NC0027006_Draft Permit_20031112

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Dear Mr. Rhode:
The Division made the following changes to your new permit on the bases indicated.
N. C. Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 [phone]
Ray Rhode
ExxonMobil Oil Corporation
2555 West Oak Street
Selma, North Carolina 27576
In 2001 the Division of Water Quality (the Division) revised permitting strategies and standard
operating procedures (2001 SOP) for this and for all bulk-storage petroleum facilities and terminals
in North Carolina. As part of your permit renewal, the Division has also conducted an EPA-required
Reasonable Potential Analysis on this facility's effluent data to determine the "reasonable potential"
for identified parameters to exceed North Carolina in-stream water quality standards and/or federal
criteria.
Nitrogen and phosphorus. The Division reviewed data reported during the previous permit
cycle, and concluded that there was sufficient data to support a decision to discontinue monitoring
these two nutrients.
ERA Method 624. As provided by the 2001 SOP, the Division reviewed data reported during the
previous permit cycle, and concluded that there was sufficient data to support a decision to
discontinue monitoring for these constituents.
BTEX constituents. No change from the previous permit is proposed for benzene and toluene.
Monthly monitoring of ethylbenzene has been added based on the provisions of the 2001 SOP.
Monitoring requirements for xylene have been changed from semi-annual to monthly, in
accordance with the 2001 SOP.
Subject: Draft NPDES Permit No. NC0027006
ExxonMobil Selma Terminal
2555 West Oak Street, Selma
Johnston County
NCDENR
Customer Service
1 800 623-7748
Michael F. Easley
Governor
William G. Ross, Jr. Secretary
North Carolina Department of Environment and Natural Resources
This letter transmits your draft NPDES individual discharge permit for the above referenced facility.
Please review this draft carefully to ensure thorough understanding of the information, conditions,
and requirements of dischargers to water supply waters contained therein.
A
MTBE. Monthly monitoring of MTBE has been added based on the 2001 SOP. After collecting
additional data, ExxonMobil may request a reduction in the MTBE monitoring frequency as
described in the permit text. Granting the request shall constitute a minor modification to the
NPDES permit.
Alan Klimek, P. E., Director
Division of Water Quality
November 12, 2003
Flow. Based on the 2001 SOP and the sporadic nature of the discharges from the facility, the
Division has changed the flow reporting requirement from monthly to episodic. In months with no
discharge, we still require submission of the Discharge Monitoring Report with the notation, "No
Discharge".
Respectfully,
Enclosure: NPDES Permit NC0027006
cc:
The previous permit requirements for TSS, oil & grease, EPA Method 625, and toxicity testing
remain unchanged.
Lead. The Division reviewed data reported during the previous permit cycle and concluded that
there was sufficient basis to remove the lead limit. The monthly monitoring requirement remains.
Following the 30-day public comment period, the Division will review all pertinent comments and
take appropriate action prior to issuing a final permit. If you have questions concerning the draft,
please call me at [phone], extension 584, or you may E-mail me at ken.pickle(g)ncmail.net.
Phenol. The Division has added a permit limit and monthly monitoring requirement for phenol
based on the data reported during the previous permit cycle and the 2001 SOP.
NPDES Unit: [Draft Permit; Fact Sheet]
Aquatic Toxicology Unit: [Draft Permit; Fact Sheet]
DEH: [Draft Permit; Fact Sheet]
Mr. Ray Rhode
Page 2
11/12/03
With this notification, the Division will solicit public comment on this draft permit by publishing a
notice in newspapers having circulation in the general Johnston County area, per EPA
requirements. Please provide your comments, if any, to DENR / DWQ / NPDES Unit no
later than 30 days after receiving this draft permit.
Ken Pickle
NPDES Unit
Permit NC0027006
DRAFT
PERMIT
ExxonMobil Oil Corporation
is hereby authorized to discharge wastewater from one outfall located at the
This permit shall become effective.2003.
This permit and authorization to discharge shall expire at midnight on March 31, 2008.
Signed this day 2003.
to receiving waters designated as an unnamed tributary of Mill Creek within the Neuse River Basin in
accordance with effluent limitations, monitoring requirements, and other conditions set forth in Parts I,
II, III and IV hereof.
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,
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
(NPDES)
ExxonMobil Selma Terminal
2555 West Oak Street
Selma, North Carolina
Johnston County
DRAFT
Alan W. Klimek, P. E.
Division of Water Quality
By Authority of the Environmental Management Commission
Permit NC0027006
DRAFT
SUPPLEMENT TO PERMIT COVER SHEET
ExxonMobil Oil Corporation
is hereby authorized:
1.
2.
3.
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked, and as of this issuance, any previously issued permit bearing this number is no longer effective.
Therefore, the exclusive authority to operate and discharge from this facility arises under the permit
conditions, requirements, terms, and provisions described herein.
to continue to operate the existing Water Pollution Control System consisting of:
• two oil/water separators,
• an aerated pond, and
• v-notch weir
located at the ExxonMobil Selma Terminal, 2555 West Oak Street, Selma, North Carolina;
to continue to discharge stormwater runoff from the aboveground storage tank containment area,
the yard, the truck loading rack, and the product pump area via Outfall 001;
to discharge at the locations specified on the attached map into an unnamed tributary to Mill
Creek in the Neuse River Basin, a WS-IV NSW class stream.
asoneK
ExxonMobil Oil Corporation
North
Sub-Basin: 03-04-02
Stream Class: WS-IV,NSW
Drainage Basin: Neuse River Basin
it
1
Facility
Location
not to scale
Outfall 001
(flows south)
35° 33’ 02” N
78° 18’ 44” W
NPDES Permit No. NC0027006
_____Johnston County______
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State GricVQuad: E 25 SE / Selma, NC
Permitted Flow. Episodic - not limited
Receiving Stream: UT of Mill Creek
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Permit NC0027006
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
45.0 mg/L
0.118 Ibs/day
1.
2.
3.
4.
Beginning on the effective date of the permit and lasting until expiration, the permittee is authorized to
discharge from Outfall 001. Such discharges shall be limited and monitored by the permittee as
specified below:
The permittee shall not discharge floating solids or foam visible in other than trace amounts.
The permittee shall not discharge tank solids, tank bottom water, or the tank rag layer.
The permittee shall not discharge tank (or pipe) contents following hydrostatic testing unless benzene
concentration is less than 1.19 gg/L and toluene concentration is less than 11 /ig/L.
EFFLUENT
CHARACTERISTICS Daily
Maximum
a.
b.
DRAFT
PARTI
c.
d.
I. 19 ug/L
II. 0 ug/L
Sample
Type
1
Grab
Grab
Grab
Grab
Grab
Grab
Grab
Grab
Grab
Grab
Grab
Flow1_____________
Total suspended solids
Oil and grease2______
Benzene___________
Toluene___________
Ethylbenzene_______
Xylene____________
Phenol_____________
MTBE3____________
Lead______________
EPA 625___________
Acute toxicity4
LIMITS
Monthly
Average
Footnotes:
Flow - During periods of no flow, the permittee shall submit a monthly Discharge Monitoring Report (DMR) indicating
“No discharge." Flow shall be monitored with each discharge event and may be monitored in one of four ways:
measure flow continuously;
Rational Method — calculate flow based on total rainfall per area including built-on area
draining to the outfall (This method shall not be used at sites with large runoff-collection
ponds);
estimate flow at 20-minute intervals during the entire discharge event; or
report flow based on discharge pump logs.
Oil and Grease - Where possible, the grab sample for oil and grease should be skimmed from the surface of a quiescent
(calm water) zone.
MTBE - See section A. (2.) Effluent Limitations and Monitoring Requirements Special Conditions - MTBE
Monitoring for other requirements relating to MTBE.
Acute Toxicity - Annual, Fathead Minnow, 24-hour. See section A. (3.) Effluent Limitations and Monitoring
Requirements Special Conditions - Acute Toxicity Monitoring
I\lONITdRI]
Jtflpdsurement
//Frequency j
/ Episodic /
/ Monthly/7
^-Monthly
Monthly
Monthly
Monthly
Monthly
Monthly
Monthly
____Monthly
2/Year
Annually
ING REQUIREMENTS
Sample
Location
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Effluent
Permit NC0027006
DRAFT
1.
2.
3.
A. (2.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS SPECIAL
CONDITIONS - MTBE MONITORING
. The Division anticipates that an MTBE regulatory criterion or Water Quality Standard will be
established during the coming permit cycle. For the next cycle of permit renewals, i.e., 2006, the
Division expects to apply this criterion or standard to MTBE data collected during this permit
cycle. Should the permittee’s MTBE data indicate discharge in excess of this criterion or Water
Quality Standard, an MTBE limit will be added to the permit monitoring requirements at
renewal. /
Monthly monitoring for MTBE (except as modified under 2.) is required for the duration of the
permit. See Part A. (1.).
If MTBE is detected during the test period, the permittee shall submit an MTBE Reduction Plan.
This plan may include site-specific Best Management Practices (BMPs) or engineering solutions.
A copy of this plan shall be submitted to:
After a one-year test period of monthly monitoring or after twelve (12) discharge events have
been sampled and analyzed, the permittee shall review MTBE data. If MTBE is not detected, the
facility may request the Division to reduce the MTBE monitoring frequency. Granting this
request shall constitute a minor modification to the NPDES permit.
North Carolina Division of Water Quality
Water Quality Section
Attn: NPDES Unit
1617 Mail Service Center
RaleighJSlC27699-1^17 ---------------------
For the protection of public health, oil terminals discharging to waters classified as water supplies
(“WS” waters) shall adhere to the following action plan:
Permit NC0027006
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, DWQ Form AT-1 (original) is to be sent
to the following address:
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.
Completed Aquatic Toxicity Test Forms shall be filed with the Environmental Sciences Branch no later
than 30 days after the end of the reporting period for which the report is made.
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 follow-up testing to be completed no later than the last day of the
month following the month of the initial monitoring.
Attention: North Carolina Division of Water Quality
Environmental Sciences Branch
1621 Mail Service Center
Raleigh, North Carolina 27699-1621
The permittee shall conduct annual toxicity tests using protocols defined as definitive in EPA Document
EPA/600/4-90/027 entitled “Methods for Measuring the Acute Toxicity of Effluents to Freshwater and
Marine Organisms.” The monitoring shall be performed as a Fathead Minnow (Pimephales promelas)
24-hour static test. Effluent samples for self-monitoring purposes must be obtained below all waste
treatment. The permittee will conduct one test annually, with the annual period beginning in January of
the calendar year of the effective date of the permit. 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.
DRAFT
A. (3.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS SPECIAL
CONDITIONS - ACUTE TOXICITY MONITORING (ANNUAL)
Should any test data from either these monitoring requirements 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.
Facility Information
Applicant/facility name ExxonMobil Oil Corporation /ExxonMobil Selma Terminal
Receiving stream and basin Regional office Raleigh
Stream classification and segment
001 Lat. 35° 33' 02” Long. 78° I8‘ 44"
Introduction
Facility Records Review
L
Summary Information ExxonMobil Selma Terminal - Water Pollution Control
System
ExxonMobil Oil Corporation (herein referred to as Exxon or the permittee) requires a National Pollutant
Discharge Elimination System (NPDES) permit to dispose treated wastewater to the surface waters of the
state. The permittee’s 5-year NPDES permit has expired and they have requested renewal from the Division
of Water Quality (the Division). This Fact Sheet summarizes background information and rationale used by
the Division’s NPDES Unit to determine permit limits and conditions.
Facility Description. Exxon operates the ExxonMobil Selma Terminal, a petroleum bulk-storage and fuel­
distribution center in Johnston County. Discharge from the facility is from a single outfall.
DENR / DWQ / NPDES Unit
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES Permit No. NC0027006
October 29, 2003
Discharge from Outfall 001 consists of two general flows: stormwater runoff from the AST containment
areas and yard, and stormwater runoff and spillage and leakage from the truck rack and product pump areas.
The Hows from the AST containment area and the yard drain to the Pinal oil/water separator, to an aerated
pond, through a broad-crested v-notch weir, and finally off the property as Discharge 001. The flows from
Fact Sheet
Renewal - NPDES Permit NC0027006
Page I
Applicant address
Facility address______
Permitted flow (MGD)
Type of waste
Facility/pcrmit status
County
2555 West Oak Street, Selma, North Carolina 27576
2555 West Oak Street, Selma. North Carolina 27576
Not limited__________________________________
Industrial runoff wastewater. SIC Code 5171
State grid /
USGS topo quad
Permit writer
Date:
Grade 1, minor / renewal___________
Johnston________________________
Receiving Water Information
303(d) listed?_______
Subbasin___________
Drainage area (sq. mi.)
Summer 7Q10 (cfs)
Winter 7Q10(cfs)
30Q2 (cfs)__________
Average flow (cfs)
fWC (%)
UT to Mill Creek, Neuse
River basin___________
WS-1V NSW, 27-40
Not listed
03-04-02
0.1______
0.0
0.0
0.0
0.0_____
100
E25SE/
Selma, NC
Ken Pickle
29Oct03
Compliance Review
Parameter Hits Allowable Comments / Action
Flow 43
Benzene 43 5 Yes
Xylene 43 7 46 ug/L 885 ug/L No
Phenol 43 9 281 ug/L 38 ug/L Yes
Oil & Grease 43 4 15 mg/L 30 mg/L No
Toluene 43 32 ug/l I I 0 ug/l.Yes6
Lead 43 3 7 3 ug/L 25 ug/l No
Verifying Existing Stream Conditions. This facility discharges to a “zero-flow” stream, an unnamed
tributary (UT) to Mill Creek, segment number 27-40, a class WS-IV NSW stream within the Neuse
River Basin. Mill Creek is not listed as an impaired waterbody in the 2002 Integrated 305(b) and
303(d) Report.
the truck rack and product pump areas are directed to a separate oil water separator, then to the final
oil/water separator (commingling with the flows from the AST containment and yard), then to the aerated
pond, across the v-notch weir, and finally leaving the property with the other flow as Discharge 001. The
discharge leaves the property in a ditch at the rear of the property which then enters an unnamed tributary
(UT) to Mill Creek.
The existing permit became effective September 1, 1999 (with an expiration date of March 31, 2003). On
August 22, 2002, the Division received Exxon’s permit renewal request.
Fact Sheet
Renewal - NPDES NC0027006
Page 2
Max.
Predicted
Waste Load Allocation (WLA). The Division reviewed the December 1992 WLA that developed
effluent limits and monitoring requirements based on an in-stream waste concentration (IWC) of 100%
(zero-flow stream). The Division judges these limits and monitoring requirements to be appropriate for
this renewal with the exception of the additions and deletions listed below (see PERMITTING APPROACH
SUMMARY).
RP*
y/n
Summary of Reasonable Potential Analysis (RPA). The Division conducted an EPA-mandated RPA
on Exxon’s reported data for benzene, lead, oil & grease, phenol, toluene, and xylene. Monitoring
parameters and the reasonable potential analysis (RPA) results are summarized in Table 1.
.369 MGD
measured
5 ug/L
Max. reported value used lor RPA
________Episodic monitoring._______
Retain permit limit per RPA and 2001
_____SOP. Monthly monitoring.
Increase to monthly monitoring per
____________2001 SOP.
Assign permit limit per RPA and 2001
_____SOP. Month!) monitoring.
Retain monthly monitoring per 2001
SOP._______
Retain permit limit per RPA and 2001
SOP_____________________________
Drop limit based on RPA. Retain
No limit
—
1.19 ug/L
Discharge Monitoring Reports (DMR) - Effluent Data Review. DMRs were reviewed from
September 1999 through September 2003. Discharges generally occurred on a regular basis, with
occasional months with no discharge related to drought conditions. Those monthly DMRs were
submitted with the notation “no flow.” The permittee reported a maximum discharge of 0.369 MGD in
August 2000. This maximum flow was used for the reasonable potential calculations (see below).
Table 1. Exxon Selma Terminal, Outfall 001 - DMR Review Summary, RPA Results, and
SOP Limitations
Samples
37 45 nig/L
5/5 0/0 XD/XD
Total phosphorus 43 5
Total nitrogen 3943
Notices of Violation (NOVs).No NOVs were issued to this facility during this permit cycle.
Permitting Strategy
Renewal
Facility Inspections. The Raleigh Regional Office (RRO) inspected this facility on October 9, 2002.
Significant findings for the purposes of this permit renewal included the following:
RRO noted that a phenol limit as a concentration limit rather than a mass limit is preferable. A mass
limit is deemed appropriate since the flow is variable and no permitted flow limit is established.
Furthermore, previous oil terminal permits have included mass limits on phenol, and the Division will
continue this precedent.
Whole Effluent Toxicity (WET) Test. The facility has passed an annual acute toxicity test five
times during the permit period. One year was skipped (2001). but two tests were conducted in another
year (2003).
Revised Standard Operating Procedures (SOP). The Division of Water Quality has revised the
permitting strategies and the SOP for this and all oil terminals in the state. A new document has been
generated by the NPDES Unit entitled, “Permit Requirements for Discharges from Oil and Petroleum
Storage Facilities 2001 Permitting Strategy” (based on a 1996 SOP). This document, hereafter referred
to as the 2001 SOP. addresses issues and delineates monitoring frequencies and permit limits for
contaminants commonly found at these facilities.
= “Reasonable Potential” to exceed in-stream Water Quality Standard.
= milligrams per liter
= micrograms per liter
= not detected
Fact Sheet
NPDES NC0027006
Page 3
TSS________
TOX (1999-
2003)
EP/\ 624/625
43
5
Ethylbenzene
MTBE
*RP
mg/L
pg/L
ND
Summary of Compliance Under 2001 SOP. Under the 2001 SOP. flow monitoring will be
changed from “monthly” to “episodic” (2001 SOP Part I.A.). This facility’s effluent shall be analyzed
monthly (unless there is no discharge during the month) for TSS (I.C.), oil and grease (I.D.), phenol
(III.A.), BTEX (I E., I1I.B ), and MTBE (I.I., 1I1.C.). Lead will be monitored monthly. This facility's
effluents shall be analyzed twice per year by EPA Method 625 (I.F.). This facility’s effluent shall be
tested annually for acute toxicity (I.B.).
Footnotes to the Effluent Limits and Monitoring Requirements page shall reflect no direct discharge of
tanks solids, lank bottom water, or the tank rag layer. Footnotes will also stipulate no direct discharge
monthly monitoring based on 3 hits.____
Retain permit limit based on 2001 SOP.
All passed at >100%. Retain per 2001 W
______________SOP._______________ 1
Retain 625 per 2001 SOP. Drop 624
based on no delected constituents. Note
that even though Exxon submitted only
half of the ten (semi-annually for five
years) required analyses, the database is
____________sufficient._____________
Remove from permit based on analysis
___________of database.____________
Remove from permit based on analysis
of database.________________________
Add monthly monitoring per 2001 SOP.
Add monthly monitoring per 2001 SOP.
Flow calculations:
of hydrostatic test water if benzene and/or toluene concentrations exceed their respective water quality
standard (I.G. and l.H).
Given: Flow (30Q2) Neuse River
Flow (30Q2) Buffalo Creek
Estimated 30Q2 at raw water intake
f act Sheet
Renewal - NPDES NCOO27OO6
Page 4
Neuse River Basin Nutrient Limitations. Nitrogen. The Environmental Management Commission
has established nutrient reduction goals and strategies for the Neuse River basin (I5A NCAC 2B
.O232ff). Section 2B .0234(5)(i) provides that dischargers with permitted flows less than 0.5 MGD
shall be assigned collectively an annual discharge allocation of 138,000 pounds. For the permit period
from September 1999 through September 2003, Exxon has reported only two annual nitrogen totals of
185.2#N/yr (2001) and 29.13#N/yr (2002). These values represent an annual contribution of less than
0.15% and less than 0.02%, respectively, of the annual allocation for this class of permittees
(approximately 120 permittees). Data values this low support the NPDES Unit’s internal designation
of Exxon’s discharge as a non-nutrient bearing wastestream. Further, the database is sufficient to
support the elimination of the nitrogen monitoring and reporting requirement in the current permit.
Neither the Division nor the permittee has identified a nitrogen source on this site. No nitrogen limits,
monitoring, or reporting are proposed for the new pennit.
219 cfs
0.18 cfs
218.8 cfs
(USGS Gauging Station)
(USGS data)
(Neuse - Buffalo Ck flow)
Phenol - Monitoring and Limits Calculations. When combined with chlorine, phenol can cause
taste and odor (organoleptic) problems in drinking water, and can also result in the tainting of fish
tissues. Therefore, in accordance with the 2001 SOP. all dischargers to state water supply (WS) waters
shall conduct monthly effluent monitoring for phenol. Moreover, if analytical results suggest
“reasonable potential,” a phenol limit shall be included in the permit.
A phenol limit magnitude depends on dilution. Dilution has been calculated at the Smithfield water
plant intake where chlorine is introduced. The Division used 1 j-tg/L (the aesthetic limit for phenol) at
the raw water intake to calculate a waste load allocation in pounds per day (Ibs./day). Finally, the
waste load allocation was distributed equally among phenol dischargers as a permit limit, only as each
facility’s data set showed reasonable potential to exceed the water quality stream standard.
Currently ten bulk storage facilities discharge to unnamed tributaries to Mill Creek. The Division used
published 30Q2 flows from an EPA stream gauge located on the Neuse River at the US Highway 70
bridge in Smithfield. The 30Q2 flow, not the 7Q10. was deemed appropriate because of the aesthetic
standard for phenol.
Phosphorus. Section 2B .0234(6) establishes a quarterly average phosphorus discharge limit of 2.0
mg/L for two categories of dischargers in the Neuse basin, not including Exxon. However, applying
the 2.0 mg/L as guidance as to what level may be significant in supporting the Neuse River basin
nutrient reduction goals and strategies is helpful in evaluating the Exxon permit renewal. Exxon
averaged less than 0.17 mg/L for the preceding permit period, and only one of the 43 reported values
exceeded the 2.0 mg/L quarterly average value applied to other dischargers. Data values this low
support the NPDES Unit’s internal designation of Exxon’s discharge as a non-nutrient bearing
wastestream. Further, the database is sufficient to support the elimination of the phosphorus
monitoring and reporting requirement in the current permit. Neither the Division nor the permittee has
identified a phosphorus source on this site. No phosphorus limits, monitoring, or reporting are
proposed for the new permit.
IM7P
Phenol waste load calculation:
1.177 lbs./day distributed among ten dischargers
Phenol allocation 0.118 Ibs./day per discharger site
Phenol limit
Phenol limit 0.118 Ibs./day
Permitting Approach Summary
1.177 Ibs./day
10 dischargers
Based on a review of the monitoring data from the last permit cycle and per the DWQ/NPDES Unit’s
2001 SOP the following permit renewal decisions are proposed:
0.118 Ibs./day per discharger site
1 outfall at Exxon
For Outfall 001:
• Add a phenol limit based on the RPA and the 2001 SOP. Monthly monitoring.
• Add an ethylbenzene monthly monitoring requirement based on the 2001 SOP. No permit
limit.
• Add an MTBE monthly monitoring requirement based on the 2001 SOP. No permit limit.
• Increase the xylene monitoring requirement from semi-annual to monthly based on the 2001
SOP. No permit limit.
• Change the flow reporting requirement to episodic, rather than monthly, based on the 2001
SOP.
• Drop the lead limit. Retain monthly monitoring based on three hits during the permit period.
• Drop the nitrogen monitoring requirement based on data analysis.
• Drop the phosphorus monitoring requirement based on data analysis.
• Drop the 624 semi-annual testing requirement based on the 2001 SOP.
• Retain the 625 semi-annual testing requirement per the 2001 SOP. No permit limits.
• Retain the toluene limit based on the RPA.
• Retain the oil & grease limit based on the 2001 SOP.
• Retain the TSS limit based on the 2001 SOP
• Retain the benzene limit based on the RPA.
• Retain the annual toxicib testing requirement based on the 2001 SOP.
218.8 cfs x (0.001 mg/L) x 8.34
1.55
Phenol allocation
Fact Sheet
Renewal - NPDES NC0027006
Page 5
Based on the RPA and 2001 SOP, the Division has assigned a phenol limit of 0.118 lbs./day as a
Monthly Average to Outfall 001 at the ExxonMobil Selma Terminal. A monthly average limit is
consistent with the use of the 30Q2 flow for organoleptic parameters. A footnote will be added to the
permit allowing the permittee to collect additional phenol data (minimum 12 data points) and petition
for a new RPA.
Proposed Schedule of Issuance
NPDES Unit Contact
Name: Date:
Renewal
Draft Permit to Public Notice:
Permit Scheduled to Issue:
November 12, 2003.
December 27, 2003
If you have questions regarding any of the above information or on the attached permit, please contact
Ken Pickle at [phone] ext. 584.
Fact Sheet
NPDES NC0027006
Page 6
Regional Office Comments
DATE: Name:
Date: Regional Supervisor:
Date: NPDES Supervisor:
Fact Sheet
Renewal - NPDES NC0027006
Page 7