NC0031046_CORRESPONDENCE_19900212

NPDES DOCUMENT SCANNINK COVER SHEET
NPDES Permit:
NC0031046
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
#Correspondence
Speculative Limits
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
February 12, 1990
This document is printed on reuse paper - iQPnore any
content oa the reverse side

State of North Carolina
Department of Environment, Health and Natural Resources
Division of Environmental Management
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor George T. Everett, Ph. D.
William W. Cobey, Jr., Secretary Director
February 12, 1990
Mr. David V. Pearson
Colonial Pipeline Company
PO Box 18555 1d-
Atlanta, Georgia 30326 COY W
3 1990
TECHNI t suppoRT 6RNNCH
Dear Mr. Pearson:
�i
Subject: NPDES Permit No. NCO031046
Colonial Pipeline Company
Guilford County
The Division�bf Environmental Management has reviewed your letter dated January 11,
1990 and, respectively offers the following comments. As far as flow monitoring is concerned, the
Division proposes to replace the weekly flow measurement frequency with the requirement, "Flow
shall be monitored from each outfall during every rainfall event that results in a discharge."
Furthermore, the statement on the effluent limitations and monitoring requirements page
concerning calculating flow using the drainage area and rainfall data obtained from rainfall gauges
has been deleted from the subject permit. The sample type for flow shall be instantaneous and the
sample location will be at the effluent.
The twice per month effluent measurement frequency for pH, oil and grease, turbidity, and
phenols will remain as a requirement of the subject permit. As far as laboratory turn -around time is
concerned, your company has thirty days following the end of a month to submit the monitoring
data without it being considered late. Many laboratories have a turn -around time of less than three
weeks, and some even offer overnight service.
In lieu of the settleable solids limit in the subject permit, the Division proposes a monthly
average total suspended solids limit of 30.0 mg/l and a daily maximum of 60.0 mg/1. The
measurement frequency for total suspended solids will also be twice per month.
In lieu of the acute toxicity test in the subject permit, the Division proposes a 24 hour
fathead minnow monitoring requirement. If Colonial Pipeline Company would prefer that the
acute toxicity have a limit, as opposed to a monitoring requirement only, the Division will limit this
effluent characteristic.
Pollution Prevention Pays
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer

The statement concerning the discharge period which reads "The facility shall record the
appropriate time the discharge begins and stops during a discharge period" is in error. This
statement has been corrected in the subject permit as "The facility shall record the approximate time
the discharge begins and stops during a discharge period." This discharge information is very
important in that it allows the total volume of effluent to be estimated for a rainfall event, as well
as, the approximate loads associated with that event. Approximate times of discharge should not
be difficult to estimate with a combination of visual observations and a familiarity of the retention
ponds and their hydrology.
Finally, the phenols limit of 0.001 lbs/day as a daily maximum site allowable effluent limit
from all six discharges is necessary to adequately protect the downstream water supply. However,
if your company objects to phenols limits based on loading rates, the Division will consider
assigning a concentration limit instead. However, due to the variability of flow rates and discharge
characteristics and the proximity of numerous other interacting discharges, the limit for each outfall
would be a daily maximum of 1.0 ug/l.
Please submit a response to the Division of Environmental Management concerning the
subject permit by March 5, 1990. If you have any questions, please contact me at [phone].
Sincerely,
�
e.-Dale Overca�sh, P.E.
Supervisor NPDES Permits
cc: Winston-Salem Regional Office
Technical Support Branch]
Pemut File

i�
NORTH CAROLINA DEPARTMENT OF ENVIRONMENT, HEALTH,
AND NATURAL RESOURCES
Division of Environmental Management.
February 7, 1990 5� gg1/
ED
MEMORANDUM FEB 0 9 1990
TO: Dale Overcash, Supervisor TECiu;iCAL SUPPORT BRANCH
NPDES Permits Group
THROUGH: M. Steven Mauney, Supervisor
Water Quality, WSRO 4
"-iE- ­A� +
FROM: Arthur R. Hag9trom, Environmental Engineer
Water Quality, WSRO
SUBJECT: WSRO Response to Colonial Pipeline Company's letter
to M. Dale Overcash Dated January 11, 1990, Regarding
Their Comments to the Draft NPDES Permit No. NCO031046
Currently Under Review, Guilford County
Our comments are keyed to the Colonial letter and are as
follows:
1. Flow Monitoring.
Flow should be measured whenever a discharge occurs without
regard to time of day or night. I discussed with Colonial the
use of several on -site rain gauges rather than off -site old rain
data from the area meteorologist to determine estimated flows
using surface drainage areas for each discharge. If they need to
staff their facility to allow for 24 hour coverage, it doesn't
seem out of order. Upstream and downstream flow measurement with
recording is what this major oil transporter should have on the
stream through the site.
2. Measurement Frequency.
We do not see any good reason to reduce sampling by this
facility. Since technical services and the Division of Health
Services regards phenols as important no changes should be done
with phenol testing frequencies. Local labs have responded by
turning out phenol tests in less than one week.
3. Settleable Solids.
This parameter and the units seems to be used in numerous
areas in many DEM Permits. No change seems warranted.

Mr. Dale Overcash
February 7, 1990
Page 2 of 2
4. BTX and Acute Toxicity.
It is not the State's fault that they put in six (6)
separate discharges around the perimeter of two lakes. They
might be able to combine the discharges. Since the discharge
areas serve different products (various gasoline products and
oils), single samples of each discharge would not seem to be able
to identify problems. It may be that they could use samples from
their downstream lakes discharge to test the effluent from all
tank farms plus their own. If problems are found they could then
go back to their six (6) discharges and determine compliance.
5. Discharge Period.
They should report each discharge event during each 24 hour
day (midnight to midnight). If it rains over -night, then
discharges occur on two days. They may use on -site rain gauges
to help determine flows. We would prefer six (6) flow meters or
one flow facility on the upstream and one on the downstream on
the stream through the property.
6. Effluent Limitation for Phenols.
The reduction of phenol limits for this facility from .0012
lbs/day to .0009 lbs/day for the largest facility at the
Greensboro Tank Farm does seem to be unfortunate. Since the
terminal discharges only several times per month, they may need
to control their discharges over several days to enable them to
meet the Permit limits for phenols.
MSM/ARH/ahl
CC: Technical Support Branch
WSRO
Central Files

DIVISION OF ENVIRONMENTAL MANAGEMENT
February 5, 1990
TO: Dale Overcash
THRU: Ruth Swanek 2CS •'f�
Trevor Clement s
FROM: Mike Scoville ►�Dj
SUBJECT: Comments on Draft permit for Colonial Oil Company
(NPDES No. NC0031046, Guilford County)
This memo is in response to the requested changes in the subject facil-
ity's NPDES Draft permit. Recommendations.of Technical Support addressing
the Company's concerns are as follows:
Flow should be measured weekly by an instantaneous sample as indicated
on the limitation page of the permit. The body of the permit apparently was
inadvertently overlooked when this requirement was changed at permit
renewal. It has been determined that the calculated sample type of flow
monitoring is unacceptable from a compliance standpoint. The instantaneous
flow samples provide a flow rate that is coincident with the effluent con-
centrations determined by effluent monitoring. Calculation methods of flow
estimation do not provide this, nor do they allow accurate estimation of
loading rates per discharge event. The calculated sample type should not be
in the permit at all, only an instantaneous flow monitoring requirement.
Measurement Frecuencv
Twice -per -month effluent monitoring of pH, oil & grease, settleable sol-
ids, turbidity, and phenols are required of all discharges of this size and
nature. The monitoring frequency should not be changed. As far as labora-
tory turn -around time, Colonial has 30 days following the end of a month to
submit the monitoring data without being considered late. This is adequate
time to submit 2/month sampling data. Many laboratories have a much quicker
turn -around time than three weeks, some even offer overnight service. Also,
there are many facilities that meet their daily monitoring requirements
without schedule difficulties.
It is acceptable to Technical Support for a TSS limit of 30 mg/l monthly
average (60 mg/1 daily maximum) be added to the permit in lieu of the set-
tleable solids limit.

TX and Acute Toxicitv Testin
Although the amount of sampling required of Colonial in the first year
of the permit may seem excessive, data from one discharge are not represent-
ative of five other different outfalls. Division policy is to require moni-
toring and toxicity testing on five discrete discharge event in the first
year and then annually after that. While it is unfortunate that Colonial
has six separate outfalls, these requirements should apply to each outfall.
The acute toxicity test should be changed to the 24 hour/fathead min-
now/LC50 (see attached). The test requires the determination of the LC50 of
an effluent; there is no pass/fail criteria because it is only a monitoring
requirement and not a limit. If Colonial would prefer, a specific LC50
could be assigned as a limit to give them an indication of whether their
wastewater is treated to a satisfactory degree for toxicity compliance.
Discharge Period
The limitation page contains a typographical error with respect to the
flow footnote. The word "appropriate" should be replaced with "approxi-
mate". This information generates important data necessary to the NPDES
monitoring requirements. The general premise is to have the facility mea-
sure an instantaneous flow during the discharge and coincident with the
effluent monitoring, and then approximate the length of the discharge event.
This is very valuable information in that it allows the total volume of
effluent to be estimated for an event, as well as the approximate loads
associated with that event. Approximate times of discharge should not be
difficult to estimate with a combination of visual observations and a famil-
iarity of the retention ponds and their hydrology.
Effluent Limitation for Phenols
Phenols is limited because the receiving waters are classified as WSIII
due to the downstream location of High Point's water supply. Phenols can
cause taste and odor problems in a water supply and are therefore limited to
1.0 ug/l by NCAC .0211(e)(3)(B). To account for runoff dilution that occurs
between the water supply and the discharges from the oil storage facilities,
the 7Q10 was determined just above High Point Lake and the total allowable
phenols load that could occur at that point under those flow conditions
without violating the standard was calculated. Concentration based limits
could not be divided among the oil facilities because the variability of
flows, makes the mass balance approach inappropriate. The lbs/day limit
allows the effluent phenols concentration to vary according to the amount of
discharge. Attached is a summary of the Division's management approach and
it's application to East Fork Deep River for you to forward to Colonial.
The current draft permit is over -allocating phenols to Colonial Pipe-
line. Colonial is allowed a total phenols load of 0.001 lb/day; the draft
permit includes a 0.001 lb/day limit for each of their six'outfalls. The
total limit should be divided among the separate outfalls if the downstream
water supply is to be adequately protected. Permit limits of 0.001 lb/day
per outfall exceeds the allowable phenols allocated to the East Fork Deep
River and facilitates violations of the stream standard.
If Colonial objects to phenols limitations based on loading rates, it is
acceptable that a concentration limit be assigned instead. However, due to

the variability of flow rates and discharge characteristics, and the proxim-
ity of numerous other interacting discharges, the limit for each outfall
would be a daily maximum value of 1.0 ug/l. This option should be made
available to the facility.
If you have any questions or comments, please feel free to contact me.
Also, please forward a copy of your response to Colonial to Technical Sup-
port for our records.

11/89
Facility Name Co(nnra�h, PC �ifu Com OLAPermit# 9(,00310°/6
ACUTE TOXICITY TESTING REQUIREMENT
Fathead Minnow 24 hr - Monitoring (Annual) for Episodic Events
The petmittee shall conduct FIVE acute toxicity tests using protocols defined as definitive in
E.P.A. Document 600/4-85/013 entitled "The Acute Toxicity of Effluents to Freshwater and
Marine Organisms". The monitoring shall be performed as a Fathead Minnow (Pinrephales
promelas) 24 hour static test, using effluent collected as a single grab sample. Effluent samples
for self -monitoring purposes mast be obtained below all waste treatment. Sampling and
subsequent testing will occur during the first five discrete discharge events after the effective date
of this permit. After monitoring of the first five toxicity tests, the permittee will conduct one test
annually, with the annual period beginning in January of the next calendar year. The annual test
requirement must be performed and reported by June 30. If no discharge occurs by June 30,
notification will be made to the Division by this date. Toxicity testing will be performed on the
next discharge event for the annual test requirement.
The parameter code for this test is TAE6C. All toxicity testing results required as part of this
permit condition will be entered on the Effluent Discharge Form (MR-1) for the month in which it
was performed, using the appropriate parameter code. Additionally, DEM Form AT-1 (original) is
to be sent to the following address:
Attention: Environmental Sciences 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 either these monitoring requirements 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.
Failure to submit suitable test results will constitute noncompliance with monitoring requirements.
7Q10 0.0 cfs
Permitted Flow MGD
1WC%
Basin & Sub -Basin 010400
Receiving Stream ur t. F o;;irk I Rluet-
County Gu l�ec�
Recommended by:
Date I 3 +o
**Acute Toxicity(Fathead Minnow 24 hr) Monitoring, EPISODIC, See Part 3 , Condition _GL-.

• IINDA IOWFNS 3990 NfAU URFE ROAD NI nR AN1A, GA 30370IlOB I404) 70 LInJ0
V.A. YARBOROUGH T.W. CERVINO
Dneclor Eng;eonp January 11, 1990 Supem.5orEnvironmentat
Mr. M. Dale Overcash, Supervisor
Department of Environment, Health and Natural Resources
Division of Environmental Management JAN 16 j990
NPDES Permits Group
P. 0. Box 27687 PERP40 &�71 IP•!FFRmc
Raleigh, North Carolina 27611-7687
Re: NPDES Permit No. NCO031046
Greensboro Junction Tank Farm
Guilford County
Dear Mr. Overcash:
Colonial Pipeline Company has received the new draft NPDES permit for the above
referenced facility. Colonial would like to take this opportunity to address
a few aspects of the permit before the issuance of the final permit. The topics
for discussion are as follows:
Flow Monitorin
The body of the permit stipulates that the reportable flow may be calculated as
in the past. The limitation page, however, states that the flow shall be
1 measured weekly by an instantaneous sample. These two statements are
contradictory. The limitation page should be changed to a monthly measurement
frequency and calculated sample type to avoid misinterpretation. The monthly
frequency should be maintained to be compatible with the monthly sampling and
reporting.
Measurement Frequency
The parameters of.pH, Oil & Grease, Settleable Solids, Turbidity, and Phenols
are the new parameters to be monitored on a twice per month frequency. Of these
parameters, a history of monitoring data has been established for pH, oil &
grease, and phenols. Records show that over the last three years, out of 352
1 total analyses on the three parameters,Colonial has achieved a 96% compliance
record. Therefore, Colonial does not believe an increased monitoring frequency
is warranted. As for the other parameters not having an established database,
Colonial proposes to monitor monthly, and if a problem is discovered, review and
adjust the frequency accordingly. Another problem associated with a twice per
month monitoring frequency is the laboratory turn -around time. Laboratories
typically are only able to guarantee, at best, a three week turn -around.
Reporting deadlines would be difficult to uphold on that schedule.

Colonial Pipeline Company
M. Dale Overcash
Department of Environment, Health and Natural Resources
Page 2
.;anuary 11, 1990
Settleable Solids
An analytical method specifically for settleable solids does not exist. The
closest method would be Std. Method No. 209F. This method, however, is usually
used for analysis on biomass from a treatment plant aeration basin. It is a
gross approximation where typical volumetric quantities are in the order of 250
�\ ml/l. The minimum detection limit is also only 1 ml/l which is greater than the
1 limits stipulated in the permit. This parameter, therefore, does not apply.
A more representative analysis would be "total suspended solids" referenced as
EPA Method No. 160.2. This method is based on a weight percentage, is approved
for NPDES permits, and has a minimum detection limit of 4 mg/l. A practical
permit limitation is 50 mg/l.
BTX and Acute Toxicity Testin
Colonial contends that the amount of testing required in the first year of the
new permit for BTX and Acute Toxicity is excessive. The draft permit
H1 requirements of analyzing the first five discrete discharges on each of the six
discharge points would incur costs of over $9000.00 in the first year for these
two parameters. Representative samples can just as effectively be obtained by
one of the following proposed approaches:
1. monitor one representative location for the five background events
and then resume the annual frequency on all six, or
2. simply establish annual A.T. testing at the six locations, if a
location fails, then require additional testing, but only at the failed
locations.
The permit also does not address a pass/fail criteria for the acute toxicity
�\ testing. What conclusions will be drawn from the submitted results, how will
1 these conclusions be formulated, and what subsequent action will take place if
a test is considered a failure?
Discharge Period
On the limitation page, a statement was made that the facility is required to;
record the appropriate time the discharge begins and stops during a
o discharge period." This requirement would:
1. be extremely difficult to monitor, because of the variability in storm
durations and existing ground conditions at the time of the rainfall,
2. cause unnecessary "chasing around" continually checking to see if a
discharge had started or stopped,
3. be overlooked if a discharge either started or stopped at times other
than normal working hours, and
4. does not generate any important data necessary to this monitoring
program developed to comply with the NPDES regulations.

Colonial Pipeline Company
M. Dale Overcash
Department of Environment, Health and Natural Resources
Page 3
January 11, 1990
For these reasons, Colonial believes this requirement should be eliminated from
the final permit.
Effluent Limitation for Phenols
Concentration rather than loading limitations are normally used in NPDES
programs. CoTonialigould•rike•the reason for the pounds per day loading rate
limit, raft,;,6xplanation .of,^wherether'A 009 --lbs/day, total,Jimit originated', and
the rationale for the equal division of that total limit among nine dischargers
without regard to facility size or flowrates. Colonial would like to at least
continue with the existing limits of 0.0024 lbs/day daily maximum and 0.0012
lbs/day daily average.
Colonial would appreciate careful consideration of the above suggested changes
to the draft permit. The proposed revisions reflect reasonable compromises
while maintaining the intent of the NPDES program; which is to establish
environmentally sound control of industrial discharges. Explanations and answers
for the other outlined questions would also be appreciated to help understand
certain aspects and intentions of this draft NPDES permit.
Yours v ry truly,
D. V. Pearson
Engineer
cc: T. W. Cervino
W. C. Edwards
J. E. Marder
H. R. Melendy