NC0024970_Permit Modification_19980615

NPDES DOCUHENT SCANNING COVER SHEET
NC0024970
McAlpine Creek WWTP
NPDES Permit:
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
e,:i1)2,21ttModification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
Meeting Notes
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
June 15, 1998
Thine document ios printed orz reuse paper -ignore a.riy
coritent on the reirerece e�ide

State of North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
Mr. Barry Gullet, Deputy Director
Charlotte -Mecklenburg Utility Department
5100 Brookshire Boulevard
Charlotte, North Carolina 28216
DENR
June 15, 1998
Subject:NPDES Permits Modifications
Permit No. NC0024937 Sugar Creek WWTP
Permit No. NC0024945 Irwin Creek WWTP
Permit No. NC0024970 McAlpine Creek WWTP
Permit No. NC0030210 Mallard Creek WWTP
Mecklenburg County
Dear Mr. Gullet:
The Division of Water Quality received your request for permit modifications on June 1, 1998 for
the above referenced facilities. The permits have been modified per your written request for NPDES
permit modification and modification fee (check #634351, $300). Three minor corrections were also
made to Permit No. NC0030210. The following are the listed changes made to each permit:
Permit No. NC0024937, Sugar Creek WWTP
• The daily maximum requirement for Total Residual Chlorine was changed to a daily average
requirement of 28 µg/1 with a weekly average of 19 µg/1.
Permit No. NC0024945, Irwin Creek WWTP
• The daily maximum requirement for Total Residual Chlorine was chanced to a daily average
requirement of 28 µg/1 with a weekly average of 21 µg/l.
Permit No. NC0024970, McAlpine Creek WWTP
• The daily maximum requirement for Total Residual Chlorine was changed to a daily average
requirement of 28 µg/1 with a weekly average of 17 µg/1.
• The Chronic Toxicity (Ceriodaphnia) P/F at 90% test was changed to a Chronic Toxicity (Phase
II) at 90% test. As was stated on the permit issuance letter for NC0030210, dated April 27, 1998,
"If the test procedure performed as the first test of any single quarter measures 48-hour acute
toxicity or a chronic value less than that specified above, then multiple concentration testing shall
be performed, at a minimum, in each of the two following months." If the facility performs a
quarterly single concentration test at 90% that fails, multiple concentration tests must be run in
the consecutive months of the quarter and the arithmetic average of values will be used to
determine if the chronic limit is met.
Permit No. NC0030210, Mallard Creek WWTP
• The following statement was mistakenly added to the permit issuance letter, dated April 27,
1998. "Added weekly Chromium testing, limited at 53.0 µg/1." Monitoring only is required for
Chromium.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled/ 10% post -consumer paper

NPDES Permit Modifications
Charlotte -Mecklenburg Utility Department
June 15, 1998
Page 2
• The following language was added as footnote 6 to effluent pages A., B., and C. The detection
limit for mercury is 0.2 µg/I. If the measured levels of mercury are below the detection limit,
then the measurement is considered to be zero for purposes of compliance evaluation and should
be reported on the DMR as < 0.2
• Conductivity measurement was inadvertently added to the outfall 001 effluent discharge. This
has been removed.
• Total Residual Chlorine monitoring was inadvertently removed from the outfall 002 effluent
discharge. It has been added back, although it is still only required if chlorine disinfection is
used.
Please find enclosed amended effluent sheets which should be inserted into the respective
permits. The old effluent pages should be discarded. All other terms and conditions contained in the
original permit remain unchanged and in full effect. This permit modification is issued pursuant to the
requirements of North Carolina General Statutes 143-215.1 and the Memorandum of Agreement
between North Carolina and the U. S. Environmental Protection Agency.
If any parts, measurement frequencies or sampling requirements contained in this permit
modification 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, Post Office Drawer 27447, Raleigh, North Carolina 27611-7447. Unless such
a demand is made, this permit modification shall be final and binding.
If you have any questions, please contact Mary Cabe of my staff at [phone], extension 518.
Sincerely,
Fiw(ft-(:"A--
tfr Preston Howard, Jr., P.E.
Attachments
cc: NPDES Unit
Point Source Compliance / Enforcement Unit
Central Files
Mooresville Regional Office, Water Quality Section
Technical Assistance & Certification Unit
Aquatic Toxicology Unit
Mr. J. Reed Atkinson / CMUD

A. (1). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
Permit No. NC0024970
During the period beginning on the effective date of the permit and lasting until EXPANSION ABOVE 48.0 MGD, the Permittee is
authorized to discharge from outfall(s) serial number 001. Such discharges shall be limited and monitored by the Permittee as specified
below:
Effluent Characteristics
Flow
CBOD, 5-Day, 20°C 2 (April 1 - Oct. 31)
CBOD, 5-Day, 20°C 2 (Nov. 1 - March 3
Total Suspended Residue 2
NH3 as N (April 1 - October 31)
NH3 as N (November 1 - March 31)
Dissolved Oxygen 3
Fecal Coliform (geometric mean)
Total Residual Chlorine
Temperature
Total Nitrogen (NO2 + NO3 + TKN)
Total Phosphorus
Chronic Toxicity 4
Conductivity
Discharge Limitations
Monthly Avg. Weekly Avg.
48.0 MGD
4.0 mg/1 6.0 mg/1
1) 8.0 mg/1 12.0 mg/1
15.0 mg/1 22.5 mg/1
1.0 mg/1
1.9 mg/1
200/100 ml 400/100 ml
17.0 vigil
Daily Avg. Frequency
Continuous
Daily
Daily
Daily
Daily
Daily
Daily
Daily
28.0 µg/1 Daily
Daily
Monthly
Monthly
Quarterly
Daily
Monitoring Requirements
Measurement Sample
Type
Recording
Sample
Location
I or E
Composite E, I
Composite E, I
Composite E, I
Composite E
Composite E
Grab E, U, D
Grab E
Grab E
Grab E, U, D
Composite E
Composite E
Composite E
Grab
Footnotes:
Sample locations: E - Effluent, I - Influent, U - Upstream, D - Downstream. For instream monitoring requirements, see Part III, Condition G.
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/1.
4 Chronic Toxicity (Phase II) at 90%. Samples shall be taken quarterly during the months of March, June, September and December; See Part III,
Condition H.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units and shall be collected at the effluent daily by grab sample.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (2). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
lasting until EXPANSION ABOVE 48.0 MGD (Continued)
Permit No. NC0024970
Effluent Characteristics
Cadmium
Chromium
Nickel
Lindane
Copper
Cyanide
Lead
Silver
Zinc
Discharge Limitations
Monthly Avg. Weekly Avg. Daily
2.0 µg/1 5.0
51.0 µg/1 204.0
90.0 µg/1 360.0
5.0 µg/1
26.0 µg/1
34.0
Measurement
Frequency
Weekly
Weekly
Weekly
2/month
2/month
Weekly
Weekly
2/month
2/month
Monitoring Requirements
Sample Sample
Type / Location t
Composite) E, U, D
Composite E
Composite E
Grab E
Composite E, U, D
Grab E
Composite E
Composite E
Composite E, U, D
Footnotes:
1 Sample locations: E - Effluent, I - Influent, U - Upstream, D - Downstream. For instream monitoring requirements, see Part III, Condition G.
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/1.
4 Chronic Toxicity (Phase II) at 90%. Samples shall be taken quarterly during the months of March, June, September and December; See Part III,
Condition H.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units and shall be collected at the effluent daily by grab sample.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (1). LI'FLUENT i1Mf1A1IONS ru'L 1vioNfl ING REQUiIU MENTS
Permii No.1v 0024970
During the period beginning upon EXPANSION ABOVE 48.0 MGD and lasting until expiration, the Permittee is authorized to
discharge from outfall(s) serial number 001. Such discharges shall be limited and monitored by the Permittee as specified below:
Effluent Characteristics
Flow
CBOD, 5-Day, 20°C 2 (April 1 - Oct. 31)
CBOD, 5-Day, 20°C 2 (Nov. 1 - March 31)
Total Suspended Residue 2
NH3 as N (April 1 - October 31)
NH3 as N (November 1 - March 31)
Dissolved Oxygen 3
Fecal Coliform (geometric mean)
Total Residual Chlorine
Temperature
Total Nitrogen (NO2 + NO3 + TKN)
Total Phosphorus
Chronic Toxicity 4
Conductivity
Discharge Limitations .Monitoring Requirements
Measurement Sample Sample
Monthly Avg. Weekly Avg. Daily Avg. Frequency Type Location 1
64.0 MGD
4.0 mg/1 6.0 mg/1
8.0 mg/1 12.0 mg/I
15.0 mg/1 22.5 mg/1
1.0 mg/1
1.9 mg/I
200/100 ml
400/100 ml
17.0 µg/1
28.0 µg/1
Continuous Recording I or E
Daily Composite E, I
Daily Composite E, I
Daily Composite E, I
Daily Composite E
Daily Composite E
Daily Grab E, U, D
Daily Grab E
Daily Grab E
Daily Grab E, U, D
Monthly Composite E
Monthly Composite E
Quarterly Composite E
Daily Grab E, U, D
Footnotes:
1 Sample locations: E - Effluent, I - Influent, U - Upstream, D - Downstream. For instream monitoring requirements, see Part III, Condition G.
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 Chronic Toxicity (Phase II) at 90%. Samples shall be taken quarterly during the months of March, June, September and December; See Part III,
Condition H.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units and shall be collected at the effluent daily by grab sample.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (2). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
beginning upon EXPANSION ABOVE 48.0 MGD and lasting until expiration (Continued)
Permit No. NC0024970
Effluent Characteristics
Cadmium
Chromium
Nickel
Lindane
Copper
Cyanide
Lead
Silver
Zinc
Footnotes:
I Sample locations: E - Effluent, I - Influent, U - Upstream, D - Downstream. For instream monitoring requirements, see Part III, Condition G.
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/1.
4 Chronic Toxicity (Phase II) at 90%. Samples shall be taken quarterly during the months of March, June, September and December; See Part III,
Condition H.
Discharge Limitations
Monitorin
Monthly Avg. Weekly Avg. Daily Max.
2.0 µg/1 5.0 µg/I Weekly
51.0 µg/1 204.0 µg/l Weekly
90.0 µg/1 360.0 i_tg/1 Weekly
5.0 µg/1
26.0 µg/1
15.0 µg/1
34.0 µg/1
R��e u��irements
Measuremen 3Tample Sample
Frequency Type'
2/month
2/month
Weekly
Weekly
2/month
2/month
Location I
Composite E, U, D
Composite E
Composite E
Grab E
Composite E, U, D
Grab E
Composite E
Composite E
Composite E, U, D
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units and shall be collected at the effluent daily by grab sample.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Part III
Permit No. NC0024970
H. CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
The effluent discharge shall at no time exhibit 48 hour acute toxicity as lethality in an effluent
concentration of 90% nor measure a quarterly arithmetic average chronic value less than this same
percentage of waste. The chronic value 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 presence of 48 hour acute
toxicity will be determined using Fisher's Exact Test at 48 hours from test initiation. 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 -
November 1995) or subsequent versions.
The permit holder shall perform at a minimum, quarterly monitoring using these procedures to
establish compliance with the permit condition. The tests will be performed during the months of
March, June, September, and December. 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 measures 48 hour acute toxicity or
a chronic value less than that specified above, then multiple concentration testing shall be performed, at
a minimum, in each of the two following months.
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 THP3B for the Chronic Value and TGA3B for the 48 hour Acute Toxicity measure (Pass/Fail).
Additionally, DWQ Form AT-3 (original) is to be sent to the following address:
Attention: Environmental Sciences Branch
North Carolina Division of
Water Quality
4401 Reedy Creek Road
Raleigh, North Carolina 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. 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, then
monthly monitoring will begin immediately until such time that a single test is passed. Upon passing,
this monthly test requirement will revert to the schedule specified above.
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.

•
CHARLOTTE.
May 26, 1998
Mary Cabe
NC DENR, Div of Water Quality
P.O. Box 29535
Raleigh, North Carolina 27626-0535
. Subject: Minor Permit Modifications
McAlpine Creek NPDES Permit No. NC0024970
Sugar Creek NPDES Permit No. NC0024937
Irwin Creek NPDES Permit No. NC0024945
Dear Mary:
I am sending our check for $300.00 for minor modifications to the subject NPDES permits. This is per our
conversation last week and stems from our informational request in December 1997.
The first modif cation requested is to change the Total Residual Chlorine (TRC) limit in each of the three permits
above from a Daily Maximum to a Daily Average value. Specifically, each plant would have a maximum Daily
Average concentration limit of 28ug/l. Sampling would be by the "grab" method, with one or more samples collected
daily.
The second modification requested is to change the toxicity testing requirement from the Chronic Toxicity
(Ceriodaphnia) P/F test to the Chronic Toxicity Phase II test at McAlpine Creek only. We request that the Phase II
toxicity test language that is in the recently issued Mallard Creek NPDES permit be used, including an explanation as
in the Mallard Creek permit cover letter that explains that compliance is determined either by passing the quarterly
test, or by passing on the basis of a quarterly arithmetic average of subsequent test values.
Please let me know if you have any questions or need additional information. Thank you for your assistance.
Sincerely,
CHARLOTTE MECKLENBURG UTILITIES
Ct) C,)42r
Barry M. ullet, PE
Deputy Director
cc: Kim Neely, McAlpine Creek ORC
Tom Hunter, Irwin Creek ORC •
Roy Purgason, Sugar Creek ORC
Myra Zabec, Lab Manager
File
Administration Division 5100 Brookshire Boulevard Charlotte, NC 28216 704/399-2221
Charlotte -Mecklenburg Utility Department

CMUD - TRC daily avg limit
•
Subject: CMUD - TRC daily avg limit
Date: Wed, 20 May 1998 09:00:46 -0500
From: "Kevin Bowden"<[e-mail]>
To: [e-mail]
Mary, we looked at CMUD's request to have it's daily max TRC limit changed
to daily avg. We don't see any major setbacks as a result of this proposed
modification.
Kevin Bowden
NC DENR - Division of Water Quality
Aquatic Toxicology Unit
4401 Reedy Creek Road
Raleigh, NC 27607
phone: [phone]
fax: [phone]
e-mail: [e-mail]
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