HomeMy WebLinkAboutNC0037834_Permit (Issuance)_19990712NPDES DOCIMENT :SCANNING; COVER SHEET
NC0037834
Archie Elledge WWTP
NPDES Permit:
Document Type: '
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Correspondence
Owner Name Change
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
July 12, 1999
This document is printed on reuse paper - igiiore any
content on the reverse 'side
State of North Carolina
Department of Environment
and Natural Resources
Divisin.n of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
Kerr T. Stevens, Director
July 12, 1999
Mr. Thomas W. Griffin, Assistant City Manager
City of Winston-Salem
Post Office Box 2511
Winston-Salem, North Carolina 27102
Dear Mr. Griffin:
AVA
NCDENR
NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL. RESOURCES
Subject: NPDES Permit Issuance
Permit Number NC0037834
Archie Elledge WWTP
Forsyth County
In accordance with the application for discharge permit received on February 3, 1998, the
Division is forwarding herewith the subject state - NPDES permit. This permit is issued pursuant to
the requirements of North Carolina General Statute 143-215.1 and the Memorandum of Agreement
between North Carolina and the U.S. Environmental Protection Agency dated December 6, 1983.
In accordance with your comments on the draft NPDES permit received on June 3. 1999,
the following modifications have been made:
• The "Supplement to Permit Cover Sheet" has been corrected to accurately reflect all
active treatment components;
• The total cyanide quantitation level has been clarified as a footnote on effluent page A(1):
• Footnote 3 regarding dissolved oxygen has been clarified in accordance with your request;
• The instream monitoring footnote on effluent page A(1) has been corrected to accurately
reflect the locations of upstream and downstream sampling locations: and -
• Condition A(2) has been modified to address your May 24, 1999 comment. Although the
toxicity testing language has been modified to indicate that compliance is currently based
on a quarterly average. in the near future compliance will be based on individual sample
events while an average will be used for assessing civil penalties.
If any parts, measurement frequencies or sampling requirements contained in this permit are
unacceptable to you, you have the right to an adjudicatory hearing upon written request within thirty
(50) days following receipt of this letter. This request must be in the form of a written petition,
conforming to Chapter 150B of the North Carolina General Statutes, and filed with the office of
1617 MAIL SERVICE CENTER, RALEIGH, NORTH CAROLINA 27699-1617 - TELEPHONE 919-733-5083/FAX 919-733-0719
AN EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER - 50% RECYCLED/ 10% POST -CONSUMER PAPER
a
Administrative Hearings, Post Office Drawer 27447, Raleigh, North Carolina 2761 1-7447. Unless
such a demand is made, this permit shall be final and binding.
r-
This permit does not affect the legal requirements to obtain other permits which may be
required by the Division of Water Quality or permits required by the Division of Land Resources,
Coastal Area Management Act, or any other Federal or Local governmental permits which may be
required.
If you have any questions or comments regarding these speculative limitations, please do not
hesitate to contact Mark McIntire at telephone number (919) 733-5083, extension 553.
Sincerely
Original Signed BY
David A. Goodrich
Kerr T. Stevens
Cc: Central Files
NPDES Permit File
Winston-Salem Regional Office, Water Quality
Aquatic Toxicology Unit
EPA, Roosevelt Childress
Point Source Compliance/Enforcement Unit
Permit No. NC0037834
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
E
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended,
City of Winston-Salem
is hereby authorized to discharge wastewater from a facility located at
Archie Elledge Wastewater Treatment Plant
On NCSR 2972 (Griffith Road)
Southwest of Winston-Salem
Forsyth County
to receiving waters designated as Salem Creek in the Yadkin -Pee Dee River Basin
in accordance with effluent limitations, monitoring requirements, and other conditions set forth in
Parts I, II, III and IV hereof.
This permit shall become effective August 1, 1999
This permit and authorization to discharge shall expire at midnight on June 30, 2004.
Signed this day July 12, 1999
Original Signed By
David A. Goodrich
Kerr T. Stevens, Director
Division of Water Quality
By Authority of the Environmental Management Commission
i)
Permit No. NC0037834
SUPPLEMENT TO PERMIT COVER SHEET
City of Winston-Salem
is hereby authorized to:
1. Continue operation of an existing 30.0 MGD wastewater treatment system consisting of
mechanical screening and grit removal, primary clarification, aeration basins, final clarification,
sodium hypochlorite and bisulfite feed for disinfection and dechlorination, two centrifuges with
screw conveyors, sludge digestion, polymer and iron salt feed facilities, an odor control system,
and instrumented flow measurement located at the Archie Elledge Wastewater Treatment Plant on
Griffith Road, Southwest of Winston-Salem in Forsyth County; and
2. Discharge from said treatment works at the location specified on the attached map into Salem
Creek which is classified C waters in the Yadkin -Pee Dee River Basin.
J 1 _
Latitude: I 36°Ol'04"
Longitude: 80°18'S4"
Ouad #: C17SE
Stream Class: C
Receiving Stream: Salem Creek
Permitted Flow: 30.0 MGD
It
City of Winston-Salem
NC0037834
Archie Elledge Wastewater Treatment Plant
A (1). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS - FINAL
Permit No. NC0037834
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge from outfall(s) serial number 001-
Wastewater Treatment Plant Effluent. Such discharges shall be limited and monitored by the Permittee as specified below:
':AFFLUENT' CHARACT S� bICS : ``'
�� �,. rr
ILt
DISCHARGE LIMITATIONS �
MONITORIN�REQLIIREMEN'I�S� ;,
f,'.sf+ -1 S'f
?.. rit'M.,: µ'k
.- _
�� xr_
_ .,i
inthl !. �
Y �--
��e ~..' F
r,sti�3
fiii t i'
�:. Averages
-!^ a`t.
.\ i �.d
-.) W :,
a,�. �Y,z
`.'. i': ,.ts:.,.; x>t �
(►i-.,;j'�
r,'` : i,+
''- Average � �..�
may,; j.::fl. yf B
`�TCP �,5: ?v
�: D ?►�Y. .�
$✓d• �
"�alx.�
y i
Maximum ..
:r ,. ..�.
-� Effluent urem
i ;
�ns!�
� , .y. , Frequeri �
,a..: ~p
S �'le 1 t
a:rl .�°
,,�;��•.
-..s•.r —. ,
'T� •'fx•
ample
-Z rig
{I:ooa►fxon i ri
Flow (MGD)
30.0
Continuous
Recording
1 or E
BOD, 5-Day, 20°C (April 1 — October 31)2
21.0 mg/L
31.5 mg/L
Daily
Composite
I, E, U, D
BOD, 5-Day, 20°C (November 1 — March 31)2
30.0 mg/L
45.0 mg/L
Daily
Composite
1, E, U. D
Total Suspended Residue'
30.0 mg/L
45.0 mg/L
Daily
Composite
I. E
NH3 as N (April 1 — October 31)
1.2 mg/L_
Daily
Composite
E, U, D
NH3 as N (November 1 — March 31)
'9.0 mg/L
Daily
Composite
E, U, D
Dissolved Oxygen'
Daily
Grab
E, U, D
Fecal Coliform (geometric mean)
200/100 ml
400/100 ml
Daily
Grab
E. U. D
Total Residual Chlorine
• Daily
Grab
E
Temperature
Daily
Grab
E. U. D
Conductivity
Monthly
Grab
E. U, D
Total Phosphorus
Weekly
Composite
E
Total Nitrogen (NO2+NO3+TKN)
Weekly
Composite
' E
pH4
Daily
Grab
E
Cadmium
2/Month
Composite
E
Cyanides
6.6 ug/L
26.0 ug/L
Weekly
Grab
E
Zinc
2/Month .
Composite
E
Copper
`
2/Month
Composite
E
Chronic Toxicity'
Quarterly
Composite
E
OTES:
Sample Locations: I — Influent, E — Effluent, U — Upstream, Salem Creek 1300 feet above NCSR 112. D - Downstream (1) Salem Creek at NCSR 2991. (2) Muddy Creek at
NCSR 1493, and (3) Muddy Creek at NCSR 1485; Upstream and downstream samples shall be grab samples collected 3/Week during the months of June, July. August. and
September and Weekly during the remainder of the year with the exception of BOD, NH3-N, and conductivity. BOD and NH3-N instream samples shall be collected weekly and
conductivity samples monthly. Instream monitoring is provisionally waived in light of the permittee's participation in the Yadkin -Pee Dee River Basin Association. lnstream
monitoring will be immediately reinstated should the permittee end its participation in the Association.
2 The monthly average effluent BOD5 and total suspended residue concentrations shall not exceed 15% of their respective influent values (85% removal).
3 The daily average effluent dissolved oxygen concentration shall not be less than 6.5 mg/L.
4 The pH shall not be less than 6.0 standard units or greater than 9.0 standard units.
5
6
The detection level for cyanide shall be 20 µg/L. Should -the measurement for total cyanide be less than the detection level, the quantity for purposes of compliance evaluation is
considered to be zero.
Toxicity (Ceriodaphnia) ChV @ 76%; January, April. July, and October; See condition A(2) of this permit.
THERE SHALL BE NO DISCHARGE OF FLOATING SOLIDS OR VISIBLE FOAM IN OTI IER THAN TRACE AMOUNTS.
Permit No. NC0037834
SUPPLEMENT TO EFFLUENT LIMITATIONS
AND MONITORING REQUIREMENTS
SPECIAL CONDITIONS
A (2). CHRONIC TOXICITY PERMIT LIMIT (QUARTERLY) — 30.0 MGD
The permittee shall conduct chronic toxicity tests using test procedures outlined in the "North Carolina Phase
I1 Chronic Whole Effluent Toxicity Test Procedure" (Revised -November 1995) or subsequent versions.
The effluent concentration defined as the Instream Waste Concentration (IWC) shall be 76%. The chronic
value will be determined using the geometric mean of the highest concentration having no detectable
impairment of reproduction or survival and the lowest concentration that does have a detectable impairment of
reproduction or survival. The presence of 48 hour acute toxicity will be determined using Fisher's Exact Test
at 48 hours from test initiation. The definition of "detectable impairment," collection methods, exposure
regimes, and further statistical methods are described by the document referenced above.
The permit holder shall perform at a minimum, quarterly monitoring using these procedures to establish
compliance with the permit condition. The tests will be performed during the months of 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 measures 48 hour acute toxicity or a
chronic value less than that specified above, then multiple concentration testing shall be performed, at a
minimum, in each of the two following months. Compliance is defined as a quarterly average chronic effect
level equal to or greater than 76%.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code THP3B for
the Chronic Value and TGA3B for the 48 hour Acute Toxicity measure (Pass/Fail). Additionally, DWQ Form
AT-3 (original) is to be sent to the following address:
Attention: Environmental Sciences Branch
North Carolina Division of
Water Quality
4401 Reedy Creek Road
Raleigh, NC 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total.residual chlorine of
the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the waste
stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required.
the permittee will complete the information located at the top of the aquatic toxicity (AT) test form indicating
the facility name, permit number, pipe number, county, and the month/year of the report with the notation of
"No Flow" in the comment area of the form. The report shall be submitted to the Environmental Sciences
Branch at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, then monthly
monitoring will begin immediately until such time that a valid test is submitted. Upon submission of a valid
test, this monthly test requirement will revert to quarterly in the months specified above.
•
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of
Water Quality indicate potential impacts to the receiving stream, this permit m1.y be re -opened and modified to
include alternate monitoring requirements or limits. t -
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 Iater than the last day
of the month following the month of the initial monitoring.
CITY OF WISTOSALEI
PUBLIC WORKS DEPARTMENT
PO. BOX 2511 • WINSTON-SALEM, NORTI I CAROLINA 27102-2511
May 24, 1999
Mr. Mark McIntire
Division of Water Quality
Department of Environment and
Natural Resources
P.O. Box 29535
Raleigh, North Carolina 27626-0535
Ii
OENR - WATER QUALITY
POINT SOURCE BRANCH
Subject: Comments on Draft NPDES Permit
Archie Elledge WWTP (NC0037834)
City of Winston-Salem; Forsyth County
Dear Mr. McIntire:
Winston-Salem wishes to offer the following comments and concerns regarding the Draft NPDES
Permit for our Archie Elledge WWTP:
— The "Supplement to Permit Cover Sheet" contains reference to a treatment train containing
trickling filters and surge basins. These structures were demolished as a part of our last
plant upgrade and they should not be included in item #1 of this sheet.
— Although the cover letter accompanying the draft permit contains a reference to the 20
ppb quantitation limit for total cyanide, the page of "Effluent Limitations and Monitoring
Requirements" does not contain any language which incorporates this provision into the
actual permit.
Winston-Salem asks that the final permit include a footnote to the limits page stipulating
that; "If the measurement for total cyanide is below detection limits, the quantity for
purposes of compliance evaluation is considered to be zero. The current detection limit
for Cyanide shall be considered 20.0 micrograms per liter. Cyanide detected at levels less
than the detection limit shall be reported on the DMR to be <20.0 ppb".
— Footnote #3 on the monitoring and limits page contains language that appears to
contradict the daily average provision of the effluent dissolved oxygen limit. This provides
that "The daily average effluent dissolved oxygen concentration shall at no time be less
than 6.5 mg/I".
Mr. Mark McIntire
May 24, 1999
Page 2
Winston-Salem feels that the phrase "at no time" could be interpreted to mean that a
violation would occur if the instaneous average of the dissolved oxygen readings taken
previously during the day drops below 6.5 mg/1. We ask that the text of the footnote as it
appears in our current permit be used.. This provision should state that; "The daily
average dissolved oxygen effluent concentration shall not be less than 6.5 mg/1".
— The Effluent Limitations sheet stipulates that the plant's upstream sample site shall be at
Meadowbrook Lane and that the downstream site shall be at U.S. 117. This appears to be
an error as there is no Meadowbrook Lane in Forsyth County and U.S. 117 runs north and
south through Fayetteville.
— Special Condition A(2) regarding chronic toxicity permit limitations does not clearly
stipulate what constitutes a permit violation. This language could be interpreted to mean
that a single test failure constitutes non-compliance.
Winston-Salem asks that the language in our existing permit defining compliance as a
quarterly average chronic effect level equal to or greater than the instead waste
concentration be incorporated into the new permit.
— The draft permit did not include any of the "Boiler Plate" documents. Winston-Salem
reserves the right to contest any of the stipulations contained in this section of the permit
should they be different than the requirements recently submitted to us with the draft
permit for our Muddy Creek WWTP (NC0050342).
Thank you for your consideration regarding this matter and please call me at 336-765-0130 if you
have any questions.
Stanley B. Webb
Wastewater Operations Superintendent
PC: David Saunders; Utility Plants Engineer
Ref:1052499a
6 fr
Division of Water Quality
May 14, 1999
MEMORANDUM
TO: Dave Goodrich
THROUGH: Matt Matthews N'''s
FROM: Kristie Robeson 1�Iv
SUBJECT: Draft Permit Corrections
Winston -Salem -Muddy Creek WWTP
NPDES Permit No. NC0050342
Forsyth County
Winston -Salem -Archie Elledge WWTP
NPDES Permit No. NC0037834
Forsyth County
Our office has received the draft permits for these subject facilities. The Special
Condition pages for these drafts contain incorrect language for Phase II chronic toxicity
testing. The paragraph which states, "If the test procedure performed as the first test of
any single quarter measures 48 hour acute toxicity or a chronic value less than that
specified above, then multiple concentration testing shall be performed, at a minimum, in
each of the two following months", was omitted in these drafts. Please find attached, a
copy of the correct chronic toxicity language to be used in these permits.
We appreciate your assistance to undertake the necessary steps to correct the
existing draft permits and incorporate the recommendation cited above. Please feel free:,
to contact me at 2136 if you have any questions. `°
w
CHRONIC TOXICITY PERMIT LIMIT (QRTRLY)
The effluent discharge shall at no time exhibit 48 hour acute toxicity as lethality in an effluent concentration
of % nor measure a quarterly arithmetic average chronic value less than this same percentage of waste.
The chronic value will be determined using the geometric mean of the highest concentration having no
detectable impairment of reproduction or survival and the lowest concentration that does have a detectable
impairment of reproduction or survival. The presence of 48 hour acute toxicity will be determined using
Fisher's Exact Test at 48 hours from test initiation. The definition of "detectable impairment," collection
methods, exposure regimes, and further statistical methods are specified in the "North Carolina Phase II
Chronic Whole Effluent Toxicity Test Procedure" (Revised -November 1995) or subsequent versions.
The permit holder shall perform at a minimum, quarterly monitoring using these procedures to establish
compliance with the permit condition. The tests will be performed during the months of
. Effluent sampling for this testing shall be performed at the NPDES permitted final
effluent discharge below all treatment processes.
t If the test procedure performed as the first test of any single quarter measures 48 hour acute toxicity or a
chronic value less than that specified above, then multiple concentration testing shall be performed, at a
minimum, in each of the two following months.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code THP3B
for the Chronic Value and TGA3B for the 48 hour Acute Toxicity measure (Pass/Fail). Additionally, DWQ
Form AT-3 (original) is to be sent to the following address:
Attention: Environmental Sciences Branch
North Carolina Division of
Water Quality
4401 Reedy Creek Road
Raleigh, North Carolina 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual chlorine of
the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the
waste stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is
required, the permittee will complete the information located at the top of the aquatic toxicity (AT) test
form indicating the facility name, permit number, pipe number, county, and the month/year of the report
with the notation of "No Flow" in the comment area of the form. The report shall be submitted to the
Environmental Sciences Branch at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this monthly
test requirement will revert to the schedule specified above.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of
Water Quality indicate potential impacts to the receiving stream, this permit may be re -opened and
modified to include alternate monitoring requirements or limits.
QPIIL Version 9/96
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 ljst . .
day of the month following the month of the initial monitoring.
QPIIL Version 9/96
State of North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
Kerr T. Stevens, Director
May 12. 1999
Mr. Thomas W. Griffin, Assistant City Manager
City of Winston-Salem
Post Office Box 2511
Winston-Salem, North Carolina 27102
Dear Mr. Griffin:
eVA
NCDENR
NORTH CAROLINA DEPARTMENT OF
ENVIRONMENT AND NATURAL RESOURCES
Subject: Draft NPDES Permit
Permit Number NC0037834
Archie Elledge WWTP
Forsyth County
The Division of Water Quality has completed the draft NPDES permit for the above
referenced facility. Significant modifications to the existing permit are noted below:
• In accordance with the Division's current strategy for permitting facilities discharging in
the Yadkin -Pee Dee River Basin, the monitoring frequency for total nitrogen and total
phosphorus has been increased from monthly to weekly.
• The limitation for cadmium has been eliminated as reasonable potential for a standard
violation does not exist. Additionally, the monitoring frequency for cadmium has been
decreased from weekly to 2/month.
• Instream monitoring requirements have been provisionally waived in light of the
permittee's participation in the Yadkin -Pee Dee River Basin Association (the
Association). Should participation in the Association be terminated. instream monitoring
requirements will be immediately reinstated as outlined on page A(1), Effluent
Limitations and Monitoring Requirements for outfall 001.
• Color monitoring has been deleted.
The quantitation level for cyanide remains 20 ,ug/L in accordance with the results of the
cyanide study completed in conjunction with the existing permit.
Intent to issue the attached draft NPDES permit will be published in a newspaper local to the
Winston-Salem area on or before May 19, 1999. Provided no significant adverse comment is
received, issuance of the permit will follow on July 7, 1999. Any comments on the draft permit
should be forwarded in writing to:
P.O. Box 29535, RALEIGH, NORTH CAROLINA 27626-0535 TELEPHONE 919-733-5083/FAX 919-733-0719
AN EQUAL OPPORTUNITY AFFIRMATIVE ACTION EMPLOYER 50% RECYCLED/ 10% POST -CONSUMER PAPER
Mark McIntire. NPDES Unit
Division of Water Quality
P.O. Box 29555
Raleigh, North Carolina 27626-0535
If you have any questions regarding the attached draft permit, please do not hesitate to
contact Mark McIntire at telephone number (919) 733-5085, extension 553.
r vid A. Goodrich
NPDES Supervisor
Cc: NPDES Permit File
EPA. Roosevelt Childress
Aquatic Toxicology Unit
Permit No. NC0037834
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 provision of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended,
City of Winston-Salem
is hereby authorized to discharge wastewater from a facility located at
Archie Elledge Wastewater Treatment Plant
On NCSR 2972 (Griffith Road)
Southwest of Winston-Salem
Forsyth County
to receiving waters designated as Salem Creek in the Yadkin -Pee Dee River Basin
in accordance with effluent limitations. monitoring requirements, and other conditions set forth in
Parts I. II, III and IV hereof.
This permit shall become effective
This permit and authorization to discharge shall expire at midnight on June 30, 2004.
Signed this day
A. Preston Howard, Jr., P.E., Director
Division of Water Quality
By Authority of the Environmental Management Commission
is hereby authorized
Permit No. NC0037834
SUPPLEMENT TO PERMIT COVER SHEET
City of Winston-Salem
i
1. Continue opera 'on of an existiug 30.0 MGD wastewater treatment system::4cons ist;ng of
mechanical screening and grit removal. primary clarification, high ' h1 'ug itti
J14441, aeration basins, final clarification, sodium hypochlorite and bisulfite feed for
disinfection and dechlorination, two centrifuges with screw conveyors. sludge digestion,
polymer and iron salt feed facilities, an odor control system, and instrumented flow
measurement located at the Archie Elledge Wastewater Treatment Plant on Griffith Road,
Southwest of Winston-Salem in Forsyth County: and
2. Discharge from said treatment works at the location specified on the attached map into Salem
Creek which is classified C waters in the Yadkin -Pee Dee River Basin.
•••••• • •
CU—. •
SCALF, 1:24000
Latitude: 36°01'04" 5ub-Basin: 03-07-04
Longitude: 80°18'54"
Ouad #: C17SE
Stream Class: C
ReceivinQ Stream: Salem Creek
Permitted Flow: 30.0 MGD
City of Winston-Salem
NC0037834
Archie Elleciqe Wastewater Treatment Plant
:1
A (1). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS - FINAL
Permit No. NC0037834
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge from outfall(s) serial number 001-
Wastewater Treatment Plant Effluent. Such discharges shall be limited and monitored by the Permittee as specified below:
EFFLUENT CHARACTERISTICS
DISCHARGE LIMITATIONS
MONITORING REQUIREMENTS
Monthly
Average
Weekly
Average
Daily
Maximum
Effluent Measurement
Frequency
Sample
Type
Sample
Location'
Flow (MGD)
30.0
Continuous
Recording
1 or E
BUD. 5-Day. 20°C (April 1 - October 31)`
21.0 mg/L
31.5 mg/L
Daily
Composite
I, E, U, D
ROD�5-Dc
' (November 1 - Marc 1)2
O ntg/I.
45.0 mg/I. /
`�
/
tc
U, n
Total Susp
nded Re ld e�
30.0 g�b,
45.0 mg/1/
Daily
Compos
to
I. EN.*
NI I� ay N (
Aril 1 -Otober 31)
1.2 ma/1,
Daily
Compos
to
E. U. D
NH as N (
avember 1 Ma ch 31)
.�
0,0 n� /I,
-..*,, ‹
Compos
le
1 , U, 1)
Dissol ed
xygen3
-- -�
Daily
Grab
E. U. D
Fecal Colif
rm (geomet/ic an)
200/10Q
400/1'
Daily
Grab
E, U. D
ml
...1
Total Resi
ual Chloride
\
/
Daily
Grab
E
Tem er
•e—µ
- c
�- ,J �•
'_�
,:��
�)
c
Daily
Grab
E, U. D _
Conductivity
-
Monthly
Grab
E, U, D
Total Phosphorus
Weekly
Composite
E
Total Nitrogen (NO2+NO;+TKN)
Weekly
Composite
E
PII4
Daily
Grab
E
Cadmium
2/Month
Composite
E
Cyanide i(
0.6Ftg/L
26.0,ug/I.
Weekly
Grab
E
Zinc
2/Month
Composite
E
Copper
2/Month
Composite
E
Chronic Toxicity/ b
Quarterly
Composite
E
NOTES:
2
3
SThe pH shall not be less than 6.0 standard units or greater than 9.0 standard units.
Ca.....___,J Toxicity (Ceriodaphnia) ChV @ 76%; January. April. July, and October; See condition A(2) of this permit.
THERE SHALL BE NO DISCHARGE OF FLOATING SOLIDS OR VISIBLE FOAM IN OTHER THAN TRACE AMOUNTS. ,
be.4-c%�a)'..� . (ewe 1 n: - Si... l ( LA- Zo it if . Z 1 .1..-/c a. s -,-2 -"" /i— -w T
.611 4.4. ' A"I 1 �n.L / G/1 ✓' C. del 1 r �- ..:/ /r / S -�. I r 1 (.i.. T ,' GC.e...c.K 7-� 4-C.v.'".
:PA-- • (A
t
Sample Locations: 1 — Influent. E — Effluen U — Upstream at_Meaclowbrook Lane. D — Downstream at US Highway 1 Upstream and downstream samples shall be grab samples
collected 3/Week during the months of June, July, August, and September and Weekly during the remainder of the year with the exception of BOD. NH3-N, and conductivity.
BOD and N1-13-N instream samples shall be collected weekly and conductivity samples monthly. Instream monitoring is provisionally waived in light of the permittee's participation
in the Yadkin -Pee Dee River Basin Association. Instream monitoring will be immediately reinstated should the permittee end its participation in the Association.
The monthly average effluent BON and total suspended residue concentrations shall not exceed 15% of their respective influent values (85% removal).
0.4 y�c
The daily average effluent dissolved oxygen concentration shall .a t wslie Tess than 6.5 mg/L.
L1 )
,)
Permit No. NC0037834
SUPPLEMENT TO EFFLUENT LIMITATIONS
AND MOIVITORINC: REQUIREMENTS.:— , 9
} 8
SPECIAL CONDITIONS
A (2 } CHRONIC TOXICITTY PERMIT LIMIT' (QUARTERLY) 30.01Vi
The rmittee s
�* Y
conduct chronic toxicity tests "i7sing test procedures outlined in the North Carol to Phase
o e Effluent -Toxicity Test l? t'ordure--fRevised-Novenhbet-f99&)-or subsequent versioii -'
The effluent concentration defined as the Instream Waste Concentration (IWC) shall be 76%. The chronic
value will be determined using the geometric mean of the highest concentration having no detectable
impairment of reproduction or survival and the lowest concentration that does have a detectable impairment of
reproduction or survival. The presence of 48 hour acute toxicity will be determined using Fisher's Exact Test
at 48 hours from test initiation. The definition of "detectable impairment." collection methods, exposure
regimes, and further statistical methods are described by the document referenced above.
The permit holder shall perform at a minimum, quarterly monitoring using these procedures to establish
compliance with the permit condition. The tests will be performed during the months of January, April, July,
and October. Effluent sampling for this testing shall be performed at the NPDES permitted final effluent
discharge below all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the months in which tests were performed, using the parameter code THP3B for
the Chronic Value and TGA3B for the 48 hour Acute Toxicity measure (Pass/Fail). Additionally. DWQ Form
AT-3 (original) is to be sent to the following address:
Attention: Environmental Sciences Branch
North Carolina Division of
Water Quality
4401 Reedy Creek Road
Raleigh. NC 27607
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association uith the toxicity tests. as well as all dose/response data. Total residual chlorine of
the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the waste
stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is required,
the permittee will complete the information located at the top of the aquatic toxicity (AT) test form indicating
the facility name, permit number, pipe number, county. and the month/year of the report with the notation of
"No Flow" in the comment area of the form. The report shall be submitted to the Environmental Sciences
Branch at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, then monthly
monitoring will begin immediately until such time that a valid test is submitted. Upon submission of a valid
test, this monthly test requirement will revert to quarterly in the months specified above.
Should any test data from this monitoring requirement or tests performed by the North Carolina Division of
Water Quality indicate potential impacts to the receiving stream, this permit may be re -opened and modified to
include alternate monitoring requirements or limits.
Permit No. NC0037834
SUPPLEMENT TO EFFLUENT LIMITATIONS
AN) MONITORING 9QUIREMEN
SPECIAL C $ND TIONS
re to aclrie'e=test• conditioizo a op rcified in -this-cited-dacuinelit, such as miiii i uur-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.
DENR/DWQ
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES No. NC0037834
Facility Information
Applicant/Facility Name:
City of Winston-Salem — Archie Elledge WWTP
Applicant Address:
P.O. Box 2511, Winston-Salem, NC 27102
Facility Address:
On Griffith Road, Winston-Salem. NC
Permitted Flow
30.0 MGD
Type of Waste:
22% industrial
78% domestic
Facility/Permit Status:
Renewal w/o expansion
County:
Forsyt h
Miscellaneous
Receiving Stream:
Salem Creek - 001
Regional Office:
Winston-Salem
Stream Classification:
C
USGS Topo Quad:
CI7SE
303(d) Listed?:
YES
Permit Writer:
Mark McIntire
Subbasin:
03-07-04
Date:
March 5, 1999
Drainage Area (mi2):
67.3
Summer 7Q10 (cis)
15
Winter 7Q10 (cfs):
18
Average Flow (cfs):
65
IWC (%) @ 30.0 MGD:
76%
Primary SIC Code:
4952
Treatment Plant Class:
IV
SUMMARY
This facility is a major municipal treatment plant operating in Forsyth County. At 30.0 MGD, it is one of the
largest municipal facilities in the state. Originally permitted in the late 70s, this facility has undergone no
expansions. Multiple Authorizations to Construct have been issued since for this facility and are summarized
below:
ATC Issuance Date
Description
August 1, 1978
Construction of 30.0 MGD additions including an intermediate lift station. flow
splitter box, dual nitrification basins, four final clarifiers, two return sludge pump
stations, an effluent pump station, two caustic storage tanks, waste sludge
collection facilities, a waste sludge thickener, a flood discharge lift station, flow
measurement, chlorination. and post aeration.
September 3, 1980
Construction of regional laboratory and maintenance building.
May 11, 1992
Installation of a mechanical bar screen, a screenings conveyor. grit collectors and
conveyors, pump station modifications. aeration basin pumps, blowers and
aeration equipment, chlorination equipment, dechlorination equipment, flow
measurement, odor control facilities, chemical feed equipment. a polymer feed
system, gravity belt thickeners, digester mixers. digester roof modifications. and
sludge metering facilities.
March 29, 1993
Construction of an additional chlorine contact tank.
February 27, 1998
Installation of sodium hypochlorite and sodium bisulfite storage and feed facilities,
removal of existing chlorine gas and sulfur dioxide gas storage and feed facilities,
installation of temporary disinfection and dechlorination facilities and four new
final clarifier mechanisms.
June 19, 1998
Construction of a one-story reinforced concrete building with masonry walls and
below grade pump and conveyor room, a control room, electrical room. lavatory.
WS — Archie Elledge Fact Sheet
NPDES Renewal
Page 1
i
two centrifuges with conveyors, digested sludge pumps, centrate wetwell and
pumps, polymer and iron salt feed, odor control scrubbing system, bridge crane.
SCADA system, and sludge dewater receiving pit
As indicated above, this facility discharges into Salem Creek which is a listed stream on North Carolina's 303(d)
list. The creek is listed as partially supporting its designated uses as the result of non -point sources of fecal
coliform, turbidity, and sediment. Although this discharge dominates the receiving stream, oxygen consuming
wastes do not appear to be a problem. Prior to 1995, the facility was required to meet fecal coliform limitations
of 1000/100 ml and 2000/100 ml monthly average and weekly average respectively. Beginning in 1995, these
limits dropped to 200/100 ml and 400/100 mi. Prior to 1995, effluent fecal coliform levels were consistently
in the thousands of colonies per 100 ml. Now, effluent levels are consistently below 10, indicating a major
improvement to the facility's disinfection strategy.
The current permit was issued on September 30, 1994, and adjudicated with the Office of Administrative
Hearings on October 31, 1994. The permit petition questioned the installation of cyanide limits as well as the
aforementioned more stringent fecal coliform limitations. In accordance with the mediated settlement held on
March 10, 1995, the permit was reissued in May of that year with a delayed implementation schedule for the new
fecal coliform limits and a requirement to complete a cyanide study for the purposes of establishing a site -specific
cyanide quantitation level.
The required cyanide study was completed in accordance with the reissued permit and was subsequently reviewed
by staff from the Division. The study concluded that a 20 ppb cyanide quantitation level was appropriate for the
wastewater matrix present. It indicated that numerous false positive results were reported using quantitation
levels lower than 20. The Division accepted the report's recommendations. As a result of this site specific study.
the quantitation level will remain unchanged at 20 ppb instead of the currently accepted value of 10 ppb.
The permit application specifically requested deletion of color monitoring at the effluent. Color monitoring has
been deleted as Division policy does not mandate monitoring. Monitoring will be reinstated should the Division
develop and plan of study.
A reasonable potential analysis was completed for cadmium, providing justification for the elimination of
cadmium limitations. No analysis was completed for cyanide, zinc, or copper. Cyanide was reported at levels
higher than the allowable concentration, therefore reasonable potential exists for a standard violation. Zinc and
copper both have action levels. These parameters are only limited where they are shown to be causative factors
to whole effluent toxicity. As summarized below, this facility has had no problems with toxicity testing.
LTMP REVIEW
The facility's LTMP data is being reported on its DMRs. This data was reviewed during the compliance review.
TOXICITY TESTING:
Type of Toxicity Test:
Existing Limit:
Recommended Limit:
Monitoring Schedule:
Chronic Phase II
001: Chronic ChV @ 76%
001: Chronic ChV @ 76%
January. April, July, and October
The facility failed a single toxicity test in 1995 and has passed all tests since.
COMPLIANCE SUMMARY:
This facility operates well, remaining in compliance with permit limitations.
INSTREAM MONITORING:
Instream monitoring is currently required for BOD, ammonia, DO, fecal coliform, temperature, conductivity and
color. All instream monitoring requirements have been provisionally waived due to the facility's participation in
WS — Archie Elledge Fact Sheet
NPDES Renewal
Page 2
the Yadkin -Pee Dee River Basin Association (the Association). During the i.. _pious renewal period, instream
monitoring for BOD, TSS, and NH;-N was changed to weekly year-round, while conductivity monitoring was
changed to monthly year-round. These monitoring frequencies will be maintained and implemented in the event
that the facility ceases participation in the Association.
PROPOSED CHANGES:
• Cadmium Limitation: A reasonable potential analysis has indicated that there is no need to maintain the
cadmium effluent limitation. As such, the limitation has bee deleted and monitoring has been decreased from
weekly to 2/month.
• Effluent Pages: Summer and winter requirements have been incorporated onto a single effluent page.
• Instream Monitoring: Due to Winston Salem's participation in the Yadkin -Pee Dee River Basin Association
(the Association), instream monitoring requirements have been provisionally waived and stated as such on the
effluent limitations page.
• Color Monitoring: Color monitoring has been eliminated from the permit.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice: May 5, 1999
Permit Scheduled to Issue: June 21, 1999
STATE CONTACT:
If you have any questions on any of the above information or on the attached permit. please contact Mark
McIntire at (919) 733-5058 ext. 553.
NPDES UNIT COMMENT:
NAME:
,2,i ( DATE: 9
REGIONAL OFFICE COMMENT:
\Lv.,r5
NAME: DATE:
EPA COMMENT:
WS — Archie Elledge Fact Sheet
NPDES Renewal
Page 3
PRE-TREATMENT
BASINS
SAND DRYING BEDS
LINED LANDFILL
21.4 MGD
INFLUENT
Schematic of
Process Flow
Archie Eliedge
WWTP
NPDES No.
NC0037834
Winston-Salem
NorthCarolina
December 23,1997
SCREENS AND
GRIT REMOVAL
C
NAEROBIC
DIGESTERS
1
284 TGD
PRIMARY SLUDGE 211 TGD
TWAS 103.8 TGD
LAND APPLICATION
GRAVITY
BELT
THICKENER
SLUDGE
HOLDING
TANK
CHLORINE CONTACT
& POST AERATION
DECHLORINATION
EFFLUENT TO SALEM CREEK
LEGEND
PRIMARY
CLARIFIERS
ACTIVATED
SLUDGE
BASINS
WAS 693 TGD
RAS 25.6 MGD
WASTEWATER FLOW
SOLIDS FLOW
Facility Name =
Winston-Salem
Parameter =
Cadmium
NPDES # =
NC0037834
Standard =
2
pg/I
Qw (MGD) =
30
7Q1Os (cfs)=
15
n
BDL=1/2DL
_
Actual Data
RESULTS
ZINC (%) =
75.61
1
0.65
<1.3
Std Dev.
0.150302
2
0.65
<1.3
Mean
0.6934211
FINAL RESULTS
3
0.65
<1.3
C.V.
0.2167543
Cadmium
4
0.65
<1.3
Max. Pred Cw
1.44
5
0.65
<1.3
Allowable Cw
2.6
6
1.2
1.2
Mult Factor
1.2
7
1.2
1.2
Max. Value
1.2
ro (.6._;4-
8
1.2
1.2
Max. Pred
, 1.44
9
0.65
<1.3
Allowable
2.6
10
0.65
<1.3
11
0.65
<1.3
12
0.65
<1.3
13
0.65
<1.3
14
0.65
<1.3
15
0.65
<1.3
16
0.65
<1.3
17
0.65
<1.3
18
0.65
<1.3
19
0.65
<1.3
20
0.65
<1.3
21
0.65
<1.3
22
0.65
<1.3
23
0.65
<1.3
24
0.65
<1.3
25
0.65
<1.3
26
0.65
<1.3
27
0.65
<1.3
28
0.65
<1.3
29
0.65
<1.3
30
0.65
<1.3
31
0.65
<1.3
32
0.65
<1.3
33
0.65
<1.3
34
0.65
<1.3
State bf North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
Stanley B. Webb
City of Winston-Salem
PO Box 2511
Winston-Salem, NC 27102
Dear Permittee:
NC DENR
September 21, 1998
Subject: Modification of NPDES Permit No. NC0037834
Elledge WWTP
Forsyth County
The Division is beginning the second five-year cycle of river basin planning and permit renewals. An
examination of the basin planning schedule has revealed that the timing of permit renewals does not
allow an evenly distributed workload as first envisioned. This results in problems with the efficiency
and effectiveness of the NPDES program. In an effort improve customer service, and after thorough
review of the water quality issues in your area, the Division is changing the permit renewal schedule for
all NPDES permits in your sub -basin.
This permit modification changes the expiration date of the subject permit to June 30, 1999. Please
find enclosed the revised permit cover page. Insert the new cover page into your permit and discard the
old page. All other terms and conditions contained in the original permit remain unchanged and in full
effect. This permit modification is issued pursuant to the requirements of North Carolina General
Statutes 143-215.1 and the Memorandum of Agreement between North Carolina and the U. S.
Environmental Protection Agency.
If you have already submitted a permit renewal application for the subject facility, the Division will
retain the application until your permit is due for renewal. No additional forms or fees will be required.
If any parts, measurement frequencies or sampling requirements contained in this permit modification
are unacceptable to you, you have the right to an adjudicatory hearing upon written request within
thirty (30) days following receipt of this letter. This request must be a written petition conforming to
Chapter 150B of the North Carolina General Statutes, filed with the Office of Administrative Hearings,
Post Office Drawer 27447, Raleigh, North Carolina 27611-7447. Unless such demand is made, this
decision shall be final and binding.
If you have questions about this modification, please contact Charles Weaver of my staff at the
telephone number or address listed below.
Sincerely,
Preston Howard, J'f , P.E.
cc: Central Files
Winston-Salem Regional Office, Water Quality Section
Roosevelt Childress, EPA
NPDES Unit Files
Point Source Compliance Enforcement Unit
P.O. Box 29535, Raleigh, North Carolina 27626-0535 919 733-5083, extension 511 (fax) 919 733-0719
An Equal Opportunity Affirmative Action Employer Charles_Weaver@h2o.enr.state.nc.us
Permit No. NC0037834
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 provision of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended,
City of Winston-Salem
is hereby authorized to discharge treated wastewater from a facility located at
Elledge WWTP
Winston-Salem
Forsyth County
to receiving waters designated as subbasin 30704 in the Yadkin -Pee Dee River basin.
in accordance with the effluent limitations, monitoring requirements, and other conditions set forth
in Parts I, II, III and IV hereof.
This permit shall become effective September 21, 1998.
The permit and authorization to discharge shall expire on June 30, 1999.
Signed this day September 21, 1998.
. Preston Howard, Jr., P.E., Director
Division of Environmental Management
By Authority of the Environmental Management Commission
NORTH CAROLINA
DAVIDSON COUNTY
Notice of Intent
o Extend The Duration of NPDES Discharge Permits in the Yadkin River basin
:OBJECT: The Division or Water Quality plans to extend the duration of existing
1PDES Permits for the following facilities:
Irmrit Facility
4C0070637 Piedmont Converting, Inc.
4C0083941 Heater Utilities -Twin Creeks
4C0070033 Quail Run Mobile Home Park
4C0040045 Bills Truck Stop. Inc.
4C0004626 PPG Industries - Lexington
400059218 Captain Steven's Seafood Restaurant
4C0084425 Davidson Water, Inc. - WTP
4C0023604 Thomasville Furniture - SFD Plant
4C005936 Hilltop Living Center
4C0041599 Davidson Co. Schools -Central Middle/Senior High
4C0029947 Davidson Co. Schools-Churchland Elementary
4C0042072 Davidson Co. Schools -Northwest Elementary
4C0042072 Davidson Co. Schools -Silver Valley Elementary
4C0044249 Davidson Co. Schools -Southwood Elementary
4C0042056 Davidson Co. Schools -Tyro Jr. High
4C0031950 Davidson Co. Schools -West Davidson H.S.
4C0061204 Scarlelt Acres Mobile Home Division
4C0046931 Norfolk Southern Railway Company
4C0057223 Head Mobile Home Park
4C0051489 Three R's Mobile Home Park
4C0057509 Carolina Water Service -Sequoia
4C0065587 Mid -South Water Systems/Frye Bridge
4C0085871 ABB Flakt,lncJFlakt Products
4C0080853 Lucent Technologies, Inc./Salem Business Park
4C0004707 RJ Reynolds - Downtown
4C0055093 RJ Reynolds - Tobaccoville
4C0086011 City of Winston-Salem / Neilson WTP
4C0079821 City of Winston-Salem / Thomas WTP
4C0037834 City of Winston-Salem / Elledge WTP
4C0050342 City of Winston-Salem / Muddy Creek WTP
4C0083739 Crown Central Petroleum Corporation
4C0067385 BP Service Station - Site #24".
4C0084115 Wachovla Southern Oil Co.
4C0084760 Usair Smith -Reynolds Maintenan
4C0085138 Loves Foods-S. Main St; #826
4C0037184 Oak Haven Mobile Home Park
4C0061034 Rowan Associates & Mercantile Center
4C0042439 Westside Swim & Racquet Club
4C0045675 Majestic Properties - Rowan Site
4C0025593 Town of Spencer - WWTP
4C0027502 Town of Landis - WTP
4C0035921 Rowan -Salisbury Schools/Faith Elementary
4C0034703 Rowan -Salisbury Schools/ Knollwood Elementary
4C0049905 Inman Asphalt. Inc. - Salisbury
4C005487 Color -Tex Finishing Corporation
4C0004774 Duke Power - Buck Steam Station
400023884 City of Salisbury - Grant Creek WWTP
4C0023892 City of Salisbury - Town Creek WWTP
County
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON•
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
DAVIDSON
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
FORSYTH
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
ROWAN
'impose: The facilities listed above all discharge into the Yadkin River basin. Other
termiis in the Yadkin River basin have expiration dates in calendar year 1999. The
acilities listed above have permit expiration dates in 1998. In order for the Division to
.valuate all permit renewal requests in the Yadkin River basin during the same calendar
ear, the Division plans to extend the expiration dates of the permits for the facilities
istcd above. No conditions in the existing permits will be changed or modified. This is
in administrative change to better align permitting and Basinwide Planning operations
vithin the Division of Water Quality. On the basis of preliminary staff review of Article
!I Chapter 143, General Statutes of North Carolina (and other lawful standards and
egulations), the North Carolina Environmental Management Commission proposes to
:xtend the duration of the NPDES permits listed above. subject to specific pollutant
tmitatiens and special conditions.
NFORMATION: A copy of the existing NPDES permits and a sketch showing the
ocation of each discharge is available by writing or calling:
Mr. Charles Weaver
NC DENE - DWQ - NPDES Unit
P.O. Box 29535
Raleigh. North Carolina 27626-0535
Telephone Number. (919) 733-5083. ext. 511
The existing permits are on file at the Division of Water Quality, Archdale Building, 512
North Salisbury Street (Room 925), Raleigh, North Carolina. They may be inspected
luring normal office hours. Copies of the information on file are available upon request
and payment of the costs of reproduction.
Date: July 27, 1998 ! f,•^r !r.�!-_-
For A. Preston Howard, ir., P.E., Director
Division of Water Quality
AFFIDAVIT OF PUBLICATION
Before the undersigned, a Notary Public of said
County and State, duly commissioned, qualified, and
authorized by w to ad aster oaths, personally
appeared Nifr.,.... e.A.Pn.l7;1-er , who
being first,dulysworn deposQ@s and says: that he is
4d� e$3 zSf1('t....ci.L S,t1�L of The
Thomasville Timid, Inc., engaged In the publication of
a newspaper known as The Thomasville limes,
published, Issued, and entered as second class mail in
the City of Thomasville in said County and State; that
he (she) is authorized to make this affidavit and swom
statement; that the notice or other legal advertisement,
a true copy of which is attached hereto, was published
in The Thomasville Times on the following dates:
• and that the
said newspaper in which such notice, paper,
document, or legal advertisement was published was,
at the time of each and every such publication, a
newspaper meeting all 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 General
Statutes of North Carolina.
•
This ./ day of :,:4r. 11 , 19.9E..
Sworn to and subscribed be Aqr, me, this
day of.....�.._lVI ..., 19...Y.X.
My Commission Expires
Notary Public
1998
State of North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
July 27, 1998
Stanley B. Webb
City of Winston-Salem
P 0 Box 2511
Winston-Salem, NC 27102
A 17
NC DENR
Subject: Status of NPDES Permit NC0037834
Forsyth County
Dear Permittee:
After a thorough review of the Yadkin -Pee Dee River basin management plan and water quality issues relevant to
the subject facility, the Division of Water Quality has decided to extend the duration of the subject permit. The
expiration date of your permit will be changed in order to allow the Division to review all NPDES discharge
permits in the Yadkin River Basin during calendar year 1999.
All terms and conditions in the existing permit will apply until a new expiration date is assigned by the Division.
Extension of existing Effluent Limitations and Monitoring Requirements does not exempt the subject facility from
the new Enforcement Policy recently enacted by the Division.
Attached to this letter is a copy of the Public Notice that is being published to announce the planned extension of
your permit. After Public Notice has been made by the Division, the expiration date of your permit will be
changed via a permit modification. No draft permit will be sent out with the Public Notice, as none of the
conditions in the existing permit will be modified.
The Division appreciates your patience and understanding to date regarding the rescheduling of the subject
permit. If you have already submitted your renewal application package, no additional fees or documentation will
be required as a result of this change to your permit's expiration date.
If you have questions about this proposed modification or about the permit renewal process, contact Charles
Weaver of my staff at the telephone number or address listed below.
Sincerely,
A. Preston Howard, r., P.E.
cc: Central Files
Winston-Salem Regional Office, Water Quality Section
NPDES File
P.O. Box 29535, Raleigh, North Carolina 27626-0535 919 733-5083, extension 511 (fax) 919 733-0719
An Equal Opportunity Affirmative Action Employer Charles_Weaver@h2o.enr.state.nc.us
State of .North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
James B. Hunt, Jr., Governor
Wayne McDevitt, Secretary
A. Preston Howard, Jr., P.E., Director
Barry Shearin
City of Winston-Salem / Elledge WWTP
P.O. Box 2511
Winston-Salem, NC 27102
Dear Permittee:
All7A
NC DENR
June 1, 1998
Subject: Implementation of Yadkin Pee -Dee River Basin Association
NPDES Permit Modification for Instream Sampling
NPDES Permit NC0037834
Forsyth County
As a participant in the coordinated instream monitoring efforts within the Yadkin -Pee Dee River basin,
your facility and the North Carolina Department of Environment and Natural Resources (DENR) have
entered into an agreement that provides both parties with an effective environmental monitoring tool. By
this letter, the DENR is waiving the instream monitoring requirements as specified within your individual
NPDES permit beginning June 1, 1998. As specified in the Memorandum of Agreement (MOA) signed by
this agency and you (or your representative), the agreement identifies the stations, parametric coverage
and frequency of analysis required in order that the instream monitoring requirements be waived for your
facility.
All other terms and conditions in the original permit remain unchanged and in full effect. These
modifications are 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 December 6, 1983. Should your membership in the agreement be terminated, the instream
monitoring requirements specified in your permit will be reinstated. You shall notify the Division
immediately upon termination of membership.
I would like to express my appreciation for the cooperation and participation of all participants in this
innovative approach to environmental monitoring. It is expected that the results of the agreement will
effectively contribute to our understanding of the Yadkin -Pee Dee River basin environment. We have
designated Cathy Tyndall as our primary contact for issues related to the MOA. She can be reached at
(919) 733-6510.
We also look forward to the advances that this cooperative agreement will provide in our management of
the Yadkin -Pee Dee River basin and ask that you feel free to contact us should any questions arise
regarding the monitoring efforts or interpretations of the information collected. We will be maintaining
our own series of monitoring stations in the basin which, when added to the information collected by this
agreement, will greatly expand our knowledge of this environmental system. We thank you again for your
participation and look forward to a successful monitoring effort.
Sincerely,
Preston Howard, Jr., P.E.
cc: Central Files
Winston-Salem Regional Office, Water Quality Section
Susan Wilson, Point Source Compliance Enforcement Unit
Cathy Tyndall, Environmental Sciences Branch
NPDES Unit Files
P.O. Box 29535, Raleigh, North Carolina 27626-0535 919 733-5083, extension 511 (fax) 919 733-0719
An Equal Opportunity Affirmative Action Employer 50% recycled / 10% post -consumer paper
February 11, 1998
Mr. Stanley B. Webb
Wastewater Operations Superintendent
City of Winston-Salem
P.O. Box 2511
Winston-Salem, NC 27102
Subject: Archie Elledge WWTP (NC0037834)
Muddy Creek WWTP (NC0050342)
Permit Information Request
City of Winston-Salem/Forsyth Co.
Dear Mr. Webb:
In response to your letter dated December 10, 1997 please note the following information
about the Division's Yadkin River Basinwide Management Plan, as well as speculative limits for
the Archie Elledge WWTP coupled with a reduced effluent dissolved oxygen (DO) limit:
• During the next five year permitting cycle for the Yadkin River Basin the Division does not
anticipate any permit limit changes for either the Archie Elledge (30 MGD) or Muddy Creek
(21 MGD) WWTPs at current permitted flow. However, the City should expect stricter limits
for oxygen consuming wastes in the Archie Elledge NPDES permit if this facility plans any
expansion of its wasteflow above its current 30 MGD limit, or if water quality standards in
Salem or Muddy Creeks are not being met. Currently, the instream standard for DO is being
protected, however the Division is concerned about the relatively low DO concentrations (mid
5 to 6 mg/L range) which were reported during a low stream flow period in 1995. During this
period the Elledge WWTP was treating to well below its BODS limit, which suggests that the
assimilative capacity of Muddy and Salem Creeks may be over allocated.
Additional field data may need to be collected before an assessment could be made regarding
speculative permit limits for the Muddy Creek WWTP in association with an expanded
wasteflow from this facility. Additional information concerning oxygen consuming wastes
and related management strategies for Salem and Muddy Creeks can be found on pages 6-14
and 6-15 of the enclosed DRAFT Yadkin Basinwide Management Plan.
As you may already be aware, the Division is investigating the possibility of designating all or
a portion of the High Rock Lake watershed as Nutrient Sensitive Waters (NSW). Both of the
City's major WWTPs would likely be affected by a reclassification to NSW of the respective
receiving streams. Again, during the next 5 years no changes to NPDES permits are
expected. However, the Division does recommend that major dischargers in the High Rock
Lake watershed, which includes the City of Winston-Salem, act to improve phosphorous
removal. Additional information on this topic can be found beginning on page 6-9 of the draft
management plan.
• In your letter you requested speculative limits for BODS and ammonia coupled with a
reduced DO effluent concentration. With a DO limit of 6.0 mg/L and 5.5 mg/L the following
limits would apply for oxygen consuming wastes at the Elledge WWTP:
Wasteflow (MGD)
BOD5 (mg/L)
NH3-N (mg/L)
DO (mg/L)
Wasteflow (MGD)
BOD5 (mg/L)
NH3-N (mg/L)
DO (mg/L)
Archie Elledge WWTP
Summer Winter
30 30
16.0 30.0
1.2 4.0
6.0 6.0
Summer Winter
30 30
12.0 24.0
1.2 4.0
5.5 5.5
A complete review of other permit limits including toxicants/metals will be conducted after receipt of a permit
application or modification.
If you have any questions please contact Andy McDaniel, 919-733-5083 ext 513.
Sincerely,
David Goodrich
NPDES Unit Supervisor
Cc: Mike Mickey (Winston-Salem Regional Office)
Permits and Engineering Unit
Modeling/TMDL Unit
Attachment: Draft Yadkin Basinwide Management Plan
CITY OF VINSTON-SALEI
PUBLIC WORKS DEPARTMENT
P.O. BOX 2511, WINSTON-SALE\1. NORTH CAROLINA 27102
January 20, 1998
Mr. Don Safrit
North Carolina Department of Environment,
Health and Natural Resources
Division of Water Quality
P.O. Box 29535
512 North Salisbury Street
Raleigh, North Carolina 27626-0535
Re: NPDES Permit Renewal Application
Archie Elledge WWTP (NC0037834)
Winston-Salem; Forsyth County
Dear Mr. Safrit:
Three sets of the documents necessary to renew the NPDES Permit for Winston-Salem's Archie
Elledge WWTP are attached. A check in the amount of $800 is also included to cover the permit
renewal fee for both the Muddy Creek and Archie Elledge WWTPs. The discharge permits for
these plants expire on July 31, 1998.
Please note that Winston-Salem is also submitting an application to renew the federal sludge
disposal permits for these facilities to EPA. Although Region IV of EPA has never issued
Winston-Salem a sludge disposal permit, we are required to reapply for a 503 permit when we
renew our NPDES permits.
Winston-Salem has several concerns regarding existing and anticipated limitations. We would
appreciate DWQ considering the comments provided below while preparing the draft document:
Cyanide Monitoring:
The plant's existing permit was amended on October 31, 1996 to include a stipulation recognizing
a detection limit of 20 ppb for cyanide. DWQ implemented this amendment following their
review of a cyanide study conducted at the Elledge Plant by CH2M Hill.
Winston-Salem asks that the new permit incorporate the existing cyanide language shown on the
"Effluent Limitations and Monitoring Requirements" page of the permit currently in effect.
Mr. Don Safrit
January 20, 1998
Page 2
Color Monitoring:
The plant's existing permit requires color monitoring twice per month at the upstream, effluent
and first downstream sampling sites.
This monitoring requirement was incorporated into the existing permit to establish a data base for
color. Winston-Salem feels that we have provided DWQ enough monitoring data for this
parameter and we ask that the color monitoring requirement be deleted from the new permit.
Dissolved Oxygen:
The Elledge Plant's current effluent dissolved oxygen limit is 6.5 mg/1. Winston-Salem will be
requesting a more stringent dissolved oxygen limit after we review the information provided us in
response to my letter to Dave Goodrich of December 10, 1997. We have asked DWQ to evaluate
the effect a reduction in D.O. to 6.0 and 5.5 mg/1 would have on the BOD and Ammonia limits.
Thank you for your consideration in this matter and please call me at 336-784-4700 if you have
any questions or need additional information.
cd&P
Stanley B. Webb
Wastewater Operations Manager
PC: David Saunders; Utility Plants Engineer
Mike Mickey; DEHNR Regional Office
Ref: let0112.98b
BIOSOLIDS DISPOSAL STRATEGY
CITY OF WINSTON-SALEM
ARCHIE ELLEDGE WWTP
MUDDY CREEK WWTP
Residual biosolids from both of Winston-Salem's two wastewater treatment plants are treated to
meet the Class B criteria established by the EPA's 503 Sludge Disposal Regulations. This level of
treatment is achieved by subjecting the biosolids to anaerobic digestion at 94 degrees Fahrenheit
for at least 45 days. The average digestion time at the Elledge Plant is —48 days and the Muddy
Creek Plant's digestion time is —67 days. Both facilities meet or exceed the volatile solids
reduction criteria established by USEPA for vector control.
Winston-Salem's primary sludge disposal strategy is to land apply its digested biosolids to farm
land at an agronomic rate. Winston-Salem currently has 8,622.08 acres of agricultural land
permitted to receive biosolids. These lands lie in Davie and Yadkin counties and solids are
applied to these sites in accordance with the requirements of DWQ non discharge permit
WQ0000094.
Winston-Salem has also applied to Region IV of EPA for a federal sludge disposal permit. We
submitted this application to EPA in February of 1994 but the permit has not yet been issued.
Archie Elledge WWTP
The Archie Elledge WWTP currently produces —24 dry tons of digested biosolids daily. Under
normal conditions, these solids are stored in one of three sludge holding lagoons until they are
land applied. These three lagoons have a combined storage capacity of 32.4 million gallons.
While in the lagoons free water forms as the solids settle to the bottom. This free water is
removed and this process serves to thicken the solids content of the biosolids from —2% to —5%.
The solids concentration in the biosolids actually land applied varies according to the crop being
grown, but on average this value is 5.47%.
Adverse weather and cropping patterns prevent our being able to land apply biosolids on a
continual basis. During these times, solids are stored in the holding lagoons until we are able to
resume land application.
If conditions are such that we anticipate exhausting all our storage space before we can resume
application operations, we utilize contract dewatering firms to dewater the plant's daily sludge
production. The plant may also utilize its sixteen acres of sand drying beds in conjunction with
mobile dewatering equipment to dewater its sludge production. All biosolids dewatered under
these conditions are disposed of in a lined solid waste landfill.
Biosolids Disposal Strategy
Winston-Salem, N.C.
Page 2
Muddy Creek WWTP
The Muddy Creek WWTP produces —8 dry tons of biosolids daily. The plant has mechanical
dewatering facilities which dewater —37% of the daily biosolids production. The remaining solids
are stored the plant's 12.8 million gallon lagoon storage system until they are land applied. The
plant's lagoons are not large enough to contain the daily sludge production during periods when
land application is not possible, so belt filter presses are operated continually to supplement the
lagoon's storage capacity.
The Muddy Creek Plant is equipped with a sludge blending facility which is designed to mix
dewatered cake with the thinner biosolids removed from the holding lagoons. This operation
allows the plant to formulate a biosolids slurry with a nutrient content that is appropriate for the
crop being grown on the application site.
In the event the plant exhausts all its lagoon and cake storage capacity during periods when field
operations cannot be conducted, the plant's strategy is to dewater its entire daily solids
production and dispose of the resulting cake in a lined landfill.
Future Disposal Strategy
Winston-Salem has retained Black and Veatch Engineers to evaluate its residual management
program and recommend an appropriate long term strategy.
This evaluation concluded that Winston-Salem's total biosolids production will ultimately increase
from the current 32 dtpd to —52 dtpd. Given this, it is expected that the rate of development in
our service area may result in an inadequate supply of suitable farmland to support land
application as our sole disposal option.
Black and Veatch has recommended that Winston-Salem begin building permanent dewatering
facilities for the Eliedge Plant as a first phase of a long term residuals management strategy.
These facilities are currently in design and we expect to begin construction in early summer of
1998. The engineer estimates that this equipment will be on line by the fall of 1999.
The second phase of the management strategy recommended by Black and Veatch will be to begin
piloting work to identify a Class A disposal option to augment our land application program. Our
long term strategy is to continue land applying all the residual biosolids that we can and utilize the
most cost effective Class A option to dispose of the excess.
We will continue disposing of sludge cake in a lined landfill until the facilities are on line to
implement a suitable Class A disposal option.
ALTERNATIVES TO DISCHARGE ANALYSIS
ARCHIE ELLEDGE WWTP
MUDDY CREEK WWTP
CITY OF WINSTON-SALEM, NORTH CAROLINA
Upon the completion of the upgrade currently in progress at Winston-Salem's Muddy Creek
WWTP, the combined permitted flow for these facilities will be 51 MGD. Winston-Salem is not
requesting an increase in permitted flow capacity for either of these plants at this time. Facilities
are either currently in place or under construction to adequately treat the permitted flow at each
of the plants.
The size and location of these plants are such that it is difficult to identify and implement
alternatives to continuing point source discharges to a receiving stream. Several alternatives to
surface water discharge were evaluated as part of this permit renewal application and the results
of these evaluations are itemized below.
Diverting Discharges to a Regional Treatment Facility:
This alternative is not a viable option because there are no other treatment facilities in the area
with the capacity to assimilate the flow and organic loading currently being treated by the Archie
Elledge and Muddy Creek WWTPs.
This option is also not considered a means by which a discharge of treated wastewater to a stream
is actually prevented since the wastewater treated by the "Regional Facility" would only be
discharged into a different stream.
Land Applving the Treated Wastewater to Agricultural Land:
This alternative would involve pumping the combined effluents from the two plant to a site where
treated wastewater would be applied at rates of-5 feet/acre/year to agricultural crops or a tree
farm. This alternative would involve the purchase of a large tract of land and the construction of
pumping and distribution facilities needed to get the plant's effluent to the application site and
apply it. The construction of a lagoon to provide —20 days storage capacity during freezing
weather and precipitation events would also be constructed.
The criteria used to evaluate this alternative are as follows:
- Type of System
- Design Flow
- Avg. Annual Precipitation
- Soil Percolation Rate
- Design Hydraulic Loading Rate
- Estimated portion of Discharge
Site unavailable for use
Slow Rate Application
51 MGD
42.6 inches
0.6 to 2 inches per hour
5 feet/acre/year (1.63 MG/acre/vear)
15%
Alternatives to Discharge Analysis
City of Winston-Salem, North Carolina
Page 2
-Total area Required Annually for 13,400 acres
- Inclement Weather Storage --- 20 days (1 billion gallons)
A "Slow Rate" System was chosen for this evaluation because this system is less likely to cause
nitrate contamination in the underlying ground water. A low rate of application will also reduce
the possibility of"run-off" from the site into adjacent lands or waterways. The operation of this
system would have to be conducted at low hydraulic loading rates due to the low percolation
rates of the clay loam soils prevalent in the upland regions of the piedmont area.
The estimated cost to purchase the land and construct the facilities that would be needed to
implement this alternative are shown below:
***Land Discharge Facility Cost Estimates***
* Effluent Pumping Station and Forced Main $7,100,000
* Cost of Land (Disposal Site and Storage Lagoon) $108,427,000
13,554 acres @ $8000
* Cost to Construct Storage Lagoon $99,030,000
4,951,475 yards @ $20
* Cost for Distribution System on Application Site $2,000,000
Subtotal $216,557,000
* Engineering and Contingency at 20% $43,311,000
Grand Total: $259,868,400
This option is to expensive to be a practical alternative to a surface water discharge.
Furthermore, the region in and around Winston-Salem are highly developed and there are no large
tracts of land available for use as a land disposal site.
Winston-Salem is also concerned that the implementation of this alternative may result in the
removal of enough water from the Yadkin River Basin to cause water supply problems in the
lower reaches of the river during 7Q10 flow events. Currently, the permitted flow capacity of
Winston-Salem's wastewater treatment plants amounts to 14% of the rivers 7Q10 flow.
Alternatives to Discharge Analysis
City of Winston-Salem, North Carolina
Page 3
Reduction in Discharge Flow
The size and location of the Muddy Creek and Archie Elledge Wastewater Treatment Plants are
such that practical alternatives to continued discharge to surface waters do not exist. Winston-
Salem feels that it is necessary for us to continue discharging to a receiving stream but we have
adopted a strategy to minimize the rate of increase in our discharge flows by constantly surveying
our collections system to control routes of inflow and infiltration.
During the past two years we have concentrated these efforts in the collection lines we
incorporated into our system from the Town of Kernersville and Rural Hall. Our best estimate is
that we have reduced inflow and infiltration in these systems by —40%.
We have also established rainfall monitoring equipment in key drainage areas so we can correlate
increases in pumping rates at lift stations with rainfall events. This allows us to determine the time
lag between rainfall events and peak flow periods so we can locate likely areas where an I&I
problem may be occurring.
We are also reviewing proposals from various Engineering Firms to conduct a detailed study of
our system to identify ways to reduce uncontaminated flow into our POTWs.
Ref:alteff 98
CITY OF \VINSTON-SALEM
PUBLIC'. \VORKS I)I?PAR'I'MIE,N'I'
I'.(). I%()N 2511. WINSION-SAl.EM1, N()RTII (:AR()I.INA 27102
December 10, 1997
Mr. Mark McIntire
North Carolina Department of Environment,
Health and Natural Resources
Division of Water Quality
P.O. Box 29535
512 North Salisbury Street
Raleigh, North Carolina 27626-0535
Subject: NPDES Permit Renewal Application
Authorization to Delete Section IV of Standard Form A
City of Winston-Salem/Forsyth County
Dear Mr. Mclntire:
Per our telephone conversation of December 10, 1997. Winston-Salem will not be required to
complete Section IV of Standard Form A when submitting the applications to renew the NPDES
permits for our Archie Elledge and Muddy Creek Wastewater Treatment Plants (NPDES #s;
NC0037834 and NC0050342 respectively).
This section of Standard Form A requires information on each plant's major contributing
industries. This information is also included in our annual Pretreatment Compliance Report and
DWQ has agreed to utilize the information in this report in lieu of our having to complete Section
IV of Form A.
Thank you for your cooperation in this matter and please call me at 910-784-4700 if you have any
questions.
Sincere y:
Stanley B. Webb
Wastewater Operations Superintendent
PC: Mike Mickey; DEHNR Regional Office
Ref:let 1210.97b
GITY OF \VINSTON-SALEM
PUBLIC WORKS DEPARTMENT
P.O. BOX 2511, WINSTON-SALEM, NORTH CAROLINA 27102
December 10, 1997
Mr. Mark McIntire
North Carolina Department of Environment,
Health and Natural Resources
Division of Water Quality
P.O. Box 29535
512 North Salisbury Street
Raleigh, North Carolina 27626-0535
Subject: NPDES Permit Renewal Application
Authorization to Delete Section IV of Standard Form A
City of Winston-Salem/Forsyth County
Dear Mr. McIntire:
Per our telephone conversation of December 10, 1997. Winston-Salem will not be required to
complete Section IV of Standard Form A when submitting the applications to renew the NPDES
permits for our Archie Elledge and Muddy Creek Wastewater Treatment Plants (NPDES #s;
NC0037834 and NC0050342 respectively).
This section of Standard Form A requires information on each plant's major contributing
industries. This information is also included in our annual Pretreatment Compliance Report and
DWQ has agreed to utilize the information in this report in lieu of our having to complete Section
IV of Form A.
Thank you for your cooperation in this matter and please call me at 910-784-4700 if you have any
questions.
Sincerey:
1,1zt,4-
Stanley B. Webb
Wastewater Operations Superintendent
PC: Mike Mickey; DEHNR Regional Office
Ref:let1210.97b
DEC 1 1991
POINT SOURCE BRANCH
DIVISION OF WATER QUALITY
June 5, 1998
MEMORANDUM
TO: File
FROM: Jeff Myhra
DATE: June 5, 1998
SUBJECT: Review Notes for Winston-Salem WWTP ACC037834
WWTP plans to construct a new biosolids dewatering and truck loading facility. The new
operating equipment will allow them to dewater anaerobically digested biosolids prior to land
application. High solids centrifuges will be used to dewater polymer -conditioned biosolids to
approximately 24% total solids. Conveyors will be used to discharge dewatered biosolids
directly into trucks or into a concrete containment area used for short-term storage. Facility is
being designed to operate two shifts per day, 7 days per week.
The plant currently processes approximately 20 MGD of wastewater, with an annual average
digested biosolids production of 24 dry tons per day (DTPD). The plant is rated at 30 MGD and
the annual average digested biosolids production at this flow is projected to be 40 DTPD (55
DTPD at maximum month conditions).
The Commission began to pilot test mechanical dewatering equipment in 1996 to determine the
equipment that best meets their needs.
The evaluation showed that centrifuges would have the lowest capital cost, would require
less operator attention, better odor containment, and provide a better dewatering
performance.
Available records show the Commission is processing approximately 24 DTPD. The Dewatering
facility was sized to initially process 25 DTPD with the capability to expand the capacity of the
facility in the future to 55 DTPD which is the projected maximum solids production. The facility
will be designed to process 25 DTPD using the two installed centrifuges operating on a two -shift
per day basis. Space will be provided for a future third centrifuge and the building will be
expanded to accommodate a fourth unit. At 25 DTPD, if one unit is out of service, the remaining
centrifuge can accommodate the total solids production through increased operating hours and a
slight increase in the feed rate which will be well within the design capacity.
Proposed equipment includes:
One story reinforced concrete building with masonry walls with below grade pump
and conveyor room.
Control Room, electrical room
Space for three centrifuges; expandable to four. Two units will be installed under this
project.
Skrew conveyors under each centrifuge.
Digested sludge pumps
Chemical feed (polymer and iron salt)
Odor control scrubbing system
Bridge crane for main level room; monorail hoists for pump room.
Page 2 of 2
SCADA system.
Concrete dewatering sludge receiving pit and front-end loader operating pad
Two concrete truck -loading pads with trench drains (drain to plant influent)
Conveyor system to truck loading bay
Shuttle conveyors with steel support platform for loading trucks.
Metal conveyor conver.
Review of Metcalf & Eddy (pp 860 to 874)
Solid bowl centrifuge: Sludge is fed at a constant flowrate into a rotating bowl where
it separates into a dense cake containing the solids and a dilute stream called
"centrate." The centrate contains low -density solids and is returned to the wastewater
treatment system. The sludge cake is discharged from the bowl by a skrew feeder
into a hopper or onto a conveyor belt. The solids concentration in the cake is
generally 10 to 35 percent. The solids capture and centrate quality are improved
when solids are conditioned with polymers. Chemicals for conditioning are added to
the sludge feed line or to the sludge within the bowl of the centrifuge. Dosage rates
vary from 2 to 151b/ton of sludge (dry solids).
The major difficulty encountered in the operation of centrifuges has been the disposal
of centrate which is relatively high in suspended non -settleable solids. The return of
these solids to the influent of the wastewater treatment plant has resulted in the
passage of these fine solids through the treatment system, thereby reducing effluent
quality. The following two methods are suggested for solving this problem:
- Increased residence time or chemical conditioning. Longer residence
of the liquid stream is accomplished by reducing the feed rate or by
using a centrifuge with a larger bowl volume.
- Particle size can be increased by coagulating the sludge prior to
centrifugation.
Special consideration must be given to providing sturdy foundations and
soundproofing because of the noise and vibration associated with centrifugation.
Review of Design Support Information:
The consulting engineer provided proper documentation outlining the proposed design
components and safety features. The information provided was reviewed in conjunction with the
information presented in Metcalf and Eddy (pp 860 to 874). The majority of the review and final
approval was based on the information documented by the vendors during the pilot test period.
The information presented by the vendors (i.e. design requirements) was close to the information
specified in Metcalf & Eddy. More emphasis was placed on the information documented by the
vendors (i.e. first-hand performance data).
Staff Report Summary:
Region recommends approval of the plans for construction. The Region stated that the new
facility will enable the Elledge WWTP to dewater anaerobically digested biosolids prior to land
application or disposal in the landfill.