NC0020389_wasteload allocation_19881027

NPDES WASTE LOAD ALLOCATION
Modeler Date Rec. #
PERMIT NO.: NCOO;�O3
FACILITY NAME: 7-oWh 0 r 1` ") "' 1
Facility Status: EX [II PROPOSED
(circle one) _ Permit Status: RENEWAL MODlF"4WN__) UNPERMrrrED NEW
(circle one)
Major 1, I1tlao;,...—_—
Pipe No:
Design Capacity (MGD).
Domestic (X of Flow):
Industrial (X of Flow): 3 E 5
FACILITY MAY NEED TOXIC LIMITATIONS... PI
REFER TO RTI TOXICS REPORT
RECEIVING STREAM: F1'Cn"1(4 ei-e4l(
Class: (
Sub -Basin: () 3 -OSL & `f
Reference USGS Quad: F (please attach)
County: 1ohothr,
Regional Office: I As Fa Mo ti'al Wa Wi WS
(circle one)
Requested By: ti'�✓ Date:
Prepared 83
Reviewed B
=
u Date: d 53
y: L=L Date:
LD A7
Drainage Area (mi2 ) 10. S Avg. Streamflow (cfs): �2 0.
7Q10 (cfs) `` "' Winter 7Q10 (cfs) 30Q2 (cfs)
Toxicity Limits: IWC _ _ % (circle one) Acute /�Chronic
Instream Monitoring:
Parameters 1)0k '^^ m<G
Upstream
Downstream [
E
Location
SP, 12-11
Location!: SR 1111 Ltca6v% Z : I S
Effluent
Characteristics
SuwtMe
\1)
iM(Y' _
� A },el/
BOD5 (mg/1)
NHS N (mg/0
Z i
Z
D.O. (mg/1)
TSS (mg/0
30
3o
�,0
3a
F. Col. (/ 100ml)
1000
to DO
1000
WOO
pH (S
-
CU)
EaA IA
O.oZS
O.o 's
C�.aZs
O.a Z s
r ► /�
c��vs
0.0S
d.as
o.os

------------------- WASTELOAD ALLOCATION
Facility Name:
NPDES No.:
Type of Waste:
Status:
Receiving Stream:
Classification:
Subbasin:
County:
Regional Office:
R.equestor:
Date of Request:
Quad:
Town of Benson
NCO020389
67.5% domestic,
Mod if icat ion
Hannah Creek
C
030404
Johnston
RaRO
Harris
7/26/88
F24NE
Request No.: 47�7,9r .
APPROVAL FORM ----- ------
----
WWTP RAl.E1GN REGIONAL- OFFSC�
32.5% industrial
Drainage area:
Summer 7Q10:
Winter 7Q10:
Average flow:
30Q2:
10.500 sq mi
0.00 cfs
0.00 cfs
12. 00 cf s
0.075 cfs
-------------------- RECOMMENDED EFFLUENT LIMITS-------------------------
Wastef low (mgd) :
BOD5 (mg/1):
NH3N (mg/1):
DO (mg/1):
TSS (mg/1):
Fecal coliform (#/100m1):
PH (su):
Lead (mg/1):
Chromium (mg/1):
Chronic Toxicity sting:
summer
winter
summer
winter
1.00
1.00
1.50
1.50
14
14
RECEIVED
2
2
6
6
6
6
OCT IA
30
30
30
30
IJ�
1000
1000
1000
1000 PERMITS &
6-9
6-9
6-9
6-9
ENGINEERING
0.025
0.025
0.025
0.025
0.05
0.95
0.05
0.05
Z
Mt/ (
99%
(see attached)
---------------------------- MONITORING ----------------------------------
Upstream (YIN): Y Location: SR1211
Downstream (YIN): Y Location 1: SR1711
Location 2: I-95 culvert
Parameters: D.O., temperature, conductivity, pH, and fecal coliform
----------------------------- COMMENTS ----------------- ------------------
Recommend effluent monitoring for copper, zinc, and cyanide.
Limits are per Divisonal procedures for 7Q10=0 and 30Q2>0 streams.
See memo dated 9/30 for details regarding site surveys.
---------------------------------------------------------------------------
Recommended by: 7r Date : /0�3 90
------- - -- - ----_ _ _ ----- - — - ---
Reviewed by
Tech Support Supervisor:
Regional Supervisor:
Permits & Engineering:
Date • -- 10� Date: &116111
Date:
RETURN TO TECHNICAL SERVICES BY:

f
Facility Name J o W n 04 -&-*66A (;JGJTt' Permit # N C00 203 $1
CHRONIC TOXICITY TESTING REQUIREMENT (QRTRLY)
The effluent discharge shall at.no time exhibit chronic toxicity using test procedures outlined in:
1.) The North Carolina Ceriodaphnia chronic effluent bioassay procedure (North Carolina Chronic
Bioassay Procedure - Rdvised *February 1987) or subsequent versions:
The effluent concentration at which there may be no observable inhibition of reproduction or
significant mortality is gam% (defined as treatment two in the North Carolina procedure
document). The permit holder shall perform quarterly monitoring using this procedure to establish
compliance with the pemut condition. The fast test will be performed after thirty days from
issuance of this permit during the months of 0cf , 3om, Afte� j& j 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 month in which, it was performed, using the parameter
code TGP3B. Additionally, DEM Form AT-1 (original) is to be sent to the following address:
Attention: Technical Services Branch
North Carolina Division of
Environmental Management
P.O. Box 27687
-- Raleigh, N.C. 27611
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 any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management 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 and appropriate environmental controls, shall constitute an. invalid test
and will require immediate mtesting(within 30 days of initial monitoring event). Failure to submit
suitable test results will constitute a failure of permit condition.
7Q10 0.0 cfs
PPermited Flow 1S MGD
1 YY C% I QQVYb
Basin & Sub -basin b3oya`I
Receiving Stream H Kj-,r, , Lreek.
County 5ekuLs A
Recommended by:
**Chronic Toxicity (Ceriodaphnia) P/F at %, 0&t4 Say., A_� 1 , See Part 3 , Condition Z .

DIVISION OF ENVIRONMENTAL MANAGEMENT
October 4, 1988
mRmnRANnTTM
TO: Allen Wahab
THROUGH: Steve Tedder �r
FROM: Trevor Clements
SUBJECT: Town of Benson (NPDES No. NC0020389), Johnston County
Advanced Treatment Justification Update
As you know, Technical Services has recommended that the Town of Benson's
request for expansion to Hannah Creek be permitted with effluent limits reflect-
ing the limits of technology. A summary report was submitted to you this past
May which based our recommendation on Division procedure for discharges to
streams with a 7Q10 of zero and a positive 30Q2, and on limited information
obtained during a site visit in January, 1988. Enclosed for your review is an
updated summary justifying the need for advanced treatment at the Benson site.
The summary provides details regarding dissolved oxygen levels in Hannah
Creek both upstream and downstream of Benson's outfall. The data indicate that
the receiving waters are subject to DO standard violations both upstream and
downstream of the discharge. However, with the exception of a couple of small
pooling areas where the decay of organic matter could be contributing to low DO,
the impact on Hannah Creek appeared to be minimal. It should be noted that the
DO sags observed downstream were present when the facility was averaging less
than 5 mg/1 BOD5 and less than 1.0 mg/l NH3-N. Therefore, there appears to be
strong support for requiring Benson to treat to the limits of technology
(including tertiary filtration) to protect water quality in the receiving
waters.
Please let me know if further clarification is needed.
Attachment
JTC
cc: Bill Kreutzberger
Tom Stockton

DIVISION OF ENVIRONMENTAL MANAGEMENT
September 30, 1988
MEMORANDUM
TO: Trevor Clements
THRU: Randy Doddtb
FROM: Thomas Stockton 'J
SUBJECT: Town of Benson WWTP Expansion
The Town of Benson has requested a design flow expansion from 1.0 to 1.5 mgd
for the Hannah Creek WWTP. The USGS has provide summer 7Q10 and 30Q2 flow esti-
mates of 0.0 and 0.075 cfs, respectively. In response to past and current expan-
sion and instream assessment requests several site surveys have been conducted in
the past year. Results from these site surveys are briefly summarized below and
in the attached figure:
January 27, 1988 - Due to overgrowth the actual point of discharge was not
inspected, however, Hannah Creek was found to be very swampy with little flow.
Just downstream at SR1171 the Creek was murky green and the stream banks were cov-
ered with duckweed. The SR1171 bridge channelized the stream which appeared to
remain channelized down to the I-95 culvert (approximately 0.7 miles). The
stream tends to pool and stagnate at the culvert. The water was still murky
green and duckweed was noted collected on the stream banks. Hannah Creek at
SR1159 (approximately 3.5 miles from the point of discharge) was clear and flow-
ing but somewhat swampy. Dissolved oxygen measurements taken at the road cross-
ings were at approximately 70% of saturation.
August 8, 1988 - The point of discharge was inspected and was found to be a
braided hardwood swamp. Several tributaries meet at the discharge location pro-
viding a surprising amount of flow. D.0 was measured at less than 4 mg/l both
upstream and downstream of the discharge.
September 12, 1988 - The length of the stream from the discharge point to
SR1711 was inspected with flow and physical measurements taken. The lowest D.0
(4.2 mg/1) was measured upstream of the discharge. All background D.O. measure-
ments were less 5.5 mg/l. A site further downstream, SR1159 (3.5 miles from the
discharge), was also inspected. This area appeared to constitute a true bottom -
land hardwood swamp.
The braided channel, low flow nature of Hannah Creek make a modeling analysis
of the water quality impact of increase loading very uncertain.. Low dissolved
oxygen levels are occurring during the summer months in Hannah Creek, both
upstream and downstream of the discharge. This situation, coupled with the phys-
ical characteristics of the stream, make compartmentalizing the causes of the
deficit intractable without a significant commitment of resources. However,
background levels of dissolved oxygen are low and the relatively high quality
effluent (see attached DMR data) it doesn't appear to be significantly adding to
the D.O. deficit.

i
Based on the above observations I recommend that current Divisional proce-
dures for expansions to NSW classified low flow streams, BODS of 5 mg/l, NH3 of 2
mg/l and Total Phosphorus of 2 mg/l, be applied. Limits for lead and chromium
and monthly effluent monitoring for copper and zinc are recommended based on
headworks analysis and DMR data (see attached).-

Sta
O1
EFF
02
03
04
05
06
07
08
09
10
11
12
September 12, 1988
DO Temp Condo Flow
4.2
21.5
90
7.2
26.0
270 2.0
5.1
22.0
65 9.4
5.2
22.0
90
6.2
24.0
180
5.7
22.0
130
5.4
21.0
5.4
22.0
100
5.7
22.0
120
5.4
21.0
5.4
22.0
12.1
4.7
22.0
2.5
21.0
_
August 8, 1988
Sta
----------------------
DO
Temp
01
3.4
24.0
02
5.6
25.0
10
5.1
26.0
11 (s)
3.7
25.0.
11 (b)
0.0
25.0
13
5.2
24.0
January 22, 1988
Sta
----------------------
DO
Temp
10
8.9
7.5
11
7.9
7.0
SR1159
8.1
6.3
Benson WWTP Site Surveys Results
Stream miles
EFF - 10: 0.7 miles
EFF - 11: 1.4 miles
09 - EFF: 0.5 miles
NftJIl VCL111 V11 C11111V1
swampy area
O1 station number

15
14
13
12
11
10
9
8
7
6
5
4
3
Benson WWTP - Hannah Creek
Instream D.O.
❑ Upstream
SR1111- 0.5 miles
upstream of dis-
charge
+ Downstream
SR1711 - 0.7 miles
downstream of discharge

DIVISION OF ENVIRONMENTAL MANAGEMENT
May 23, 1988
MEMORANDUM
TO: Allen Wahab
Construction Grants
THROUGH: Steve Tedderi�
Trevor Clement
Randy Dod�
FROM: Thomas Stockton��
Technical Services Branch
SUBJECT: Town of Benson WWTP AT Checklist
NPDES No. NC0020389
Johnston County
The Town of Benson WWTP discharges to Hannah Creek (030404) in Johnston
County. The USGS has provided 7Q10 and 30Q2 flow estimates of 0.0 cfs and 0.075
cfs, respectively, for Hannah Creek at the point of discharge. In June 1987 the
Technical Services Branch received wasteload allocation requests from the Town
for modification of the facility's design capacity from 0.825 to 1.0 and 1.274
mgd. The Town also requested effluent limits for two alternative discharge
sites: the Neuse River at I-95 and Mingo Swamp (Cape Fear River Basin). At the
time Nutrient Sensitive Waters (NSW) classification was pending for the Neuse
River Basin. The Town indicated that the Mingo Swamp site may be preferable
since phosphorus removal is not be required in the Cape Fear River Basin. The
Neuse River basin has since been classified NSW which would require the facility
to comply with a total phosphorus limit of 2 mg/l at the Hannah Creek and Neuse
River sites.
Due to the low flow and swampy nature of Hannah Creek a modeling analysis of
the proposed expanded flows was not undertaken. To address the expansion issue
and to field check the appropriateness of the proposed Mingo Swamp and Neuse
River discharge sites, a site survey was conducted on January 22, 1988. This
survey was conducted during a high flow period which must be taken into consider-
ation when reviewing the following observations.
Site Survey Observations
Hannah Creek at the point of discharge is very swampy with little flow. Just
downstream of the discharge (SR 1171) the Creek was a murky green with algae col-
lected on the banks. The algae likely originates in the facility's polishing
pond which was noted to have a 50% algal mat coverage.

Two downstream sites were also visited. Hannah Creek from SR 1171 to I-95
(approximately 0.7 miles) appeared to be fairly channelized. The water was still
murky green at I-95 and algae was also noted collected on the banks. The water
tends to pool in front of the culvert that carries the stream under I-95. During
low flow periods water may stagnate here. The velocity appeared to increase in
Hannah Creek at SR 1159 (approximately 3.5 miles from the discharge point),
though the channel was not well defined, and the water was much clearer.
The proposed Mingo Swamp site (near SR 1102) is very swampy but there was some.
flow (likely due to the channelization created by the bridge). A defined channel
was not evident and the stream bottom was covered with leaves., reinforcing the
1978 USGS 7Q10 estimate of 0.0 cfs. Approximately 0.9 miles downstream the
stream is dammed and forms a cypress pond. Based on these observations the Town
was discouraged from further consideration of this site for a discharge.
The proposed Neuse River site was also visited. The flow in his section of
the Neuse River is controlled by the minimum release from Falls Dam and the Corp6
of Engineers target flow at Smithfield of 254 cfs in the summer and 180 cfs in
the winter. Initial QUAL2E modeling analysis indicated that secondary limits may
be appropriate at this site, however, phosphorus removal would be required.
Recommendations
Self -monitoring data indicate that dissolved oxygen suppression below 5 mg/1
is occurring in Hannah Creek downstream of the discharge during the summer months
(see attached graph). This may be due to diurnal swings created by the apparent
algal population (instream samples were typically taken before 10:00 am). Based
on these observations the Division made the following recommendations to the
Town:
1) Mingo Swamp is unsuitable as a discharge site.
2) The Neuse River site may be a risk if this option is only cost effective
for -treatment at a secondary level due to the Division's increasing
awareness of water quality problems in the Neuse River and NSW
classification for the basin.
3) In consideration of the above conclusions the Hannah Creek site appears to
be the most desirable alternative if the current level of treatment is
maintained.
A permit was issued in March 1988 allowing an expanded design capacity of 1.0
mgd without construction of additional facilities. The ability of Hannah Creek
to assimilate additional oxygen demanding wastewater is extremely limited. The
impacts of the proposed additional 0.5 mgd of wastewater can be mitigated if
effluent limits of 5 mg/l for BODS and 2 mg/l for NH3-N can be maintained.

I
1�
1?
12
11
10
9
8
7
6
5
4
3
1
Benson WWTP - Hannah Creek
Instream D.O.
❑ Upstream + Downstream

v 304 0q
DIVISION OF ENVIRONMENTAL MANAGEMENT
May 23, 1988
MFMnR A NnI rM
TO: R.W. Van Tilburg
Raleigh Regional ice
THROUGH: Steve Tedder
Trevor Clemen s
Randy Doddt_
FROM: Thomas Stockton��
Technical Services Branch
SUBJECT: Town of Benson WWTP Instream Assessment
NPDES No. NC0020389
Johnston County
The Town of Benson WWTP received a permit modification in March 1988 which
allowed an increase in design capacity from 0.825 to 1.0 mgd and is in the pro-
cess of applying for advanced treatment funding to upgrade the facility to 1.5
mgd. The permitted increase in design capacity was justified based on continued
compliance with permit limits (other than flow) at flow rates up to 1.08 mgd.
However, due to the facility's non-compliance with the flow limit the Raleigh
Regional Office has requested that the Technical Support Unit perform an instream
assessment for an additional 0.279 mgd of domestic and industrial wastewater.
The facility discharges to Hannah Creek (030404) in Johnston County. Model-
ing analyses typically performed by the Technical Support Unit for instream
assessments and WLAs use the 7Q10 flow statistic as the critical flow condition.
The USGS has provided 7Q101and 30Q2 flow estimates of 0.0 cfs and 0.075 cfs,
respectively, for Hannah Creek at the point of discharge. Since modeling tech-
niques employed by the Technical Support Unit assume positive flow,these modeling
techniques are inappropriate for "low" flow streams. Based on this conclusion
Divisional procedures for "low" flow streams have been developed which stipulate
that an existing discharger with no wasteflow changes receives its existing per-
mit limits and proposed expansions receive summer/winter BODS and NH3-N limits of
5 and 2/10 and 4 mg/1. This procedure was recently applied to Benson's request
for expanded design capacities of 1.0 and 1.274 mgd (9/27/87).

To further address the Town's requests for expanded design capacity, alterna-
tive discharge sites, and in light of the inappropriateness of a modeling analy-
sis for the Hannah Creek expansion the Technical Support Unit conducted a site
survey to field check the ability of Hannah Creek, Mingo Swamp, and the Neuse
River to handle the expanded flows. This site survey indicated that Hannah Creek
may be able to assimilate the expanded wasteflows in consideration of the high
level of treatment the facility was attaining (see attached memo). DMR data
indicates that the facility provides good effluent quality even when overloaded
(see attached). However, the facility failed a chronic toxicity screening
performed by the Aquatic Toxicology Group in November 1987 and has failed to
submit self -monitoring toxicity data.
It is Technical Services recommendation that a course of action be left to
the discretion of the Director. However, it is also recommended that:
1) Since the requested JOC flow constitutes a greater than 25% increase
over the existing design capacity that no further flow increases be
considered,
2) The Judicial Order should contain a toxicity monitoring requirement and
should contain a clause that allows the Division to place the
facility on moratorium based on monitoring results,
3) Failure to submit toxicity self -monitoring data constitutes a permit
violation which the region should pursue.
Please contact me should you have questions.
cc. George Everett
Kent Wiggins
Steve Reid
Ken Eagleson

REQUEST FORM FOR IN -STREAM ASSESSMENT FOR 67B
NAME OF FACILITY Town of Benson WWTP SUBBASIN 03.04.04
COUNTY Johnston
REGION Raleigh DESIGN FLOW 0.825 MGD
RECEIVING STREAM Hannah Creek
BACKGROUND DATA:
A. Why is SOC needed? (Facility is out of compliance with
which effluent limits?) Flow
B. History of SOC requests:
1. Monthly Average waste flow
prior to any SOC _
Time period average 87/01
2. Previously approved SOC's: None
Date: flow:
Date: flow:
total of previously approved SOC:
flow:
3. Flows lost from plant
(facilities that have gone
off line)
4. Current SOC request
5. Total plant flow post-SOC
(sum of original flow and
SOC flow minus losses)
1.04
thru
flow: 0
flow: 0.279
flow: 1.283
MGD
87/03
MGD
MGD
ZWE
MGD
MGD
MGD
6. Is this an accurate flow balance for plant? Why/why not?
Yes. This Wastewater Treatment Plant has been exceeding
the final effluent limitation for flow. The Raleigh
Regional Office proposes placing a limit of 1.3 MGD in
the JOC.

C. Please attach DMR summary for past year for all permitted
parameters. If possible, include reports from previous years
if facility has been under SOC for more than a year.
CURRENT SOC REQUEST:
A. Request is for domestic or industrial waste? It is is a
combination, please specify percentages.
Industrial 0.2 MGD 72%
Domestic 0.079 MGD 28%
B. What type of industry? Please attach any pertinent data.
Chicopee - nonwoven textile fabric for disposable hospital
gowns. They add blue color to the fabric. Daily Average
Flow = 325,000 gpd Non-categolical Industry.
C. The region proposes the following SOC limits:
BOD5
NH3
DO
TSS
fecal Coliform
pH
other parameters
�7-
mg / 1
2
mg/l
5
mg/1
30
mg/1
1,000
#/100 ml
6-9
SU
Flow 1.3 MGD
D. What is the basis for these limits?
The city has asked for additional flow to 1.274 MGD. They
have not asked for relaxation of other parameters.

I
State of North Carolina
Department of Natural Resources and Community Development
Division of -Environmental Management - ._ -- - -- ----- -r-- -
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor
S. Thomas Rhodes, Secretary
January 28, 1988
Arthur L. Kennedy
L.E. Wooten and Company
120 N. Boylan Avenue
Raleigh, N.C. 27603
Dear Mr. Kennedy:
R. Paul Wilms
Director
This letter is in response to your request for development of effluent limits
at proposed Neuse River and Mingo Swamp discharge sites for the Town of Benson's
wastewater treatment plant. The Technical Services Unit of DEM conducted a site
survey and modeling analysis of the current Hannah Creek and proposed sites
resulting in the following recommendations.
The Mingo Swamp was found to be an inappropriate site for effluent discharge
due to the low flow nature of the stream and a downstream cypress pond. The
Neuse River site offers considerable dilution, resulting in secondary limits
(BOD5 of 30 mg/1). However, it should be noted that this does not guarantee that
effluent limits will not be made more restrictive in the future. As DEM's knowl-
edge of water quality throughout the Neuse River increases, we are learning -of
areas in need 'of pollutant loading reduction. Given the length of pipe needed to
reach the Neuse, it may be a risk if this option is only cost effective for
treatment at a secondary level.
Considering the unsuitability of the Mingo Swamp site and the current level
of treatment Benson's plant provides, remaining at the Hannah Creek site appears
to be the most desirable alternative. As you know, NSW classification pending
for the Neuse River basin will likely require some level of phosphorus removal in
the near future at the Hannah Creek and proposed Neuse River site.
Pollution Pmwntion Pars
P.O. Box 27697, Raleigh, North Carolina 27611-7697 Telcphonc 919-733-7015

Should you have any questions regarding this analysis, please contact me at
[phone].
Sincerely,
Thomas Stockton
TBS/tbs
cc: Allen Wahab
Carolyn McCaskill

DIVISION OF ENVIRONMENTAL MANAGEMENT
April 22, 1988
MEMORANDUM
TO: Trevor Clements, Supervisor
Technical Support Unit
Water Quality Section
THRU: Allen Wahab, Supervisor
Local Planning Management Unit
(
FROM: Daniel Blaisdell /'v ""�
Local Planning Management Unit
SUBJECT: Benson Portion
Dunn, Benson, Erwin 201 Facilities Plan
AT Checklist
Project No. C370417-01
This is to request that an AT Checklist be completed for the
subject project. The selected alternative is to expand the existing
0.825 mgd oxidation ditch to 1.5 mgd and continue discharging at the
present point on Hannah Creek. The current permit limits are 0.825 mgd
with BOD5 5/7 winter/summer, NH3 2/2 winter/summer and TSS 30. For
your convenience I have enclosed a topographic map depicting the
current discharge point.
Please return the completed checklist and related documentation
by May 25, 1988 so that we can complete our portion of the AT review
and conclude the overall review of the Dunn, Benson, Erwin 201
Facilities Plan Amendment.
Please call me at 3-6900 if you need more information.
DMB/jh
Enclosure
cc: Raleigh Regional Office
Reg Sutton
LPMU
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DIVISION OF ENVIRONMENTAL MANAGEMENT
January 27, 1988
MEMORANDUM
TO: Trevor Clements
FROM: Thomas Stockton
Steve Zoufaly
SUBJECT: Town of Benson Site Survey
The Town of Benson currently discharges to Hannah Creek (030404) in Johnston
County. In June 1987 Benson requested a permit modification for increased waste -
flow from 0.825 to 1.0 and 1.274 mgd. Hannah Creek falls under Divisional proce-
dures for "zero" flow streams (7Q10=0.0 cfs and 30Q2=0.075 cfs), therefore, sum-
mer/winter BODS and NH,-N limits of 5 and 2/10 and 4 were recommended.
Benson has requested effluent limits for two alternative discharge sites 1)
the Neuse River and 2) Mingo Swamp (Cape Fear Basin). Due to the likelihood of
phosphorus limits for the Neuse River Basin in the near future, Benson indicated
that the Mingo Swamp may be preferable. A site survey was performed on January
22, 1988 to field check the appropriateness of the current and proposed sites as
discharge points. This survey was conducted during a high flow period which must
be taken into account when considering recommendations.
Benson WWTP appears to have a high quality effluent. BODS and NH_,-N concen-
trations average 2.24 and 0.66 mg/l, respectively, from December 1986 to November
1987 (see attached DMR data for 1987). Treatment includes an oxidation ditch and
polishing pond. Hannah Creek at the point of discharge is very swampy with
little flow. Just downstream of the discharge (SR 1171) the Creek was a murky
green and algae had collected on the banks. The algae probably comes from a pol-
ishing pond that was about a third covered with an algal mat. D.O, temperature,
and conductivity were measured at 8.7 mg/l, 7.5'C, and 105 µhmo, respectively.
Benson upstream/downstream DMR data indicate the discharge may be impacting D.O.
concentrations during -summer months (see attached graphs).
Two sites downstream were also visited. Hannah Creek from SR 1171 to I-95
(approximately 0.7 miles) appeared to be fairly channelized. The water was still
murky green at I-95 and algae was noted collected on the banks. The water tends
to pool in front of the culvert under I-95. During low flow periods water may
stagnate here. Hannah Creek at SR 1159 (approximately 3.5 miles from the dis-
charge point) had good flow, though still swampy, and the water was much clearer.
This site likely becomes dry during the summer.
The proposed Mingo Swamp site (near SR 1102) is very swampy but there was
some flow. A defined channel was not evident and the stream bottom was covered
with leaves, reinforcing a 1978 USGS 7Q10 estimate of 0.0 cfs. D.O., tempera-
ture, and conductivity was measured at 8.1 mg/l, 6.8°C, and 90 phmo, respec-
tively. Approximately 0.9 miles downstream the stream is dammed and forms a
cypress pond. Downstream of the cypress pond (SR 1107) the stream is more chan-
nelized but very little flow was noted. This site did not appear suitable as a
discharge site.
I

a
The proposed Neuse River site was also visited. Initial modeling analysis
using the Neuse River QUAL2e model indicates that secondary limits may be appro-
priate for the Neuse River site. The Falls to Smithfield model was extended 13
miles and the assumption was made that river characteristics modeled in Reach 7
remained constant down to Polecat Branch. Loadings at Middle Creek were based on
the Middle Creek Level B model with Cary and Fuquay Varina at full expansion.
In summary, Mingo Swamp is not an appropriate site for effluent discharge.
The Neuse River site offers considerable dilution, however, considering the level
of treatment the Benson plant provides and the cost of piping to the Neuse, this
site doesn't appear to offer many advantages. NSW classification for the Neuse
Basin will likely require Benson to remove phosphorus in .the near future at the
Neuse River and Hannah Creek sites. This is offered with some reservations. D.0
problems are occurring in Hannah Creek below the treatment plant during the sum-
mer, though treatment is providing an effluent with near background concentra-
tions. D.O. suppression may be due to diurnal swings created by the large algal
population (instream samples were typicaily'takeri before 10:00 AM). The role the
algal population, natural swamp conditions, and flow conditions play in the sup-
pression of D.O. need to be addressed.

9
8.5
8
7.5
7
6.5
6
5.5
5
4.5
Neuse River QUAL2E Model
Benson WWTP @ secondary limits
<-- Burlington Ind
<-- Wake Forest WWTP @ 6 mgd
-- Central
\�jJohnston Co
' -- Raleigh WWTP 60 mgd
<-- Milburnie Dam
'ITiTfTf"TrITflTrf
'L1 5.0 16.6 15.0 20.0 25.0 30.0 35.0 40.0 45.0
FALLS DAM -------------> POLECAT BRANCH
@ 1.27

3922
25'
ZO'
`v `32' 30"
so j
724
30 Mi
I MILE
c
QUADRANGLE` LOCATION
Ff
a2 Se�-rH SNNs-wa
y� Sc..woOL_ WM
�96W_.04 WWTP
35°22'30„
725 J �,NTERIOR-GEOIOutIALSURVEY,NESTON,VIR(iiN1A-IY19 78*30'
LJ 726000, E.
ROAD CLASSIFICATION �oG
Primary highway, Light -duty road, hard or o
hard surface improved surface - _= __1 S,
s
Secondary highway, s�
hard surface — — Unimproved road So
o,
Interstate Route ; U. S. Route State Route
BENSON, N. C. MASTER FILE
N3522.5—W7830/7.5
1973
AMS 5254 1 NE -SERIES V842

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CDco p T DUNN 9 Mi. f V BENSON 3.4 Mi. ` !�
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234

UNITED STATES
DEPARTMENT OF THE INTERIOR
GEOLOGICAL SURVEY
35'
3q
27'

m
1100 q / Jz
Diet.
from
Point
Width
Depth
Raw-
olu-
tfoe*
TiesInitial
in
S*coads
VELOCITY
Area �Dietharg
At
Point
Me*n in
Verti—I
I
.D
DID
11
3,0
2'_
0
.Z�s
2
�(00
I <<
Z
q fl
Z 14'io
. l
r;
y
2
2 ,
? U
Lfo
�
2
L qSS
I
�
I
i
LJ-4 1-�
Diet.
from-
Initial
Point
Width
Depth
olu-
tione
VELOCITY
Ties
in AC Mean in
second • Point Vertical
Are* Discharge
I I
J
,y2S
5S
( A
3.7
I,140
I
i
I

DIVISION OF ENVIRONMENTAL MANAGEMENT
INTENSIVE SURVEY
DISCHARGE MEASUREMENT
Station #
Sub -basin
Survey Area
Time Start
Stage Start
Width
VELOCITY
Station Location:
R. P. Location:
Storet #
Date
Time End
Stage End
Area
DISCHARGE
DIVISION OF ENVIRONMENTAL MANAGEMENT
INTENSIVE SURVEY
DISCHARGE MEASUREMENT
Station A
Sub -basin
Survey Area
Time Start
Stage Start
Width
VELOCITY
Station Location:
R. P. Location:
Comments: Comments:
Storet #
Date
Time End
Stage End
Area
DISCHARGE

�MNEFi:�
Y) �-NvZ.
Lb
Dist.
from
Initial
Point
Width
Depth
Rav-
olu-
tiros
Time
is
Second
VM=ITY
Ara
DischorR
At
Point
Kean in
Vertical
7-
`f
b, Z
i
p,�
U• I
ko
0i3z5
6.S
0, Z
0.335
'v.5
0.la
u
,
0"1
0,
uS
0.2
_)
D
012S
D.z02.5
2
6A
I�
o .z
LI
o
2,JU
\033 q (Iz
Dist.
from
Initial
Point
Width
Depth
Rev-
olu-
done
VELOCITY
Tine
Tim
in At Mean in
Point Vertical
Area Discher;e
O,U�i
ZS
.4
105
I,o15
i
I

DIVISION OF ENVIRONMENTAL MANAGEMENT
INTENSIVE SURVEY
DISCHARGE MEASUREMENT
Station #
Sub -basin
Survey Area
Time Start
Stage Start
Width
VELOCITY
Station Location:
R. P. Location:
DIVISION OF ENVIRONMENTAL MANAGEMENT
INTENSIVE SURVEY
DISCHARGE MEASUREMENT
Storet #
Station #
Date
Sub -basin _
Survey Area
Time End
Time Start
Stage End
Stage Start
Area
Width
DISCHARGE VELOCITY
Station Location:
R. P. Location:.
Comments: Comments:
Storet #
Date a1 117 /��
Time End
Stage End
Area
DISCHARGE

INTENSIVE SURVEY FIELD DATA
Sub -basi r;:
Survey Area:
Date:
Station #
Location
Time
Temp.
D 0
pit
Cond.Fta
00010
00300
0040
000095
r
i
i

YA �d
3 SOD s
95

`, ' INTENSIVE SURVEY FIELD DATA
Sub -basin: Date: i
Survey Area:
r'
Station #
Location
Time
Temp.
00010
D 0
00300
may,
00400
Cond.
90095
Stage
00065
PAD
I
i
I
I
I

DIVISION OF ENVIRONMENTAL MANAGEMENT
January 19, 1988
MEMORANDDUM
TO e Trevor Clements
From: Thomas Stockton
Steve Zouflay
Subject: Town of Benson Site Survey
The Town of Berson currently discharges to Hannah Creek:: (030404) in Johnston
County. In June 1987 Benson requested a.. permit modification for increased waste -
flow from 0.825 to 1.0 and 1.274 mgd. Hannah Creek; falls under Divisional proce-
dures for "zero" .flow streams (010=0.0 cfs and 30Q2=0.075 Us), therefore, sum-
mer/winter BOO, and NHa-N limits of 5 and 2/10 and 4 were recommended.
Benson has requested effluent limits for two .alternative discharge sites, 1)
the Neuse Fiver and 3) Mingo Swamp (Cape Fear Basin). Due to the likelihood of
phosphorus limits for the P,leuse River- Basin in the near future, Benson indicated
that the Mingo Swamp may be preferable.
Initial modeling analysis using the !Meuse giver QUAL'e model indicates that
secondary limits may be appropriate for the Neus,e giver site. The Falls to
Smithfield model was extended 13 miles and the assumption was made that river
characteristics modeled in Reach 7 remained constant down to Polecat Branch.
Loadings at Middle Creek: were based on the Middle Creek: Level B model with Cary
and Fuquay Marina at full expansion.
No initial modeling has been performed for the Mingo Swamp site due to the
lacks of an existing model and field data. It is recommended that a reconnais-
sance survey be performed at the current and proposed discharge sites to field
check:: the appropriateness of each site as a discharge point and the appropriate-
ness of model assumptions for each site. Due to the current high flow condi-
tions, the site surveys will be limited to walking the streams to check; for areas
of pooling and/or slowing moving water.
The site survey has tentatively been arranged for Friday January 23, 19389
with Steve 2oufaly, Thomas Stockton, and Jim Fisher participating.

DIVISION OF ENVIRONMENTAL MANAGEMENT
January 15, 1988
MEMORANDUM
TO: Arthur Mouber
THROUGH: Steve Tedder
FROM: Trevor Clements
SUBJECT: Comments regarding Town of Benson request for permit modification
NPDES No. NC0020389
I have reviewed the request by the Town of Benson to waive their requirement
for monitoring of the following metals: Cr, Cu, Pb, and Zn. Their current
NPDES permit wasteload allocation is based upon the assumption that the facility
can receive between 26 and 39 percent of its wastewater from industrial sources.
Since the permit reflects 5 years into the future, and not only the current
situation, I would not recommend eliminating monitoring. However, if the Town
can submit 6 consecutive months of monitoring data showing undectable levels
of these metals (detection limits should reflect either APHA Standard Methods
or EPA Methods Manual), then Technical Services would consider reducing their
monitoring requirement to a quarterly or semi-annual basis. In addition, it
should be noted that such monitoring (i.e. prior to introducing industrial
sources) may be of great benefit to the Town as baseline data for comparison
after industries come on line.
Please let me know if I can be of further assistance in this matter.
JTC
CC: Carolyn McCaskill
Tom Stockton

Y
10�* OF SC4,
v
l� C ARO
TOWN OF BENSON
P. O. BOX 157
NORTH CAROLINA
27504
MAYOR �yy1r't,y.
CHARLES W. MATTHEWS Ems•. .�1 •.v:.:
t'
Mr. Arthur Mouberry
NC Division of Environmental Mangement
P.O. Box 27687
Raleigh, North Carolina 27611-7687
RE: NPDES Permit NCO020389
Benson, North Carolina
Dear Mr. Mouberry:
` 1
lb�-.
7rCwV1C4J S£R i588
V I CAS Bk4NCH
January 6, 1988
COMMI§6IONER•
DEVAN BARBOUR. III
NATHAN B. BLACKMAN
GEORGE T. HUDSON
J. W. PARRISH. JR.
TOWN ADMINISTRATOR
KEITH R LANGDON
TOWN CLERK
CAROLYN A NORDAN
On or about December 9, 1987s the Town of Benson received a copy of the
draft NPDES Permit for our wastewater treatment plant. On the following day,
John Alt, Sr., our plant superintendent and Buck Kennedy of The Wooten Company
contacted you regarding -.the new wastewater parameters for which we will be
required to test on a periodic basis. As you explained, several of these para-
meters are new not only for our permit but for all other permits in the State
as well.
Iri reviewing the sampling requirements, we noticed we will be required to
sample and test for lead, copper, zinc and total chromium - all being heavy
metals.. To the best of our knowledge., -there are no industrial or commercial
-- --- --.establishments discharging into --our- system* that would have these metals in any
measurable quantity. As you or your staff may have noted from our pretreatment
program documents,.the Town has established limits for some of these parameters
but it was done by "default". In effect, we did so to be protected just in case
someone was to discharge a waste containing one or more of these metals to our
system in the future. Therefore, since our records show no history of these
metals being discharged into our sewer system and we know of no discharger that
may even be suspected of discharging these metals,. we respectfully request the
monitoring requirement for these heavy metals (lead, copper, zinc and total
chromium) be deleted from the final draft of our NPDES Permit.
Thank you for your consideration'of this request. Please contact either
the Town or The Wooten Company if you have any questions regarding this matter.
KRL/JJ
Sinc rely,
4J
4�TH R. LANG O
Town Administra or

SUMMER
'
MIDDLE
CREEK PROFILE
FOR USE
IN NEUSE.QUAL2E MODEL
Seg
# | Reach # 1
5eg Mi 1
D.O.
/ CBOD
1 NBOD |
Flow |
1
1
0.00
6.01'
9.91
8.91
25.08
1
1
0.20
5.94
9.82
8,79
25.08 .
1
1
0.40
5.88
9.74
8.67
25.09
1
1
0.60
5.82
9.65
8.56
25.09
1
1
0.80
5176
9.57
8.45
25.10
1
1
1.06
5.72
9.49
8.34
25.10 '
1
1
1.20
5.67
9.41
8.23
25.10
1
1
1.40
5.64
9.33
8.12
25^11
1
1
1.60
5^60
9.25
8.01
25,11
1
2
1.60
5.60
9.25
8.01
25.11
1
2
1.70
5.53
9.19
7.92
25.11
1
2
1.80
5.46
9.13
7.83
25.12
1
2
1.90
5"39
9.07
7.74
25.12
1
2
2.00
5.33
9.01
7.65
25.12
1
2
2.10
5.27
8.95
7.57
25.12
1
2
2.20
5.21
8.89
7.48
25.12
1
2
2.30
5.16
8.83
7.40
25.13
1
2
2.40
5.11
8.77
7.31
25.13
1
2
2.50
5.06
8.71
7.23
25.13
1
3
2.50
5.06
8.88
7.18 .
25.31
1
3
2.70
5.17
8.76
7.02
25.32
1
3
2.90
5 27
8.64
6.86
25.32
1
3
3.10
5.36
8.52
�
6.71
25.32
1
3
3,30
5.44
8.40
6.56
25.33
1
3
3.50
5.52
8.29
6.41
25.33
1
3
3.70
5.59
8.17
6.27
25.34
1
3
.90
5.66
8.06
6.13
25.34
2
1
0.00
6.00
32.00
0.00
0.04
2
1
0.10
5.79
30.52
0.00
0.04
2
1
0.20
5.73
29.11
0.00
0,04
2
1
0.30
5,75
27.76
0.00
0.04
2
1
0.40
5.80
26.47
0.00
0.04
2
1
0.50
5.88
25.25
0.00
0.04
2
2
0.50
5.93
28.25
0.00
0.07
2
2
0.70
5.81
26.33
0.00
0.07
2
2
0.90
5.84
24.54
0.00
0.07
2
2
1.10
5.94
22.88
0.00
0.07
2
2
1.30
6.05
21.33
0.00
0.07
2
2
1.50
6.18
19.88
0.00
0.07
2
2
1.70
6.29
18.53
0.00
0.07
3
1
0.00
5.66
8.09
6.11
25.41
3
1
0.20
5.72
7.98
5.97
25.43
3
1
0.40
5.78
7.86
5.84
25.44
3
1
0.60
5.84
7.75
5.71
25.46
3
1
0.80
5.89
7.64
5.58
25.47
3
1
1.00
5.95
7.54
5.45
25.49
3
1
1,20
5.99
C43
5.33
25.51
4
1
0.00
6.01
16.34
13.36
9.40
4
1
0.20
6.36
16.18
13.23
9.40
4
1
0;40
6.61
16.02
13.11
9.40
4
1
0.60
6^78
15.86
12.98
9.40
4
1
O.bO'
6.90
15.70
12.85
9.40
4
1
4.00
6.99
15.54
12.73
9.40
4
1
1.20
7.05
15.39
12.61
9.40
4
1
1.40
7.10
15.23
12.48
9.40
4
1
1.60
7.13
15.08
12.36
9.40
4
1
1.80
7.16
14.93
12.24
9.40
4
^
1
"
2.60
m "^
7.18
- n"
14.78
41 'n
12.12
"n "^
9.40
" ^^

1 2.60
7.22
14.34
11.77
9.40
1 2.80
7.23
14.20
11.66
9.40
2 2.80
7.20
14.49
11.47
9.56
2 2.90
7.20
14.42
11.41
9.56
2 3.00
7.20
14.34
11.35
9.56
2 3.10
7.21
14.27
11.28
9.56
2 3.20
7.21
14.20
11.22
9.56
2 3.30
7.22
14.12
11.16
9.56
2 3.40
7.22
14.05
11.10
9.56
2 3.50
7.22
13.98
11.05
9.56
1 0.00
6.33
9.22
6.89
35.06
1 0.10
6.33
9.16
6.82
35.06
1 0.20
6.32
9.11
6.76
35.06
1 0.30
6.32
9.06
6.70
35.06
1 0.40
6.32
9.01
6.64
35.06
1 0.50
6.32
8.96
6.58
35.06
1 0.60
6.32
8.91
6.52
35.06 .
2 0.60
6.31
9.06
6.47
35.30
2 0.70
6.31
9.01
6.42
35,30
2 0.80
6.32
8.96
6.36
35.30 '
1 0.00
5.00
32.00
0.00
0.71
1 0.10
5.95
31.58
0.00
0.71
1 0.20
6.50
31.16
0.00
0.71
2 0.20
6.50
31.16
0.00
0.71
2 0.30
6.93
30.59
0.00
0.71
2 0.40
7.13
30.03
0.0O
0.71
2 0.50
7.22
29.47
0.00
0.71
2 0.60
7.27
28.93
0.00
0.71
2 0.70
7.30
28.40
0.00
0.71
2 0.80
7.32
27.88
0.00
0.71
2 0.90
7.33
27.37
O.00
0.71
2 1.00
7.35
26.87
0.00
0.71
2 1.10
7.36
26.37
0.00
0.71
3 1.10
7.36
26.37
0.00
0.71
3 1.30
6.99
25.56
0.00
0.71
3 1.50
6.79
24.77
0.00
0.71
3 1.70
6.70
24.00
0.00
0.71
3 1.90
6.66
23.26
0.00
0.71
3 2.10
6.66
22.54
0.00
0.71
3 2.30
6.67
21.84
0.00
0.71
3 2.50
6.70
21.16
0.00
0.71
3 2.70
6.73
20.51
0.00
0.71
3 2.90
6.76
19.87
0.00
0.71
3 3�10
6.80
19.26
0.00
0.71
3 3.30
6.83
18.66
0.00
0.71
3 3.50
6.87
18.08
0.00
0.71
3 3.70
6.90
17.52
0.00
0.71
1 0.00
6.33
9.13
6.23
36.01
1 0.20
6.21
9.03
6.12
36.01
1 0.40
6.09
8.93
6.01
36.02
1 0.60
5.99
8.84
5.90
36.02
1 0.80
5.89
8.75
5.80
36.02
1 1.00
5.81
8.65
5.69
36.03
1 1.20
5.72
8.56
5.59
36.03
1 1.40
5.65
8.47
5.49
36.04
1 1.60
5.58
8.38
5.39
36.04
1 1.80
5.52
8.30
5.29
36.04
1 2.00
5.46
8.21
5.20
36.05
1 2.20
5.41
8.12
5.11
36.05
1 2.40
5.36
8.04
5.01
36.06
1 2.60
5.32
7.95
4.93
36.06
1 2.80
5.29
7.87
4.84
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6.93
3.89
36.11
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3.82
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6.73
3.75
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1 5.80
5.12
6.71
3.69
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1 6.00
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6.64
3.62
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1 6.20
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6.57
3.56
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6.50
3.49
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5.15
6.49
3.48
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5.16
6.42
3.42
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5.17
6.35
3.36
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5.19
6.29
3.30
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5.20
6.22
3.24
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5.22
6.15
3.1.8
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5.23
6.09
3.13
36.25
2 7.80
5.25
6.03
3.07
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2 8.0
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5.96
3.02
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2 8.20
5.29
5.90
2.96
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5.84
2.91
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13.17
0.43
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12.82
0.41
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12.47
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12.13
0.37
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6.53
1.1.80
0.35
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5.86
2.90
36.38
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5.80
2.85
36.38
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36.39
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2.75
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5.56
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0.57
37.86
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0.55
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L. E. W®TEN AND COMPANY
120 N. BOYLAN AVENUE RALEIGH, NORTH CAROLINA 27603 TELEPHONE [phone]
ENGINEERING • PLANNING • ARCHITECTURE
November 19, 1987
Mr. Trevor Clements
Supervisor, Technical Support Unit
N.C. Division of Environmental Management
P.O. Box 27689
Raleigh, NC 27611
Re: Effluent Limitations
Benson, NC
Dear Trevor:
We appreciate receiving the effluent limitations for expanded flows
at Benson's wastewater treatment plant. We had all been concerned over
the possibility of not being able to discharge additional flow at the
current plant site. The planning process will proceed more positively
now knowing the plant can be expanded at the present site.
As we discussed by telephone, the Town had requested effluent limits
for two (2) additional sites: (1) The Neuse River and (2) Mingo Swamp.
If the discharge could not have been increased at the present plant site,
one (1) of these two (2) streams would become the discharge location.
Now that it appears the Neuse River will be declared nutrient
sensitive and phosphorus removal will likely be required, Mingo Swamp
takes on an added importance because this particular stream is tributary
to the Cape Fear River and phosphorus removal would not be required
(for the near term) -
Therefore, we request effluent limitations be developed for these
two (2) receiving streams. We have attached a map which shows the
appropriate location of the possible discharge(s). We have been re-
quested to submit an amendment to the Benson 201 Facilities Flan by
mid -January 1989. Therefore, we would appreciate receiving a deter-
mination of these values at your earliest available opportunity.
Thank you for your assistance in this matter.
cc: Town of Benson
Attachment
Sincerely,
L. E. WOOTEN AND COMPANY
By
rthur L. Kenne
SINCE 1936

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DIVISION OF ENVIRONMENTAL MANAGEMENT
October 27, 1987
MEMORANDUM
TO:
Dan Blaisdell
FROM:
Steve Zoufaly ')L7
THRU:
L
Trevor Clements
SUBJECT:
Town of Benson WWTP
(NPDES No. NC0020389)
The Town of Benson recently submitted wasteload allocation requests for
0.825 (current design flow), 1.0 and 1.274 MGD. The facility discharges to
Hannah Creek in Johnston County. The stream is classified as "C" with USGS
streamflow estimates of 7Q10s = 0.0 and 30Q2 = 0.075 cfs. Their present
permit limits are:
Summer
Winter
Q- 0.825
MGD
0.825
MGD
BOD., 5
mg/l
7
mg/l
NH_,-N 2
mg/1
2
mg/1
D.O. 6
mg/l
5
mg/l
TSS 30
mg/1
30
mg/1
Fecal Coliform :
i000/100 ml
1000/100
ml
pH : 6-9
SU
6-9
SU
Since the wastewater is discharged to a "low" flow stream, the facility
is governed by the Division's low flow stream procedures. As you may know,
an existing facility with no wasteflow changes receives its existing permit
limits. In this instance, however, winter BOD- and NH,-N limits are relaxed
upon renewal to 10 and 4 and the winter D.O. limit will change from 5 mg/1
to 6 mg/l. For the proposed wasteflow expansions of 1.0 and 1.274 MGD the
procedure states the summer/winter BOD, and NH,-N limits to be 5 and 2/10
and 4. The D.O., TSS, fecal coliform and pH limits will be 6 mg/l, 30 mg/l,
1000/100 ml and 6-9 SU respectively for both the summer and winter periods.
In addition to the above limits, chronic toxicity limits, instream
monitoring (both upstream and downstream), and effluent monitoring will be
required of the facility.
If we can be of further service, please contact either Trevor Clements
or myself.
SZ:gh
Attachment

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