, we cannot sign the certification
Possible Future Ammonia Limitations
Your letter states that EPA and the Division are currently discussing the need for
weekly average and daily maximum ammonia limitations. If such limits are determined
to be necessary, they can only be implemented as a major modification to these permits.
This would require the Division to prepare a Reasonable Potential Analysis for ammonia
in surface waters that could be affected by the discharge as well as giving Charlotte
Mecklenburg Utilities and the public opportunity to comment on the modification during
Engineering Division 5100 Brookshire Boulevard Charlotte, NC 28216 704/399-2551
Charlotte -Mecklenburg Utility Department

a mandatory public comment period. Please confirm that the Division agrees that any
such changes will be major modifications and that the Division will comply with all legal
and regulatory requirements applicable to such modifications.
If at all possible, we would like to be involved in the discussions with the
Division and EPA on the possible establishment of ammonia limits. As you are well
aware, involving us in the negotiations with the Division and South Carolina was the key
to reaching the historic settlement on reducing phosphorous discharges since we were the
ones who had to come up with the plan and the financing to achieve such reductions.
There is every reason to believe our involvement on possible ammonia limits would be
just as helpful and productive.
Irwin Creek — Chromium Monitoring
40 CFR section 122.44(d) basically allows the State to impose monitoring
requirements and effluent limitations when the State determines that a discharge has a
"reasonable potential to cause" a violation of a water quality standard. The procedures
used to make such a determination must comply with 40 CFR section 122.44(d)(1)(ii). In
light of this regulatory standard, please explain the basis for adding a requirement for
chromium monitoring as a condition for the Irwin Creek permit when, according to your
cover letter, the "reasonable potential analysis indicates no reasonable potential...
v Status of Irwin Creek and Status of Little Sugar Creek
In both of these sections of the cover letters, the Division states that these creeks
appear on the 303(d) list of impaired streams. Please identify what problem parameters
have resulted in each of these streams being put on the 303(d)list.
Second, both letters state that "non -point sources are the main contributor to this
degradation" that has led to the 303(d) listing. However, both letters then go on to state
that "the future may require additional control of direct point sources dischargers" and
that "CMUD may determine in the future that an alternative to surface water discharge
may be more appropriate." These statements strike us as contradictory, i.e., non -point
sources are the main contributor but more control of direct dischargers may be required.
We would like you to clarify this apparent inconsistency and would especially like to
discuss with you further our need to determine future alternatives to surface water
discharge. This discussion likely would be most productive either by telephone or in a
face-to-face meeting.
v Permit Expiration Dates
The permit expiration dates in both permits are incorrect. Pursuant to section 2.b.
of the January 15, 2002 settlement agreement between the Division, South Carolina and
the City of Charlotte, the City has until, at the latest, February 28, 2007, to comply with
the total phosphorous limit of 826 pounds per day on a 12-month rolling average. This is
the limit that applies to the Irwin, Sugar and McAlpine plants. In light of this settlement

provision agreed to by the Division, the Sugar and Irwin permits cannot expire until
February 28, 2007.
1 Description of Treatment Plant — Irwin Creek
The description of the Irwin Creek treatment plant lists four trickling filters.
However, it should be expressly noted in the list that two of these are standby units to be
used when needed.
✓ Description of Treatment Plant — Sugar Creek
The description of the Sugar Creek treatment plant includes trickling filters. The
listing needs to expressly note that these are inactive.
In addition, the RAS pump station description is missing three return pumps.
Maps
The maps in each permit are not correct. It appears that both maps are of the
Irwin Creek facility but we are not sure. We need you to make sure that the correct maps
are included with the correct permits. Please let us know if you need our help with this.
Effluent Limitations and Monitoring Requirements — CBOD, 5-Day
Each permit establishes a limit for CBOD. However, footnote number 2 that
applies to this limit refers to BODS. This should be corrected to reference CBOD5.
J Effluent Limitations and Monitoring Requirements — Cyanide and Mercury
Both permits establish limits for cyanide. The Irwin Creek permit also has an
effluent limit for mercury. In each case, the effluent limits are less than the approved
laboratory detection limit of 10 ug/L for cyanide and 0.2 ug/L for mercury. Furthermore,
although the Division states that it will consider all detections less than these limits "to be
zero for compliance purposes", it still wants Charlotte Mecklenburg Utilities to report all
detected values of these constituents. See footnote 7 to Sugar Creek permit and footnotes
7 and 8 to Irwin Creek permit.
These effluent limits and reporting requirements are not acceptable to Charlotte
Mecklenburg Utilities. The purpose of detection limits is to establish a minimum 90
percent confidence level that an analyte is present at that detected amount. Results
showing concentrations below the detection limit (commonly known as "judgment" or
"J" values) do not satisfy this 90% confidence factor. Such detections may (but do not
always) confirm that an analyte is present but there is no confidence that it is present at
the level indicated.

By these requirements, the Division is requiring Charlotte Mecklenburg Utilities
to report false positives and concentrations as to which there is no statistical satisfaction
of accuracy. The Division cannot require the reporting of such untrustworthy or
inaccurate data. This same provision appeared in the draft permit for McAlpine but was
removed from the final permit based on the objections we have raised here. The same
result should apply to these permits.
V Stream Monitoring Requirements
The stream monitoring frequency requirements are not consistent with the
McAlpine Creek permit and changes made to these requirements in that permit made by
the Division last year. Specifically, the Division agreed last year in a conference call
regarding the draft McAlpine permit that during the June to September time period, the
sampling frequency would be once per week. This provision was included in the final
McAlpine permit. These draft permits provide a sampling frequency of three times per
week. This should be changed to once per week.
Total Phosphorous Limit
There are a number of issues that need to be corrected to make the permits
consistent with the terms of the Settlement Agreement between the Division, South
Carolina and the City. These are as follows:
1. Section 5 of the Settlement Agreement requires the City to notify
SCDHEC and the Division by February 28, 2004 of whether or not it intends to perform
construction activities at either the Sugar Creek or Irwin Creek plants to achieve
compliance with the total phosphorous limit applicable to those plants and the McAlpine
Creek plant. Section 6 of the Settlement Agreement requires that this construction
notification requirement be included as part of the Sugar and Irwin Creek permits. To
comply with the Settlement Agreement, this notification requirement needs to be added
to the permits.
u 2. Pursuant to Section 2.f. of the Settlement Agreement, if the City conducts
construction activities at Sugar Creek to comply with the total phosphorous limit, the
Sugar Creek plant will have an effluent limitation for total phosphorous of 334 pounds
per day averaged on a monthly basis commencing on February 28, 2007. If the City does
not do any construction at Sugar Creek, then there is no such monthly limit. Pursuant to
Section 6 of the Settlement Agreement, these requirements need to be added to the Sugar
Creek permit.
3. Pursuant to Section 2.g. of the Settlement Agreement, if the City conducts
construction activities at Irwin Creek to comply with the total phosphorous limit, the
Irwin Creek plant will have an effluent limitation for total phosphorous of 250 pounds per
day averaged on a monthly basis commencing on February 28, 2007. If the City does not
do any construction at Irwin Creek, then there is no such monthly limit. Pursuant to

Section 6 of the Settlement Agreement, these requirements need to be added to the Irwin
Creek permit.
4. We do not understand why the draft permits include formulas for
calculating annual average mass loading. The applicable standards are mass -based for on
both a monthly and annual basis. It would appear that the definitions for "monthly
average discharge" and "average annual discharge" could be used to determine the per
day discharges as required by the permit. These definitions are found in Part II.A.5.a.
and d. In the alternative, the formulas included in the draft permits could be used
provided that the monthly and annual loadings are divided by, respectively, the number
of days in the month or rolling twelve-month period being measured.
Schedule of Compliance
Part I, Section B of both permits states that the "Permittee shall comply with Final
Effluent Limitations by the effective date of the permit unless specified below." Since
compliance with the phosphorous limitations is not required on the effective date of the
permit, those should be specified in this section.
Part II, Standard Conditions for NPDES Permits
1. The definition of the Division of Water Quality is by the abbreviation
"DEM" or "the Division". DEM refers to the old Division of Environmental
Management. This should be changed to DWQ.
2. Section D.4. states that . approved test methods resulting in the lowest
detection level must be used. We need to discuss with you this requirement with regard
to analyzing for mercury at Irwin Creek. EPA recently approved two new test methods
for analyzing for mercury, methods 1339 and 1631. Method 1339 is a "clean" sampling
method requiring a clean sampling point dedicated only to mercury sampling with
samples collected by a specially trained person wearing protective clothing and using
protective equipment to prevent contamination. Method 1631, an analytical method, is a
new method that we are not aware of any laboratories in North Carolina or elsewhere
being certified to perform. Obviously, as you can discern from these descriptions, both
of these methods are also very expensive to perform.
This section of the permit allows other test procedures to be used if they
are specified in the permit. We would propose adding a footnote to the mercury limit in
the effluent limitations section of the permit specifying that the current method being
used for mercury, EPA Method 245.1 can continue to be used.
3. Part III. C. of the draft permits is entitled "Changes in Discharges of Toxic
Substances." The section, however, deals with toxic pollutants, which is a defined term
in the permits as well as under section 307(a) of the Clean Water Act. Please clarify if
there is a separate defined term for "Toxic Substances" and, if so, what substances are

classified as "Toxic Substances." If there are no such substances, please consider
renaming this section "Changes in Discharges of Toxic Pollutants."
Please check to see if you included the correct Part III in this permit. Part
III.C. seems to be more appropriate for an industrial direct discharger. Furthermore,
these draft permits do not contain the boilerplate language for pretreatment programs that
have been included in Part III of our previous permits.
Notice of EPA and Affected States
Please confirm and provide proof that all required information to be provided to
EPA and any other affected states, most specifically South Carolina, has been provided.
This includes the information requested by EPA for all municipal discharges in the
Catawba River as specified in its letter to Coleen Sullins dated August 2001.
We would very much like to meet or have a conference call with you and other
appropriate members of the Division to discuss the Division's response to these
comments before a final permit is issued. This could very well allow us to avoid
adjudication of the permit and eliminate the need to correct any errors or inaccuracies in
the final permit. Please let me know when you would like to schedule such a call or
meeting.
Sincerely,
4. ratO
cqueline Jarrell
nvironmental Management Division Manager
Enclosures
cc: Barry Gullet (w/encls.)
H. Michael Boyd (w/encls.)
Benue C. Hutson (w/encls.)

j c. (ice. ^-5
HEC
1
PROMOTE PROTECT PROSPER
2600 Bull Street Michael J. Myers
Columbia, SC 29201-1708 NPDES Unit, DWQ
COMMISSIONER:
C. Earl Hunter
BOARD:
Bradford W. Wyche
Chairman
Mark B. Kent
Vice Chairman
Howard L. Brilliant, MD
Secretary
Carl L. Brazell
Louisiana W. Wright
L. Michael Blackmon
Larry R. Chewning, DMD
March 7, 2002
N.C. Dept. of Environment and Natural Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
rq
MAR 1 2 2002
- WATER CL! ;CITY
?U t E BR,tt�^H
•
U
RE: Sugar Creek and Irwin Creek draft permits
NC0024937 and NC0024945
Dear Mr. Myers:
We have reviewed the referenced dated February 13, 2002 and offer these comments
of concern:
1. Without the data from the application (or supplemental data used), we can not
complete a review of the conclusions you have made regarding limits needed (or
not). We request the specific data used in the reasonable potential analysis so that we
can determine if we agree with your conclusions.
2. The NPDES application data requirements appear incomplete. We realize the plan
to utilize DMR data, but this only addresses 11/99 parameters. We request that
DENR consider adding monitoring requirements (e.g., annual) for the balance of the
parameters to collect the data necessary to analyze the need for limits on those
parameters. This would apply to the "second" toxicity test species, also.
3. Fecal coliform limit doesn't appear protective of S.C. Waters, especially since the
waters are impaired. A weekly average of 400/100 ml would not seem to insure that
these discharges don't contribute to the problem. As an alternative, we ask you to
consider either a daily maximum of 400/100 ml or a weekly average of 200/100 ml
to insure compliance with South Carolina standards as noted below:
Not to exceed a geometric mean of 200/100 ml, based on five consecutive
samples during any 30 day period; nor shall more than 10% of the total
samples during any 30 day period exceed 400/100 ml (R.61-68).
4. We don't have enough information to determine if the South Carolina chronic and
acute criteria would be met for ammonia (considering a proposed permit of only a
monthly average requirement). Please provide a basis for having a monthly average
limit only.
5. Please identify the practical quantification limits that govern sampling. Please
address the need to use the new practical quantification limit for mercury of 0.0005
ug/1, using EPA approved methods 1669 and 1631C.
6. How does DENR intend to enforce the phosphorus settlement agreement — as it
relates to compliance deadlines of February 28, 2006 and February 28, 2007, as
applicable — with a permit expiration of June 30, 2005. As well, please identify in
the permits a deadline of February 28, 2004 for notification of DHEC/DENR of the
plans to construct phosphorus removal systems at the Sugar and Irwin Creek
SOUTH CAROLINA DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL

facilities. We did not see a monthly compliance value of 334 lbs/day and 250
lbs/day for the Sugar and Irwin facilities, respectively, as appropriate. Please
address.
7. Please explain the apparent discrepancy between the TRC limits (Sugar has a daily
average requirement and Irwin has a daily maximum requirement). We would
expect a daily maximum for both to comply with acute criteria.
8. We do not have enough information to determine if in fact no limits for copper
and zinc would be appropriate. Moving the in -stream monitoring location is not a
substitute for a definitive conclusion on whether a limit is needed or not. For
example, if South Carolina waters are impaired for copper (CW-013), how can
DENR conclude that a limit for copper is not warranted. Has DENR concluded that
these facilities don't contribute to the impairment? Regarding zinc, has DENR
calculated that there is not "reasonable potential" to violate South Carolina
standards?
9. We are concerned that silver may need to be limited to protect S.C. waters. The
permit notes: "The maximum predicted concentration was greater than the allowable
concentration." We don't have any other information and would like DENR to
provide information that there would be no reasonable potential to impact S.C.
waters.
Please coordinate a response to this with Mike Montebello of my staff (803-898-
4228, [e-mail]). We may have additional comments
based on the information provided (and would like time to respond to you after you
respond to this letter). As well, we would like to see the final permits (complete
copies, including any boiler plate language).
Sincerely,
Je r y P. deBessonet, P.E.
Director, Water Facilities Permitting Division
cc: Mike Montebello
Roosevelt Childress, EPA Water Mgt. Div.

Sugar and Irwin Creek Draft NPDES Permits
14
•
Subject: Sugar and Irwin Creek Draft NPDES Permits
Date: Mon, 28 Jan 2002 15:54:45 -0500
From: Michael Parker <[e-mail]>
Organization: NC DENR - Mooresville Regional Office
To: Mike Myers <[e-mail]>
Mikey,
We have reviewed the drafts and fact sheets for the 2 subject permits
and offer no additional comments (aren't you lucky). Signed copies of
the Fact Sheets are headed back your way in the courier mail.
Now here is a link to find out about liquid siding.
http://www.kryton.net/index ie.html
Enjoy.
Michael Parker - [e-mail]
Environmental Engineer II
North Carolina Dept. of Environment & Natural Resources
Division of Water Quality
919 N. Main Street
Mooresville, NC 28115
Ph: 704.663.1699 Fax: [phone]
DMichael.Parker.vcf
Name: Michael.Parker.vcf
Type: VCard (text/x-vcard)
Encoding: 7bit
Description: Card for Michael Parker
1 of 1
1/29/2002 9:59 AM

Department of Environment and Natural Resources
• . Division of Water Quality
Fact Sheet For NPDES Permit NC0024945
Facility Information
Applicant/Facility Name4:
Applicant Address4:
Facility Address4:
Permitted F1oww:
Type of Wastez.4.7:
Facility/Permit Status4:
CountyZ4•':
Miscellaneous
Receiving Stream2.4:
Stream Classificationt•2:
303(d) Listed?5:
Subbasin2:
Drainage Area (mi2): [calculated]
Summer 7Q10 (cfs)6:
Winter 7Q10 (cfs)6:
Average Flow (cfs)6:
IWC (%):
Primary SIC Code:
Regional Office:
USGS Topo Quad:
Permit Writer:
Date:
Charlotte Mecklenburg Utilities — Irwin Creek
5100 Brookshire Blvd.
4000 Westmont Drive
15.0 MGD (Grade IV — Biological)
Municipal (Domestic and Industrial)
Renewal
Mecklenburg
Irwin Creek
C
Yes — Fecal Coliform, Turbidity
03-08-34
31.0 mi2
4.9 cfs
7.7 cfs
43.0 cfs
83%
4952
Mooresville
Charlotte West (G 15 NW)
Michael Myers
November 5, 2001
Summary
Charlotte Mecklenburg Utilities (CMUD) owns and operates five facilities in and around the
Mecklenburg County area, including the Irwin Creek facility. Irwin Creek WWTP is located in the
Southwestern portion of Mecklenburg County and currently has an NPDES permit to discharge up to
15.0 MGD of treated municipal wastewater through one of two outfalls (001 and 002). CMUD submitted
an application for renewal of this NPDES permit on March 2, 2001 (183 days prior to expiration). The
NPDES Unit has reviewed the application, correspondence files, discharge monitoring reports, permit
files, instream data and other pertinent data in developing this permit. This fact sheet summarizes the
rationale used to determine permit limits and conditions.
Wastewater is treated at the Irwin Creek WWTP, using a 15.0 MGD trickling filter/extended air plant
comprised of the following treatment units:
• Mechanical bar screen
• Influent pump station
• Grit removal
• Flow equalization
• Influent flow measurement
• Three primary clarifiers
Fact Sheet
NPDES Renewal
Page 1

2
• Four trickling filters
• pH adjustment (NaOH)
• Eleven aeration basins (diffused air)
• Three secondary clarifiers
• Chlorine gas disinfection
• Sodium bisulfite dechlorination
• Ten tertiary filters
• Effluent flow measurement
• Cascade aeration
• Four anaerobic digesters
• 300,000 gallon sludge storage
• Two gravity belt thickeners with polymer feed
• 1.8 MG digested sludge storage tank
After treatment, wastewater is discharged into Irwin Creek, which is a class C stream in the Catawba
River Basin. Sludge is stabilized anaerobically, then land applied according to DWQ permit WQ000057.
The last wasteload allocation was conducted in 1996. Since that time, there have been no changes that
would dictate a reevaluation of the wasteload allocation, except as related to nutrients which will be
discussed later. The 7Q10 stream flow at the point of discharge is 4.9 cfs. The average and 30Q2 stream
flows at this point are 43 cfs and 9.9 cfs, respectively.
The 1998 permit incorporates water quality based limits for carbonaceous biochemical oxygen demand,
ammonia, dissolved oxygen, fecal coliform, total residual chlorine, cadmium, chromium, cyanide, lead
and mercury.
Pretreatment
The Irwin Creek facility serves a population of 46,515 in the Charlotte area and accepts a permitted
monthly industrial flow of 1.996 MGD and maintains an approved pretreatment program. The
pretreatment program has 28 permitted Significant Industrial Users, as summarized in Table 1.
Table 1. Significant Industrial Users for the CMUD — Irwin Creek WWTP
Significant Industrial User
IUP
Number'
40 CFR Type Text
Permitted Flow
Allied Zinc Finishing, Inc.
1012
Metal Finisher
0.013
ARAMARK Uniform Services, Inc.
0060
Ind. Laundry
0.1
BASF Corporation
633
OCPSF
0.15
Carolina Foods, Inc.
1003
Food
0.015
Carolina Foods, Inc.
1003
Food
0.025
Charlotte Pipe & Foundry, Co.
0665
Foundry
0.55
IFCO ICS-North Carolina, Inc.
(formerly PalEx Container)
0284
Drum Reconditioning
0.015
Chematron Inc.
1002
Textile Chem.
0.018
Chesapeake Treatment Company, LLC
1007
WWTP for Coca-Cola
Company
0.55
Canteen Vending Services
118
Food
0.033
Chemcentral Charlotte
1005
Chem. Repkg
0.01
Pan-Glo Charlotte
121
Reglazer
0.026
Fleet Operations, Inc.
dba The Charlotte Tank Wash
1009 .
Tank Wash
0.009
Fleming Laboratories Inc.
0183
Pharmaceutical
0.012
Heritage Environmental Services, LLC
1001
CWT
0.019
Fact Sheet
NPDES Renewal
Page 2

Independent Beverage Co.
0117
Food
0.11
Interstate Brands Corporation,
Merita Division
684
Food
0.062
Krispy Kreme
0101
Food
0.015
Piedmont Heat Treating Corp.
157
metals -Heat Treating
0.01
Pneumafil Metal Products
Division of Beacon Industrial Group
0366
Metal Finisher
0.018
Qualex, Inc.
0360
Photo lab with Ag
recovery
0.1
Southern Aluminum Finishing
571
Metal Finishing
0.012
Stork Screens America, Inc.
675
Metal Finisher
0.05
Textilease Corporation
0029
Industrial Laundry
0.15
Trane Charlotte
0125
Metal Finisher
0.015
Weyerhaeuser Paper Co.
145
Paper Board
0.017
Fuel Systems LLC (formerly Borg
Warner)
1010
metals -metal fin
0.02
Ecosolve, LLC
1013
Food
0.008
US Airways - Maintenance Facility
1014
Aircraft Maintenance
0.015
US Airways - Maintenance Facility
1014
Aircraft Maintenance
0.015
1. IUP — Industrial User Permit
Discharge Monitoring Report Data Review
According to the self -monitoring data, the facility is achieving ammonia removal through nitrification
(See Figure 1). Though the system is not designed for denitrification or phosphorus removal the system
is achieving some measure of both as evident from the self -monitoring data (See Figures 2 and 3). Total
phosphorus and total nitrogen averaged 2.09 mg/L and 17.9 mg/L, respectively in the effluent for the year
2001, which is consistent with the 2000 averages (average TN —16.932 mg/L and average TP — 2.17 mg/L).
Residual chlorine levels are typically within the range expected for a facility practicing dechlorination,
with an average of 0.975 µg/L, 6.382 µg/L, and 0.159 µg/L for 2001, 2000 and 1999, respectively. The
annual average flows averaged 70.4%, 65.2%, and 69.0% of the 15.0 MGD permitted flow for 2001, 2000
and 1999, respectively.
Figure 1. Influent and Effluent Ammonia Concentrations for the CMUD — Irwin Creek WWTP.
35.00
30.00
2500
a 20.00
z
2 15.00
10.00
5.00
0.00
�1
4
I,
0
50 100 150
200 250 300
- lament
— EMOuent
Sample
Fact Sheet
NPDES Renewal
Page 3

Figure 2. 2000 Influent and Effluent Total Nitrogen Loadings for the CMUD - Irwin Creek WWTP.
35.00
30.00
25.00
20.00
:7
a
E
z
E-
15.00
10.00
5.00
0.00
0
1
2
3 4 5
Sample
6
7
8
9
10
— Influent
— Effluent
Figure 3. 2000 Influent and Effluent Total Phosphorus for the CMUD - Irwin Creek WWTP.
8.00
7.00
6.00
5.00
i
E 4.00
3.00
2.00
1.00
0.00
0
2 4 6 8
Sample
10
12 14
— Influent
_.__ Effluent
Fact Sheet
NPDES Renewal
Page 4

Current Stream Conditions
Irwin Creek flows in to Sugar Creek, which eventually flows to the Catawba River in South Carolina.
Though Sugar and Irwin Creeks are not within the Lake Wylie drainage area, they are within the Lake
Wateree Watershed.
Irwin Creek is classified as a C water in the Catawba River Basin (North Carolina's classification system).
Irwin Creek discharges into Sugar Creek, which is also classified as a C water for the North Carolina
segment of the stream. Upon crossing in to South Carolina, Sugar Creek changes classified to FW water
(South Carolina's classification system), which means it is designated for primary and secondary
recreation and water supply, as well as fishing and survival and propagation of a balanced and
indigenous aquatic community of flora and fauna.
In terms of individually permitted NPDES facilities, the Irwin Creek watershed receives the discharge
from three dischargers, with the CMUD - Irwin Creek WWTP the largest. The Irwin Creek Watershed is
an extremely urbanized watershed draining the City of Charlotte, as can be seen in Figure 4 below.
Based on DWQ sampling, the benthic community improved from 1992 to 1997 from 'poor' to 'fair'.
Though improvement was noted, a 'fair' rating is indicative of an impaired stream. Similarly, the fish
community while showing impacts did see improvement from 1993 to 1997. Though the fish community
remains 'poor', there were twice as many fish collected in 1997 as were collected in 1993 and a greater
percentage of multiple age groups were represented.
Figure 4. Sugar Creek Watershed
CHARLOTTE D
ONARCH; INC. "'
USINS REAL ESTATE/GAT: AY VL
ERS SUPPLY CO.INC
CMUD - Irwin Creek]
DUSTRIAL FIRE PROTECTION
Fact Sheet
NPDES Renewal
Page 5

Irwin Creek is listed as an impaired water according to North Carolina's draft 2000 303(d) list. The
problem parameters are identified as fecal coliform, turbidity and poor to fair biological communities.
Possible sources for the impairment are non -point source urban runoff, and point sources. According the
Mooresville Regional Office, turbidity may be due to sampling during and directly after rainfall events.
Possible sources for the impairment include urban runoff, non -urban development, and municipal point
sources.
Downstream of the discharge, Sugar Creek is impaired in South Carolina and North Carolina for fecal
coliform and impaired biological community. In South Carolina, the stream has improved from 'not
supporting' to 'partially supporting' between the 1993 to 1998 sampling events.
Nutrients
As stated, Irwin Creek is within the Lake Wateree watershed. According South Carolina's Department of
Health and Environmental Control, Lake Wateree and Fishing Creek Reservoir both exhibit a trophic
status of category I, which is indicative of the highest level of euthrophication. The Division is currently
working with the State of South Carolina and CMUD on nutrient control for the McAlpine Creek WWTP,
Sugar Creek WWTP and the Irwin Creek WWTP. It is anticipated a management strategy for total
phosphorus will be agreed upon and incorporated into the NPDES permits for the three referenced
facilities.
Instream Monitoring
CMUD conducts extensive monitoring of Irwin Creek, Little Sugar Creek and McAlpine Creek. Irwin
Creek is monitored upstream of the WWTP and downstream at five Sugar Creek sites. Analysis of the
instream data shows no violations of North Carolina's dissolved oxygen standard. Copper and zinc data
indicate that the normal Division assumption of zero background is inappropriate for these parameters.
Both of these parameters are action level parameters in North Carolina, so alternative background
concentrations were not calculated, since they would have no impact on the conclusions reached from the
reasonable potential analysis.
Though copper and zinc are 'action level' parameters in North Carolina, South Carolina has adopted
acute and chronic standards for both copper and zinc. The acute/chronic standards adopted by South
Carolina are 3.8/2.9 µg/L for copper and 37/37 µg/L for zinc. Copper and Zinc are monitored in Sugar
Creek at Yorkmont Road. Monitoring at this location indicates significant copper and zinc
concentrations. Since this monitoring station is located several miles from the NC/SC State line this data
does not allow for conclusions regarding compliance with South Carolina's standards for copper and
zinc. Therefore, it is recommended that copper and zinc monitoring move from station SC1 to SC4 in
Sugar Creek and from LSC2 to LSC3 in Little Sugar Creek.
Additionally, South Carolina's 2000 305(b) report list the monitoring station at CW-013 as 'not
supporting' with an identified cause of chromium and copper. The source of these metals was not
identified it is recommended that in addition to copper and zinc monitoring at station SC4 that chromium
monitoring be added to the instream monitoring program at station IC1, SC4, LSC1, LSC3, MC1 and
MC2.
Currently, CMUD monitors cadmium at stations MC1 and MC2. A review of data from January 1997
through October 2001, resulted in no detectable quantities of cadmium over the period of review. Since
cadmium is not identified as a potential source of impairment, it is recommended that instream cadmium
monitoring be removed from the instream monitoring program.
Compliance Summary:
Fact Sheet
NPDES Renewal
Page 6

Staff Reports indicate that the facility is well maintained and operated.
Irwin Creek WWTP has a very good compliance record. Over the past three years, the facility had no
violations of monthly average limits in 2001, one violation of monthly average limits in 2000 (BOD) and
three violations of monthly average limits in 1999 (BOD, TSS and fecal coliform).
Toxicity Testing
Current Requirement: Chronic toxicity limit monitored quarterly @ 83%.
The facility has a good toxicity compliance record over the past four years. The facility did fail one
toxicity test in July 2000, but followed up the subsequent twomonths with passes.
Recommended Requirement: Chronic toxicity limit monitored quarterly @ 83%.
Toxicant Analysis
Using the self monitoring data required per the NPDES permit and the approved Long Term Monitoring
Plan, reasonable potential analysis' were conducted on the following toxicants: arsenic, cadmium,
cyanide, chromium, copper, lead, mercury, nickel, silver, selenium and zinc. The standards used for the
analysis are consistent with the standards for a class C stream.
Refer to the reasonable potential analysis to view the data sets and results.
Arsenic — Analysis indicated that the maximum predicted concentration is less than the allowable
concentration. There will be no limit or monitoring requirement for this parameter in the NPDES permit.
Monitoring for this parameter will continue as part of the Long Term Monitoring Plan required as part of
the approved pretreatment program.
Cadmium — Analysis indicated that the maximum predicted concentration is less than the allowable
concentration. There will be no limit or monitoring requirement for this parameter in the NPDES permit.
Monitoring for this parameter will continue as part of the Long Term Monitoring Plan required as part of
the approved pretreatment program.
Cyanide — The analysis indicated that the maximum predicted concentration is greater than the allowable
concentration. Therefore the limit shall remain in the permit. If the facility the facility continues to not
detect cyanide in their effluent through February 2002, CMUD may request removal of the limit.
Chromium — Analysis indicated that the maximum predicted concentration is less than the allowable
concentration. Though reasonable potential analysis indicates no reasonable potential chromium,
monitoring will remain as a condition, since South Carolina has listed a portion of Sugar Creek as 'not
supporting' for chromium. No limit is proposed for this facility, since based on discharge monitoring
report data, the Irwin Creek Wastewater treatment plant is not a likely source of chromium.
Copper — The maximum predicted concentration was greater than the allowable concentration. However,
copper is a action level parameter and no standard exist. It is the Division's position that a limit is not
appropriate for an action level parameter unless the facility has demonstrated toxicity problems. Since
the facility has a good toxicity compliance record no limit will be incorporated into the permit; however,
monitoring shall remain as a condition.
Lead - Analysis indicated that the maximum predicted concentration is less than the allowable
concentration. There will be no limit or monitoring requirement for this parameter in the NPDES permit.
Monitoring for this parameter will continue as part of the Long Term Monitoring Plan required as part of
the approved pretreatment program.
Fact Sheet
NPDES Renewal
Page 7

Mercury — The facility has had no detectable mercury concentration greater than 0.2 µg/L since December
2000. Therefore, no limit or monitoring shall be required as a condition for the permit. Monitoring for this
parameter will continue as part of the Long Term Monitoring Plan required as part of the approved
pretreatment program.
Nickel — The maximum predicted concentration was greater than the allowable concentration. Therefore,
a weekly average limit of 106.5 µg/L and a daily maximum limit of 261 µg/L will be implemented into the
NPDES permit.
Selenium — Analysis indicated that the maximum predicted concentration is less than the allowable
concentration. There will be no limit or monitoring requirement for this parameter in the NPDES permit.
Monitoring for this parameter will continue as part of the Long Term Monitoring Plan required as part of
the approved pretreatment program.
Silver - The maximum predicted concentration was greater than the allowable concentration. However,
silver is a action level parameter and no standard exist in North Carolina. It is the Division's position that
a limit is not appropriate for an action level parameter unless the facility has demonstrated toxicity
problems. Since the facility has a good toxicity compliance record no limit will be incorporated into the
permit; however, monitoring shall remain as a condition.
Zinc - The maximum predicted concentration was greater than the allowable concentration. However,
zinc is an action level parameter and no standard exists in North Carolina. It is the Division's position
that a limit is not appropriate for an action level parameter unless the facility has demonstrated toxicity
problems. Therefore, the monitoring requirement shall remain as a condition for the permit.
PROPOSED WATER QUALITY BASED LIMITS
This permit contains water quality based limits for carbonaceous biochemical oxygen demand, ammonia,
dissolved oxygen, fecal coliform, total residual chlorine, total phosphorus, cyanide, mercury, nickel and
toxicity.
PROPOSED TECHNOLOGY BASED LIMITS
This permit contains technology based limits for pH and percent removal for carbonaceous biochemical
oxygen demand and total suspended solids.
ADMINISTRATIVE PROCEDURES
15A NCAC 02H .0109 PUBLIC NOTICE
(a) Notice of Application
(1) Public notice of each complete individual NPDES permit application and each general NPDES
permit shall be circulated in the geographical areas of the proposed discharge by the Director at
least 45 days prior to any proposed final action:
(A) by publishing the notice one time in a newspaper having general circulation in said
county; and
(B) by mailing the notice to all persons or agencies listed in Subsection (c) of this Rule.
(2) The notice shall set forth at least the following:
(A) name, address, and phone number of the agency issuing the public notice;
(B) name and address of each applicant;
(C) brief description of each applicant's activities or operations which result in the
discharge
described in the NPDES application;
(D) name of waterway to which each discharge is made and a short description of the
location of each discharge on the waterway indicating whether such discharge is a new
' Fact Sheet
NPDES Renewal
Page 8

or an existing discharge;
(E) a statement of the tentative determination to issue or deny an NPDES permit for the
discharge described in the NPDES application;
(F) a brief description of the procedures for the formulation of final determinations,
including a 30-day comment period and any other means by which interested persons
may influence or
comment upon the determinations; and
(G) address and phone number of state agency premises at which interested persons may
obtain further information, request a copy of the draft permit, request a copy of the fact
sheet, and inspect and copy NPDES application forms and related documents. Copies of
the fact sheet shall be made available free upon request. Copies of the information on file,
other than fact sheets, will be made available upon request and payment of the cost of
reproduction.
(3) Public notice for those activities covered by Certificates of Coverage issued pursuant to a
general permit and Authorizations to Construct shall not be required.
(b) Notice of Public Meeting
(1) Notice of public meeting on any NPDES permit application shall be circulated in the
geographical areas of the proposed discharge by the Director at least 30 days prior to the date of
the meeting:
(A) by publishing the notice one time in a newspaper having general circulation in said
county;
(B) by mailing the notice to all persons and government agencies which received a copy
of the notice or the fact sheet for the NPDES application; and
(C) by mailing the notice to any person or group upon request.
(2) The notice of any public meeting shall include at least the following:
(A) name, address, and phone number of agency holding the public meeting;
(B) name and address of each applicant whose application will be considered at the
meeting;
(C) name of waterway to which each discharge is made and a short description of the
location of each discharge on the waterway;
(D) a brief reference to the public notice issued for each NPDES application including
identification number and date of issuance;
(E) information regarding the time and location for the meeting;
(F) the purpose of the meeting;
(G) address and phone number of premises at which interested persons may obtain
further information, request a copy of each draft NPDES permit, request a copy of
each fact sheet, and inspect and copy NPDES forms and related documents; and
(H) a brief description of the nature of the meeting including the rules and
procedures to be followed; The notice shall also state that additional information is
on file with the Division of Environmental Management, Department of
Environment, Health, and Natural Resources at the Archdale Building at 512 North
Salisbury Street, Raleigh, North Carolina, and may be inspected at any time during
normal working hours. Copies of the information on file will be made available upon
request and payment of cost of reproduction.
(c) Mailing Lists. Any person may request to receive copies of all notices required under this Rule and
the Director shall mail such notice to any such person. An annual charge of twenty-five dollars ($25.00)
may be charged for any person desiring to be placed and maintained on the NPDES Permit mailing list.
The Director shall also give notice to the following for NPDES permits:
Fact Sheet
NPDES Renewal
Page 9

•
(1) State water pollution control agency for the States of Virginia, South Carolina, Tennessee, and
Georgia;
(2) Appropriate district engineer, U.S. Army Corps of Engineers;
(3) Lead agency responsible for preparation of plan pursuant to Section 208(b) of the Clean Water
Act, 33 U.S.C. Section 1251 et seq, in approved 208 areas;
(4) State agency responsible for the preparation of plans pursuant to Section 303(e) of the Clean
Water Act, 33 U.S.C. Section 1251 et seq;
(5) North Carolina Department of Environment, Health, and Natural Resources, Division of
Environmental Health; and
(6) Any other federal, state, or local agency upon request.
History Note: Authority G.S. 143-215.1(a)(1); 143-215.1(c); 143-215.4(a); 143-215.4(c); Eff. February 1, 1976;
Amended Eff. March 1, 1993; August 1, 1988; October 1, 1987; December 1, 1984.
15A NCAC 02H .0111 MEETINGS AND HEARINGS
(a) Public Meetings:
(1) The Director shall provide an opportunity for the applicant, any affected state, any affected
interstate agency, the regional administrator, or any interested agency, person, or group of
persons to request or petition for a public meeting with respect to NPDES permit applications.
Any person who desires a public meeting on any NPDES permit application shall so request in
writing to the Director within 30 days following the publication date of the notice of application.
Any such request or petition for public meeting shall indicate the interest of the party filing such
request and the reasons why a meeting is warranted.
(2) The Director is delegated authority to determine if a public meeting shall be held in
accordance with G.S. 143-215.1(c)(3) and to issue public notice and conduct such meeting for the
Commission.
(3) All comments received within 30 days following the publication date of the notice of NPDES
permit application shall be made part of the application file and shall be considered by the
Director prior to taking final action on the application.
(4) Any meeting brought pursuant to this Subsection shall be held in the geographical area of the
proposed discharge or other appropriate area, in the discretion of the Director, and may, as
appropriate, consider related groups of permit applications.
(b) Adjudicatory Hearings and appeals shall be conducted in accordance with Article 3 of Chapter 150B
of the General Statutes.
History Note: Authority G.S. 143-215.3(a)(1); 143-215.1(c)(1); 143-215.3(a)(3); 143-215.3(a)(4); 143-215.5;
143-215.1(e); Eff. February 1, 1976;
Amended Eff. March 1, 1993; November 1,1987.
15A NCAC 02H .0112 FINAL ACTION ON PERMIT APPLICATIONS
(a) The Director shall take final action on all NPDES applications not later than 60 days following notice
of intent to issue or deny, or, if a public meeting is held, within 90 days following the closing of the
record of the meeting or in the case of an Authorization to Construct permit 90 days after the receipt of a
complete application or, if a public meeting is held concerning the Authorization to Construct, within 90
days following the closing of the record of the meeting.
(b) The Director is authorized to:
(1) issue a permit containing such conditions as are necessary to effectuate the purposes of G.S.
143-215.1 and G.S. 143-215.67;
Fact Sheet
NPDES Renewal
Page 10

(2) issue a permit containing time schedules for achieving compliance with applicable effluent
standards and limitations, water quality standards, and other legally applicable requirements;
(3) modify or revoke any permit upon giving 60 days notice to the person affected pursuant to
Rule .0114(a) of this Section;
(4) suspend a permit pursuant to Rule .0114(a) of this Section;
(5) rescind a permit upon request by the permittee;
(6) deny a permit application:
(A) where necessary to effectuate the purposes of Article 21 Chapter 143,
(B) for a discharge prohibited by G.S. 143-214.2(a),
(C) where the Secretary of the Army finds the discharge would substantially impair
anchorage and navigation,
(D) for a discharge to which the regional administrator of EPA has objected as
provided in Section 402(d) of the Clean Water Act as amended, 33 U.S.C. Section
1251 et seq,
(E) for any point discharge which conflicts with a plan approved pursuant to Section
208(b) of the Clean Water Act as amended, 33 U.S.C. Section 1251 et seq, effective
February 4, 1987.
(c) The permit applicant has the burden of providing sufficient evidence to reasonably ensure that the
proposed system will comply with all applicable water quality standards and requirements. No permit
may be issued when the imposition of conditions cannot reasonably ensure compliance with applicable
water quality standards and regulations of all affected states.
(d) Permits shall be issued or renewed for a period of time deemed reasonable by the Director except in
no case shall permits be issued for a period to exceed five years.
History Note: Authority G.S. 143-215.3(a)(1); 143-215.1(c)(4); 143-215.1(b); 143-215.3(a)(3); 143-215.3(a)(4);
143-215.1(c)(5); 143-214.2(a); 143-215; 143-215.2(a); Eff. February 1, 1976;
Amended Eff. March 1, 1993; October 1, 1987; September 1, 1986; December 1,1984.
Proposed Changes
Cadmium limit and monitoring has been deleted from the permit.
Chromium monitoring has been added as a condition for the permit.
Cyanide limit and monitoring requirement has been footnoted to allow the facility to request removal of
cyanide limit and monitoring if the facility continues to not detect cyanide in its effluent through 2002.
Lead limit and monitoring requirement has been deleted from the permit.
Mercury limit and monitoring has been deleted from the permit.
A weekly average and daily maximum nickel limit and monitoring requirement has been added as a
condition for the permit.
Move instream copper and zinc monitoring in Sugar Creek from SC1 to SC4
Move instream copper and zinc monitoring in Little Sugar Creek from LSC2 to LSC3.
Instream chromium monitoring has been added to the permit.
Delete instream cadmium monitoring.
The conditions for total phosphorus have been modified in accordance with the agreement reached
between North and South Carolina.
Fact Sheet
NPDES Renewal
Page 11

Proposed Schedule for Permit Issuance
Draft Permit to Public Notice:
Permit Scheduled to Issue:
References
1. Division of Water Quality's Basinwide Information Management System, December 21, 2001,
http://h2o.enr.state.nc.us/bims/reports/basinsandwaterbodies/alpha/Neuse.pdf
2. 1999. NPDES Regional Staff Report and Recommendations for the Renewal of the CMUD — Irwin
Creek WWTP, August 12, 1999, Asheville Regional Office
3. 1999. Catawba River Basinwide Water Ouality Plan. North Carolina Division of Water Quality,
Water Quality Section.
4. 2001. NPDES Permit Application Standard Form A, Charlotte -Mecklenburg Utilities Department
— Irwin Creek WWTP.
5. 2000. 303(d) List of North Carolina Impaired Waters - Draft. North Carolina Division of Water
Quality, Water Quality Section. Copies obtained through Planning Branch, Archdale Building,
512 N. Salisbury St., Raleigh, North Carolina.
6. 1993. Low Flow Characteristics of Streams in North Carolina, United States Geological Survey
Water -Supply Paper 2403. Copies obtained at U.S. Geological Survey, Map Distribution, Box
25286, MS306, Federal Center, Denver, CO 80225.
7. 1998. NC0024945 NPDES Permit. Issued to CMUD- Irwin Creek. Copies obtained through The
Division of Water Quality, Central Files, Archdale Building, 512 N. Salisbury St., Raleigh, North
Carolina.
Fact Sheet
NPDES Renewal
Page 12

State Contact
If you have any questions on any of the above information or on the attached permit, please contact
Michael Myers at [phone] ext. 508.
NAME: i�!i C.u./ c, DATE: / ? / , z
NPDES SUPERVISOR
NAME: DATE:
Fact Sheet
NPDES Renewal
Page 13

Regional Office Comment
acat-.6v(9-e,
NAME: '---le
DATE:
2i-07
Fact Sheet
NPDES Renewal
Page l3

Facility Name =
Ow (MGD) =
WWTP Classification
NPDES # =
Receiving Stream
IWC (%) =
Final Results:
CMUD - Irwin Creek
15
4
NC0024945
Irwin 'Creek
82.59
Reasonable Potential Summary
Stream Classification
7Q10s (cfs)=
30Q2 (cfs)
Qavg (cfs)
to
2°
30
4°
C
4.9.
43
Arsenic
Max. Pred Cw
Allowable Cw
2.9 µg/1
60.5 µg/1
Implementation
!Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
1
!Monitoring
'Frequency None
Aluminum
Max. Pred Cw
Allowable Cw
Not a POC µg/l
105.3 µg/1
Ilmplementation
'Are all reported values less than?
!Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
!Frequency None
Barium
Max. Pred Cw
Allowable Cw
Not a POC µg/I
Not a POC µg/I
'Implementation
'Are all reported values less than?
Its the detection limit acceptable?
Yes
Yes `
Limit?
Monitor?
No
No
I
j Monitoring
I Frequency None
Benzene
Max. Pred Cw
Allowable Cw
Not a POC µg/l
73.3 µg/1
,Implementation
'Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
,
I Monitoring
iFrequency None
Beryllium
Max. Pred Cw
Allowable Cw
Not a POC µg/l
2.0 µg/l
:Implementation
,Are all reported values less than?
!Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
(Frequency None
Carbon Tetrachloride
Max. Pred Cw
Allowable Cw
Not a POC µg/I
6.27 µg/l
'Implementation
'Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes_
Limit?
Monitor?
No
No
I
jMonitoring
'Frequency None
Cadmium
Max. Pred Cw
Allowable Cw
1.2 µg/I
2.4 µg/l
!Implementation
(Are all reported values less than?
Its the detection limit acceptable?
No
Yes ' `
Limit?
Monitor?
No
No
1
I Monitoring
i Frequency None
i
1
1/2 FAV (non Trout)
15.0
µg/l
'
1/2 FAV (Trout)
21
µg/1
1/2 FAV
42
µg/1
I
Chloride
Max. Pred Cw
Allowable Cw
Not a POC mg/L
278.5 mg/L
'Implementation
'Are all reported values less than?
,Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
' Frequency None
Chlorinated Benzenes
Max. Pred Cw
Allowable Cw
Not a POC µg/l
Not a POC µg/1
!Implementation
lAre all reported values less than?
Its the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
Frequency None
Chloroform
Max. Pred Cw
Allowable Cw
Not a POC µg/l
Not aPOC µg/l
'Implementation
!Are all reported values less than?
lIs the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
!Monitoring
1 Frequency None

Facility Name =
Ow (MGD) =
IWC (%) =
NPDES # =
Receiving Stream
Final Results:
7 ,c, ..:••- ,,, k li • . .. •i:4,:f,..,.; gp.59 5,1Er.,L(,:c42'...
rt.i,I,..,,,:;t•li, • , :k,,,?,,, ,:,,,,1,.. , 'Malidir:,:':f:•;g:IPVp4t1
Eft:Li,!:V3ET::, IPA ,,,, id:. -:..:, WITSgg. 1":1.111liddigilitifiRgttd
17,7) -.' 441;:j:,•5011Dif litc'':€121IrTatKOWS.• ''. ' I,Bni
Reasonable Potential Summary
Stream Classification
7QI Os (cfs)=
30Q2 (cfs)
Qavg (cfs)
1 0
2°
3 0
4°
frg!-F44‘,--T-11,74,1
• 'IL,
WON
•
Chromium
Max. Pred Cw 36.8 µg/I
Allowable Cw 60.5 µg/1
:Implementation
I
,Are all reported values less than?
!Is the detection limit acceptable?
No
Yes
Limit?
Monitor?
No
No
1
I
!Monitoring
!Frequency None
I
1/2 FAV
1022114/1
I
Copper
Max. Pred Cw 62.3 Awl
Allowable Cw 8.5 pg/l
i Implementation
'Are all reported values less than?
!Is the detection limit acceptable?
No
Yes
Limit?
Monitor?
No
Yes
i .
I
'Monitoring
! Frequency 2/Month
I
I
1/2 FAV
7.3
41
I
1/2 FAV
5.8
µg/1
i
Cyanide
Max. Pred Cw 12.8 pg/l
Allowable Cw 6.1 µg/1
'Implementation
,Are all reported values less than?
the detection limit acceptable?
No
Yes
Limit?
Monitor?
Yes
Yes
'
!Monitoring
I Frequency Weekly
I
1
1/2 FAV
22.0
µg/1
!Is
1
1/2 FAV
1.0
gg/1
;
Dioxin
Max. Pred Cw Not a POC pg/l
Allowable Cw 15.9 pg/I
1
'Implementation
!Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
!Monitoring
'Frequency None
Flouride
Max. Pred Cw Not a POC µg/I
Allowable Cw 2179.4 µg/I
:Implementation
I
,Are all reported values less than?
!Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
1
I
I Monitoring
! Frequency None
Hexachlorobutadiene
Max. Pred Cw Not a POC µg/1
Allowable Cw 51.6 µg/1
'Implementation
iAre all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
i Monitoring
'Frequency None
Iron
Max. Pred Cw Not a POC pg/l
Allowable Cw 1.2 µg/I
i ,Implementation
!Are all reported values less than?
ifs the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
1
!Monitoring
;Frequency None
Lead
Max. Pred Cw 12.4 µg/1
Allowable Cw 30.3 pg/l
:Implementation
I
,Are all reported values less than?
!Is the detection limit acceptable?
No
Yes
Limit?
Monitor?
No
No
:
I
,Monitoring
I Frequency None
1/2 Fav
33.8
pg/1
I
1/2 FAV
221.0
µg/1
:
Manganese
Max. Pred Cw Not a POC go
Allowable Cw Not a POC µg/1
1
'Implementation
!Are all reported values less than?
Its the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
.
!Monitoring
'Frequency None

Facility Name
Ow (MGD)
1 WC (%)
NPDES #
Receiving Stream
Final Results:
f t ,� �, Cj�{D#' , r� Iiiie � c
4i . , t� .!._'ki - tiFf+i:.•�SJ r3° �[w •.'',2,.;Mk[ 4'I
✓ pfy
:.. N6 �" A+�i6yi Sit'.....,,.
..ii..r .....,r».i v.
�y; 3
ik�l wbi_�� e�.: �ta. .....�....nr.i ��i_tular.�
.i...J.-.4x.A-.
S�.
'y ,-i
11NC., �.9;
3
lia ., t,3
� s�ia ` :Aass,r.
e- : or
"[:�-3"F'l t:a
Reasonable Potential Summary
Stream Classification
7Q1Os (cfs)=
30Q2 (cfs)
Qavg (cfs)
1° 2° 30 4°
is r S.ni
yi
T Q� ' .tom,
MBAS
Max. Pred Cw Not a POC µg/1
Allowable Cw 605.4 µg/I
:Implementation
'Are all reported values less than?
!Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
i
' Monitoring
! Frequency None
Mercury
Max. Pred Cw 0.3523 µg/1
Allowable Cw 0.0145 µg/1
'Implementation
:Are all reported values less than?
'Is the detection limit acceptable?
No
Yes
Limit?
Monitor?
Yes
Yes
I
j Monitoring
'Frequency Weekly
Nickel
Max. Pred Cw 317.7 µg/1
Allowable Cw 106.5 µg/1
!Implementation
'Are all reported values less than?
jIs the detection limit acceptable?
Yes
Yes ''
Limit?
Monitor?
Yes
Yes
I
'Monitoring
jFrequency Weekly
'
I
1/2 FAV
261.0
mil
'
1/2 FAV
75.0
µg/1
!
Oil & Grease
Max. Pred Cw Not a POC mg/L
Allowable Cw 36.3 mg/L
(Implementation
'Are all reported values less than?
the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
1
1
!Monitoring
Frequency None
PCB
Max. Pred Cw Not a POC µg/I
Allowable Cw 0.2122 mil
iIs
'Implementation
'Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
;
'
!Monitoring
'Frequency None
Phenol
Max. Pred Cw Not a POC µg/l
Allowable Cw 0.0000 µg/1
:Implementation
'Are all reported values less than?
!Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
:
'Monitoring
!Frequency None
Silver
Max. Pred Cw 5.7 µg/I
Allowable Cw 0.1 µg/1
'Implementation
'Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
i Monitoring
'Frequency None
I
1/2 FAV
1.2
µg/1
1/2 FAV
1.9
µg/l
I
Selenium
Max. Pred Cw 2.9 µg/1
Allowable Cw 6.1 µg/1
Implementation
'Are all reported values less than?
,Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
,Frequency None
Tetrachloroethane
Max Pred. Cw Not a POC µg/t
Allowable Cw 12.65 µg/1
!Implementation
'Are all reported values less than?
jls the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
I
'Monitoring
:Frequency None
Tetrachloroethylene
Max Pred. Cw Not a POC µg/1
Allowable Cw Not a POC µg/I
'Implementation
!Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
_
'
!Monitoring
'Frequency None
Total Dissolved Solids
lmmplementation
l

Max Pred. Cw
Allowable Cw
Not a POC mg/L !Are all reported values Tess than?
Not a POC mg/L !Is the detection limit acceptable?
Yes Limit? No (Monitoring
Yes Monitor? No !Frequency None
Facility Name =
Ow (MGD) =
/IVC (%) =
NPDES # --
Receiving Stream
Final Results:
CMUD - Irwin Creek
15
82.59
N C0024945
Irwin Creek
Reasonable Potential Summary
Stream Classification
7QIOs (cfs)=
30Q2 (cfs)
Qavg (cfs)
C
(I
0
0
4.9
9.9
43
J
Toluene
Max. Pred Cw
Allowable Cw
Not a POC µg/l
9.1 µg/1
'Implementation
:Are all reported values less than?
'Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
� Monitoring
' Frequency
None
Triaklyltin
Max. Pred Cw
Allowable Cw
Not a POC µg/1
0.0 µg/1
!Implementation
lAre all reported values less than?
;Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
i
I Monitoring
Frequency
None
Trichloroethylene
Max. Pred Cw
Allowable Cw
Not a POC µg/1
94.3 µg/1
'Implementation
1Are all reported values less than?
Its the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
'
, Monitoring
'Frequency
None
Turbidity
Max. Pred Cw
Allowable Cw
Not a POC NTU
60.5 NTU
'Implementation
:Are all reported values less than?
Its the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
i Monitoring
Frequency
None
Vinyl Chloride
Max. Pred Cw
Allowable Cw
Not a POC µg/1
526.9 µg/I
'Implementation
[Are all reported values less than?
:Is the detection limit acceptable?
Yes
Yes
Limit?
Monitor?
No
No
1 Monitoring
I Frequency
None
zinc
Max. Pred Cw
Allowable Cw
82.6 µg/l
60.5 µg/I
'Implementation
!Are all reported values less than?
I Is the detection limit acceptable?
No
Yes
Limit?
Monitor?
No
Yes
1
!Monitoring
IFrequency
i
2/Month
1/2 FAV
67.0
µg/1
1
1/2 FAV
95.0
µg/I
:

/5
To AL Re acil-kreat.
C.2 e -ei L.) uu 7' P r e = T3. 2 �i
pfro ritgl
9F TrZw rr�J
Zee-
e.K t�JcJTI-
CQea. W.A.) rp
'2ieek (-)cAyrf
. ,44:40i4.
6 /L
l we
2c C = 9o.7/%

ar.44
Vi
3—r- C.2eek ,%c
/44 acl rra-o--
/
r777r;rr fi r.ti
n'1
(. i) 3.37 (3.1)
I� Ne //e..
. sa('I,3) ,j-c),( . 3 )
/ P,'s.,.ii le
67 73-r)DAQJ
36 0
Yll "rye =
1CCC NVC 3. S-sBj..) f 3c
Q ,u 5-/ & 12.,e ',,./7e
Cro
e__ '''`“3.zs-go4_ ac.
,-- 3. i C3 3) a
/ Lv. (0.3)
3? ,3 C 3/73:
e_
e
0 . `16
C f' D. '76
!t(
c F�
c t, c
c«
, 97i
0.9k6
Le.
-CF
- cr
L9A, M 7G
o. S'4-73 O. gig- OSI 7; a Mt-
( op? 6.`f422 1,7 0.-r,702

CMUD - Sugar Creek
NC0024937
Comments:
3/13/02
1) The discharge from the draft permit affects the State of South Carolina. Per 40 CFR 122.4(d)
and 40 CFR 122.44(d)(4) no permit can be issued when conditions cannot ensure compliance and
conformity with applicable water quality standards of an affected state.
Based on the RPA submitted with the permit and fact sheet, total coppe , total.zinc, and total___
silver are reportedas_amaximum predictable effluent concentration of(120.5 ug/1,_ 221.1 ug/1, and
41.0 ug/1, respectively ',The South Carolina water quality standards for these pollutants allows
for an end of pipe value accounting for hardness and dilution for chronic standards. EPA did not
find hardness data in the application and assumed a hardness of 50.0 mg/1 as CaCO3 and used an
in -stream waste concentration of 90 % for the Sugar Creek Plant resulting in end -of -pipe values
of: total copper - acute 9.2 ug/1 and chronic 7.2 ug/1 , total zinc- acute 65.0 ug/1 and chronic 65.4
ug/1, and total silver- acute 1.2 ug/1 (no chronic available). It appears that reasonable potential to
exceed South Carolina water quality standards for these pollutants exists. EPA requests that NC
fully evaluate the need for a permit limit for total copper, total zinc, and total silver with respect
to South Carolina water quality standards and provide documentation for any determination that
limits are not needed. Additionally, fecal coliform limits do not reflect SC fecal coliform
standards. The lack of appropriate permit limits which ensure compliance with applicable water
quality standards of an affected state would be a basis for an EPA objection Per 40 CFR 122.4(d)
and 40 CFR 122.44(d)(4).
2) All POTW's are required, unless impracticable, to include average weekly and average
monthly discharge limitations (40 CFR 122.45(d)(1)). The draft permit does not include a
weekly average limit for NH3-N. We recognize that this is a global issue awaiting resolution and
it remains a concern for this permit.
3) Total residual chlorine (TRC) is listed in NC water quality standards as an action level to
protect aquatic life. The draft permit provides a daily average limit TRC of 28.0 ug/1. Generally,
TRC is limited as a daily maximum to protect against acute effects. Please explain.
4) The fact sheet states that no detectable mercury concentration greater than 0.2 ug/1 has been
demonstrated since December 2000. This information was used to determine that no mercury
limit or monitoring is needed in the permit. This is inconsistent with EPA approved methods
1669 and 1631 C listing the detection limit for mercury as 0.0005 ug/1. The recent NC IG Report
documented that NC should require more sensitive analytical methods as they become available.
The use of a 0.2 ug/1 rather than a 0.0005 ug/1 detection limit is not consistent with the IG
recommendation. NC Water Quality Standards list a Mercury criterion of 0.012 ug/1 and the use
of a 0.2 ug/1 detection limit is not sufficient to determine compliance with the NC standard.
Additionally, the application data listed mercury with a maximum predictable effluent
concentration of 0.1 ug/1, which exceeds NC water quality standards. An appropriate sensitive
detection limit should be used in analyzing data used for determining appropriate permit limit per

40 CFR Part 136. EPA requests that NC re-evaluate the need for some limited further mercury
monitoring using Methods 1631C or 1669 with a re -opener in the permit if a mercury limit is
shown to be appropriate or provide a rationale if it is determined that such limited monitoring
with a more sensitive method is not needed.
5) EPA notes that the McAlpine settlement agreement references NPDES requirements for Sugar
Creek WWTP. Some of the requirements of this agreement appear to be missing from the draft
permit: Item 5 - By February 28, 2004, the City will notify SCDHEC and NCDENR as to
whether or not it intends to perform construction activities at either the Sugar Creek Plant or the
Irwin Creek Plant as part of its efforts to achieve compliance with the Total Phosphorus Limit,
and Item 2.f - If the City conducts construction activities at the Sugar Creek Plant as part of its
efforts to achieve compliance with the Total Phosphorus Limit, an effluent limitation for total
phosphorus of 334 lbs/day averaged on a monthly basis shall also apply to the Sugar Creek Plant
commencing on February 28, 2007. The settlement agreement, Item 6, does state that NCDENR
shall issue NPDES permits for the Sugar Creek and Irwin Creek Plan with effluent limits for
total phosphorus and with construction notification requirements consistent with the provisions
of Section 2 and 5 of the settlement agreement. Please explain the lack of these requirements in
this permit?.
6) EPA notes that the proposed expiration date of the permit is June 30, 2005, which is prior to
the provisions of the settlement agreement. Please explain this discrepancy.

T°`1Q
Oneway Analysis of VALUE Silver By STATION
700
600
500
400
300
200
100
0
VALUE Silver
C8896500
i
Quantiles
Level Minimum 10% 25% Median 75% 90% Maximum
C8896500 5 5 5 5 5 5 5
C9050000 5 5 5 347.5 690 690 690
C9210000 5 5 5 5 5 5 5
C9370000 5 5 5 5 5 5 5
Means and Std Deviations
Level Number Mean Std Dev Std Err Mean Lower 95% Upper 95%
C8896500 1 5.000
C9050000 2 347.500 484.368 342.50 -4004 4699.4
C9210000 1 5.000
C9370000 2 5.000 0.000 0.00 5 5.0
C9050000
C9210000
STATION
C9370000

•
•
Basic box and whisker plots of the measurements from each station by parameter. (Steve Kroeger; JMP v 4)
03/19/02 09:56 AM
DataTable=M_Myers_Split,Source=
Oneway Analysis of VALUE Copper By STATION
200-
o. -
0. .
0
U .
W
100-
0
•
C8896500
C9050000 C9210000
te STATION • t
C9370000
Quantiles
Level Minimum 10% 25% Median 75% 90% Maximum
C8896500 2 2 3 6 14 21.6 90
C9050000 2.4 5 6 9.8 15 30 240
C9210000 2 3.28 4.75 6.1 9.1 16 47
C9370000 2 2 2.9 5 11 21.2 40
Means and Std Deviations
Level Number Mean Std Dev Std Err Mean Lower 95% Upper 95%
C8896500 161 11.0714 12.6372 0.9960 9.105 13.038
C9050000 149 15.3879 24.8222 • 2.0335 11.369 Tf9.4o67
C9210000 117 8.7009 7.8549 0.7262 7.263 10.139
C9370000 147 9.5143 10.3137 0.8507 7.833 .11.19C

Oneway Analysis of VALUE Zinc By STATION
VALUE Zinc
900-
800-
700-
600-
500-
400-
300-
200-
100
0
•
C8896500
C9050000
1
C9210000
C9370000
STATION
Quantiles
Level Minimum
C8896500 10
C9050000 10
C9210000 10
C9370000 10
Means and Std Deviations
Level
C8896500
C9050000
C9210000
C9370000
Number
162
162
117
147
10% 25% Median 75%
10 10 20 40
20.3 29.75 44 63
10 16 23 34
10 10 11 22
Mean Std Dev Std Err Mean Lower 95%
44.8580 89.0108 6.9933 31.048
55.7531 50.0538 3.9326 47.987
31.8034 32.4909 3.0038 25.854
21.1565 20.5225 1.6927 17.811
90%
89.1
91.4
58.8
50
Maximum
920
440
230
160
Upper 95%
58.669
63.519
37.753
24.502

�y
Oneway Analysis of VALUE Hardness BySTATION
600
500-
400-
300
2001
100—
VALUE Hardness
0
:C
C8896500
C9050000 C9210000 C9370000
STATION
Quantiles
\ Level
C88965
0500001
0000
C9370 )156
Means and Std Deviations
Level Number
C8896500
C9050000
C9210000
C9370000
Minimum 10% 25% Median 75% 90% Maximum
9 56.336 79.39 95 110 110 130
58 67 76 84.84 95.4 586
6 51.6 59 65.28 73 82 100
39 53.04 64 74 86 110
Mean Std Dev Std Err Mean Lower 95% Upper 95%
153 89.9838 22.3720 1.8087 86.410 93.557
155 79.8392 43.3350 3.4808 72.963 86.715
117 66.1298 12.9136 1.1939 63.765 68.494
139 63.5010 18.2136 1.5449 60.446 66.556

Oneway Analysis of VALUE pH By STATION
O.
w
-f-
J
C8896500
C9050000 C9210000 C9370000
STATION
Quantiles
Level Minimum
C8896500 6.3
C9050000 6.1
C9210000 6.6
C9370000 5.47
Means and Std Deviations
Level Number
C8896500 178
C9050000 250
C9210000 131
C9370000 214
10% 25% Median
6.9 7.2 7.48
6.8 7.1 7.3
7.2 7.3 7.4
6.8 7.075 7.3
Mean Std Dev Std Err Mean
7.52713 0.563330 0.04222
7.25064 0.293723 0.01858
7.41870 0.232681 0.02033
7.28322 0.408690 0.02794
75%
7.755
7.4525
7.52
7.52
Lower 95%
7.4438
7.2141
7.3785
7.2282
90%
8.315
7.6
7.7
7.7
Maximum
9.6
8.19
8.2
8.9
Upper 95%
7.6105
7.2872
7.4589
7.3383

Effluent Monitoring Data*
NPDES # NAME PARAMETER NAME UNITS CODE Item
MONTH
Oct 2000 Nov 2000 Dec 2000 Jan 2001 Feb 2001 Mar 2001 Apr 2001 May 2001 Jun 2001 Ju12001 Aug 2001 Sep 2001 12-Month
Summary
NC0024945 Total 10.137
NC0024945 CMUD - IRWIN CREEK WWTP FLOW MGD 50050 Avg. 9.558 9.06 8.0322 8.7516 9.7464 11.4903 11.3033 10.6096 10.6366 10.6741 10.8225 10.96 10.137
Max. 11.6 11.5 15.6 12.4 12.5 17.8 13.8 13 14.9 16.7 16.9 13.2 17.8
Min. 6.2 3.7 4.2 6.3 5.4 6.2 9.3 8.6 4.1 1.6 4.1 8 1.6
CBOD, (5-DAY) 20C MG/L 80082 Avg. 1.55 2.06 2.82 5.23 3.87 2.56 329 3.75 2.33 1.99 2 0.75 2.683
Max. 5 3.9 5.5 8.4 8.3 5.1 4.7 8.5 4.3 7.1 52 3 8.5
Min. 0 0 0 2.3 0 0 2.1 2.3 0 0 0 0 0
TOTAL SUSPENDED SOUDS MG/L 00530 Avg. 1.5 2.2 3.1 4.3 3.3 1.7 2 3.3 2 1.8 2.5 1 2.392
Max. 5.4 5.5 11 10 9.8 3.7 6.5 5.1 5.2 6.9 18.2 3.2 18.2
Min. 0 0 0 1.9 0 0 0 1.8 0 0 0 0 0
AMMONIA (AS N) MG/L 00610 Avg. 0.09 0.11 0.95 1.12 1.43 0.09 0.21 0.09 0.23 0.41 0.19 023 0.429
Max. 0.7 0.5 4.6 4.6 82 0.5 1.3 0.6 1.1 1.7 1.2 1.3 8.2
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
FECAL COLIFORM #/100ML 31616 Avg. 35.3 7.9 1.9 1.8 22 5.9 12.3 21.3 10.1 26.8 20.6 26.1 9.394
Max. 360 47 900 500 55 280 1000 2000 210 360 410 3200 3200
Min. 0 0 0 0 0 0 0 0 0 1 1 0 0
TOTAL RESIDUAL CHLORINE UG/L 50060 Avg. 0281 0 0.421 0 0.789 1.38 0.25 0 0.619 0.476 0 5263 0.790
Max. 6.2 0 8 0 10 10 5 0 13 10 0 100 100
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
TOTAL NITROGEN (AS N) MG/L 00600 Avg. 18.95 19.7 20.2 16.1 20.4 14.9 19.5 17.78 16.275 18 20.12 18.08 18.334
Max. 20.6 19.7 20.2 16.1 20.4 17.1 25.4 19.5 23.6 212 292 24.4 29.2
Min. 17.3 19.7 202 16.1 20.4 112 16.5 15.5 12.8 13.4 16.1 14.5 112
NITRITE PLUS NITRATE (AS N) MG/L 00630 Avg. 19.04 17.947 15.984 13.333 14.875 13.3 18.225 16.58 15.525 17 18.86 17.38 16.504
Max. 24.7 21.7 21.7 21.3 17 18.3 24.7 17.7 22.1 20 28.1 22.8 28.1
Min. 13.3 14.2 11.2 7.6 11.1 8.1 15.4 14.8 11.3 12.9 15 13.7 7.6
TOTAL PHOSPHORUS (AS P) MGJL 00665 Avg. 1.8 2 2 1 2.16 1.85 2.075 2.36 2275 2.32 2.6 2.16 2.050
Max. 1.9 2 2 1 2.9 22 2.5 2.6 2.7 2.7 3.5 2.5 3.5
Min. 1.7 2 2 1 1.6 1.4 1.6 2.1 1.8 1.9 2.3 1.8 1
TEMPERATURE (C) DEG.0 00010 Avg. 21.53 17.86 13.91 13.22 14.79 14.91 18.69 22 25.1 26.16 26.83 24.72 19.977
Max. 24 22.1 15.4 14.9 17.1 16.6 21.5 24.1 26.1 27 27.6 26 27.6
Min. 17.3 13.8 12.1 11.2 13 13.6 15.4 20.4 23.4 25.6 25.7 22.9 112
SPECIFIC CONDUCTANCE uMHOS/CM 00095 Avg. 557.7 489.8 468.5 441 476 420.9 492.4 533.1 573.3 575.1 624.1 527.9 514.983
Max. 644 597 542 549 574 504 583 624 640 707 766 624 766
Min. 454 357 360 349 343 268 387 445 485 506 519 421 268
DISSOLVED OXYGEN (D0) MG/L 00300 Avg. 8.02 8.89 10.02 10.13 9.67 9.65 9 8.58 7.93 7.71 7.5 7.7 8.733
Max. 8.4 9.7 10.6 10.9 10.1 10 9.7 9.1 8.2 8.2 8 7.9 10.9
Min. 7.5 82 9.3 9 8.6 9.3 8.5 8.3 7.7 7.4 7.2 7.4 72
TOTAL CYANIDE (AS CN) UG/L 00720 Avg. 2.5 2.3923 2.7 3.9466 325 0 0 0 0 0 0 0 1.232
Max. 4 5.6 5.8 11 7.3 0 0 0 0 0 0 0 11
Min. 1 0.7 0.7 0.9 0.9 0 0 0 0 0 0 0 0
TOTAL CADMIUM (AS CD) UG/L 01027 Avg. 0 0 0 0 0 0 0 0 0 0.22 0 0 0.018
Max. 0 0 0 0 0 0 0 0 0 1.1 0 0 1.1
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
TOTAL COPPER (AS CU) UG/L 01042 Avg. 112 52 6.475 725 6.8 7.5 5.8 5.98 7.875 8.8 7.52 6 7200
Max. 29 6 72 9 8 12 7.1 7.6 14 14 9.8 11 29
Min. 4 5 5.7 6 4 5 5 5.3 5 3.8 4.9 4.1 3.8
TOTAL LEAD (AS PB) UG/L 01051 Avg. 0 0 0 0 0 0 0 0 0 0 0 0 -
Max. 0 0 0 0 0 0 0 0 0 0 0 0 0
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
•
See separate sheets for pH and toxicity data.
effluentdatal ads,DataSumm
12/19/2001

Effluent Monitoring Data*
MONTH
NPDES # NAME PARAMETER NAME UNITS CODE Item
TOTAL SILVER (AS 1 G)
TOTAL ZINC (AS ZN
TOTAL MERCURY (AS HG)
UG/L 01077 Avg.
Max.
Min.
UG/L 01092 Avg.
Max.
Min.
UG/L 71900 Avg.
Max.
Min.
Oct 2000 Nov 2000 Dec 2000 Jan 2001 Feb 2001 Mar 2001 Apr 2001 May 2001 Jun 2001 Jul 2001 Aug 2001 Sep 2001 12-Month
Summary
0 0 0 1 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0 0 0 0 0
73.8 54.4 67.75 1 87.75 95.8 76.25 61.5 72.2 61.5 68.6 51.4 48.8333 68.315
99 74 83 110 180 98 69 100 68 96 72 77 180
54 39 54 70 57 49 50 53 58 48 38 32 32
0 0.06 0.075 0 0 0 0 0 0 0 0 0 0.011
0 0.3 0.3, 0 0 0 0 0 0 0 0 0 0.3
0 0 0 I 0 0 0 0 0 0 0 0 0 0
' See separate sheets for pH and toxicity data.
efluentdatal .xis,DataSumrrl
12/19/2001 •

Effluent Monitoring Data*
NPDES # NAME PARAMETER NAME UNITS CODE Item
MONTH
-Month
Oct 1999 Nov 1999 Dec 1999 Jan 2000 Feb 2000 Mar 2000 Apr 2000 May 2000 Jun 2000 Jul 2000 Aug 2000 Sep 2000 1 Suummarymmary
NC0024945 Total
NC0024945 CMUD - IRW1N CREEK WWTP FLOW MGD 50050 Avg. 10.5322 9.52 9.7225 10.4903 10.6689 10.3645 10.9933 8.787 9.7533 9.1967 9.8064 10.5666 10.033
Max. 17 11.4 12.9 14.3 16.5 13.2 20.3 12.1 12 11.1 12.1 15 20.3
Min. 7.5 5.8 6.3 6.5 5.1 3.3 42 0.5 6.7 5.7 7.1 8.7 0.5
CBOD, (5-DAY) 20C MG/L 80082 Avg. 5.67 4.86 5.99 4.95 5.7 5.08 4.76 5.57 1.79 1.78 2.6 1.27 4.168
Max. 9.8 7 10 9.5 13.8 9.8 7.4 17.6 3.7 4.6 5 3.7 17.6
Min. 3.2 3.1 3.6 0 2.8 2.7 3.1 0 0 0 0 0 0
TOTAL SUSPENDED SOLIDS MG/L 00530 Avg. 17.3 11 11.8 10.5 9.6 11.7 11.2 9.9 1.7 2.5 1.2 0.7 8.258
Max. 26 24.5 37 27 60 25.3 44 42 3 14 4.5 1.7 60
Min. 7 3.1 4.7 3.2 1.3 2.6 4 0 0 0 0 0 0
AMMONIA (AS N) MG/L 00610 Avg. 0.44 0.42 0.48 0.5 1.43 0.43 0.64 0.44 02 0.12 0.55 02 0.488
Max. 1.8 1.3 2.7 3.1 6.7 2.5 4.7 1.9 1.3 2.4 1.9 1 6.7
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
FECAL COLIFORM #/100ML 31616 Avg. 12.2 5.8 3.5 3.1 4.7 16.3 25.3 89.1 103.3 56.3 6.3 37.5 15.430
Max. 73 173 27 1200 200 800 4100 6000 600 460 470 290 6000
Min. 0 0 0 0 0 6 2 9 8 3 0 2 0
TOTAL RESIDUAL CHLORINE UG/L 50060 Avg. 0 0 0 31.736 39.476 0.552 0 028 1.068 0.905 0.721 1.15 6.324
Max. 0 0 0 603 499 12.7 0 5.6 6.3 7.4 6.3 23 603
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
TOTAL NITROGEN (AS N) MG/L 00600 Avg. 18.88 19.633 21.48 16.4 17.575 13.9 22.166 10.5 19.8 19 10.8 14.2 17.028
Max. 28 24.7 26.4 20.6 25 21.4 27.5 10.5 19.8 19 10.8 142 28
Min. 11.7 16 17 11.6 9.4 10 15.8 10.5 19.8 19 10.8 14.2 9.4
NITRITE PLUS NITRATE (AS N) MG/L 00630 Avg. 17.56 19.366 19.8 14.75 15.875 12.52 18.2 17.927 15.572 17.461 14.354 16.015 16.617
Max. 27 24.7 25 18 22.9 20 27 32 22 24 19.7 20.3 32
Min. 8.8 16 16 10 8.4 8.6 14 8.7 4.5 12 10.3 10.8 4.5
TOTAL PHOSPHORUS (AS P) MG/L 00665 Avg. 3.4 1.8 2.1 1.8 3.4 1.9 3.8 1.6 2.8 2.3 1.4 12 2.292
Max. 3.4 1.8 2.1 1.8 3.4 1.9 3.8 1.6 2.8 2.3 1.4 1.2 3.8
Min. 3.4 1.8 2.1 1.8 3.4 1.9 3.8 1.6 2.8 2.3 1.4 1.2 1.2
TEMPERATURE (C) DEG.0 00010 Avg. 22.38 20 16.58 14.21 13.64 16.8 18.24 22 25.85 26.7 26.95 25.08 20.703
Max. 25 22 19 18 16.1 18.7 19.2 25 28 28 29 27 29
Min. 19 18 14 11 11 15 16.5 19 23 25 26 23 11
SPECIFIC CONDUCTANCE uMHOS/CM 00095 Avg. 586.3 565.8 518.3 503.6 516 502.6 5202 562.7 560.8 554.5 546.6 525.1 538.542
Max. 781 688 618 571 632 691 621 814 652 699 638 599 814
Min. 426 437 424 404 391 405 366 435 451 420 421 434 366
DISSOLVED OXYGEN (DO) MG/L 00300 Avg. 8.16 8.66 9.13 9.74 9.71 8.9 8.8 8.4 8.04 7.69 7.6 7.77 8.550
Max. 8.7 9.1 9.7 10.4 10.5 9.4 9.2 92 8.5 7.9 8 8.1 10.5
Min. 7.4 8.4 8.2 9.2 9 8.4 8.4 6.8 7.6 7.4 7.4 7.4 6.8
TOTAL CYANIDE (AS CN) UG/L 00720 Avg. 4.3846 2.3846 1.875 2.5 2 1.7857 1.0416 1.4285 1.4615 2.0785 1.8571 2.2571 2.088
Max. 9 5 8 7 5 3 2.7 3 4 3.8 3 6.1 9
Min. 0 0 0 0 0 1 0 0 0 0 0 0 0
TOTAL CADMIUM (AS CD) UG/L 01027 Avg. 0 0 0 0 0 0 0 0 0 0 0 0
Max. 0 0 0 0 0 0 0 0 0 0 0 0 0
Min. 0 0 0' 0 0 0 0 0 0 0 0 0 0
TOTAL COPPER (AS CU) UG/L 01042 Avg. 7.25 8.5 8.6 9.6666 11 11.25 10 11.4 7 8.12 6.6666 5.825 8.773
Max. 9 15 15 16 25 18 15 24 10 12 10 9 25
Min. 4 6 4 5 5 7 6 5 5 6.1 4 4 4
TOTAL LEAD (AS PB) UG/L 01051 Avg. 0 0.6666 0.9 0 0 1.5 0 1.98 0 0 0 0 0.421
Max. 0 4 4.5 0 0 6 0 9.9 0 0 0 0 9.9
Min. 0 0 0 0 0 0 0 0 0 0 0 0 0
' See separate sheets for pH and toxicity data.
effuentdatal .xls,DataSumm
12/19/2001

. • Effluent Monitoring Data*
MONTH
NPDES # NAME PARAMETER NAME UNITS CODE Item
TOTAL SILVER (AS AG)
TOTAL ZINC (AS ZN
TOTAL MERCURY (AS HG)
UG/L 01077 Avg.
Max.
Min.
UG/L 01092 Avg.
Max.
Min.
UG/L 71900 Avg.
Max.
Min.
Oct 1999 Nov 1999 Dec 1999 Jan 2000 Feb 2000 Mar 2000 Apr 2000 May 2000 Jun 2000 Jul 2000 Aug 2000 Sep 2000 12-Month
Summary
0 1.3333 1.16 0.3333 0.5 0 0 1.04 0 0 0 0 0.364
0 4 5.8 2 2 0 0 5.2 0 0 0 0 5.8
0 0 0 0 0 0 0 0 0 0 0 0 0
92.5 100.5 73.4 92.6666 87.75 141.25 162.5 167.2 88.4 82.6 61.1666 68.25 101.515
112 240 118 122 100 189 250 280 140 91 73 105 280
68 48 46 79 79 67 100 96 61 69 51 35 35
0 0 0 0 0 0 0 0 0 0 0 0.05 0.004
0 0 0 0 0 0 0 0 0 0 0 0.2 0.2
0 0 0 0 0 0 0 0 0 0 0 0 0
' See separate sheets for pH and toxicity data.
eifl uentdata 1. xes, DataSu mnz
12/19/2001 44

Effluent Monitoring Data - Toxicity
NPDES##
FACILITY NAME
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD•IRWIN CREEK
NC0024945 CMUD•IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD•IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 CMUD-IRWIN CREEK
NC0024945 Total
PARAMETER
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
CHRONIC TOX, P/F 7DAY
NAME
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CERIODAPHNIA
CODE UNITS MONTH RESULT
TGP3B PASS/FAIL 199910 NO DATA
TGP3B PASS/FAIL 199911 PASS
TGP3B PASS/FAIL 199912 NO DATA
TGP3B PASS/FAIL 200001 PASS
TGP3B PASS/FAIL 200002 NO DATA
TGP3B PASS/FAIL 200003 NO DATA
TGP3B PASS/FAIL 200004 100
TGP3B PASS/FAIL 200005 100
TGP3B PASS/FAIL 200006 NO DATA
TGP3B PASS/FAIL 200007 FAIL
TGP3B PASS/FAIL 200008 PASS
TGP3B PASS/FAIL 200009 PASS
TGP3B PASS/FAIL 200010 100
TGP3B PASS/FAIL 200011 NO DATA
TGP3B PASS/FAIL 200012 NO DATA
TGP3B PASS/FAIL 200101 NO DATA
TGP3B PASS/FAIL 200102 NO DATA
TGP3B PASS/FAIL 200103 NO DATA
TGP3B PASS/FAIL 200104 PASS
TGP3B PASS/FAIL 200105 NO DATA
TGP3B PASS/FAIL 200106 NO DATA
TGP3B PASS/FAIL 200107 NO DATA
TGP3B PASS/FAIL 200108 NO DATA
TGP3B PASS/FAIL 200109 NO DATA
effluentdatal .xls,Toxicity
12/19/2001

• Effluent Monitoring Data - pH
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 199910 7.2 6.6
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 199911 7 4.9
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 199912 7.1 4.9
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200001 7 6.4
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200002 7.1 6.3
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200003 7.3 6.6
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200004 7.2 6.7
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200005 7.3 6.4
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200006 7.5 6.9
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200007 7.3 6.7
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200008 7.3 6.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200009 7.5 6.7
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200010 7.5 6.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200011 7.4 6.3
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200012 7.2 6.4
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200101 7.4 6.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200102 7.5 6.7
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200103 7.5 6.9
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200104 7.4 6.5
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200105 7.2 6.1
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200106 7.4 5.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200107 7.3 5.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200108 7.5 6.8
NC0024945 CMUD-IRWIN CREEK pH 00400 SU 200109 7.9 6.9
NC0024945 Count 24
effluentdatal.xls,pH
12/19/2001

VIOLATIONS (all Types) for:
Permit NC0024945
Facility Nami
DMRs Betweer 1-1997 and 12- 2001
Region %
County
Page: 1 of 2
Report Date: 01/10/02
PERMIT: NC0024945
FACILITY: Irwin Creek WWTP
COUNTY: Mecklenburg
REGION: Mooresville
LIMIT VIOLATIONS:
DMR
09-2001
06-2001
07-2001
OUTFALL
001
001
001
MONITORING VIOLATIONS:
LOCATION PARAMETER
Effluent
Effluent
Effluent
CHLORINE, TOTALRESIDUAL
PH
PH
VIOLATION DATE
09/28/01
06/01/01
07/18/01
UNIT OF
MEASURE
ug/l
su
su
LIMIT
28.00
6.00
6.00
CALCULATED
FROM REPORTED
100.00
5.80
5.80
VIOLATION DESCRIPTION
Daily Maximum Exceeded
Daily Minimum Not Reached
Daily Minimum Not Reached
DMR OUTFALL LOCATION PARAMETER
09-2001 001 Effluent BOD, CARBONACEOUS 05 DAY,
20C
09-2001 001 Effluent CHLORINE,TOTALRESIDUAL
09-2001 001 Effluent
09-2001 001 Effluent
09-2001 00I Effluent
COLIFORM, FECAL MF, M-FC
BROTH,44.5C
NITRITE PLUS NITRATE TOTAL 1
DET. (AS N)
NITROGEN, AMMONIA TOTAL
(AS N)
09-2001 ((01 Effluent OXYGEN, DISSOLVED (DO)
09-2001 (101 Effluent PH
09-2001 00I Effluent SOLIDS, TOTAL SUSPENDED
09-2001 0(I1 Effluent SPECIFIC CONDUCTANCE
09-20(11 0(I1 Effluent TEMPERATURE, WATER DEG.
CENTIGRADE
REPORTING VIOLATIONS:
VIOLATION DATE MEASUREMENT FREQUENCY
09/03/01
09/03/01
09/03/01
09/30/01
09/03/01
09/03/01
09/03/01
09/03/01
09/03/01
09/03/0
Daily — weekdays
Daily -- weekdays
Daily — weekdays
Weekly
Daily — weckdays
Daily — weckdays
Daily — weekdays
Daily -- weekdays
Daily — weekdays
Daily — weekdays
VIOLATION DESCRIPTION
Frequency Violation
Frequency Violation
Frequency Violation
Sample Type Violation
Frequency Violation
Frequency Violation
Frequency Violation
Frequency Violation
Frequency Violation
Frequency Violation
DMR OUTFALL
09-2001 001
09-200I 001
09-2001 001
LOCATION PARAMETER
Effluent BOD, 5-DAY (20 DEG. C)
Effluent
Effluent
CHROMIUM, TOTAL (AS CR)
CHV STATRE 7DAY CHR
CERIODAPHNIA
VIOLATION DATE
09/30/01
09/3(1/01
09/30/01
VIOLATION DESCRIPTION
Parameter Missing
Parameter Missing
Parameter Missing

VIOLATIONS (all Types) for:
Permit NC0024945
Facility Nam( %
DMRs Betweer 1-1997 and 12-2001 Region %
County %
09-2001 001 Effluent NICKEL, TOTAL (AS NI) 09/30/01 Parameter Missing
09-2001 001 Effluent NITROGEN, KJELDAHL TOTA1 09/30/01 Parameter Missing
(AS N)
09-2001 001 Effluent OXYGEN DEMAND, CHEM. 09/30/01 Parameter Missing
(HIGH LEVEL) (COD)
09-2001 001 Effluent P/F STAT 48HR ACU 09/30/01 Parameter Missing
CERIODAPHNIA
09-2001 001 Effluent SOLIDS, SETTLEABLE 09/30/01 Parameter Missing
09-2001 001 Effluent SOLIDS, TOTAL 09/30/01 Parameter Missing
Page: 2 of 2
Report Date: 01/10/02

Residual Chlorine and Ammonia Toxicity Assessment
Residual Chlorine
s7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (UG/L)
UPS BACKGROUND LEVEL (U
IWC (%)
Allowable Concentration (ug/
Fecal Limit
Ratio of 0.2 :1
23.25
17.0
0
82.59
20.58
Ammonia as NH3
(summer)
s7Q10 (CFS)
DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
UPS BACKGROUND LEVEL
IWC (%)
Allowable Concentration (m
Ammonia as NH3
(winter)
w7Q10 (CFS)
2001100mI DESIGN FLOW (MGD)
DESIGN FLOW (CFS)
STREAM STD (MG/L)
UPS BACKGROUND LEVEL
IWC (%)
Allowable Concentration (m
4.9
15
23.25
1.0
0.22
82.59
1.16
7.7
15_
23.25
1.8
0.22
75.12
2.32
1/10/2002
MJM
NC0024945

To: Permits and Engineering Unit
Water Quality Section
Attention: Mike Myers
SOC PRIORITY PROJECT: No
Date: August 29, 2001
NPDES STAFF REPORT AND RECOMMENDATIONS
County: Mecklenburg
NPDES Permit No.: NC0024945
MRO No.: 01-59
PART I - GENERAL INFORMATION ` %
1. Facility and Address: Irwin Creek WWTP
CMUD
5100 Brookshire Boulevard
Charlotte, N.C. 28216
2. Date of Investigation: June 12, 2001
3. Report Prepared By: Michael L. Parker, Environmental Engineer II
4. Person Contacted and Telephone Number: Tom Hunter, [phone].
5. Directions to Site: From the intersection of I-77 and Woodlawn Rd. in the City of Charlotte,
travel west on Woodlawn Rd. (turns into Billy Graham Parkway) 1.0 mile. Turn right
(north) onto Westmont Drive. The WWTP is located at the end of Westmont Drive.
6. Discharge Point(s), List for all discharge Points: -
Latitude: 35 ° 11' 44"
Longitude: 80° 54' 27"
Attach a USGS Map Extract and indicate treatment plant site and discharge point on map.
USGS Quad No.: G 15 NW
7. Site size and expansion area consistent with application: Yes. Limited area is available for
expansion, if necessary.
8. Topography (relationship to flood plain included): Flat to moderate slopes. A significant
portion of the WWTP site appears to be located within the 100 year flood plain, however,
those treatment units located within the flood plain are protected from flooding by a dike
specifically designed for this purpose.
9. Location of Nearest Dwelling: Approx. 1000± feet from the WWTP site.

Page Two
10. Receiving Stream or Affected Surface Waters: Irwin Creek
a. Classification: C
b. River Basin and Subbasin No.: Catawba 030834
c. Describe receiving stream features and pertinent downstream uses: Excellent flow in
receiving stream (8-10 feet wide x 1-2 feet deep). Irwin Creek has a predominately
urban watershed. There are no other known dischargers below this facility.
PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1, a. Volume of Wastewater: 15.0 MGD (Design Capacity)
b. What is the current permitted capacity: 15.0 MGD
c. Actual treatment capacity of current facility (current design capacity): 15.0 MGD
d. Date(s) and construction activities allowed by previous ATCs issued in the previous
two years: N/A
e. Description of existing or substantially constructed WWT facilities (outfall 001): The
existing WWT facilities consist of an influent pump station followed by mechanical
screening, grit removal, influent flow measurement, three (3) primary clarifiers, four
(4) trickling filters, pH adjustment (NaOH), eleven aeration basins (diffused), three
(3) secondary clarifiers, ten (10) tertiary filter cells with a filter backwash collection
basin, gaseous chlorination with contact chamber, dechlorination (Sodium Bisulfite),
cascade aeration, four (4) anaerobic digesters, a 300,000 gallon sludge storage tank
(aerated), two (2) gravity belt thickeners with polymer feed, a 1.8 MG digested
sludge storage tank, and two (2) belt filter presses. This facility has also recently
constructed a flow equalization system consisting of a pump station, two (2) bar
screens with screenings compactors, a gravity grit removal system, and two (2)
retention basins having a total capacity of 35 MG.
Outfall 002 utilizes basically the same treatment facilities noted above, however,
outfall 002 by-passes the sand filters and the cascade aeration. This outfall is only
used when the sand filters are being repaired or when effluent quality is sufficient to
consistently meet Permit limitations.
f. Description of proposed WWT facilities: Other treatment units planned, but not yet
permitted for this facility include rehab to the primary clarifiers and pump station,
sludge dewatering improvements (possibly including a new belt filter press), and
exploring new disinfection processes (other than chlorine).
g•
Possible toxic impacts to surface waters: This facility has a history of consistently
passing its toxicity testing for the past three (3) years.
h. Pretreatment Program (POTWs only): Approved.

Page Three
2. Residual handling and utilization/disposal scheme:
a. If residuals are being land applied specify DWQ Permit No. WQ000057.
Residuals Contractor: Synagro, Inc.
Telephone No. [phone]
3. Treatment Plant Classification: Class IV (there has been no change from previous rating)
4. SIC Code(s): 4952 Wastewater Code(s): 01
5. MTU Code(s): 04103
PART III - OTHER PERTINENT INFORMATION
1. Is this facility being constructed with Construction Grant Funds or are any public monies
involved (municipals only)? Public monies were used in the construction of this facility.
2. Special monitoring or limitations (including toxicity) requests: None at this time.
3. Important SOC/JOC or Compliance Schedule dates: N/A
PART IV - EVALUATION AND RECOMMENDATIONS
The Charlotte -Mecklenburg Utility Department (CMUD) has requested renewal of the subject
permit. There have been some changes/additions to the existing treatment facility since the Permit
was last renewed. See Part II, No. 1(e) above for a complete listing of all current treatment
components. A recent CEI conducted at this facility on February 26, 2001 by staff with this Office
indicated that the existing treatment units appeared to be properly operated and maintained with the
exception of a couple of minor deficiencies which were noted.
Pending receipt and approval of the WLA, it is recommended that the Permit be renewed as
requested.
Sign • ure of Repo
eparer 1 ate
Water Quality Regi •1 Supervisor Date
h:ldsrldsrO 11lnvin.sr

•
March 2, 2001
Mr. Charles H. Weaver, Jr.
NC DENR / Water Quality / NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
(0),
CHARLOTTEsm
%AR —7 2001
Subject: Renewal of NPDES Permit NC I 45E i.
Irwin Creek WWTP
Mecklenburg County
Dear Mr. Weaver,
This cover letter and attached NPDES Permit Application constitute our request to renew the subject
NPDES Permit that expires on August 31, 2001. We are sending the original letter and completed
application form and two additional copies of each as directed. We understand that no renewal fee
payment is required as part of this application and that this package includes all that is required of us
to apply for this renewal.
Irwin Creek currently operates under an NPDES Permit that became effective November 1, 1996.
During this permitting period, a 500-year flood occurred in July of 1997 that resulted in significant
damage to this facility. Due to this occurrence, the need to modernize the facility, and increased
awareness of capacity challenges during storm events, several upgrades and structural verifications
have been completed in this time. These changes include:
❑ Verification that the structural integrity of the elevated influent pipeline over the stream that
flooded was completed;
❑ Flow equalization for storm events is currently under construction and is scheduled for
completion in April 2001. This structure is included with the description of the current
operating status, since completion will occur prior to the expiration of the current permit;
❑ New Bar Screens;
❑ New Grit Removal facility;
❑ Two new variable frequency drive (VFD) pumps were installed at the influent lift station;
o The trickling filters were completely rehabilitated with a new trickling filter pump station and
new random dump artificial media;
❑ An eleventh aeration tank was built;
o Changed the air distribution system in the aeration tanks to fine bubble diffusers;
❑ Installed four new process blowers;
❑ Constructed three new secondary clarifiers. Two if the three existing secondary clarifiers have
been demolished, with the third secondary clarifier being used for collecting back wash water
Environmental Management Division 5100 Brookshire Blvd. Charlotte, NC 28216
Phone: [phone] Fax: [phone] Charlotte -Mecklenburg Utilities

CHARLOTTESM
from the effluent anthracite filters;
o A Waste Activated Sludge (WAS) thickening building has been constructed. This building
includes WAS storage and two gravity belt thickeners;
o Sludge storage facility — this facility is maintained by the contract operator that handles CMU's
residuals contract
❑ Four of the six floating cover digesters were cleaned out and re -habilitated with fixed cover,
motorized valves and mechanical mixing;
❑ The other two floating cover digesters were cleaned out and the cover repaired;
❑ Two new boilers and spiral heat exchangers were installed for heating the digesters
❑ Effluent anthracite filters were constructed
❑ Dechlorination with sodium bi-sulfite was added;
❑ A cascade aerator
This facility is currently permitted with two discharge pipes. Pipe 001 is piped to Irwin Creek after the
cascade aerator. Pipe 002 is a spill way that is currently closed with a gate. This Pipe has not been
evaluated completely to see if the discharge point should be eliminated. However, the gate over the
spillway has not be opened for at least six years, and an evaluation to permanently close this
discharge point will be started in the near future. The on -going upgrades at this facility have over
shadowed the need for this review. We request both pipes be maintained in the new permit.
Please confirm your receipt of this application package. Please let me know if you need additional
information or clarification. I can be reached at [phone] or iiarrelk ci.charlotte.nc.us. We look
forward to hearing from you.
Respectfully,
G c 1 „SS,
cqueline A. Jarrell, P.E.
uperintendent of Environmental Management Division
Cc: Dawn Padgett
Tom Hunter
File
Environmental Management Division 5100 Brookshire Blvd. Charlotte, NC 28216
Phone: [phone] Fax: [phone] Charlotte -Mecklenburg Utilities

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Mitchum, Inc.
Street address 2001 West Morehead Street
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address none
Zip Code 28208
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Potato chips
1300
LbsJday
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.045 MGD
x Continuous
22 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
fI
Name of SIU Borg Warner Automotive —
Street address 5019 Hovis Rd.
/- 6i t L S y s j E P-1 S L C
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address
Zip Code 28208
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Aluminum and steel fuel tanks for
trucks
Steel and aluminum, phosphating and etching
agents and paint
350
Tanks/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.020 MGD
x Intermittent
8 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows >1 MGD or with pretreatment programs
SECTION I11. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU PalEx Container Systems .FC `
Street address 2900 West Trade St.
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Steel Drums
Used steel drums
1700
Drums/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.015 MGD
x Continuous
23 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows >1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU,
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal systeneceiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Allied Zinc Finishing, Inc.
Street address 919 Berryhill Road
City Charlotte
County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address
/
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility, SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Zinc plated and chromate coated
metal parts
Caustics, acids, zinc chlorides, potassium
chlorides, Ammonia chlorides, chromates
Approx. 220,000
Lbs/month
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.012 MGD
x Continuous
5 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Aramark Uniform Services, Incorporated
Street address 2321 Wilkinson Boulevard
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number N/A
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Washed, ,dried and pressed
uniforms, mats, and mops, etc.
Conventional detergents (sodium metasilicates,
caustic soda) sulfactants, bleach, dyes, and
starch
60,000 —100,000
pieces a day
250,000 Ibs a
day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.100 MGD
x Continuous
6 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Aramark Uniform Services, Incorporated
Street address 2321 Wilkinson Boulevard
City Charlotte
State NC
Telephone Number
Fax Number
e-mail address
County Mecklenburg
Zip Code 28208
[phone]
N/A
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Washed, ,dried and pressed
uniforms, mats, and mops, etc.
Conventional detergents (sodium metasilicates,
caustic soda) sulfactants, bleach, dyes, and
starch
60,000 —100,000
pieces a day
250,000 Ibs a
day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.100 MGD
x Continuous
6 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 1I1. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Trane Service First
Street address 4500 Morris Field Dr.
City Charlotte County Mecklenburg
_ State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Cooling System Compressors
Used compressors
42
Compressors/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.010 MGD x Continuous
30 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU BASF Corp.
Street address 4330 Chesapeake Dr.
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
Zip Code 28216
[phone]
[phone]
e-mail address youngml @basf.com
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Acrylonitrile and Acrylic Acid products
3,171,829
Lbs./year
Acrylic Acid products
830,000
Lbs./year
Formaldehyde and Methanol
products
249,650
Lbs./year
Formaldehyde and Phenol products
3,670,936
Lbs./year
Aniline Products
412,000
Lbs./year
Sulfochloronation products
1,300,000
Lbs./year
Simple mixes (no chemical reaction)
products
13,365,585
Lbs./year
Finished Dyes
6,214,000
Lbs./year
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.150 MGD
x Continuous
7 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Canteen Vending Services
Street address 4808 Chesapeake Drive
City Charlotte
State NC
Telephone Number
Fax Number
e-mail address
County Mecklenburg
Zip Code 28216
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Food Products
Raw and Cooked food products.
100000 units per
week
Sandwiches of
other food items
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.033 MGD
x Continuous
9 of 37

` NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Carolina Foods, Inc.
Street address 1807 South Tryon St..
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
Zip Code 28203
[phone]
N/A
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Pastries, Doughnuts and Pies
Sugar, flour, yeast, colorings, flavorings, fruit
fillings, water
35,000,000
Ibs/year
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.040 MGD
x Continuous .
10 of 37

• NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
,, Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Charlotte Pipe and Foundry
Street address 1335 South Clarkson Street
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Cast iron soil pipe and fittings
Scrap iron and steel
70
Tons/hr
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.500 MGD
x Continuous
11 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section ill for each Significant industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Chematron, Inc.
Street address 5210 and 5216 Hovis Road
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Binders and sizing agents
Water, caustic soda 50%, , latex 35%, muriatic acid, urea,
dowicide A, polyester resin, propylene oxide, corn starch,
hydrogen, peroxide 35%, phosphoric add 75%, sodium acetate
520 batch size
21279 Ibs
Batch/year
Scouring & wetting agents
Water, phosphoric anhydride, caustic soda 50%, isopropyl
alcohol, DA-6, NP-9, NP 4
365 batch size
1969 Ibs
Batch/year
Softeners
Butyl poultry, softener base, polyethylene, emulsion, silicone, co-
36, isopropyl alcohol
365 batch size
6675 Ibs
Batch/year
Lubricants
Water, sufonated castor oil, butyl stearate, urea, butyl poultry, co-
36, NP-4
365 batch size
16,820 Ibs
Batch/year
Defoamers
Mineral oil, ethylene, bis steramide, PEG 600 DT, GMS 140
solvent, silicone defoamer base
365 batch size
5195 Ibs
Batch/year
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.015 MGD
x Continuous
12 of 37

• NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION I11. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Chesapeake Treatment Company, LLC
Street address 4847 Chesapeake Dr.
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address
Zip Code 28216
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Soft Drink Bottling
Com syrup, flavorings, sugar, colors, carbonated
water
100,000
Cases/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.500 MGD x Continuous
13 of 37

• NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 1I1. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU CHEMCENTRAL / Charlotte
Street address 5010 Hovis Road
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material (This facility is a chemical repackager. They do not manufacture any products)
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Chemical Repackaged
Raw Material
Quantity
Units
Alcohols
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Esters
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Glycol Ether Ester
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Keytones
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Glycols
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Glycol Ethers
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Plasticizers
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Surfactants
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Acids
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Amines
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Alkalais
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Oleo Chemical
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Chelates
Dependent upon customer demand
55 gallon drum or 300 gallon totes
Water treatment chemicals
Dependent upon customer demand
55 gallon drum or 300 gallon totes
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.010 MGD
X Intermittent
14 of 37

.
NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Fleet Operations, Inc. d.b.a. Charlotte Tank Wash
Street address 201 Black Satchel Road
City Charlotte County Mecklenburg
State NC Zip Code 28216
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Internal and extemal cleaning of
tanker trucks.
Detergents and sodium hydroxide
32
Tankers/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.009 MGD
x Continuous
15 of 37

• NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Ecosolve , LLC
Street address 620 N. 1-85 Service Road
City Charlotte County Mecklenburg
State NC Zip Code 28216
Telephone Number [phone]
Fax Number [phone]
e-mail address ralphrAecologicalservices.com
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Grease Trap Pumping (cleaning)
150
Per month
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.008 MGD
X Intermittent
16 of 37

• NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION I11. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Fleming Laboratories, Inc.
Street address 2205 and 2215 Thrift Road
City Charlotte
State NC
Telephone Number
Fax Number
e-mail address
County Mecklenburg
Zip Code 28208
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Arsanilic Acid
Aniline, 75% Aqueous Arsenic Acid, Xylene
1100
Pounds
Piperazine Dihydrochloride
.68% Aqueous Piperazine, Concentrated
Hydrochloric Acid
1800
Pounds
34% w/v Dipiperazine Sulfate
.68% Aqueous Piperazine, Concentrated
Sulfuric Acid
1000
Gallons
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.011 MGD
X Continuous
17 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
. Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Heritage Environmental Services, LLC
Street address 4132 Pompano Road
City Charlotte County Mecklenburg
State NC Zip Code 28216
Telephone Number
Fax Number
e-mail address
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
CWT facility (Commercial resource
recovery and treatment facility)
48,000
Gals/day
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.019 MGD
X Intermittent
18 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Independent Beverage Corporation
Street address 3936 Corporation Circle
City Charlotte County Mecklenburg
State NC Zip Code 28216
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Soft Drink Bottling
Com syrup, flavorings, sugar, colors, carbonated
water
441,000
Cases/week
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.110 MGD
x Continuous
19 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
. Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Interstate Brands Corporation
Street address 301 South Interstate 85 P.O. Box 668648
City Charlotte County Mecklenburg
State NC Zip Code 28266
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Bread, rolls, English Muffins, brown &
serve rolls, donuts, and honeybuns.
Wheat flour, cream yeast, soy bean oil, salt
IBC 6Q0, Vital wheat gluten, amidan, yeast
food, Panodan, Pan Grease, Bromalain, IBRO,
Water, Paniplex SK, Fructose, Calcium
Propionate, Potassium Bromate
2.75 Million
Pounds/week
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.062 M G D
X Continuous
X
20 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Krispy Kreme Doughnut Corporation
Street address 3401 Wilkinson Boulevard
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address
Zip Code 28208
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Sweet Goods, Snack Items,
Doughnuts, Fried Pies, and Honey
Buns
Flour, Sugar, Shortening, and Fruit Fillings
40000 items
Individual snack
items
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.015 MGD x Continuous
21 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Pan-Glo Charlotte
Street address 3400 Pelton Road
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address
Zip Code 28220
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Clean and Recoat used commercial
baking pans: Deglaze solution
Hexyiene Glycol, Diethylene glycol, Potassium
Hydroxide
1200 to 2500 in a
18 to 30 hour
period
Baking pans
Soak Solution
Hi -Teeter Soap, Caustic Soap, Sodium Silicate,
Soda Ash, Polyerg Liquid (Surfactant)
Bleach Solution
Neutralization Tank
Sodium Hypochloride
Duodecyl Benzene Sulfonic Acid
Silicone Release Coating
Composition
Resin 21%-Toluene 14%
Light Aliphatic Naptha 39%
Isobutylisbutyrate 13%
Propylene Glycol Monobutyl Ether 13%
Coating Dilution Solvent
Composition
Ethylene Glycol Monobuytyl Ether 19%
Light Aliphatic Naptha 62%
Toluene 19%
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.022 MGD x Continuous
24 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 11! for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Pneumafil Corporation
Street address 4500 Chesapeake Dr.
City Charlotte
State NC
Telephone Number
Fax Number
e-mail address
County Mecklenburg
Zip Code 28216
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Cabinets/Electronic enclosures
Steel and aluminum sheet, castings and
forgings
250
Cabinets/year
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.018 MGD x Continuous
25 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Qualex, Incorporated
Street address 2511-2527 Distribution Street
City Charlotte County Mecklenburg
State NC Zip Code 28203
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Process photographic film to produce
prints and enlargements
Kodak Flexicolor process Chemicals, Kodak
Ektacolor RA chemicals
38000 in a 24 hour
period
Customers
orders
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.100 MGD
x Continuous
26 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section Ill for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Southern Aluminum Finishing Company
Street address 2322 Dunavant Street
City Charlotte County Mecklenburg
State NC Zip Code 28203
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Anodized Aluminum
Tin sulfate, sulfuric acid, sodium hydroxide,
nickel, novox 405
48 loads a day at
maximum
Small parts 1
inch to 28 feet
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.012 MGD x Continuous
27 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Stork Screens America
Street address 3001 North 1-85
City Charlotte County Mecklenburg
State NC Zip Code 28269
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Electroformed nickel screens
Nickel pellets, sulfuric acid
125,000
Units/year
Electroformed nickel sleeves
Nickel pellets, sulfuric acid
29,520
Units/year
Welded, engraved rotary printing
screens
Electroformed nickel screens,
photographic emulsion
3,500
Units/year
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.041 MGD
X Continuous
28 of 37

.
NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Textilease Corporation
Street address 4700 Dwight Evens Road
City Charlotte County Mecklenburg
State NC Zip Code 28217
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Laundry for rented clothes, mats,
wipers
Detergents
233000
Pounds per week
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.078 MGD
x Continuous
29 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows >1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU US Airways —Maintenance Facility
Street address 5535 Wilkinson Boulevard
City Charlotte County Mecklenburg
State NC Zip Code 28208
Telephone Number [phone]
Fax Number [phone]
e-mail address N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Servicing aircraft components:
cleaning, disassembly, inspection,
repair and reassembling of aircraft
parts.
Cleaning and degreasing chemicals, lubricants,
coatings, epoxy adhesives, sheet metal finishing
20 flap wings
25 engines
Monthly
20,000 wheel/tire
assemblies
Yearly
100 engine
cowling
Monthly
20 aircraft
lavatories
Monthly
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.026 MGD
X Continuous
31 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
SECTION 111. INDUSTRIAL WASTE CONTRIBUTION TO MUNICIPAL SYSTEM
Submit a separate Section 111 for each Significant Industrial User.
1. Significant Industrial User (SIU)
An SIU has (or could have) significant impact on the POTW receiving the wastewater or upon the quality of effluent from the receiving POTW.
Specifically, an SIU:
• has a flow of 50,000 gallons or more per average workday;
• has a flow greater than 5 percent of the total flow carried by the municipal system m receiving the waste, or
• has a toxic material in its discharge.
It may be necessary to alter these administrative criteria in certain cases, such as an instance where two or more contributing industries in
combination can produce an undesirable effect on either the municipal facility or the quality of its effluent.
Name of SIU Weyerhaeuser Company
Street address 5419 Hovis Road
City Charlotte County Mecklenburg
State NC
Telephone Number
Fax Number
e-mail address
Zip Code 28208
[phone]
[phone]
N/A
2. Primary Product or Raw Material
Specify either the principal product or the principal raw material and the maximum quantity per day produced or
consumed.
Quantities are to be reported in the units of measurement for each SIC category at the facility. SIC categories
should use the units of measurement normally used by that industry.
Product
Raw Material
Quantity
Units
Corrugated Shipping Containers
Kraft Paper, Com Starch, Flexo Ink, Resin,
Caustic Soda, Borax, Glue.
4.0 million sq ftlday
3. Flow
Indicate the volume of water discharged into the POTW and whether this discharge is intermittent or
continuous
0.0145 MGD
x Continuous
32 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
Attachment A — one of three pages
Irwin Creek Wastewater Treatment Plant — NPDES Permit #NC0024945
Present Operating Status
The Irwin Creek WUVTP is currently permitted at 15.0 MGD and treats a daily average flow of 9.77 MGD in
calendar year 2000. The facilities used to treat this flow consist of the following components.
Influent Barscreens (2) are manufactured by Infilco, with a width of 5', an opening of 3/8", and a length of 32'.
Each screen has a rated hydraulic capacity of 30 MGD.
Influent Centrifugal Lift Pumps (6). Pumps #1 & #2 are constant speed 40 HP units with a rated flow of 1,400
gpm. Pumps #3 & #4 are variable speed units (50 HP and 60 HP respectively) with rated flows of 3,970 and
5,070 gpm respectively. Pumps #5 & #6 are constant speed units (75 HP and 100 HP respectively) with rated
flows of 6,600 and 10,000 gpm respectively.
A Storm Event Flow Equalization System that will handle very high flows due to rain events is currently under
construction. This system is scheduled to be completed in April 2001 and is included with the present operating
status, since the facility will be completed before the current permit expires. The system is computer controlled.
The system will consist of a set of Storm Event Control Gates which divert excess flow to the Storm Event Pump
Station, the Storm Event Pump Station will have two climber Barscreens, screenings compactors, four 20 MGD
variable speed submersible pumps, a gravity type grit removal system, and two retention basins with a total
volume of 35 MG.
Grit Removal System consisting of 2 vortex type Smith & Lovelace settling units, each with a peak capacity of 30
MGD, 3 grit slurry pumps, each with a capacity of 250 gpm, 2 grits concentrator/dewaterers, and a conveyor belt to
transport the grit to a dumpster for final disposal.
Influent Plant Flow is monitored with 2 Parshall Flumes, each 3 ft. in diameter and a maximum flow capacity of 33
MGD.
Primary Clarification with 3 circular clarifiers, each 125 ft. in diameter with a side wall depth of 13'-10". Thickened
primary sludge is pumped to the digesters with 2 Dorr-Oliver air operated diaphragm pumps, each with a maximum
capacity of 70 gpm.
Intermediate Centrifugal Lift Pumps (6) lift water to the Trickling Filters. Pumps #1 & #2 are 75 HP units with rated
flows of 6,600 gpm. Pump #3 is a 25 HP unit with a rated capacity of 2,100 gpm. Pump #4 is a 60 HP unit with a
rated capacity of 5,070 gpm. Pump #5 is a 40 HP unit with a rated capacity of 2,800 gpm. Pump #6 is a 75 HP
unit with a rated capacity of 6,600 gpm.
Trickling Filters (4) each have a diameter of 100 ft. and a media depth of 6 ft. Two of the filters have granite media
and two have random plastic media.
Sodium hydroxide (NaOH) is stored in two (2) 3,000 gallon fiberglass tanks at either 25% or 50% concentration,
depending on season. NaOH is pumped into the Mixed Liquor prior to distribution to the individual basins for pH
control. Metering is achieved using 2 variable speed Pulsafeeder pumps, each with a maximum capacity of 21
gallons per hour.
33 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows >1 MGD or with pretreatment programs
Attachment A — two of three pages
Irwin Creek Wastewater Treatment Plant — NPDES Permit #NC0024945
Present Operating Status
Activated Sludge Aeration Basins (11) with a total volume of 6.1 MG are operated in parallel plug flow. Aeration
and mixing is provided by 4 compressors. Compressor #1 is a 600 HP Turblex single stage blower with a rated
maximum capacity of 15,000 scfm. Blowers #2. #3, & #4 are 450 HP multi -stage blowers with a rated capacity of
15,000 scfm. Air distribution is accomplished with circular membrane fine bubble diffusers manufactured by
Sanitaire. There are between 680 and 1080 diffusers in each basin, depending on the size of the basin.
Final Clarification with 3 circular clarifiers, each 125 ft. in diameter with a 14'-4" side wall depth. Scum is removed
with ducking skimmers and rotating scum trough. Return Activated Sludge (RAS) is pumped with 4 variable speed
centrifugal pumps, each a 50 HP unit rated at 4,900 gpm. Waste Activated Sludge (WAS) is pumped with 3
variable speed centrifugal pumps, each a 15 HP unit, rated at 375 gpm. In both the RAS and WAS Systems, flow
is monitored with magnetic flow meters.
Effluent Chlorination is achieved using compressed elemental chlorine. Six 1-ton tanks are maintained on scales,
feeding 2 Wallace-Tieman chlorinators. Each chlorinator has a maximum capacity of 1,000 pounds/day. Chlorine
application rate is controlled through the use of Stranco ORP controllers. Chlorine is mixed with the Secondary
Effluent in a pair of serpentine chlorine contact chambers, each with a capacity of 100,000 gallons. Additional
contact time is achieved in the Chlorine Detention Basin, a 120,000 gallon tank which also serves as the Effluent
Pump Wet Well.
Effluent Pumps (4) pump the plant flow up into the Effluent Tertiary Filters. Each pump is a 100 HP unit
manufactured by Layne & Bowler with a capacity of 7,300 gpm.
Effluent Tertiary Filters, 10 cells, each with a width of 12 ft., a length of 21 ft. and an anthracite monomedia depth
of 4 ft. Filtration and backwashing is computer controlled, with manual override available. Each cell has a rated
capacity of 3.7 gallft.2lday.
Dechlorination is achieved by injecting sodium bisulfite (SBS) at the effluent weir of the Effluent Teritary Filter. SBS
is stored as a 38 % concentrate in a 6,500 gallon fiberglass storage tank and pumped to the injection point by 2
Pulsafeeder diaphragm pumps. The pumps are variable speed, with a maximum capacity of 21 gpm. The SBS
pumps are controlled by a Stranco ORP controller.
Effluent flows are monitored with a magnetic flow meter between the Effluent Filters and the Cascade Aerator.
Final Aeration of the effluent is achieved in the Cascade Aerator. It consists of 5 steps, each 35 ft. wide with a 3 ft.
fall to the next step.
34 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
Attachment A — three of three pages
Irwin Creek Wastewater Treatment Plant — NPDES Permit #NC0024945
Present Operating Status
Waste Activated Sludge is pumped to a 300,000 gallon storage tank prior to thickening. The stored WAS is kept
aerated and mixed using 2 variable speed 60 HP positive displacement lobe type compressors manufactured by
Universal Blower Pac. Two variable speed progressive cavity type pumps manufactured by Netsch, pump the
sludge to the thickening process. Each is a 25 HP unit with a maximum capacity of 375 gpm. Two Ashbrook 1.5
meter Gravity Belt Thickeners (GBT) are used to thicken the WAS to approximately 5% total solids, which is
pumped to the digesters with 2 variable speed progressive cavity pumps, each a 10 HP unit with a maximum
capacity of 75 gpm. Bulk polymer is stored in tote bins, diluted to approximately 0.25% and stored in 2 fiberglass
storage tanks, each with a capacity of 3,900 gallons. Polymer is fed to the GBT with variable speed Pulsafeeder
diaphragm pumps.
Digestion is achieved using 4 fixed cover anaerobic digesters. Each digester is 65 ft. in diameter, 26'-3" deep, with
a total volume of 550,000 gallons each. Each of these digesters is mixed using a Lightnin' mechanical mixer.
These units are 20 HP and have two 4-blade propellers. Each of these digesters is heated using hot water from 2
gas burning boilers manufactured by Kewaunee. Each boiler has a capacity of 3,350 BTH and can bum either
digester gas or natural gas. Each digester has dedicated spiral type heat exchanger, manufactured by Alfa -Laval.
Digester gas is collected and scrubbed of Hydrogen Sulfide in 2 scrubbers. Digested sludge and gas are stored in
2 floating cover gas holder tanks, 65 ft. in diameter and 26'-3" deep, with a capacity of 550,000 gallons, each. Two
constant speed progressive cavity pumps manufactured by Netsch pump the digested sludge to the Dewatering
Facility. Each pump is a 25 HP unit with a capacity of 250 gpm.
Digested sludge is stored in an open top storage tank, 125 ft. in diameter, 20 ft. deep, with a capacity of 1.8 million
gallons. Three variable speed centrifugal pumps, each with a maximum capacity of 210 gpm, are used to feed 2
Roediger Belt Presses. Each press is 2 meters in width. Dewatered sludge is conveyed by a truck for storage on a
covered pad. Synagro, Inc. is responsible for delivery of the dewatered sludge to final disposal.
35 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
Attachment B
Irwin Creek Wastewater Treatment Plant — NPDES Permit #NC0024945
Potential Facility Changes
Charlotte Mecklenburg Utilities has several projects that are planned. These are primarily improvements to existing
facilities.
Primary Clarifier Rehab and Pump Station
This project scope includes:
o Replacing the drives and arms on the Primary Clarifiers
o Rehab and Replacement of the Catwalks
o Replace Sludge Pumping System
o Rehab/Replace/reroute Piping
Dewatering Building Improvements
This project includes:
o Modifying the polymer Preparation systems
o Addition of a sludge hopper
o Add the dewatering building to the plant SCADA system
o Replace Conveyor
o Add a roll up door
o Addition of a third filter belt press
Disinfection Altematives
Options of disinfection alternatives (instead of chlorine) are currently being evaluated. Design of a new
disinfection process or chlorine scrubbers will begin within the next year.
Paw Creek by-pass
Currently wastewater generated in the Paw Creek and Long Creek Sub -Basins discharge to McAlpine Creek
WWTP. There is a current evaluation being made on this wastewater to determine if this discharge should be
diverted to Irwin Creek Basin. The evaluation is in its preliminary stages at this time, and it is not known which
alternative will be reached.
36 of 37

NC DENR / DWQ / NPDES PERMIT APPLICATION - STANDARD FORM A
Municipal Facilities with permitted flows > 1 MGD or with pretreatment programs
Attachment C
Irwin Creek Wastewater Treatment Plant — NPDES Permit #NC0024945
Description of Sludge Management Plan
Digestion is achieved using 4 fixed cover anaerobic digesters. Each digester is 65 ft. in diameter, 26'-3" deep, with
a total volume of 550,000 gallons, each. Each of these digesters is mixed using a Lightnin' mechanical mixer.
These units are 20 HP and have two 4-blade propellers. Each of these digesters is heated using hot water from 2
gas burning boilers manufactured by Kewaunee. Each boiler has a capacity of 3,350 BTH and can bum either
digester gas or natural gas. Each digester has dedicated spiral type heat exchanger, manufactured by Alfa -Laval.
Digester gas is collected and scrubbed of Hydrogen Sulfide in 2 scrubbers. Digested sludge and gas are stored in
2 floating cover gas holder tanks, 65 ft. in diameter and 26'-3" deep, with a capacity of 550,000 gallons, each. Two
constant speed progressive cavity pumps manufactured by Netsch pump the digested sludge to the Dewatering
Facility. Each pump is a 25 HP unit with a capacity of 250 gpm.
Digested sludge is stored in an open top storage tank, 125 ft. in diameter, 20 ft. deep, with a capacity of 1.8 million
gallons. Three variable speed centrifugal pumps, each with a maximum capacity of 210 gpm, are used to feed 2
Roediger Belt Presses. Each press is 2 meters in width. Dewatered sludge is conveyed by a truck for storage on a
covered pad.
To address the long term reuse/disposal requirements for the residuals produced at all of our wastewater and
water treatment plants, Utilities conducted an industry wide, experience and qualifications based procurement
process to select a firm that could provide the needed services. A ten year contract was established effective July
1,1999, that provides for guaranteed beneficial reuse / disposal for all of the residuals produced during the term of
the agreement. The selected firm, Synagro, will use a combination of land application and lime stabilization. They
also have the option of composting for beneficial reuse. In the event that these options should become unfeasible
and/or unavailable, the firm has committed to landfill disposal. The contract establishes a pricing structure for the
entire term for all options. The contractor is responsible for determining what option will be utilized. Corporate
guarantors as well as a performance bond secure the contract.
Utilities has provided substantial sludge storage facilities at Irwin Creek WWTP. The contractor is required to
manage and maintain this facility. The management requirements include a guarantee that there is always a
minimum amount of space (typically 25% of the total floor space) open for Utilities' staff to deposit dewatered
biosolids cake. Utilities is responsible for putting the biosolids into the storage facility. The contractor is
responsible for managing the material in storage and for removal of the material to its final disposition. The
contractor has the option to store material from any of the plants with in the storage space provided.
The contractor is also required to identify and obtain permits for all required land application sites and/or other
reuse/disposal alternatives.
37 of 37

10 MGD /////
Attachment D
Irwin Creek WWTP, NPDES Permit #NC0024945 - Schematic Flow Diagram
Influent Pumps - 6
Influent Barscreens - 2
Land
Application 1
Creek
Grit to Disposal
Effluent
Flow Meter
Cascade
Aeration
4-0
Grit
Removal
Influent
Flow Meter
0.1 MGD
Belt Press
Dewatering
Equalization
Anaerobic
Digestion
4 Active
2 Gas Holding
0.16 MGD 1 Storage
Dechlorination
Tertiary Filters - 10
0.1 MGD
Primary
Clarifiers - 3
0.14 MGD
Primary
Sludge
Pumps - 2
0.02 MGD
Intermediate
Pumping - 6
PA/AS
Pumping-2
Effluent
Filter
Pumping - 4
0.15 MGD
Chlorination
WAS
Pumping - 3
Secondary
Clarifiers
Trickling Filters - 4
WAS 0.13 MGD
Thickening
Aeration
Blowers - 4
Activated Sludge - 11
7 MGD
RAS Pumps - 4
Filter Backwash

February 22, 2000
Note to File
Subject Sites:
Sugar Creek WWTP
Irwin Creek WWTP
McAlpine Creek WWTP
Mallard Creek WWTP
McDowell Creek WWTP
NPDES PERMIT NC0024937
NPDES PERMIT NC0024945
NPDES PERMIT NC0024970
NPDES PERMIT NC0030210
NPDES PERMIT NC0036277
RE: Application of lh FAV Calculation to the Subject
Sites
Joe has revised Maximum Daily Load effluent limits for only those parameters where
values increased (i.e. became less stringent) applying the latest'/a FAV calculations (see
Sue Wilson's memo dated January 2, 2000). Because this was "a minor mod at the
request of the permittee for revision of cyanide only," parameter values that would have
become more stringent, were not upgraded (per Dave Goodrich).
Therefore upon renewal of these permits, the next permit writer must
upgrade the other Daily Maximum parameters to the latest calculations.
Joe Corporon
NPDES Unit
cc. to each subject permit file