NC0037834_Technical Evaluation_20180118

Winston-Salem - Forsyth County
.Ci ,/County
Mutilifies
Water i Sewer - Solid Waste Disposal
January 18, 2018
RECEIVE®/®ENR/DWR
JAN 29 2010
Water Resources
Permitting Section
The City of Winston-Salem's Pretreatment Program is submitting written technical
evaluation of the need to revise local limits to comply with the following language
contained in Part IV, Section D (4.) of NPDES Permit NCO037834 issued to Archie
Elledge WWTP effective August 1, 2017 and NPDES Permit NCO050342 issued to
Muddy Creek WWTP effective September 1, 2017:
ce
Within 180 days of the effective date of this permit (or any subsequent permit
modification) the Permittee shall submit to the Division a written technical
evaluation of the need to revise local limits (i e an updated HW4 or documentation
of why one is not needed)[40 CFR 122 44] NPDES Permit NCO047384 issued
to the City of Greensboro T. Z. Osborne POTW was effective July 1, 2014.
Sincerely,
Joel Freeman/Sr. Chemist IWC
City Council Mayor Allen Jomes, Vivian H Burke, Mayor Pro Tempore, Northeast Ward, Demse D Adams, North Ward, Dan Besse, Southwest Ward, Robert C Clark, West Ward,
John C Larson, South Ward, Jeff Macintosh, Northwest Ward, Derwin L Montgomery, East Ward, James Taylor, Jr, Southeast Ward, City Manager Lee D Garrity
County Commissioners David R Plyler, Chairman, Don Martin, Vice Chair, Fleming El -Amin, Ted Kaplan, Richard V Linville, Glona D Whisenhunt, Everette Witherspoon,
ILULW County Manager Dudley Watts, Jr
Call 311 or 336-727-8000
City/County Uhhty Commission Randall S Tuttle Chairman, Wesley Curtis, Jr, Vice -Chau, Harold E Day, Tom Griffin, Yvonne H Htnes, Duane Long, Paul S McGill, David Neill,
[e-mail] Chris Parker, Jim Ruffin, Donald R Stewart
Mr. Monti Hassan
Manson Meads Complex
NC-DENR, DWQ, PERCS
1617 MAIL SERVICE CENTER
City of Winston-Salem
RALEIGH, NC 27699-1617
27 99 Griffith Road
Winston-Salem, NC 27103
CiryLink 311 (336 727 8000)
Subject: Local Limits
Fax [phone]
www utyofws org
Dear Mr. Hassan,
RECEIVE®/®ENR/DWR
JAN 29 2010
Water Resources
Permitting Section
The City of Winston-Salem's Pretreatment Program is submitting written technical
evaluation of the need to revise local limits to comply with the following language
contained in Part IV, Section D (4.) of NPDES Permit NCO037834 issued to Archie
Elledge WWTP effective August 1, 2017 and NPDES Permit NCO050342 issued to
Muddy Creek WWTP effective September 1, 2017:
ce
Within 180 days of the effective date of this permit (or any subsequent permit
modification) the Permittee shall submit to the Division a written technical
evaluation of the need to revise local limits (i e an updated HW4 or documentation
of why one is not needed)[40 CFR 122 44] NPDES Permit NCO047384 issued
to the City of Greensboro T. Z. Osborne POTW was effective July 1, 2014.
Sincerely,
Joel Freeman/Sr. Chemist IWC
City Council Mayor Allen Jomes, Vivian H Burke, Mayor Pro Tempore, Northeast Ward, Demse D Adams, North Ward, Dan Besse, Southwest Ward, Robert C Clark, West Ward,
John C Larson, South Ward, Jeff Macintosh, Northwest Ward, Derwin L Montgomery, East Ward, James Taylor, Jr, Southeast Ward, City Manager Lee D Garrity
County Commissioners David R Plyler, Chairman, Don Martin, Vice Chair, Fleming El -Amin, Ted Kaplan, Richard V Linville, Glona D Whisenhunt, Everette Witherspoon,
ILULW County Manager Dudley Watts, Jr
Call 311 or 336-727-8000
City/County Uhhty Commission Randall S Tuttle Chairman, Wesley Curtis, Jr, Vice -Chau, Harold E Day, Tom Griffin, Yvonne H Htnes, Duane Long, Paul S McGill, David Neill,
[e-mail] Chris Parker, Jim Ruffin, Donald R Stewart

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
`- City of Winston- Salem Muddy Creek WWTP NC0050342
The City of Winston- Salem's Pretreatment Program is submitting written technical evaluation of local
limits to comply with section D (4) of the NPDES Permit NC0050342.
Written Technical Evaluation of each NPDES Limited Parameter
1. NPDES Permit Limited Parameters for which neither a Maximum Allowable Headwork's Loading no
Local Limits are calculated.
The following parameters warranted no written technical evaluation outfall 001
• Flow: 21MGD Monthly average limit (same as previous permit).
• Fecal Coliform• Weekly Average of 400 colonies/100 ml and Monthly Average of 200
Colonies/100ml limits (same as previous permit).
• Dissolved Oxygen: Daily Average of >_ S.Omg/L limit (same as previous permit).
• Whole Effluent Toxicity• Evaluated using Chronic Toxicity(Ceriodaphnia) limit Pass/Fail
test at 5.5% effluent limit (same as previous permit).
• Total Residual Chlorine. 28 µg/L Daily Maximum limit (changed since previous permit).
• CBOD5. Monthly average and Total Suspended concentrations shall not exceed 15% of the
respectively influent value (85%) removal (same as previous permit).
The following parameters warranted no written technical evaluation outfall 002
• Fecal Coliform• Weekly Average of 400 colonies/100 ml and Monthly Average of 200
Colonies/100ml limits (same as previous permit).
• Dissolved Oxygen. Daily Average of >_ 5.Omg/L limit (same as previous permit).
• Whole Effluent Toxicity: Evaluated using Chronic Toxicity(Ceriodaphnia) limit Pass/Fail
test at 5.5% effluent limit (same as previous permit).
• CBOD5: Monthly average and Total Suspended concentrations shall not exceed 15% of the
respectively influent value (85%) removal (same as previous permit).

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Muddy Creek WWTP NC0050342
Carbonaceous Biochemical Oxygen Demand (CBODs) Outfall 001
The BODS monthly average 25.Omg/L and weekly average of 40.Omg/L limits are the same as the
previous NPDES permit Current values of the Influent design has changed do to upgrades at the
POTW since the last Headwork's submittal in 2012. The POTW has not seen any changes such as
flows, removal rate, and loadings to change limit. Local limits for Headwork's 2017 will remain valid.
Carbonaceous Biochemical Oxygen Demand (BODS) Outfall 002
The BODS monthly average 25 Omg/L and monthly average 40.Omg/L limits are the same as the
previous NPDES permit. Calculated MAHL based on 15 times the design. Current values of the
Influent design has changed do to upgrades at the POTW since the last Headwork's submittal in 2012.
The POTW has not seen any changes such as flows, removal rate, and loadings to change limit Local
limits for Headwork's 2017 will remain valid.
Total Suspended Solids (TSS)
The Total Suspended Solids monthly average of 30.Omg/I and weekly average of 45.Omg/L are the
same in the previous NPDES permit. MAHL based on 15 times the design. Current values of the
Influent design has changed do to upgrades at the POTW since the last Headwork's submittal in 2012.
The POTW has not seen any changes such as flows, removal rate, and loadings to change limit. Local
limits for Headwork's 2017 will remain valid.
4. Ammonia Nitrogen (NH3-N) Outfall 001
The Ammonia Nitrogen for summer monthly average of 14mg/L and weekly average of 35 are the
same as the previous NPDES permit. Current values of the Influent design has changed do to upgrades
at the POTW since the last Headwork's submittal in 2012. The POTW has not seen any changes such as
flows, removal rate, and loadings to change limit. Local limits for Headwork's 2017 will remain valid
4. Ammonia Nitrogen (NH3-N) Outfall 002
The Ammonia Nitrogen for summer monthly average of 14mg/L and weekly average of 35 are the
same as the previous NPDES permit. Current values of the Influent design has changed do to upgrades
at the POTW since the last Headwork's submittal in 2012. The POTW has not seen any changes such as
flows, removal rate, and loadings to change limit. Local limits for Headwork's 2017 will remain valid
5. Total Phosphorus
Monthly samples are collected for the Yadkin Pee -Dee River Basin nutrient management strategy
Monitoring and reporting only. Is pollutant of concern in the Long Term Monitoring Plan
6. Total Nitrogen (NO2+NO3+TKN)
Monitoring and reporting only. Is pollutant of concern in the Long Term Monitoring Plan

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
f City of Winston- Salem Muddy Creek WWTP NC0050342
The following parameters are required Pollutants of Concern.
1. Arsenic
Arsenic is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.
Cadmium
Cadmium Arsenic is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
Chromium
Chromium is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
4. Copper
Copper is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid
5. Cyanide
Copper is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.
Lead
Lead is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit. The
MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are still
valid.
7. Mercury
Mercury is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.
8. Molybdenum
Molybdenum is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in allocations for this
parameter are still valid
Nickel
Nickel is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Muddy Creek WWTP NC0050342
10 Selenium
Selenium is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in allocations for this
parameter are still valid.
11. Silver
Sliver is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
12. Zinc
Zinc is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit. The
MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are still
valid.

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Archie Elledge WWTP NC0037834
The City of Winston- Salem's Pretreatment Program is submitting written technical evaluation of local
limits to comply with section D (4) of the NPDES Permit NC0037834.
Written Technical Evaluation of each NPDES Limited Parameter
1. NPDES Permit Limited Parameters for which neither a Maximum Allowable Headwork's Loading no
Local Limits are calculated.
The following parameters warranted no written technical evaluation:
•
Flow- 30MGD Monthly average limit (same as previous permit)
• Fecal Coliform. Weekly Average of 400 colonies/100 ml and Monthly Average of 200
Colonies/100ml limits (same as previous permit).
• Dissolved Oxygen: Daily Average of >_ 6.5 mg/L limit (same as previous permit).
• Whole Effluent Toxicity: Evaluated using Chronic Toxicity(Ceriodaphnia) limit Pass/Fail
test at 76% effluent limit (same as previous permit).
• Total Residual Chlorine. 22.5 µg/L Daily Maximum limit (changed since previous permit)
• BODs: Monthly average and Total Suspended concentrations shall not exceed 15% of the
respectively influent value (85%) removal (same as previous permit).
2. Biochemical Oxygen Demand (BODO
The BODS for summer of the monthly average 21.Omg/L and winter monthly average 30.Omg/L limits
are the same as the previous NPDES permit. The BOD -9 for summer of the weekly average of 31.5mg/L
and winter weekly average 45.Omg/L limits are the same as the previous NPDES permit Calculated
MAHL based on 15 times the design. Current values of the Influent design has changed do to
upgrades at the POTW since the last Headwork's submittal in 2012. The POTW has not seen any
changes such as flows, removal rate, and loadings to change limit. Local limits for Headwork's 2017
will remain valid
Total Suspended Solids (TSS)
The Total Suspended Solids monthly average of 30.0mg/I and weekly average of 45.Omg/L are the
same in the previous NPDES permit. MAHL based on 1.5 times the design. Current values of the
Influent design has changed do to upgrades at the POTW since the last Headwork's submittal in 2012.
The POTW has not seen any changes such as flows, removal rate, and loadings to change limit Local
limits for Headwork's 2017 will remain valid.
4. Ammonia Nitrogen (NH3-N)
The Ammonia Nitrogen for summer monthly average of 12mg/L and weekly average of 3.6 are the
same as the previous NPDES permit. The Ammonia Nitrogen for winter monthly average of 9.Omg/L
and weekly average of 27mg/L are the same as the previous NPDES. The Ammonia Nitrogen for winter
monthly average of 2.4mg/L and weekly average of 7.2mg/L are the same as the previous NPDES. The
winter limits of 2.4mg/L and 7.2mg/L shall become effective May 31, 2018 Current values of the
Influent design has changed do to upgrades at the POTW since the last Headwork's submittal in 2012
The POTW has not seen any changes such as flows, removal rate, and loadings to change limit. Local
limits for Headwork's 2017 will remain valid

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Archie Elledge WWTP NC0037834
Total Phosphorus
Monthly samples are collected for the Yadkin Pee -Dee River Basin nutrient management strategy
Monitoring and reporting only. Is pollutant of concern in the Long Term Monitoring Plan.
6. Total Nitrogen (NO2+NO3+TKN)
Monitoring and reporting only Is pollutant of concern in the Long Term Monitoring Plan.
The following parameters are required Pollutants of Concern:
1. Arsenic
Arsenic is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.
2 Cadmium
Cadmium Arsenic is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid. Cadmium will be tested at its lowest reporting level of 0 5 µg/L
3. Chromium
Chromium is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
4. Copper
Copper is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.
5. Cyanide
Copper is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid. Total cyanide shall be detected to a reporting level of 20.0 µg/L Total cyanide levels
reported <20 0 µg/L shall be considered zero for compliance purposes.
6. Lead
Lead is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit The
MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are still
valid.
7. Mercury
Mercury is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit.
The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are
still valid.

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Archie Elledge WWTP NC0037834
8. Molybdenum
Molybdenum is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit The MAHL in the 2017 WQS pass-through resulted in allocations for this
parameter are still valid
Nickel
Nickel is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
10. Selenium
Selenium is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit. The MAHL in the 2017 WQS pass-through resulted in allocations for this
parameter are still valid.
11. Silver
Sliver is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES
Permit The MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this
parameter are still valid.
12. Zinc
Zinc is a Long Term Monitoring Plan monitoring parameter and is not limited in NPDES Permit. The
MAHL in the 2017 WQS pass-through resulted in local limits/allocations for this parameter are still
valid. Zinc shall be tested to its lowest reporting level of 0.5 pg/L.

WRITTEN TECHNICAL EVALUATION OF THE NEED TO REVISE LOCAL LIMITS
City of Winston- Salem Archie Elledge WWTP NC0037834