NC0047384_Fact Sheet_20140606

NCDENR / DWQ
FACT SHEET
NPDES PERMIT RENEWAL AND EXPANSION
City of Greensboro/T.Z. Osborne WWTP
NPDES No. NC0047384
Facility Information
Facility Name:
T.Z. Osborne WWTP (South Buffalo Creek)
Permitted Flow, MGD:
40 mgd renewal and
expansion to 56 MGD
County:
Guilford
Facility Class:
4
Regional Office:
Winston Salem
Facility Status:
Existing
USGS Topo Quad:
C20SW
(McLeansville)
41
Permit Status:
Stream Characteristics
Renewal and Expansion
Receiving Stream:
South Buffalo Creek
Drainage Area (mi2):
Subbasin/ 8 Digit
HUC:
030602/03030002
Summer 7Q10 (cfs)
2.1
Index No.:
16-11-14-2C
Winter 7Q10 (cfs):
4.7
Stream Class:
WS-V, NSW
30Q2 (cfs):
6.5
303(d) Listed:
YES, for Cu and Zn
Average Flow (cfs):
46
Use Support:
Impaired
IWC (%) at 40 and 56 MGD:
96.7% / 97.6%
SUMMARY
This facility is a major municipal treatment plant operating in Guilford County. The City of Greensboro
operates the TZ Osborne WWTP and this permit application was originally submitted on Jan. 4, 2011 for
a permit renewal at the current plant design flow of 40 MGD. On Feb. 22, 2013 the City submitted a
revised renewal application to include an expansion modification from 40 MGD to 56 MGD. In addition,
on April 25, 2013 the City of Greensboro submitted data requesting monitoring frequency reductions for
fecal coliform, total suspended solids, CBOD5, and ammonia -nitrogen. Additional information was
requested and received on May 1, 2013. The permit was than redrafted but put on hold pending proposed
changes to the Jordan Lake rules in state legislation. In 2013 the Jordan Lake Wastewater Discharge Rule
was modified by Session Laws 2011-394 (HB119) and 2013-395 (SB515). This permit was then re-
drafted to include these modifications and a Total Nitrogen reduction schedule outlining the actions the
City will take to comply with annual total nitrogen targets listed in NPDES Permit NC0047384.
BACKGROUND
The City of Greensboro currently operates both the T. Z. Osborne WWTP with a permitted discharge of
40 MGD and the North Buffalo Creek WWTP with a permitted discharge of 16 MGD. As part of the B.
Everett Jordan Reservoir Nutrient Management Strategy and TMDL adopted in August 2009 the City of
Greensboro assessed alternatives for the two WWTP's to meet TMDL nutrient limitations. The most
feasible and cost effective alternative determined was to expand and upgrade the T.Z. Osborne WWTP to
a combined permitted discharge of 56 MGD and to rescind the NPDES permit for the North Buffalo
Creek WWTP.
In 2010, the City requested and received speculative limits for a combined discharge of 56 MGD from
the T.Z. Osborne facility to South Buffalo Creek. In February 2012, The City of Greensboro submitted a
SEPA Environmental Assessment on the proposed expansion and on October 9, 2012, a Finding of No
Significant Impact was issued. As stated above, the City than resubmitted its permit renewal application
which included the expansion to 56 MGD. The proposed project will not increase the total wastewater
treatment capacity for the City and the geographical service area will not be increased beyond the current
plannning limits.

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 2 NPDES No. NC0047384
For the past 3 years, the T.Z. Osborne WWTP has discharged an average flow of 23 MGD into South
Buffalo Creek. The City has a separate sewer collection system. The City of Greensboro has 34
Significant Industrial Users (SIUs) and a full-scale pretreatment program. SIUs include metal finishers
and electroplaters, organic chemical manufacturing, centralized waste treatment, electrical and electronic
component manufacturing, textile manufacturers, one tobacco company, and two pharmaceutical
companies. Twenty-nine SIUs discharge directly to the T.Z. Osborne WWTP and five SIUs send their
effluent to the North Buffalo Creek WWTP. A portion of the wastewaters received at the N. Buffalo
WWTP are currently diverted to the T.Z. Osborne WWTP and treated. In 2010, the total average daily
flow to the North Buffalo Creek WWTP was 15.4 MGD. Approximately 6 MGD was treated and
discharged to North Buffalo Creek, and 9.4 mgd was transferred to the T.Z. Osborne WWTP for
treatment and discharge.
The WWTPs, T.Z. Osborne and North Buffalo, ultimately discharge to the Haw River arm of Jordan Lake.
The T.Z. Osborne WWTP discharges to South Buffalo Creek, which then discharges to Buffalo
Creek>Reedy Fork>Haw River>Jordan Lake. South Buffalo Creek is an effluent -dominated stream, with
the Greensboro discharge representing 96.7% of the in -stream waste concentration (IWC) at 40 mgd and
97.6% IWC at 56 mgd. South Buffalo Creek is listed on the 2012 303(d) list for Cu and Zn impairments.
With the adoption of the Jordan Lake Nutrient Management Strategy and TMDL in Aug. 2009, the City
of Greenboro will have to control nitrogen to meet the following annual TN mass loadings:.
Jordan Lake Rules End -of -Pipe Target TN Annual Mass Loadings
Concentration
POTW
Permitted Flow
Annual Mass Load
North Buffalo
16.0 MGD
257,438 pounds
—5.3 mg/L
T.Z. Osborne
40.0 MGD
643,595 pounds
—5.3 mg/L
The permit was modified in 2010 to reflect the Jordan Lake Nutrient Management Strategy and TMDL
and this permit includes additional modifications made to the rule as modified by North Carolina Session
Laws 2011-394 (HB119) and 2013-395 (SB515). These modifications extend compliance with the TN
Combined Limit to 2019; however, if an ATC is acquired for purposes of complying with the allocation
prior to Dec. 31, 2019, the annual mass Total Nitrogen limit shall be effective beginning with calendar
year 2021.
As part of the Management Strategy, South Buffalo Creek was reclassified as a WS-V stream. The
closest downstream intake on the Haw River is the Town of Pittsboro's which is approximately 65 river
miles below the T.Z. Osborne outfall. On July 16, 2012 the NC Governor signed Senate Bill 810 which
included the following clarification on WS-V waters:
SECTION 12.1. Rules adopted by the Environmental Management Commission
pursuant to S.L. 2009-216 and S.L. 2009-486 to implement nutrient management strategies for
the B. Everett Jordan Reservoir and the Falls of the Neuse Reservoir watersheds shall not be
interpreted to apply surface water quality standards set out in 15A NCAC 2B .0218(3)(e)
through (3)(h) to waters designated in the nutrient management rules as WS-V except where:
(i) the designation of WS-V is associated with a water supply intake used by an industry to
supply drinking water for their employees; or (ii) standards set out in I5A NCAC 02B
.0218(3)(e) through (3)(h) are violated at the upstream boundary of waters within those
watersheds that are classified as WS-II, WS-III, or WS-IV. This section shall not be construed
to alter the nutrient reduction requirements set out in 15A NCAC 2B .0262(5) or 15A NCAC
2B .0275(3).
As a result, effluent sampling data for pollutants of concern were compared to Human Health standards
pertaining to organism consumption and Aquatic Life freshwater, Water Quality Standards (WQS).
Surface water quality standards found under 15A NCAC 2B .0218(3)(e) through (3) (h) were not applied.
Page 2
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 3 NPDES No. NC0047384
PERMIT LIMIT DEVELOPMENT
AMMONIA -NITROGEN
Note that the BOD ultimate loading at 40 MGD for the TZ Osborne WWTP was frozen to determine the
CBODS limits for the 56 MGD expansion. As a result, the ammonia -nitrogen limit was lowered to 0.82
mg/L as a summer monthly average and 1.64 mg/L as a winter monthly average at 56 MGD. TheX -e FP&eri I-
_4,teolitm DO stendard-is to be maintained at above 6 mg/L.
/I di
REASONABLE POTENTIAL ANALYSIS
Reasonable potential analyses were conducted for As, Cu, F, Pb, Ni, Se, and Zn (see RPA attached). All
other toxicants reported samples at levels below detection — Be, Cd, Cr, CN, and Ag.
Effluent sampling data for Arsenic, Fluoride, Lead, and Nickel showed no reasonable potential to violate
Water Quality Standards.
Effluent sampling data for Selenium, Copper and Zinc showed reasonable potential to violate Water
Quality Standards. Recommendations:
• Monthly monitoring and limitations for Selenium were added to the permit.
• Copper and Zinc are action level standards and are reviewed in conjunction with toxicity
testing. Copper and Zinc monitoring will remain in the permit at a reduced frequency of
quarterly. The City has passed 21 out of 22 Whole Effluent Toxicity Tests between 2009
and 2013. Copper and Zinc limitations are not considered necessary for this discharge.
All the metals will continue to be monitored as part of the City's Pretreatment Program.
MERCURY LIMITATION REVIEW:
Effluent Mercury Data — T.Z. Osborne
Year
2009
2010
2011
2012
2013
# of Samples
52
51
52
52
44
Annual Average, ng/L
6.2
5.4
3.8
3.9
3.7
Maximum Value, ng/L
13.60
19.70
11.10
11.90
9.30
TBEL, ng/L
47
WQBEL, ng/L
12.4
Per the Division guidelines for implementing the mercury TMDL, five years of mercury effluent data
was evaluated. Annual averages for all five years were less than the allowable Water Quality Based
Effluent Limitation of 12.4 ng/L and the Technology Based Effluent Limitation (TBEL) of 47 ng/L. In
accordance with the implementation of the 2012 Statewide Mercury TMDL, the City is required to
develop and implement a Mercury Minimization Plan and continue to monitor for mercury as part of its
Effluent Pollutant Scans.
TOXICITY TESTING:
Type of Toxicity Test:
Existing Limit:
Recommended Limit:
Monitoring Schedule:
Chronic P/F
001: Chronic P/F @ 90%
001: Chronic P/F @ 90%
January, April, July, and October
The facility has been consistently passing its WET tests. During the period from 2009 through 2013 it
has passed 21 out of 22 toxicity tests. Second species tests were performed and passed as well.
Page 3
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 4 NPDES No. NC0047384
COMPLIANCE SUMMARY:
DMRs have been reviewed for the period January 2009 through December 2013. The facility received
five Notices of Violation (NOVs) during that time period. The NOV's issued cited exceedances for the
following parameters during the months listed: Hg in 2/2009, Hg in 12/2009, Hg in 2/2010, ammonia -
nitrogen and CBOD5 in 4/2011, and CBOD5 in 7/2012. No permit limit violations occurred in 2013.
The last routine compliance evaluation inspection was conducted on March 12, 2012 and the facility
evaluation rating was extremely reliable. The last routine pretreatment compliance evaluation inspection
was conducted on August 24, 2012 and the facility evaluation rating was extremely reliable.
INSTREAM MONITORING:
Instream monitoring is required for temperature, dissolved oxygen, fecal conform, and conductivity. The
facility is a member of the Upper Cape Fear Monitoring Coalition, and all their instream monitoring is
conditionally waived for the duration of their membership in the Coalition.
The 2005 Cape Fear River Basin Plan recommends that the City of Greensboro continue to monitor water
quality on S. Buffalo Creek and continue to work with DWR to identify measures thatcan be used to
reduce stormwater impacts to the creek. In 2002, Greensboro received a $570,000 CWMTF grant to
construct a 20-acre stormwater wetland along South Buffalo Creek treating runoff from 13 square miles
of urban land.
All three segments of S. Buffalo Creek remain on the 2012 303(d) list showing aquatic life impairments.
TMDLs are expected to be developed for identified stressors within 8-13 years of listing.
NUTRIENTS:
TN and TP Limits: Total Nitrogen and Total Phosphorus limits were determined as part of the Jordan
Lake Nutrient Management Strategy which includes a Wastewater Discharge rule (T15A NCAC 02B
.0270) that established maximum loads of nitrogen and phosphorus that can be released from wastewater
treatment facilities into the Jordan Lake watershed. The rule specifies that the wasteload allocations are
to be divided among the existing facilities in proportion to their 2001 permitted flows (with certain
exceptions).
SEPA/FONSI DETERMINATION:
The proposed expansion was subject to review by governmental agencies under the State of North
Carolina Environmental Policy Act (SEPA EA), and DWR has concluded that the proposed project will
not result in significant impacts to the environment. A Finding of No Significant Impact (FONSI) was
issued on October 9, 2012 and is available for inspection at the State Clearinghouse.
ANTIDEGRADATION REVIEW:
Per NC Antidegradation Policy (15A NCAC 2B.0201), each applicant for an NPDES permit expansion
must document an effort to consider non -discharge alternatives pursuant to 15A NCAC 2H.0105(c)(2).
This alternatives evaluation was submitted as part of the SEPA EA document, and resubmitted with the
permit renewal and expansion. It is important to note that the proposed project will not increase the total
wastewater treatment capacity for the City and the geographical service area will not be increased beyond
the current plannning limits. DWR staff reviewed both the previous flow justification for the City's
service area as well as the alternatives analysis to meet the nutrient TMDL standards. DWR staff
concurred with the projected flow needs based on a 20-year planning horizon. The service area
population is expected to increase from 269,666 (in 2010) to 429,841 (in 2035). The main four
alternative discharge options considered and their corresponding comparative costs included:
1) Nutrient Removal Upgrades to existing surface water discharges — North Buffalo Creek and T.Z.
Osborne WWTPs at a 20-year Total Present Worth cost of $150,700,000
2) Land Application with a 60-day storage pond at a 20-year Total Present Worth cost of $573,700,000.
Page 4
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 5 NPDES No. NC0047384
3) Reuse Spray Irrigation using approximately 6,400 acres at a 20-year Total Present Worth cost of
$573,700,000.
4) Upgrades at T.Z. Osborne to treat 56 MGD and decommissioning the N. Buffalo Creek WWTP,
transferring all the City's permitted flow to one facility and complying with TMDL nutrient standards, at
a 20-year Total Present Worth cost of $133,200,000.
DWR concurred with the alternatives analysis conclusion that the upgrade and expansion of the T.Z.
Osborne facility(option number 4 above) with a direct discharge to South Buffalo Creek is the most
environmentally sound alternative from all reasonably cost-effective options (per 15A NCAC 2H.0105).
MONITORING FREQUENCY REDUCTION EVALUATION:
• On April 25, 2013 the City of Greensboro submitted data requesting monitoring frequency reductions
for fecal coliform, total suspended solids, CBOD5, and ammonia -nitrogen. Additional information
was requested and received on May 1, 2013. Three years of effluent data were reviewed (2011-2013)
for each parameter and a summary on the analysis is attached and titled - Effluent Analysis
Summary. Reduced monitoring frequencies for fecal coliform, total suspended solids, and CBOD5
were granted based on long-term treatment performance at levels consistently below effluent
limitations (<50%). Ammonia -nitrogen effluent sampling results did not meet the Guidance
requirements to allow for a sampling reduction.
PROPOSED CHANGES:
• . Change the permit expiration date to June 30, 2019 to allow five years before permit renewal.
• Reduce monitoring frequencies for fecal coliform, total suspended solids, and CBOD5 from daily
monitoring to twice per week.
• Cyanide, cadmium, nickel, and fluoride effluent sampling results did not show reasonable potential
to violate Water Quality Standards (WQS). Limits and monitoring requirements for all four
parameters were removed from the permit.
• Effluent sampling data for selenium showed reasonable potential to violate Water Quality Standards.
Monthly monitoring and limitations for selenium were added to the permit.
• Copper and zinc sampling results showed reasonable potential to violate WQS, however, they are
action level parameters and limits are set in conjuction with toxicity test results. T.Z. Osborne is
passing its toxicity tests so limits are not necessary. Both parameters remain in the permit and
sampling was reduced from monthly to quarterly in accordance with the NPDES Monitoring
Frequency memo dated July 15, 2010.
• Mercury annual averages were less than the WQBEL and the TBEL of 47 ng/L. In accordance with
the 2012 Statewide Mercury TMDL and NPDES Permitting Implementation the mercury limitation
was removed. The facility will be required to implement a Mercury Minimization Plan and continue
monitoring mercury as part of their Effluent Pollutant Scans.
• Section A.(2.) was added to include limitations and monitoring requirements when T.Z. Osborne
WWTP is expanded to 56 MGD. Changes in the Total Residual Chlorine and Selenium limitations
are based on the increased Instream Waste Concentration (IWC) at 56 MGD.
• Footnote #2 in Section A.(3.) was revised to recognize North Carolina Session Laws 2011-394
(HB119) and 2013-395 (SB515) which extends the compliance date to 2021 if an ATC is acquired
before Dec. 31, 2019 for upgrades needed to meet the TN allocation.
• In accordance with Federal Regulations 40 CFR 122 a schedule containing annual milestones
outlining the steps the City of Greensboro will take to comply with the Jordan Lake Wastewater
Discharge Rule (15A NCAC 02B .0270), as modified by North Carolina Session Laws 2011-394
(HB 119) and 2013-395 (SB515), was added under Special Condition A.(4.).
Page 5
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 6 NPDES No. NC0047384
• Section A. (6.) on the Effluent Pollutant Scan now designates the three years in which the scans are
to be performed.
• Sections A.(7.) and A.(9.) were revised to include TN and TP allocations and load calculation
changes when T.Z. Osborne is expanded to 56 mgd and N. Buffalo is closed.
• Section A. (10.) Nitrogen Optimization Plan was added to confirm that the City of Greensboro will
continue to evaluate its treatment facilities and operational processes to make reasonable efforts to
reduce nitrogen discharges until process improvements are completed as stated in its nitrogen
optimization plan dated 2/11/2010.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice: Feb. 12, 2014 (est.)
Permit Scheduled to Issue: April 7, 2014 (est.)
STATE CONTACT:
If you have any questions on any of the above information or on the attached permit, please contact Julie
Grzyb at [phone].
NAME:
REGIONAL COMMENTS:
No additional comments received from the Region.
EPA COMMENTS:
No comments received from EPA.
NC WRC COMMENTS:
DATE: of o
See attached memorandum dated 2-19-2014.
Comment 1. NC WRC was pleased to see that the ammonia -nitrogen speculative limits were included in
the permit. Comment 2. NC WRC recommends UV or ozone disinfection systems over chlorine contact
tanks due to aquatics toxicity caused by chlorine and associated compounds.
Page 6
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 7 NPDES No. NC0047384
Addendum to fact sheet 6-2-2014:
Below are the NPDES responses to the comments received from the City of Greensboro on their draft
permit dated March 21, 2014. The comments are briefly noted first with NPDES responses in italics. The
comment letter from the City is attached to the Fact Sheet.
1. The footnote documenting the City's authority to use 20 ug/L as the POTW's specific analytical
limit was removed from the permit. The City requested that the footnote be inserted back into
the effluent pages.
Cyanide effluent monitoring and limitations were removed since no reasonable potential was
shown for cyanide to violate state Water Quality Standards. Since the footnote would not
reference anything in the permit, the POTW's specific analytical limit for cyanide will be
recognized in the cover letter.
2. The City of Greensboro requested that the raw data used to determine the TN and TP
calculations in the permit be provided in the fact sheet.
An explanation of how the allocations were determined is provided below:
Calculation of combined nutrient limits for Greensboro WWTPs
The City has two WWTPs and N & P allocations for each. Two schools have also connected to the TZO
plant, and their allocations were transferred to TZO in accordance with the Jordan Lake WW rule.
A few key considerations in combining allocations to set limits
Nutrient reduction targets in the Jordan Lake strategy — the resulting nutrient limits in NPDES
wastewater permits — are ultimately concerned with controlling the amounts of nitrogen and
phosphorus delivered to the lake.
Some portion of the nitrogen and the phosphorus discharged upstream of the lake is lost in transit to
the lake. The amounts of nutrients lost increase with travel time. Transport factors are an estimate
of the losses and are used to convert nutrient loads, allocations, or limits from 'discharge' to
'delivered' values and back.
Transport factors in the Jordan Lake watersheds vary from one facility to the next. Thus, all transfers
of allocation must be conducted in terms of 'delivered' loads in order to ensure that the aims of the
strategy are met. The resulting 'delivered' allocations can then be converted back to the
corresponding 'discharge' or 'end -of -pipe' loads, if necessary.
The City's combined limits for TN and TP are the sums of the delivered allocations held by the TZO and
NBC plants.
• The NBC plant's allocations are the plant's base allocations under the Jordan WW rule.
NBC's TN allocation (delivered) = 110,698 Ib/yr
NBC's TP allocation (delivered) = 13,591 Ib/yr
Page 7
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 8 NPDES No. NC0047384
• The TZO plant's allocations include the plant's base allocations and those of the two schools that have
connected to the City's collection system, as follows:
TZO's TN allocation (delivered)
TZO's TP allocation (delivered) =
289,618 Ib/yr (Individual allocations are as originally
608 assigned under the Jordan WW rule.)
149
290,374 lb/yr delivered load
35,595 Ib/yr (Individual allocations are as originally
90 assigned under the Jordan WW rule.)
23
35,708 Ib/yr delivered load
(Allocations are not rounded but are displayed to the nearest 1 lb/yr. Sums are based on the actual, not
the displayed, allocations and may appear to be in error due to differences between the displayed and
true values.)
Again, the combined delivered allocations for the two plants are the sums of these delivered allocations:
Combined TN allocation/ limit =
Combined TP allocation/limit =
290,374 lb/yr TZO
110,698 NBC
401,072 lb/yr TN
35,708 Ib/yr TZO
13,591 NBC
49,299 lb/yr TP
The component and combined allocations are summarized here:
Transport
Factors
Allocations - TN
Allocations - TP
TN
TP
TN at EOP
(Ib/yr)
TN to Lake
(Ib/yr)
TP at EOP
(Ib/yr)
TP to Lake
(Ib/yr)
T.Z. Osborne WWTP
45%
44%
643,595
289,618
80,899
35,595
Northeast MS&HS
608
90
McLeansville MS
149
23
290,374
35,708
North Buffalo Creek
43%
42%
257,438
110,698
32,359
13,591
Combined ("bubble")
401,072
49,299
Page 8
Version: June 2, 2014

NPDES PERMIT FACT SHEET City of Greensboro- T.Z. Osborne
Page 9 NPDES No. NC0047384
3. The City requested that the permit address TN and TP allocations during the period of time
when the N. Buffalo Creek WWTP is off-line (and rescission of the NBC permit has occurred) and
all wastewaters are being treated at the T.Z. Osborne WWTP but the expansion has not been
completed.
Condition A.(3) in the permit has been modified to clarify that the TN and TP combined delivered
load limit will apply to T.Z. Osborne at a permitted flow of 40 MGD once the NBC permit is
rescinded and until the expansion is completed. Additionally, paragraph (a.) under Section A.(1.)
has been revised to reference condition A.(3.). where the combined delivered limitations for TN
and TP are described.
In addition, the following item was added to the final permit in response to comments from
DWR Public Water Supply Regional and Central Office staff.
• A special condition was added under Section A. (13.) stating that this permit may be reopened
and modified in the future to include 1,4-dioxane monitoring and/or reduction measures, if the
wastewater discharge is identified as contributing to violations of surface water quality
standards
Page 9
Version: June 2, 2014

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RECOMMENDED ACTION
No RP , Predicted Max >_ 50% of Allowable Cw -
defer to LTMP
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all samples < 2 ug/L
all samples < 5 ug/L
RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
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defer to LTMP
No RP , Predicted Max >_ 50% of Allowable Cw -
defer to LTMP
No RP, Predicted Max < 50% of Allowable Cw - No
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Acute: NO WQS
Chronic: 51.7
No o value > Allowable Cw
Chronic: 17.4
No value > Allowable Cw
Acute: NO WQS
Chronic 6.7
Acute: 15.4
Chronic: 2.1
Acute: 1,051.0
Chronic: 51.7
No value > Allowable Cw
' Acute: 7.5
Chronic: 7.2
1 I value(s) > Allowable Cw
Acute: 22.6
Chronic: 5.2
Acute: NO WQS
Chronic 1,861.0
No value > Allowable Cw
Acute: 34.8
Chronic: 25.8
No value > Allowable Cw
Acute: 268.4
Chronic: 91.0
No value > Allowable Cw
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Guilford WWTP
NC0047384
RECOMMENDED ACTION
Acute: NO WQS
Chronic51.2--- ----------------------------
N o value > Allowable Cw
Chronic: 15.3 No RP , Predicted Max a 50% of Allowable Cw -
No value > Allowable Cw defer to LTMP
Acute: NO WQS al samples < 5 ug/L
Chronic: 6.7 --- -------- --------------
Acute: 15.3 all samples < 2 ug/L
Chronic: 2.0 --- ----------------------------
Acute: 1,042.8 all samples < 5 ug/L — — — — — — — —
Chronic: 51.2
No value > Allowable Cw
Acute: 7.4 RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
Chronic------7.2 --- 11 value(s) > Allowable Cw
Acute: 22.4 all sample < 20 ug/L
Chronic: 5.1 --- ----------------------------
Acute: NO WQS
Chronic: 1,843.5 No RP , Predicted Max a 50%0 of Allowable Cw -
No value > Allowable Cw defer to LTMP
Acute: 34.5 No RP , Predicted Max >_ 50% of Allowable Cw -
defer to LTMP
Chronic:---- 25.6--------------------------
No value > Allowable Cw
Acute: 266.3 No RP, Predicted Max < 50% of Allowable Cw - No
Monitoring required — — — — — — — —
Chronic: 90.1
No value > Allowable Cw
REASONABLE POTENTIAL RESULTS
Max Pred
ri # Det. Cw Allowable Cw
M M
Q
z
Q
z
Vl
N
¢
z
1,300.0
O
^
co
V
co
M M
N h
O
O
O
0
co
o0
u11
tr.O
0o
0
c0
'0
co
u1
co
n
00
'0
SllNfl
00
ou
o�
0
�'0
1
0
on
0
Z
n
Z
on
0
lied
o
STANDARDS & CRITERIA (2)
NC WQS / Applied h FAV /
Chronic Standard Acute
50 FW(7Q10s)
10 HH/WS(Qavg)
6.5 FW(7Q10s)
2 FW(7Q10s) 15
50 FW(7Q10s) 1022
7 FW(7Q10s) 7.3
5 FW(7Q10s) 22
1800 FW(7Q10s)
25 FW(7Q10s) 33.8
0
N
0
a
0o
00
tu a_ ;a-
H V
0 0
z
0
0
Z
0
0
0
z
PARAMETER
Arsenic
Arsenic
E
0
N
Cadmium
Chromium
¢
Q
a.LTm 0
0
Cyanide
0)
9
0
V
J
)
U
Z
0
0)
a

/0
0
C
O
Q.
0.
all samples < 5 ug/L
z
a>
CO
CO
U
Z
U
00
N
w
0
U
Z
J
U
N
N
0
N
CO
CL

REASONABLE POTENTIAL ANALYSIS
Standard
Date
1 9/15/2010
2 12/29/2010
3 3/9/2011
4 6/8/2011
5 9/14/2011
6 12/14/2011
7 3/14/2012
8 6/20/2012
9 9/12/2012
10 12/11/2012
11 3/13/2013
12 9/18/2013
13 10/28/2013
14 10/29/2013
15 10/30/2013
16 10/31/2013
17 11/26/2013
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Data
BDL=1/2DL Results
10 5 Std Dev.
10 5 Mean
10 5 C.V.
10 5 n
11 11
8 8 Mult Factor =
4 4 Max. Value
10 5 Max. Pred Cw
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
SPECIAL -Values"
then "COPY" .
Maximum data
points = 58
1.6247
5.4706
0.2970
17
1.21
11.0 ug/L
13.3 ug/L
Chromium
Date Data
1 11/1/2013
2
3
4
5
6 10/1/2013
7
8
9
10
11
12
13
14 9/1/2013
15
16
17
18 8/1/2013
19
20
21
22 7/1/2013
23
24
25
26
27 5/1/2013
28
29
30
31
32 4/1/2013
33
34
35
36 3/1/2013
37
38
39
40 2/1/2013
41
42
43
44 1/1/2013
45
46
47
48
49 10/24/2012
50 10/31/2012
51 11/7/2012
52 11/14/2012
53 11/21/2012
54 11/28/2012
55 12/5/2012
56 12/11/2012
57 12/19/2012
58 12/26/2012
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
BDL=1/2DL Results
2.5 Std Dev. 0.0000
2.5 Mean 2.5000
2.5 C.V. 0.0000
2.5 n 58
2.5
2.5 Mult Factor = 1.00
2.5 Max. Value 2.5 ug/L
2.5 Max. Pred Cw 2.5 ug/L
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
2.5
5 2.5
NC0047384 9595 FRESHWATER RPA@40MGD 2014.xlsm, data
- 1 - 2/10/2014

REASONABLE POTENTIAL ANALYSIS
9
Copper (AL)
Date
1 11/21/2012
2 11/28/2012
3 12/5/2012
4 12/11/2012
5 12/19/2012
6 12/26/2012
7 1/2/2013
8 1/9/2013
9 1/16/2013
10 1/23/2013
11 1/29/2013
12 2/6/2013
13 2/13/2013
14 2/20/2013
15 2/26/2013
16 3/6/2013
17 3/13/2013
18 3/20/2013
19 3/26/2013
20 4/3/2013
21 4/10/2013
22 4/17/2013
23 4/23/2013
24 5/1/2013
25 5/8/2013
26 5/15/2013
27 5/22/2013
28 5/29/2013
29 6/5/2013
30 6/12/2013
31 6/19/2013
32 6/26/2013
33 7/3/2013
34 7/10/2013
35 7/17/2013
36 7/23/2013
37 7/31/2013
38 8/7/2013
39 8/14/2013
40 8/21/2013
41 8/28/2013
42 9/4/2013
43 9/11/2013
44 9/18/2013
45 9/25/2013
46 10/2/2013
47 10/9/2013
48 10/16/2013
49 10/23/2013
50 10/28/2013
51 10/29/2013
52 10/30/2013
53 10/31/2013
54 11/1/2013
55 11/6/2013
56 11/13/2013
57 11/20/2013
58 11/26/2013
Data
BDL=1/2DL Results
9 9 Std Dev.
8 8 Mean
6 6 C.V.
7 7 n
7 7
7 7 Mull Factor =
7 7 Max. Value
7 7 Max. Pred Cw
9 9
6 6
11 11
6 6
7 7
7 7
8 8
7 7
10 10
4 4
7 7
5 5
7 7
9 9
7 7
6 6
11 11
8 8
5 5
5 5
7 7
13 13
5 5
7 7
8 8
2 1
5 5
6 6
5 5
6 6
5 5
7 7
7 7
6 6
7 7
5 5
4 4
7 7
6 6
7 7
4 4
4 4
4 4
5 5
7 7
7 7
7 7
7 7
6 6
7 3.5
Use"PASTE SPECIAL
Values" then' 'COPY"
. Maximum data
points = 58
1.9686
6.5776
0.2993
58
1.00
13.0 ug/L
13.0 ug/L
11
Fluoride
Use"PASTE SPECIAL
Values" then "COPY"
. Maximum data
points -= 58
Date Data BDL=1/2DL Results
1 10/24/2012 600 600 Std Dev. 251.9855
2 10/31/2012 1100 1100 Mean 803.4483
3 11/7/2012 900 900 C.V. 0.3136
4 11/14/2012 1000 1000 n 58
5 11/21/2012 ';'' 1000 1000
6 11/28/2012 5 600 600 MultFactor= 1.00
7 12/5/2012 500 500 Max. Value 1300.0 ug/L
8 12/11/2012 1000 1000 Max. Pred Cw 1300.0 ug/L
9 12/19/2012 1000 1000
10 12/26/2012 1100 1100
11 1/2/2013 . 500 500
12 1/9/2013 700 700
13 1/16/2013 200 200
14 1/23/2013 500 500
15 1/29/2013 900 900
16 2/6/2013 1000 1000
17 2/13/2013 ; 600 600
18 2/20/2013 600 600
19 2/27/2013 600 600
20 3/6/2013 700 700
21 3/13/2013 600 600
22 3/20/2013 500 500
23 3/27/2013 500 500
24 4/3/2013 500 500
25 4/10/2013 . 400 400
26 4/17/2013 700 700
27 4/24/2013 500 500
28 5/1/2013 600 600
29 5/8/2013 > 700 700
30 5/15/2013 600 600
31 5/22/2013 500 500
32 5/29/2013 500 500
33 6/5/2013 .1 800 800
34 6/12/2013 700 700
35 6/19/2013 , 1100 1100
36 6/26/2013 900 900
37 7/3/2013 1200 1200
38 7/10/2013 800 800
39 7/17/2013 1200 1200
40 7/24/2013 900 900
41 7/31/2013 t 800 800
42 8/7/2013 800 800
43 8/14/2013 ' 700 700
44 8/21/2013 1000 1000
45 8/28/2013 900 900
46 9/4/2013 700 700
47 9/11/2013 800 800
48 9/18/2013 700 700
49 9/25/2013 900 900
50 10/2/2013 900 900
51 10/9/2013? 1100 1100
52 10/16/2013 1100 1100
53 10/23/2013 1300 1300
54 10/30/2013 1100 1100
55 11/6/2013 1000 1000
56 11/13/2013 1100 1100
57 11/20/2013 1300 1300
58 11/26/2013 s 1100 1100
NC0047384 9595 FRESHWATER RPA@40MGD 2014.xlsm, data
- 1 - 2/10/2014

REASONABLE POTENTIAL ANALYSIS
12
;Use"PASTE SPECIAL
.Values" then "COPY" .
,-Maximum data points
= 58
Lead
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Date Data
11/1/2013 <'..
10/1/2013 <
9/1/2013 <
8/1/2013
7/1/2013 1 H.
<
1<
<.
5/1/2013 <'
1<
<i
4/1/2013
3/1/2013
I<,
10/24/2012 <
10/31/2012 <
11/7/2012
11/14/2012
11/21/2012
11/28/2012
12/5/2012
12/11/2012
12/19/2012
12/26/2012
BDL=1/2DL Results
10 5 Std Dev. 2.0938
10 5 Mean 5.6034
10 5 C.V. 0.3737
10 5 n 58
10 5
10 5 Mult Factor 1.00
10 5 Max. Value 16.0 ug/L
10 5 Max. Pred Cw 16.0 ug/L
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
< 10 5
< 10 5
< 10 5
<' 10 5
<I 10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
16 16
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
13 13
10 5
10 5
10 10
10 10
10 5
10 5
10 5
10 5
10 5
<' 10 5
< 10 5
<' 10 5
<, 10 5
<; 10 5
11 11
< 10 5
<1 10 5
15
Nickel
Date Data BDL=1/2DL Results
1 9/5/2012 14.0 14 Std Dev.
2 9/12/2012 13.0 13 Mean
3 9/26/2012 21.0 21 C.V.
4 11/7/2012 42.0 42 n
5 11/14/2012 34.0 34
6 11/21/2012 f 24.0 24 Mult Factor =
7 11/28/2012 13.0 13 Max. Value
8 12/5/2012 k. ; 21.0 21 Max. Pred Cw
9 12/11/2012 31.0 31
10 12/19/2012 27.0 27
11 1/2/2013 15.0 15
12 1/9/2013 21.0 21
13 1/16/2013 24.0 24
14 1/23/2013 28.0 28
15 1/29/2013 17.0 17
16 2/6/2013 18.0 18
17 2/13/2013 12.0 12
18 2/20/2013 14.0 14
19 2/26/2013 13.0 13
20 3/13/2013 10.0 10
21 3/26/2013 40.0 40
22 4/3/2013 16.0 16
23 4/10/2013 20.0 20
24 4/17/2013 15.0 15
25 4/23/2013 = 15.0 15
26 5/15/2013 38.0 38
27 5/22/2013 40.0 40
28 5/29/2013 ,. 19.0 19
29 6/5/2013 17.0 17
30 6/12/2013 13.0 13
31 6/19/2013 26.0 26
32 6/26/2013 " 17.0 17
33 7/3/2013 20.0 20
34 7/10/2013 11.0 11
35 7/17/2013 16.0 16
36 7/23/2013 14.0 14
37 7/31/2013 =_; 20.0 20
38 8/7/2013 '2' 24.0 24
39 8/14/2013 ' 15.0 15
40 8/21/2013 13.0 13
41 8/28/2013 32.0 32
42 9/4/2013 12.0 12
43 9/11/2013 19.0 19
44 9/18/2013 18.0 18
45 9/25/2013 29.0 29
46 10/2/2013 14.0 14
47 10/9/2013 28.0 28
48 10/16/2013 14.0 14
49 10/23/2013 13.0 13
50 10/28/2013 18.0 18
51 10/29/2013 `.` 14.0 14
52 10/30/2013 13.0 13
53 10/31/2013 17.0 17
54 11/1/2013 19.0 19
55 11/6/2013 14.0 14
56 11/13/2013 14.0 14
57 11/20/2013 . v: 17.0 17
58 11/26/2013 14.0 14
Use "PASTE SPECIAL
Values" then "COPY" .
Maximum data points
= 58
7.9197
19.6552
0.4029
58
1.00
42.0 ug/L
42.0 ug/L
NC0047384 9595 FRESHWATER RPA@40MGD 2014.xlsm, data
- 1 - 2/10/2014

REASONABLE POTENTIAL ANALYSIS
16
Selenium
Date
1 11/1/2013
2
3 10/1/2013
4
5
6
7 9/1/2013
8 3/1/2013
9 1/26/2010
10 3/10/2010
11 4/27/2010
12 6/16/2010
13 9/15/2010
14 12/29/2010
15 3/9/2011
16 6/8/2011
17 9/14/2011
18 12/14/2011
19 3/14/2012
20 6/20/2012
21 9/12/2012
22 12/11/2012
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Data
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
BDL=1/2DL Results
10 5 Std Dev. 4.2795
10 5 Mean 5.8636
10 5 C.V. 0.7298
10 5 n 22
10 5
10 5 MultFactor= 1.39
10 5 Max. Value 25.0 ug/L
10 5 Max. Pred Cw 34.8 ug/L
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
10 5
25 25
4 4
10 5
10 5
10 5
18
Zinc (AL)
Date
1 11/21/2012
2 11/28/2012
3 12/5/2012
4 12/11/2012
5 12/19/2012
6 12/26/2012
7 1/2/2013
8 1/9/2013
9 1/16/2013
10 1/23/2013
11 1/29/2013
12 2/6/2013
13 2/13/2013
14 2/20/2013
15 2/26/2013
16 3/6/2013
17 3/13/2013
18 3/20/2013
19 3/26/2013
20 4/3/2013
21 4/10/2013
22 4/17/2013
23 4/23/2013
24 5/1/2013
25 5/8/2013
26 5/15/2013
27 5/22/2013
28 5/29/2013
29 6/5/2013
30 6/12/2013
31 6/19/2013
32 6/26/2013
33 7/3/2013
34 7/10/2013
35 7/17/2013
36 7/23/2013
37 7/31/2013
38 8/7/2013
39 8/14/2013
40 8/21/2013
41 8/28/2013
42 9/4/2013
43 9/11/2013
44 9/18/2013
45 9/25/2013
46 10/2/2013
47 10/9/2013
48 10/16/2013
49 10/23/2013
50 10/28/2013
51 10/29/2013
52 10/30/2013
53 10/31/2013
54 11/1/2013
55 11/6/2013
56 11/13/2013
57 11/20/2013
58 11/26/2013
Data
Use"PASTE SPECIAL
Values" then "COPY"
.-Maximum data
points = 68
BDL=1/2DL Results
82 82 Std Dev. 24.4843
60 60 Mean 79.4483
74 74 C.V. 0.3082
100 100 n 58
79 79
60 60 Mult Factor = 1.00
96 96 Max. Value 144.0 ug/L
105 105 Max. Pred Cw 144.0 ug/L
109 109
105 105
77 77
97 97
92 92
105 105
100 100
53 53
90 90
79 79
67 67
63 63
104 104
83 83
82 82
107 107
61 61
35 35
27 27
33 33
37 37
60 60
52 52
83 83
46 46
56 56
113 113
144 144
104 104
117 117
65 65
103 103
110 110
88 88
104 104
74 74
99 99
84 84
70 70
37 37
83 83
91 91
78 78
61 61
77 77
90 90
53 53
55 55
58 58
91 91
NC0047384 9595 FRESHWATER RPA@40MGD 2014.xlsm, data
- 1 - 2/10/2014

EFFLUENT ANALYSIS SUMMARY
NC0047384
Fecal Coliform (2011-2013)
1) 9.53 geo avg
< 100/100mL or 50 % of the monthly permit limit
2) 200% of 400/100 mL weekly avg limit = 800/100mL
2011 5 2012 0 2013 1
6 daily samples > 200% of permit limit
< 20 daily samples exceeded 200% of the 400/100 mL permit limit
3) no more than two weekly average limit violations in 2013 (none on record)
Reduce monitoring Frequency for fecal coliform to 2lweek
CBOD (2011-2013)
1) 7/12*4 mg/L + 5/12*8 mg/L = 5.67 mg/L weighted, annual monthly average
2.83 = 50% of wt. annual monthly average
2.7658551 2.77 three-year average is < 50% of the weighted annual monthly average limit
2) 200% of summer monthly avg. limit = 8 ml summer values > 8
2011 5 2012 3 2013 1
9 daily samples exceeded 200% of the monthly average summer limit
200% of winter monthly permit limit = 16 r winter values > 16
2011 0 2012 0 2013 0
no daily samples exceeded 200% of monthly average winter limit
only 15 exceedances allowed - 9 accounted for
3) no more than two weekly average limit violations in 2013 (none on record)
Reduce Monitoring Frequency for CBOD5 to 2lweek
TSS (2011-2013)
1) 30 mg/L monthly average permit limit
15 = 50% of monthly average permit limit
5.18 three-year average is < 50% of the monthly average permit limit
2) 200% of monthly average permit limit= 60 mg/L
2011 0 2012 1 2013 0
1 daily sample exceeded 200% of the monthly average limit
3) no more than two weekly average limit violations in 2013 (none on record)
Reduce Monitoring Frequency for TSS to 2/week
NH3-N (2011-2013)
1) 7/12*2 mg/L + 5/12`4 mg/L = 2.83 mg/L weighted, annual monthly average
1.42 = 50% of wt. annual monthly average
0.56 three-year average is < 50% of the weighted annual monthly average limit
2) 200% of summer monthly avg. limit = 4 mg/L summer values > 4
2011 10 2012 1 2013 0
11 daily samples exceeded 200% of the monthly average summer limit
200% of winter monthly permit limit = 8 mg/L winter values > 8
2011 7 2012 0 2013 0
0 0 0
7 daily samples exceeded 200% of monthly average winter limit
Total - 18 samples exceeded 200% of the monthly summer and winter averages (15 allowed)
3) no more than two weekly average limit violations in 2013 (none on record)
Monitoring Frequency for NH3-N remains the same
i

City of Greensboro T. Z. Osborne [NC0047384] Reduced Monitoring Request
The City of Greensboro hereby requests designation as an "Exceptional Performing Facility"
and reduced monitoring for the following parameters listed as daily monitoring in the current T.
Z. Osborne NPDES permit: CBOD5, TSS, NH3-N, and fecal coliforrn. A spreadsheet
summarizing the applicable data is also part of this submittal.
[Language from October 22, 2012 DWQ Guidance Regarding the Reduction of Monitoring
Frequencies in NPDES Permits for Exceptionally Performing Facilities]
Individual NPDES facilities shall submit a written request to modify their NPDES permit
specifying which parameters are to be considered for reduced monitoring . Permit holders
must include with their requests sufficient data, statistical analyses, and other information to
support the justification for reduced monitoring. NPDES permit staff shall review the application
and supporting information. Approval of reduced monitoring frequency shall be granted if all the
criteria below are met:
• The facility has no more than one civil penalty assessment for permit limit violations for each
target parameter during the previous three years.
o During CY 2010 to 2012, the T. Z. Osborne POTW was assessed the
following civil penalties for the four target parameters:
■ March 2011: $2599.52 for one MA NH3-N limit violation
• Neither the permittee nor any of its employees have been convicted of criminal violations of
the Clean Water Act within the previous five years.
o No City of Greensboro employees have been convicted of criminal
violations of the Clean Water Act within the previous five calendar years
(2008-2012)
• The facility is not currently under an SOC for target parameter effluent limit noncompliance.
o The T. Z. Osborne POTW is not currently under an SOC for CBOD6, TSS,
NH3-N, or fecal coliform violations.
• The facility is not on EPA's Quarterly Noncompliance Report for target parameter limit
violations.
o The City of Greensboro has not been notified that the T. Z. Osborne POTW
is on EPA's Quarterly Noncompliance Report for CBODS, NH3-N, TSS or
fecal coliform violations.
• For BOD5, CBOD5, TSS, NH3-N and TSS, the three year arithmetic mean of effluent data
must be less than fifty percent of the monthly average permit limit. For fecal coliform or
enterococci, the three year geometric mean must be less than 50 percent of the monthly
average permit limit. For parameters with summer and winter limits, an annual arithmetic
mean of the seasonal limits may be used in the calculation.
o The T. Z. Osborne CY2010-2012 effluent concentrations are less than 50%
of the NPDES monthly average limits as follows [see attached data
spreadsheet]:
City of Greensboro T. Z. Osborne NC0047384 Reduced Monitoring Request Submittal; 'April 2013 Page 1

NPDES/Aquifer Protection Permitting Unit Pretreatment information Request F•,ran
PERMIT WRITER COMPLETES THIS PART:
Check all that apply
Date of Request
Requestor
Facility Name
Permit Number
Region
Basin
12/8/2011.
Julie Grzyb
T.Z. Osborne
NC0047384
WSRO
municipal renewal
new industries
WWTP expansion
Speculative limits
stream reclass.
Cape Fear
outfall relocation
7Q10 change
other
other
PERMIT WRITERS- AFTER you get'this form back
from PERCS:
Notify PERCS if LTMP/STMP data we said should be
on DMRs is not really there, so we can get it for you
(or NOV POTW).
- Notify PERCS if you want us to keep a specific POC
in LTMP/STMP so you will have data for next permit
renewal.
- Email PERCS draft permit, fact sheet, RPA.
- Send PERCS paper copy of permit (w/o NPDES
boilerplate), cover letter, final fact sheet. Email RPA if
changes.
check applicable PERCS staff:
v BRD, CPF, CTB, FRB, TAR - Sarah Morrison (807-6310)
CHO, HIW, LUM, LTN, NES, NEW, ROA, YAD - Monti
Hassan (807-6314)
Other Comments to PERCS:
29 SIU's listed in permit application:
9 non -categorical and 20 CIU's
PERCS PRETREATMENT STAFF COMPLETES THIS PART:
Status of Pretreatment Program (check all that apply)
1) facility has no SIU's, does have Division approved Pretreatment Program that is INACTIVE
2) facility has no SIU's, does not have Division approved Pretreatment Program
3) facility has SlUs and DWQ approved Pretreatment Program (list "DEV" if program still under development)
3a) Full Program with LTMP
3b) Modified Program with STMP
4) additional conditions regarding Pretreatment attached or listed below
X
X
Flow, MGD
Industrial
�ontroIlable
Permitted
3.893
n/a
Actual
2.8817
17.62
Time period for Actual
May 2005-June 2007
May 2005-June 2007
Most recent:
Next Cycle:
STMP time frame:
a
F a
u
o
a.
Parameter'of
Concern (POC)
Check List
POC due to
NPDESI Non-
Disch Permit
Limit
Required by
EPA*
Required
by 503
Sludge**
POC due
to SIU***
POTW POC
(Explain
below)%°**
STMP
Effluent
Freq
LTMP
Effluent
Freq
X
BOD
X
X
4
Q
X
TSS
' X
X
4
Q
X
NH3
X
4
Q
X
Arsenic
X
X
4
Q
,/
Cadmium
X
X
X
4
' Q
,%
Chjem'iuni •
,j
X
X
4
Q
,4
.Copper
4
X
4
Q
X
Cyanide
X
X
4
Q
4
Lead..
,%
X
4
Q
X
Mercury
X
X
X
4
Q
M
Molybdenum
4
Q M
,f
Nickel
X.
4
X
X
4
Q
X
..
Silver
X
4
Q
X
Selenium
4
Q
4
Zinc
,%
X
4
Q
Total Nitrogen
•
4
Q
X
Phosphorus
X
X
4
Q
X
Beryllium
X
4
Q
F
Fluoride
X
4
Q M
4
Q M
4
Q M
Q = Quarterly
M = Monthly
Is all data on DMRs?
YES
NO (attach data)
X*
Is data in spreadsheet?
YES (email to writer)
NO
*Always in the LTMP/STMP ** Only in LTMP/STMP if sludge
land app or composte talc r��s ror memo arm ��
*** Only in LTMP/STMP while SIU still discharges to POTW • **** Only in LTMP/STMP when pollutant is still of concern to POTW
Comme nts to Permit Writer (ex., explanation of anv POCs; info you have on IU related investigations into NPDES problems): POTW
incinerates sludge (POCs are different than land application or composting). POTW also includes in the LTMP sampling for the following:
acetone and ethyl acetate (once/year influent/effluent),;antimony, cobalt, tin, titanium, vanadium, Bis (2-ethylhexyl) phthalate, carbazole, n-
Decane, fluoranthene, n-Octadecane, o-Cresol, p-Cresol and 2,4,6-Trichlorophenol (1/qtr influent/effluent).
— X*: Selenium is not listed on the DMRs as noted in the LTMP at a quarterly frequency. This POC is not required by EPA and since the
POTW does not land apply their sludge, it is not required by Part 503.
Copy of T Z Osborne PERCS NPDES request June_30_2011.xIsx
Revised: July 24, 2007

GIJJLL 1J1"a1L 1CIU1-111 fl_.di
Parameter
Reason for Rating
0J
From McConnell Rd to US 70
South Buffalo Creek
16-11-14-2b
co
rn
rn
Ecological/biological Integrity FishCom
Poor Bioclassification
4—
J
U
0
'CS
d)
0
E
From US 70 to Buffalo Creek
•South Buffalo Creek
16-11-14-2c
e Creek at US29
rorn SR 2426
0)
0)
1
0
0
0
0
Ecological/biological Integrity Benthos
Fair Bioclassification
CD
4--
J
U
(O
CT
0
0)
L
co
0
E
Page 5 of 177
Draft NC 303(d) List- Comments due March 12, 2012
Friday, February 10, 2012

North Carolina Wildlife Resources Commission
Gordon Myers, Executive Director
MEMORANDUM
TO: Julie Grzyb, NPDES Complex Permitting, Wastewater Branch
Division of Water Resources
FROM: Shari L. Bryant, Piedmont Region Coordinator 2h0 o
Habitat Conservation Program
DATE: 19 February 2014
SUBJECT: NPDES Permit Renewal and Expansion for City of Greensboro, T.Z. Osborne
Wastewater Treatment Plant, Guilford County, NPDES Permit No. NC0047384
Biologists with the North Carolina Wildlife Resources Commission have reviewed the subject
document. Our comments are provided in accordance with provisions of the Clean Water Act of 1977 (as
amended), Fish and Wildlife Coordination Act (48 Stat. 401, as amended; 16 U.S.C. 661-667e), and
North Carolina General Statutes (G.S. 113-131 et seq.).
The City of Greensboro has applied for a renewal of their NPDES permit to discharge 40 million
gallons per day (mgd) of treated municipal and industrial wastewater into South Buffalo Creek in the
Cape Fear River basin. The permit renewal also includes an expansion of the wastewater treatment plant
(WWTP) to 56 mgd. The proposed expansion includes transfer of wastewater from the North Buffalo
Creek WWTP (16 mgd) that will be decommissioned.
We provided comments on an Environmental Assessment (EA) for the proposed expansion of
T.Z. Osborne WWTP from 40 to 56 mgd. Based on information provided in the EA, it appears the
WWTP uses chlorine systems for disinfection, and the proposed expansion would continue to use
chlorine for disinfection. Also, the EA states ammonia speculative limits are 0.82 mg/L in summer and
1.64 mg/L in winter.
The instream waste concentration for this WWTP appears to be 90%. While we recognize there
are no listed aquatic species in South Buffalo Creek, it is likely water quality is a limiting factor in this
stream supporting a diverse aquatic community. We offer the following comments or recommendations
regarding the permit renewal and expansion.
1. We are pleased to see the speculative limits for ammonia -nitrogen of 0.82 mg/L in summer and
1.64 mg/L in winter as described in the EA have been included in this permit. Freshwater
mussels are among the most sensitive aquatic organisms tested for impacts from ammonia, and
ammonia may be a significant limiting factor for unionids (Augspurger et al., 2003).
Mailing Address: Division of Inland Fisheries • 1721 Mail Service Center • Raleigh, NC 27699-1721
Telephone: [phone] • Fax: [phone]

Page 2
19 February 2014
T.Z. Osborne WWTP
NPDES Pennit No. NC0047384
2. Rather than adding two new chlorine contact tanks, we recommend replacing the chlorine
disinfection systems with ultraviolet light or ozone systems. Chlorine is acutely toxic to aquatic
organisms and can form secondary compounds that are detrimental to aquatic life. Valenti (2006)
concluded the impact of long term exposure to low doses of chlorine may impact juvenile
mussels and reduce the chance of them being recruited to the reproducing population.
Thank you for the opportunity to comment on this permit renewal and expansion. If we can be of
further assistance, please contact our office at [phone] or shari.bryant(ncwildlife.org.
Literature cited
Augspurger, T., A. E. Keller, M. C. Black, W. G. Cope, and F. J. Dwyer. 2003. Derivation of water
quality guidance for protection of freshwater mussels (Unionidae) from ammonia exposure.
Environmental Toxicology and Chemistry 22(11):2569-2575.
Valenti, T.W., D.S. Cherry, R.J. Currie, R.J. Neves, J.W. Jones, R. Mair, and C.M. Kane. 2006. Chlorine
toxicity to early life stages of freshwater mussels (Bivalvia: Unionidae). Environmental
Toxicology and Chemistry, 25(9):2512-2518.