NC0024201_Permit (Modification)_20050511

NPDES DOCIMENT SCANNING COVER SHEET
NPDES Permit:
NC0024201
Roanoke River WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
Report
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
May 11, 2005
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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
May 11, 2005
Mr. Dan Brown, CEO
Roanoke Rapids Sanitary District
P.O. Box 308
Roanoke Rapids, North Carolina 27870
Subject: NPDES Permit Modification
Permit Number NC0024201
Roanoke Rapids WWTP
Halifax County
Dear Mr. Brown:
Division personnel have reviewed and approved your request for modification of the above referenced
permit. Accordingly, we are forwarding herewith the attached modified NPDES discharge permit. This permit
modification includes a change to the effluent mercury limitation for the discharge to the Roanoke River and
elimination of any reference to required method 1631 sampling. Based on upstream mercury date collected
by the facility during the previous year, the effluent mercury limitation has been recalculated assuming a
background mercury concentration of approximately 2.6 ng/L. This background concentration in
conjunction with a 7Q10 flow of 1172 cfs yields an effluent limitation of 0.868 µg/L.
This permit modification 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).
If you have any questions or need additional information, please do not hesitate to contact Mark
McIntire of my staff at [phone], extension 508.
Sincerely,
ORIGINAL SIGNED BY
Mark McIntire
Alan W. Klimek, P.E.
cc: Central Files
NPDES Unit Files ,
Raleigh Regional Office
Aquatic Toxicology Unit
EPA Region 4, Roosevelt Childress
One
NorthCarolina
Natural!!!
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]
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Permit NC0024201
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions 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, the
Roanoke Rapids Sanitary District
is hereby authorized to discharge wastewater from a facility located at the
Roanoke Rapids Sanitary District WWTP
135 Aqueduct Road
Weldon
Halifax County
to receiving waters designated as Chockoyotte Creek at the Roanoke River in the Roanoke
River Basin in accordance with effluent limitations, monitoring requirements, and other
conditions set forth in Parts I, II, and III hereof.
The permit shall become effective June 1, 2005.
This permit and the authorization to `discharge +s1iall expire at midnight on March 31, 2007.
Signed this day May 11, 2005.
ORIGINAL SIGNED BY
Mark McIntire
Alan W. Klimek, P.E., Director
Division of Water Quality
By Authority of the Environmental Management Commission

Permit NC0024201
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.
The Roanoke Rapids Sanitary District is hereby authorized to:
1. Continue to operate an existing 8.34 MGD wastewater treatment facility located at 135 Aqueduct
Road near Weldon in Halifax County. This facility discharges through outfall 001 and includes the
following wastewater treatment components:
• Bar screen and grit chamber
• Dual primary clarifiers
• Dual trickling filters
• Three Aeration basins
• Dual final clarifiers
■ Chlorination
• Dechlorination
• Dual Secondary sludge thickener
• Three anaerobic digesters
• Lime stabilization
■ Sludge storage
• Sludge drying beds
2. Discharge from said treatment works at the location specified on the attached map through outfall
001 into Chockoyotte Creek, a class C water in the Roanoke River Basin.
3. Upon relocation of the outfall, discharge from said treatment works at the location specified on the
attached map through outfall 001 into the Roanoke River, a class C water in the Roanoke River
Basin.

Roanoke Rapids Sanitary District
- NC0024201
USGS Quad Name: Weldon
Receiving Stream: Roanoke River
Stream Class: C
Subbasin: Roanoke - 030208
Lat.: 36°26'10"
Long.: 77°36'04"
Not to SCALE

Permit NC0024201
A. (1) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
(DISCHARGES TO CHOCKOYOTTE CREEK THROUGH MAY 31, 2005)
Beginning on the effective date of this permit and lasting until May 31, 2005 or until relocation of
the outfall to the Roanoke River is complete, the Permittee is authorized to discharge treated
wastewater from Outfall 001. Such discharges shall be limited and monitored by the Permittee as
specified below:
EFFLUENT
CHARACTERISTICS
EFFLUENT LIMITATIONS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
'Sample
Location'
Flow
8.34 MGD
Continuous
Recording
Influent or
Effluent
CBOD, 5-day, 20°C2
25.0 mg/L
37.5 mg/L
Daily
Composite
Influent &
Effluent
Total Suspended Solids2
30.0 mg/L
45.0 mg/L
Daily
Composite
Influent &
Effluent
NH3 as N
Daily
Composite
Effluent
Total Residual Chlorine
28 pg/L
Daily
Grab
Effluent
Fecal Coliform
(geometric mean)
200/100 ml
400/100 ml
Daily
Grab
Effluent
pH
Between 6.0 and 9.0 Standard Units
Daily
Grab
Effluent
Dissolved Oxygen
Daily
Grab
Effluent
Temperature
Daily
Grab
Effluent
Total Nitrogen
(NO2 + NO3 + TKN)
Monthly
Composite
Effluent
Total Phosphorus
Monthly
Composite
Effluent
TotstLMe-reury3---
Monthly
Grab
Effluent, U
Total Copper
lc
4uj
Monthly
Composite
Effluent
Total Zinc
`_
i
Monthly
Composite
Effluent
Monthly
Composite
Effluent
-Total-Seleniun—
Monthly
Composite
Effluent
otai i itmride---
Chronic Toxicity3
Quarterly
Composite
Effluent
Dissolved Oxygen
Variable4
Grab
U, D
Temperature
Variable4
Grab
U, D
Notes:
1. U: Upstream at 308 Rollingwood Road, on the Roanoke River and the U.S. 158 crossing at Chockoyotte Creek.
D: Downstream at U.S. 158 crossing at the Roanoke River.
2. The monthly average effluent CBOD5 and TSS concentrations shall not exceed 15% of the respective influent
value (85% removal).
3. Chronic Toxicity (Ceriodaphnia) at 39 %; January, April, July and October (see condition A. (4)).
4. Upstream/downstream samples shall be collected 3/Week during June, July, August, September, and 1 /Week
during the remaining months of the year. Stream sampling may be discontinued at such times as flow
conditions in the receiving waters or extreme weather conditions will result in substantial risk of injury or
death to persons collecting samples. In such cases, on each day that sampling is discontinued, written
justification for the discontinuance shall be specified in the monitoring report for the month in which the event
occurred. Stream sampling shall be resumed at the first opportunity after the risk period has ceased.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Permit NC0024201
A. (2) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
(DISCHARGES TO CHOCKOYOTTE CREEK AFTER MAY 31, 2005)
Beginning on June 1, 2005 and lasting until relocation to the Roanoke River or until permit
expiration, the Permittee is authorized to discharge treated wastewater from Outfall 001. Such
discharges shall be limited and monitored by the Permittee as specified below:
7 .. t .ter..
U4t& i
.. . - . �1.; ..,. :.�.
. -. : }..
91,tb • I
`
- i Z
0
. }.
' Mon"t
4
n a . trr
a � -
d�<� •4J. » 4y .. +R{i�
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LIRA, r t�`i
,;G` ;w'b,,,5iYts LrR
�r
d1w41 iaef1�'
i '.tAm'•NY lew`K
Flow
8.34 MGD
Continuous
Recording
I Effleent r
CBOD, 5-day, 20°C2
25.0 mg/L
37.5 mg/L
Daily
Composite
Influent &
Effluent
Total Suspended Solids2
30.0 mg/L
45.0 mg/L
Daily
Composite
Influent &
Effluent
NH3 as N
Daily
Composite
Effluent
Total Residual Chlorine
28 pg/L
Daily
Grab
Effluent
Fecal Coliform
(geometric mean)
200/100 ml
400/100 ml
Daily
Grab
Effluent
pH
Between 6.0 and 9.0 Standard Units
Daily
Grab
Effluent
Dissolved Oxygen
Daily
Grab
Effluent
Temperature
Daily
Grab
Effluent
Total Nitrogen
(NO2 + NO3 + TKN)
Monthly
Composite
Effluent
Total Phosphorus
Monthly
Composite
Effluent
Total Mercury3
0.031 pg/L
Weekly
Grab
Effluent, U
Total Copper
Monthly
Composite
Effluent
Total Zinc
Monthly
Composite
Effluent
Total Selenium
12.8 pg/L
Weekly
Composite
Effluent
Total Fluoride
4.62 mg/L
Weekly
Composite
Effluent
Chronic Toxicity3
Quarterly
Composite
Effluent
Dissolved Oxygen
Variable4
Grab
U, D
Temperature
Variable4
Grab
U, D
Notes:
1. U: Upstream at 308 Rollingwood Road, on the Roanoke River and the U.S. 158 crossing at Chockoyotte Creek.
D: Downstream at U.S. 158 crossing at the Roanoke River.
2. The monthly average effluent CBOD5 and TSS concentrations shall not exceed 15% of the respective influent
value (85% removal).
3. Chronic Toxicity (Certodaphnia) at 39 %; January, April, July and October (see condition A. (4)).
4. Upstream/downstream samples shall be collected 3/Week during June, July, August, September, and 1/Week
during the remaining months of the year. Stream sampling may be discontinued at such times as flow
conditions in the receiving waters or extreme weather conditions will result in substantial risk of injury or
death to persons collecting samples. In such cases, on each day that sampling is discontinued, written
justification for the discontinuance shall be specified in the monitoring report for the month in which the event
occurred. Stream sampling shall be resumed at the first opportunity after the risk period has ceased.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Permit NC0024201
A. (3) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
(DISCHARGES AFTER OUTFALL RELOCATION)
Beginning upon relocation of the outfall to the Roanoke River and lasting until permit expiration, the
Permittee is authorized to discharge treated wastewater from Outfall 001. Such discharges shall be
limited and monitored by the Permittee as specified below:
, :. '{•
1 CTE ST1CS
.., :a. ... i.. ....i.. ...
T ITA
O(
pA )!G ice'
Mit oy
A e
:i'. ...,a ..>. n.,, e...T.
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Ii
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: i 1 I f.%�
L oca 9D
:S c.E u, iti ....
Flow
8.34 MGD
Continuous
Recording
Influent or
Effluent
CBOD, 5-day, 20°C2
25.0 mg/L
37.5 mg/L
Daily
Composite
Influent &
Effluent
Total Suspended Solids2
30.0 mg/L
45.0 mg/L
Daily
Composite
Influent &
Effluent
NH3 as N
Daily
Composite
Effluent
Total Residual Chlorine
28 pg/L
Daily
Grab
Effluent
Fecal Coliform
(geometric mean)
200/100 ml
400/100 ml
Daily
Grab
Effluent
pH
Between 6.0 and 9.0 Standard Units
Daily
Grab
Effluent
Dissolved Oxygen
Daily
Grab
Effluent
Temperature
Daily
Grab
Effluent
Total Nitrogen
(NO2 + NO3 + TKN)
Monthly
Composite
Effluent
Total Phosphorus
Monthly
Composite
Effluent
Total Mercury
0.868 pg/L
Weekly
Grab
Effluent, U
Total Copper
Monthly
Composite
Effluent
Total Zinc
Monthly
Composite
Effluent
Total Selenium
Monthly
Composite
Effluent
Total Fluoride
Monthly
Composite
Effluent
Chronic Toxicity3
Quarterly
Composite
Effluent
Dissolved Oxygen
Variable4
Grab
U, D
Temperature
Variable4
Grab
U, D
Notes:
1. U: Upstream at 308 Rollingwood Road. D: Downstream at the U.S. 158 crossing at the Roanoke River.
2. The monthly average effluent CBOD5 and TSS concentrations shall not exceed 15% of the respective influent
value (85% removal).
3. Chronic Toxicity (Ceriodaphnia) at 1.1 %; January, April, July and October (see condition A. (5)).
4. Upstream/downstream samples shall be collected 3/Week during June, July, August, September, and 1/Week
during the remaining months of the year. Stream sampling may be discontinued at such times as flow
conditions in the receiving waters or extreme weather conditions will result in substantial risk of injury or
death to persons collecting samples. In such cases, on each day that sampling is discontinued, written
justification for the discontinuance shall be specified in the monitoring report for the month in which the event
occurred. Stream sampling shall be resumed at the first opportunity after the risk period has ceased.
There shall be no discharge of floating solids or visible foam in other than trace amounts.

Permit NC0024201 •
A. (4) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
(DISCHARGES TO CHOCKOYOTTE CREEK)
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to
Ceriodaphnia dubia at an effluent concentration of 39%.
The permit holder shall perform at a minimum, quarterIti 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, July 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 anysingle 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: North Carolina Division of Water quality
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 NC0024201
A. (5) CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY)
(DISCHARGES AFTER OUTFALL RELOCATION)
The effluent discharge shall at no time exhibit observable inhibition of reproduction or significant mortality to
Ceriodaphnia dubia at an effluent concentration of 1.1%.
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, July 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: North Carolina Division of Water Quality
Environmental Sciences Branch
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
Completed Aquatic Toxicity Test Forms shall be flied 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 NC0024201
A. (6) EFFLUENT POLLUTANT SCAN
The permittee shall perform an annual Effluent Pollutant Scan for all parameters listed in the attached table (in
accordance with 40 CFR Part 136). Samples shall represent seasonal variations. Unless otherwise indicated,
metals shall be analyzed as "total recoverable."
Ammonia (as N) Trans-1,2-dichloroethylene Bis (2-chloroethyl) ether
Chlorine (total residual, TRC) 1,1-dichloroethylene Bis (2-chloroisopropyl) ether
Dissolved oxygen 1,2-dichloropropane Bis (2-ethylhexyl) phthalate
Nitrate/Nitrite 1,3-dichloropropylene 4-bromophenyl phenyl ether
Kjeldahl nitrogen Ethylbenzene Butyl benzyl phthalate
Oil and grease Methyl bromide 2-chloronaphthalene
Phosphorus Methyl chloride 4-chlorophenyl phenyl ether
Total dissolved solids Methylene chloride Chrysene
Hardness 1,1,2,2-tetrachloroethane Di-n-butyl phthalate
Antimony Tetrachloroethylene Di-n-octyl phthalate
Arsenic Toluene Dibenzo(a,h)anthracene
Beryllium 1,1,1-trichloroethane 1,2-dichlorobenzene
Cadmium 1,1,2-trichloroethane 1,3-dichlorobenzene
Chromium Trichloroethylene 1,4-dichlorobenzene
Copper Vinyl chloride 3,3-dichlorobenzidine
Lead Acid -extractable compounds: Diethyl phthalate
Mercury P-chloro-m-creso Dimethyl phthalate
Nickel 2-chlorophenol 2,4-dinitrotoluene
Selenium 2,4-dichlorophenol 2,6-dinitrotoluene
Silver 2,4-dimethylphenol 1,2-diphenylhydrazine
Thallium 4,6-dinitro-o-cresol Fluoranthene
Zinc 2,4-dinitrophenol Fluorene
Cyanide 2-nitrophenol Hexachlorobenzene
Total phenolic compounds 4-nitrophenol Hexachlorobutadiene
Volatile organic compounds: Pentachlorophenol Hexachlorocyclo-pentadiene
Acrolein Phenol Hexachloroethane
Acrylonitrile 2,4,6-trichlorophenol Indeno(1,2,3-cd)pyrene
Benzene Base -neutral compounds: Isophorone
Bromoform Acenaphthene Naphthalene
Carbon tetrachloride Acenaphthylene Nitrobenzene
Chlorobenzene Anthracene N-nitrosodi-n-propylamine
Chlorodibromomethane Benzidine N-nitrosodimethylamine
Chloroethane Benzo(a)anthracene N-nitrosodiphenylamine
2-chloroethylvinyl ether Benzo(a)pyrene Phenanthrene
Chloroform 3,4 benzofluoranthene Pyrene
Dichlorobromomethane Benzo(ghi)perylene 1,2,4-trichlorobenzene
1,1-dichloroethane Benzo(k)fluoranthene
1,2-dichloroethane Bis (2-chloroethoxy) methane
Test results shall be reported to the Division in DWQ Form- A MR-PPA1 or in a form approved by the Director
within 90 days of sampling. Two copies of the report shall be submitted along with the DMR to the following
address: Division of Water Quality, Water Quality Section, Central Files, 1617 Mail Service Center, Raleigh, North
Carolina 27699-1617.
A. (7) METALS REOPENER
The Permittee may request modification of the effluent limitations/upstream monitoring for metals described
herein after 12 months of data collection.

AMENDMENT TO FACT SHEET
ROANOKE RAPIDS SANITARY DISTRICT
NC0024201 - MARCH 14, 2005
During the previous permit renewal, a reasonable potential analysis (RPA) was conducted for
total mercury. In addition, the US EPA required the North Carolina Division of Water Quality to
require the facility to meet a 12 ng/L total mercury limit end -of -pipe because the receiving
stream is listed for a fish consumption advisory. While it is widely recognized that the vast
majority of the mercury problem stems from atmospheric deposition, EPA was unyielding on
the matter. EPA did agree to a course of action to help solve this facility's mercury problem. If
the facility conducted upstream method 1631 sampling and if those samples were below the
state water quality standard of 12 ng/L, they could request a modification to the permit
allowing for a dilution calculation assuming a background concentration. The table below
summarized the mercury date collected by the facility. The allowable concentration
calculations follow.
SP ��� A•..,; .Jt SbfgV..�rsii
.1yli�.
Iz �i <eft fl
y,.•,J� SYS yr l i j P"«
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.F': , J'
'w..k'd'�r�.
fi•$MMA lti' 4 I .'�
.i,i..'.;C I N.�.. iN
r'M 1 [ fr
a 9r,Rc s .'
vs+.�J
i` .�iC S �`
�i It"91r. do " Slr�
i
7l'
' l= S 7 �'I rd)13
`� S'S
.t.'.ia`x. � _. .ye,.... ..�
j� i3 P4-SS..-t'. �[+i 44it� i! 1
r' a.•'+fly7 'r'V�R
t i� In'.�y.•47!"
-rl
•.'l{ iK 1 lY rY:gl 1pl
Arc .F '-.. 'rIk4 P h
�are's�, a�: JSL^a��Y.�rf=.1>lw�..
October 2003
1.53
8.1
1.10
November 2003
1.48
19.0
1.43
December 2003
2.15
17.2
2.24
January 2004
1.9
40.0
2.02
February 2004
2.1
12.8
5.04
March 2004
3.76
8.4
1.31
April 2004
1.07
16.0
1.60
May 2004
4.46
8.1
2.58
June 2004
2.75
29.8
<1.0
July 2004
2.75
21.3
1.58
Fluoride
4.38
14.8
<1.0
The 7910 flow of the Roanoke River is approximately 1172 cfs. The permitted flow from the
facility is 8.34 MGD or 12.902 cfs. The upstream mercury concentrations in the above table
were averaged to yield a background concentration of 2.575 ng/L. The allowable concentration
is thus:
_ (1172 + 12.902)• 12 - (1172) • 2.575
12.902
Ca = 868 ng/L
The permit (NC0024201) will be reopened and modified to include a revised mercury limit for •
the discharge to the Roanoke River.

„oriel) sr,,4s
2,; A ;o UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
tJ
w REGION 4
ATLANTA FEDERAL CENTER
61 FORSYTH STREET
1,
44 plrlo ATLANTA, GEORGIA 30303-8960
Mr. Mark McIntire
North Carolina Department of Environment and
Natural Resources
Division of Water Quality
NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
SUBJ: Draft NPDES Permit Modification
Roanoke Rapids WWTP
Permit No. NC0024201
. 2005
t ,AR 2 4 2005
. •Jti.Jaa'0.�ww�!✓.lT`.�iCwYJ'4 a�MjfM..r a.. -aye,..'
g W1
MAR 3 1 2005
DENR - W\TEn QUhLITY
POINT SOURCE BRANCH
Dear Mr. McIntire:
In accordance with the EPA/NCDENR MOA, we have completed review of the draft
permit modification referenced above and have no comments. We request that we be afforded an
additional review opportunity only if significant changes are made to the draft permit modification
prior to issuance or if significant comments objecting to it are received. Otherwise, please send us
one copy of the final permit when modified.
Sincerely,
Marshall Hyatt, Environmental Scientist
Permits, Grants, and Technical Assistance Branch
Water Management Division
Internet Address (URL) • http://www.epa.gov
Recycled/Recyclable • Printed with Vegetable OH Based Inks on Recycled Paper (Minimum 30% Postconsumer)

AFFIDAVIT OF PUBLICATION
State of North Carolina
County of Durham
Teresa Ellis being duly sworn says that she is the Principal Clerk of
The Durham Herald Co., Inc., publishers of The Herald -Sun a newspaper published in
and of general circulation in said County, and that a notice of which the annexed is a
true copy, was published in said newspaper one time on the 26th day of March, 2005.
l,(
Principal Clerk
Sworn to and subscribed before me this 1st day of April, 2005.
(LiikarY ublic
My commission expires December 16, 2006.
Durham County, North Carolina
4. Cross examination of
persons presenting tes-
timony will not be al-
lowed; however, the ,
hearing officer may ask '
questions for
clarification.
5. The hearing record
may be closed at the
conclusion of the
meeting.
WHEN: April 28, 2005
at 7:00 p.m.
WHERE: City of Oxford
Public Works Building
227 W. McClanahan St.
Oxford, North Carolina
INFORMATION: A copy
of the draft SOC is avail-
able by writing or
calling:
Ms. Carolyn Bryant
NC Division of Water
Quality / Point Source
Branch
1617 Mail Service
Center
Raleigh, North Carolina
27699-1617
Telephone number:
[phone],
extension 520
The applications and
other information are
on file at the Division of
Water Quality's Raleigh
Regional Office (3800
Barrett Drive, Raleigh,
North Carolina). They
may be inspected dur-
ing normal office hours.
Copies of the informa
Son on file are available
upon request and pay-
ment of the costs of re-
production. All such
comments and re-
quests regarding this
matter should make ref-
erence to the permit
number(s) listed above.
H-S: March 26, 2005
, 11111///1.
``
NOTICE OF
PUBLIC HEARING
TO BE HELD BY
THE NORTH CAROLINA
ENVIRONMENTAL
MANAGEMENT
COMMISSION
ON INTENT TO ISSUE
A SPECIAL ORDER
BY CONSENT
SUBJECT: A public hear-
ing has been scheduled
concerning the pro-
Sosed issuance of a
pec al Order by Con-
sent (SOC) for the fol-
lowing NPDES permit-
ted facility:
Permit number
NC0025054, City of Ox-
ford WWTP. This facility
discharges to Fishing
Creek, a class C-NSW
water in the Tar -
Pamlico River Basin.
PURPOSE:This appli-
cant has applied for
coverage under a Spe-
cial Order by Consent.
On the basis of prelimi-
nary staff review, the Di-
vision proposes to is-
sue a SOC for this facili-
ty. The Director of the
Division of Water Quali-
ty pursuant to NCGS
143-215.1(c) (3) and Reg-
ulation 15 NCAC 2H,
Section .0100 has deter-
mined that it is in the
public interest that a
meeting be held to re-
ceive all pertinent pub-
lic comment on wheth-
er to issue, modify, or
deny the SOC.
PROCEDURE:The hear-
ing will be conducted in
the following manner:
1.An explanation of the
North Carolina Environ-
mental Management
Commission's SOC pro-
cedure will be present-
ed by the Division of
Water Quality.
2.An explanation of the
action for which the
SOC is requested may
be made by the
pplicant.
ti '�;• • �'y • Public C
omment -
a hQ' / () Comments,
state-
►..i merits, data and other
information may be sub-
r��a miffed in writing prior to
� 0 : N .d or during tile meeting
. ��� J or maybe presentedpoor
�/ ally at the meeting.
/ •....-•• t sons desiring to speak
//// D ••��i1� will indicate this intent
'/1lll l lilt%OS% eon at tthe mef et rig. So
that a0 persons desiring
to speak may
lengthy statements
may be limited at the
meet-
ing officer. Oral presen-
tations that exceed
three minutes should
be accompanied by
three written copies,
which will be filed with
Division
t
isionstaff
at the time

Copies of the draft
permit and other sup-
porting information on
file used to determine
conditions present in
the draft permit are
available upon re-
quest and payment of
the costs of reproduc-
tion, Mail comments
and/or requests for in-
formation to the NC
Division of Water
Quality at the above
address or call the
Point Source Branch
at [phone], ex-
tension 520. Please
include the NPDES
permit number (at-
tached) in any com-
munication. Interested
persons may also visit
the, ,Division of Water
Quality at 512 N. Sal-
isbury Street, Raleigh,
NC 27604-1148 be-
tween the hours of
8:00 a.m. and 5:00
p.m. to review infor-
mation on file.
The Roanoke Rapids
Sanitary District has
applied for modifica-
tion the NPDES per-
mit (NC0024201) for
its sanitary wastewa-
ter treatment plant lo-
cated in Weldon, NC,
Halifax County. This
has historically dis-
charged to Chock-
oyotte Creek but has
completed a reloca-
tion to the Roanoke
River mainstem and
will commence dis-
charge to the Roa-
noke River in the near
future. This modifica-
tion is a change to the
total mercury limita-
tion imposed at the
Roanoke River outfall
and is based on in -
stream data collected
by the facility during
the previous 12 month
period. Currently, total
mercury, total fluoride,
and total selenium are
water quality limited_
This discharge may
impact future alloca-
tions in either Chock-
oyotte Creek or the,
Roanoke River.
March 20; 2005

PUBLIC NOTICE
STATE OF NORTH
CAROLINA
ENVIRONMENTAL
MANAGEMENT
COMMISSON/
NPDES UNIT
1617 MAIL SERVICE
CENTER RALEIGH,
NC 27699-1617
NOTIFICATION OF
INTENT TO
ISSUE A NPDES
WASTEWATER
PERMIT
AFFIDAVIT OF PUBLICATION
ROANOKE RAPIDS
DAILY AND SUNDAY HERALD
ROANOKE RAPIDS, NC 27870
On the basis of thor- To: NCDENR/DWQ/NPDES
ough staff review and Attn: Carolyn Bryant
application of NC 1617 Mail Service Ct.
GeneralStatute
143.21,Public law92- g Ralei h� NC 27699-1617
law
500 and other lawful --
standards and regula-
tions, the North Caroli- Date Description Amount
na Environmental Waste Water Permit
Management Com-
mission proposes to
issue a National Pollu March 20 16" @ $9.90 $158.40
tant Discharge Elimi-
nation • System
(NPDES) wastewater BILLS DUE AFTER FIRST INSERTION TO INSURE REQUIRED NUMBER OF PUBLICATIONS —
discharge permit to ATTORNEYS PLACING ADVERTISING ARE RESPONSIBLE FOR ACCOUNTS.
the person(s) listed
below . effective 45
days from the publish AFFIDAVIT OF PUBLICATION
date of this notice. North Carolina
Written comments re- Halifax County
garding the proposed
permit will be accept- Before the undersigned, a Notary Public of said County and State, duly commissioned,
ed until 30 days after qualified, and authorized by law to administer oaths, personally appeared Cathy C. Pruitt
the publish date of who beingfirst dulysworn, deposes and says: that he/she is Asst. Bookkeeper.
this notice. All com-
ments received prior (Owner, partner, publisher, or other officer or employee authorized to make this affidavit) of
to that date are con- THE ROANOKE RAPIDS HERALD engaged in the publication of a newspaper known as
sidered in the final de- DAILY AND SUNDAY HERALD, published, issued, and entered as second class mail in the
terminations regarding City of Roanoke Rapids in said County and State; that he/she is authorized to make this
the proposed permit. • affidavit and sworn statement; that the notice or other legal advertisement, a true copy of
The Director of the which is attached hereto, was published in THE DAILY AND SUNDAY HERALD on the
NC Division of Water following dates:
Quality may decide to g
hold a public meeting March 20,_2005
for the proposed per-
mit should the Divi-
sion receive a signifi-
cant degree of public
interest.
PAID
•/7/05--
and that the said newspaper in which such notice, paper, document, or legal advertisement was
published, at the time of each and every such publication, a newspaper meeting all of the
requirements and qualifications of Section 1-597 of the General Statutes of North Carolina and
was a qualified newspaper within the meaning of Section 1-597 of the Ge al Statutes of
North Carolina.
Signed ��� �'• ,A.i_C�C�
Assistant Bookkeeper
Subscribed and sworn to before me this March 25, 2005.
%wooly
49
My cimmission expires
(SEAL)
ft64 20X0 NOTARY PUBLIC

Mac 18 05 11:18a
• NC 27604-1148 be-
tween the hours of
8:C0 a.m. and 5:00
p.m. to review infor-
mation on file.
The Roanoke Rapids
Sanitary District has
applied for modifica-
tion the NPDES per-
mit (NC0024201) for
its sanitary wastewa-
ter treatment plant lo-
cated in Weldon, NC,
Halifax County. This
has historically dis-
charged to Chock
oyottte Creek but has
completed a reloca-
tion to the Roanoke
River mainstem and
will commence dis-
charge to the Roa-
noke River in the near
future. This modifica-
tion is a change to the
total mercury limita-
tion imposed at the
Roanoke River outfatl
and is based on in -
stream data collected
by the fadtlty during
the previous 12 month
period. Currently, total
mercury, total fluoride,
and total selenium are
water quality limited.
This discharge may
impact future alloca-
tions in either Chock-
oyotte Creek or the
Roanoke River.
March 20; 2005
DAILY HERALD
2525375411 p.3

Mar 18 05 1 1 : 18a DAILY HERALD
/ w/VLIV /YV 1 IVL.
STATE OF NORTH
CAROLINA
ENVIRONMENTAL
MANAGEMENT
COMMISSON/
NPDES UNIT
1617 MAIL SERVICE
CENTER RALEIGH,
NC 27699-1617
NOTIFICATION OF
INTENT TO
ISSUE A NPDES
WASTEWATER
PERMIT
On the basis of thor-
ough staff review and
application of NC
General Statute
143.21, Public law 92-
500 and other lawful
standards and regula-
tions, the North Caroli-
na Environmental
Management Com-
mission proposes to
issue a National Pollu-
tant Discharge Elimi-
nation System
(NPDES) wastewater
discharge permit to
the person(s) listed
below effective 45
days from the publish
date of this notice.
Written comments re-
garding the proposed
permit will be accept-
ed until 30 days after
the publish date of
this notice. All com-
ments received prior
to that date are con-
sidered in the final de-
terminations regarding
the proposed permit
The Director of the
NC Division of Water
Quality may decide to
hold a public meeting
for the proposed per-
mit should the Divi-
sion receive a signifi-
cant degree of public
interest.
Copies of the draft
permit and other sup-
porting information on
file used to determine
conditions present in
the draft permit are
available upon re-
quest and payment of
the costs of reproduc-
tion. Mail comments
and/or requests for in-
formation to the NC
Division of Water
Quality at the above
address or call the
Point Source Branch
at [phone], ex-
tension 520. Please
include the NPDES
permit number (at-
tached) in any com-
munication. Interested
persons may also visit
the Division of Water
Quality at 512 N. Sal-
2525375411 p.2 •
I "I

Roanoke Rapids Sanitary District
March 4, 2005
Mr. Mark McIntire
NPDES Unit, Division of Water Quality
1617 Mail Service Center
Raleigh, North Carolina, 27699-1617
RE: Request for Permit Modification
NPDES Permit No. NC0024201
Dear Mr. McIntire,
P.O. Box 308
1000 Jackson Street
Roanoke Rapids, NC 27870
[phone]
Fax: [phone]
www.rrsd.org
-.-t.:..::NOs.Yry MwlP.1.a:::T!ZY:'fYiC.+3l'jjT�..�l•Y�f...:; :. - -
MAR 1 7 2005
DENR - WATER QUALITY
POINT SOURCE BRANCH
The Roanoke Rapids Sanitary District (RRSD) is in the process of relocating our existing outfall from
the Chockoyotte Creek to the Roanoke River, effective June 1, 2005. Our outfall relocation will
discharge into a portion of the Roanoke River that was placed on the 303d list in 2002 for mercury due to
fish advisories. Per the 303d list, the source of mercury in the Roanoke River is believed to be
atmospheric deposition. As a result of the outfall relocation, the mercury limit in our current National
Pollutant Discharge Elimination System (NPDES) permit was set equal to the water quality standard of
12 ng/1. This mercury limit was based on an Environmental Protection Agency (EPA) policy for a
pollutant of concern in 303d listed streams.
Our NPDES permit requires that background concentrations of mercury in the Roanoke River be taken
upstream of the proposed outfall location. Additionally, our NPDES permit contains a metals re -opener
clause that states that after 12 months of sampling and monitoring, the RRSD may request a modification
of the effluent limitations and upstream monitoring for metals (Condition A(7)). Correspondence from
the Environmental Protection Agency (EPA) supports this clause in our NPDES permit, per a letter dated
March 2003 stating:
"We note that the discharge may be relocated to the Roanoke River and the
background mercury sampling is being required If reasonable potential to exceed
the State's numeric mercury criterion exists at the time of relocation, River
background mercury levels must demonstrate the lack of impairment before any
credit for dilution using the critical low flow of the Roanoke River can be given."
We have been collecting mercury samples upstream of our proposed outfall to the Roanoke River from
October 2003 to the present time. This monitoring data is provided in Table 1. The background
concentrations of mercury in the Roanoke River are 50 to 90 percent below the water quality standard.
Therefore, we feel that credit should be given in our NPDES permit for dilution in the Roanoke River.
Our proposed outfall relocation will not contribute to the impairment status of the river.
We also performed a reasonable potential analysis (RPA) on our effluent mercury data, and the
maximum predicted effluent concentration is an order of magnitude less than the allowable stream
econtsts adsings \&IV dnt1151140espmnt4ndlerm+relW'gr
Page:
1/2

concentration. Therefore, we feel that a monitoring requirement, in lieu of a limit, is a more appropriate
permit condition.
Table 1: Roanoke Rapids Sanitary District Mercury Sampling Data
Influent Effluent % Removed in Upstream River
Date Conc., ng/l Conc., ng/l WWTP Conc., ng/1
October 2003 8.1 1.53
November 2003 19.0 1.48
December 2003 17.2 2.15
January 2004 40.0 1.90
February 2004 12.8 2.10
March 2004 8.4 3.76
April 2004 16.0 1.07
May 2004 8.1 4.46
June 2004 29.8 2.75
July 2004 249.0 21.3 91% 2.75
August 2004 30.2 14.8 51% 4.38
September 2004 86.0 17.2 80% < 1.00
October 2004 75.7 34.0 55%
November 2004
December 2004
In summary, the RRSD respectfully requests that our NPDES permit be re -opened to modify/remove the
effluent mercury limit for a discharge to the Roanoke River via credit for stream dilution. We have met
the sampling and monitoring requirements of our permit, and our data shows that our relocated outfall
will not contribute to impairment of the river.
We very much appreciate the time and effort of the NPDES Unit to consider the re -opening of our permit
to address this mercury issue. We thank you for your consideration of this request and we look forward
to your response. We would be happy to provide additional information or to meet with you to clarify
the issues. Please do not hesitate to call myself or Mary Sadler with ARCADIS (770-431-8666) if you
have any questions.
Sincerely,
Roanoke Rapids Sanitary District
R. Danieley Brow17 P.E.
Chief Executive Officer
Cc: Gregg Camp, ORC RRSD Wastewater Treatment Plant
Marshall Hyatt, EPA Region 4
Dave Goodrich, DWQ, NPDES Unit Supervisor
Mary Sadler, ARCADIS
NPDES Unit File — 2
File
\do w..lmidoc
Page:
2/2

Roanoke Rapids Sanitary District
March 4, 2005
Mr. Mark McIntire
NPDES Unit, Division of Water Quality
1617 Mail Service Center
Raleigh, North Carolina, 27699-1617
RE: Request for Permit Modification
NPDES Permit No. NC0024201
Dear Mr. McIntire,
P.O. Box 308
1000 Jackson Street
Roanoke Rapids, NC 27870
[phone]
Fax: [phone]
www.rrsd.org
The Roanoke Rapids Sanitary District (RRSD) is in the process of relocating our existing outfall from
the Chockoyotte Creek to the Roanoke River, effective June 1, 2005. Our outfall relocation will
discharge into a portion of the Roanoke River that was placed on the 303d list in 2002 for mercury due to
fish advisories. Per the 303d list, the source of mercury in the Roanoke River is believed to be
atmospheric deposition. As a result of the outfall relocation, the mercury limit in our current National
Pollutant Discharge Elimination System (NPDES) permit was set equal to the water quality standard of
12 ng/l. This mercury limit was based on an Environmental Protection Agency (EPA) policy for a
pollutant of concern in 303d listed streams.
Our NPDES permit requires that background concentrations of mercury in the Roanoke River be taken
upstream of the proposed outfall location. Additionally, our NPDES permit contains a metals re -opener
clause that states that after 12 months of sampling and monitoring, the RRSD may request a modification
of the effluent limitations and upstream monitoring for metals (Condition A(7)). Correspondence from
the Environmental Protection Agency (EPA) supports this clause in our NPDES permit, per a letter dated
March 2003 stating:
"We note that the discharge may be relocated to the Roanoke River and the
background mercury sampling is being required. If reasonable potential to exceed
the State's numeric mercury criterion exists at the time of relocation, River
background mercury levels must demonstrate the lack of impairment before any
credit for dilution using the critical low flow of the Roanoke River can be given."
We have been collecting mercury samples upstream of our proposed outfall to the Roanoke River from
October 2003 to the present time. This monitoring data is provided in Table 1. The background
concentrations of mercury in the Roanoke River are 50 to 90 percent below the water quality standard.
Therefore, we feel that credit should be given in our NPDES permit for dilution in the Roanoke River.
Our proposed outfall relocation will not contribute to the impairment status of the river.
We also performed a reasonable potential analysis (RPA) on our effluent mercury data, and the
maximum predicted effluent concentration is an order of magnitude less than the allowable stream
oldsriasrdse comtnstIsermlnmiznbuottic
Page:
1/2

concentration. Therefore, we feel that a monitoring requirement, in lieu of a limit, is a more appropriate
permit condition.
Table 1: Roanoke Rapids Sanitary District Mercury Sampling Data
Influent Effluent % Removed in Upstream River
Date Conc., ng/I Conc., ng/1 WWTP Conc., ng/1
October 2003 8.1 1.53
November 2003 19.0 1.48
December 2003 17.2 2.15
January 2004 40.0 1.90
February 2004 12.8 2.10
March 2004 8.4 3.76
Apri12004 16.0 1.07
May 2004 8.1 4.46
June 2004 29.8 2.75
July 2004 249.0 21.3 91% 2.75
August 2004 30.2 14.8 51% 4.38
September 2004 86.0 17.2 80% < 1.00
October 2004 75.7 34.0 55%
November 2004
December 2004
In summary, the RRSD respectfully requests that our NPDES permit be re -opened to modify/remove the
effluent mercury limit for a discharge to the Roanoke River via credit for stream dilution. We have met
the sampling and monitoring requirements of our permit, and our data shows that our relocated outfall
will not contribute to impairment of the river.
We very much appreciate the time and effort of the NPDES Unit to consider the re -opening of our permit
to address this mercury issue. We thank you for your consideration of this request and we look forward
to your response. We would be happy to provide additional information or to meet with you to clarify
the issues. Please do not hesitate to call myself or Mary Sadler with ARCADIS (770-431-8666) if you
have any questions.
Sincerely,
Roanoke Rapids Sanitary District
R. Danieley Browgl, P.E.
Chief Executive Officer
Cc: Gregg Camp, ORC RRSD Wastewater Treatment Plant
Marshall Hyatt, EPA Region 4
Dave Goodrich, DWQ, NPDES Unit Supervisor
Mary Sadler, ARCADIS
NPDES Unit File — 2
File
Odo umis rind seengsdalrtydanets\ p es pmri4ndpom rtapnrgm{dc
Page:
2/2

S
ROANOKE RAPIDS SANITARY DISTRICT
Permit No. NC0024201
Preliminary Strategies for Mercury Limit Compliance
Issue:
• The RRSD Wastewater Treatment Plant (WWTP) has a NPDES permit limit for mercury set
at the water quality standard of 12 ng/1 for the Roanoke River.
• Major portions of the Roanoke River were placed on the 303d list in 2002 for mercury due to
fish advisories. Per the 303d list, the source of mercury in the Roanoke River is believed to
be atmospheric deposition.
• The new mercury limit was determined based on a Division of Water Quality (DWQ) policy
for a pollutant of concern in 303d listed streams.
• The RRSD will have difficultly meeting the new mercury limit once the outfall relocation is
complete and hence will be in violation of the existing NPDES permit limit. The mass
balance for mercury at the RRSD WWTP is as follows:
Influent
Date Conc., ng/1
October 2003
November 2003
December 2003
January 2004
February 2004
March 2004
April 2004
May 2004
June 2004
July 2004 249.0
August 2004 30.2
September 2004 86.0
October 2004 75.7
Effluent % Removed
Conc., ng/1 in WWTP
8.1
19.0
17.2
40.0
12.8
8.4
16.0
8.1
29.8
21.3 91%
14.8 51%
17.2 80%
34.0 55%
Upstream
Conc., ng/1
1.53
1.48
2.15
1.90
2.10
3.76
1.07
4.46
2.75
2.75
4.38
< 1.00
Downstream
Conc., ng/1
1.10
1.43
2.24
2.02
5.04
1.31
1.60
2.58
< 1.00
1.58
1.18
< 1.00
Possible Solution: A Variance for Mercury in the NPDES Permit in Lieu of a
Special Order by Consent (SOC)
• A TMDL for mercury in the Roanoke River Basin has not been implemented. A variance
will provide the RRSD with temporary relief from the standard by establishing a limit for
mercury based on the variance until TMDL development.
• Water quality variances must be supported under 40 CFR 131.10(g), whereby the State
believes that the standard may ultimately be attained or is unsure about the ultimate
attainment of the standard.
• A variance may only be granted after implementation of effluent controls show that the water
quality standard cannot be attained by the permittee and that the lowest possible level of
mercury has been reached by the permittee.
AS
Nod -

ROANOKE RAPIDS SANITARY DISTRICT
Permit No. NC0024201
Preliminary Strategies for Mercury Limit Compliance
General Variance Request:
Specific guidance has been developed in EPA Region 5 for POTWs requesting a variance for
mercury (Draft Mercury Pollutant Minimization Program Guidance, July 2004, U.S. EPA
Region 5 NPDES Programs Branch).
Pollution Prevention Plan
1. Demonstration of QA/QC procedures in the current mercury sampling and analysis
program.
2. Identification (if feasible) of the source of mercury in the WWTP influent.
a. Frequent evaluation of mercury from Significant Industrial User (SIU) waste streams.
b. Sampling and evaluation to determine domestic sources of mercury.
3. Development and implementation of mercury reduction communication strategies to the
public sector (e.g. targeting potential domestic sources of mercury).
Economic Analysis
1. High level cost analysis to implement advanced technologies for mercury reduction.
Proposed Schedule with Variance Request
1. Source evaluation. •
2. Identification of potential reduction, elimination, and prevention methods.
3. Status and progress updates.

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