NCS000574_Draft Permit Fact Sheet To Notice_20141014

DENR/DEMLR
FACT SHEET FOR NPDES STORMWATER PERMIT DEVELOPMENT
NPDES No. NCS000574
Facility Information
Applicant/Facility Name:
Duke Energy Progress, Inc., Cape Fear Steam Electric Plant
Applicant Address:
500 CP&L Road, Moncure, North Carolina 27559
Facility Address:
500 CP&L Road, Moncure, North Carolina 27559
Permitted Flow:
N/A (Stormwater Discharges Only)
Industrial Activities:
Primary SIC Code: 4911- Electric Services
Permit Status:
New NPDES Stormwater Permit
County:
Chatham Count
Miscellaneous
Receiving Stream:
Shaddox Creek
Regional Office:
Raleigh Regional
Office
Stream Classification:
WS-IV
State Grid / USGS Quad:
E22NE Merry Oakes
303(d) Listed?
No
Permit Writer:
M. Randall
Subbasin:
03-06-07
Date:
October 14, 2014
Facility Location: Lat. 35135' 15" N Long. 79° 02' 39" W
BACKGROUND
The Cape Fear Steam Electric Plant is a retired steam cycle electric generating plant that
formerly operated two coal-fired units, two heat recovery boilers and four Internal Combustion (IC)
Turbines in Chatham County. The site was retired in 2011 and is currently being demolished.
STORMWATER OUTFALLS AND DRAINAGE AREA DESCRIPTIONS
Outfall 007, Outfall 001 and Outfall 005
All wastewaters formerly generated by the site historically discharged to an effluent channel prior
to the combined outfall (Outfall 007). Outfall 007 contains all waste stream flows including the
West Ash Pond Discharge (Outfall 001) and the East pond Discharge (Outfall 005). At this time,
Outfall 007, Outfall 001, and Outfall 005 are regulated as a wastewater discharge.
Outfall SW-1 and Outfall SW-8 (also identified as Outfall 008)
Outfall SW-1 and Outfall SW-8 (also identified as Outfall 008) are legacy riser structures from
inactive ponds. Discharges of stormwater from these two outfalls are rare and NCDENR has
concurred with the estimation that it would take greater than the 25-year, 24-hour storm event for
there to be a discharge form either of these outfalls. Outfall SW-1 discharges into the Cape Fear
River. Outfall SW-8 discharges into the Shaddox Creek which flows into the Haw River just above
the confluence with the Deep River which forms the Cape Fear River.
Fact She-

The heavily vegetated area basically functions as a large dry detention pond, and water levels rarely
build up to the CMP riser pipe that leads to the discharge outlet pipe. The draft permit proposes
monitoring for this outfall only if a discharge results from a storm event less than the 25-year, 24-
hour storm (approximately 5.7" inches in this area of NC, based on NOAA Precipitation Frequency
Estimates). In the industrial stormwater permitting program, NCDEMLR considers holding ponds
that do not discharge in response to smaller storms as equivalent to a non -discharging system (on
the basis that more conservative design specifications for engineered non -discharge systems use
that same design storm criterion). The proposed permit condition is consistent with that
interpretation.
The stormwater outfall discharge from the Abandoned Ash Pond (1953) identified as SW-1 and
Abandoned Ash Pond (1963/1970) identified as Outfall SW-8 (also identified as SW-008) are not
considered a potential point source discharge to surface waters, as observed by DEMLR staff during
a site visit on November 12, 2014. At this time, SW001 and SWO08 are not a regulated point
source discharge.
Outfall SW-2
Stormwater collected along the railroad track between the plant entrance road and the plant site
combines with drainage of and open field which is directed via outfall SW-2 into Shaddox Creek that
flows into the Haw River just above the confluence with the De iver.
DENR anticipates that the demolition and/or closure of the site s ash ponds mays be underway,
and that the activity may be begun and completed within the term of the stormwater permit. We
would expect that some aspects of the ash pond closure activity may present the potential for
stormwater pollution, for example, activities such as transport of ash by rail and/or along on -site
haul roads. At this time, Outfall SW-2 will be regulated as a stormwater discharge from
an industrial activ'
Outfall SW-3
Stormwater collected along the roadside swell beside the plant entrance road is directed via Outfall
SW-3 toward drainages that go to Shaddox Creek. Historically this location was selected to capture
potential impacts from an ash sluice line that crossed under the entrance road. Ash is no longer
sluiced and the line has been disconnected.
DENR anticipates that the demolition and/or closure of the site's ash ponds may soon be underway,
and that the activity may be begun and completed within the term of the stormwater permit. We
would expect that some aspects of the ash pond closure activity may present the potential for
stormwater pollution, for example, activities such as transport of ash by rail and/or along on -site
haul roads. At this time, Outfall SW-2 will be regulated as a stormwater discharge from an
industrial activity.
0utfa11 SW-5
Stormwater collected in an open field along the entrance is directed via outfall SW-5 into Shaddox
Creek that flows into the Haw River just above the confluence with the Deep River. Outfall SW-5 is
not from an industrial activity.
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NPDES Stormwater Permit NCS000549
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Outfall from the Coal Pile
Stormwater collected in the coal pile area is discharged into into Shaddox Creek that flows into the
Haw River just above the confluence with the Deep River. Duke Energy removed the coal and coal
residual and restored the area.
WHY THIS FACILITY IS SUBJECT TO A PERMIT
Federal NPDES regulations define stormwater discharge associated with industrial activity in
40 CFR §122.26 (b)(14) as "the discharge from any conveyance that is used for collecting and
conveying storm water and that is directly related to manufacturing, processing or raw materials
storage areas at an industrial plant. The term does not include discharges from facilities or
activities excluded from the NPDES program under this part 122. For the categories of industries
identified in this section, the term includes, but is not limited to, storm water [sic] discharges from
industrial plant yards; immediate access roads and rail lines used or traveled by carriers of raw
materials, manufactured products, waste material, or by-products used or created by the facility;
material handling sites; refuse sites; sites used for the application or disposal of process waste
waters (as defined at part 401 of this chapter); sites used for the storage and maintenance of
material handling equipment; sites used for residual treatment, storage, or disposal; shipping and
receiving areas; manufacturing buildings; storage areas (including tank farms) for raw materials,
and intermediate and final products; and areas where industrial activity has taken place in the
past and significant materials remain and are exposed to storm water. For the purposes of
this paragraph, material handling activities include storage, loading and unloading, transportation,
or conveyance of any raw material, intermediate product, final product, by-product or waste
product. The term excludes areas located on plant lands separate from the plant's industrial
activities, such as office buildings and accompanying parking lots as long as the drainage from the
excluded areas is not mixed with storm water [sic] drained from the above described areas."
Although electricity generation at the Cape Fear Steam Electric Plant has ceased, coal ash and other
materials are still present at the site.
PROPOSED MONITORING FOR STORMWATER DISCHARGES
The Division considered potential pollutants fro 7tand present industrial activities (coal-fired
electric generation, plant decommissioning, and future ash removal). Unlike most stormwater
permits in its program, the Division is proposing a permit structure with outfall-specific monitoring
for discharges. Parameters are based on potential pollutants in the drainage area, sampling results,
and in some cases, dependent upon future activities (e.g., ash removal through the drainage area).
Below is a table of the proposed monitoring for each outfall at the Cape Fear Steam Electric Plant
site.
Fact Sheet
NPDES Stormwater Permit NCS000549
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Stormwater Discharge Outfall (SDO) Monitoring
Railroad tracks, designated as outfalls SW002, and
Access Road, designated as outfall SW003.
Total Suspended Solids (TSS)
Semi-annual monitoring only if coal or coal ash transported through
this drainage area. BASIS: Potential pollutant from drainage area
and BMP effectiveness indicator
Non -polar Oil & Grease (Method
Semi-annual monitoring only if coal or coal ash transported through
1664 SGT-HEM)
this drainage area. BASIS: Potential pollutant from lubricants;
Method 1664 SGT-HEM targets petroleum -based 0&G
pH
Semi-annual monitoring only if coal or coal ash transported through
this drainage area. BASIS: Pollutant indicator and important to
interpreting toxicity potential of metals
Priority Pollutant Metals Ag, As,
Semi-annual monitoring only if coal or coal ash transported through
Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se,
this drainage area. BASIS: Coal combustion waste (CCW)
Tl, and Zn.
constituents
Boron
Semi-annual monitoring only if coal or coal ash transported through
this drainage area. ®BASIS: Coal combustion waste (CCW)
constituent / coal tracer.
STORMWATER BENCHMARKS AND TIERED RESPONSE IV
Rather than limits, North Carolina NPDES Stormwater permits contain benchmark concentrations.
Stormwater benchmarks are numerical action levels for stormwater monitoring. Benchmarks are
not effluent limits, and benchmark exceedances are not permit violations. Benchmarks
provide facilities a tool for assessing the significance of pollutants in stormwater discharges and the
effectiveness of best management practices (BMPs). Benchmark concentrations are intended as
guidelines for the facili ment and implementation of the Stormwater Pollution
Prevention Plan (SPP
Benchmark exceedances require the permittee to increase monitoring, increase management
actions, increase record keeping, and/or install stormwater BMPs in a tiered program. The permit
establishes a tiered approach to specify actions the permittee must take in response to analytical
results above benchmark concentrations (Part II, Section B., following Table 3). The tiered
structure of the permit provides the permittee and NCDEMLR wide flexibility to address issues that
may arise with one or more parameters and/or outfalls.
Metals benchmarks are calculated to mimic acute water quality standards and with the guidance of
NC's Division of Water Resources (DWR). NC DWR follows established federal procedures for
calculating acute standards when developing the benchmarks. Just like the acute standards, metals
benchmarks normally reflect one half of the calculated Final Acute Value (the "1/z FAV"). In most
cases, translation into total recoverable values is based on an assumed hardness of 25 mg/1 and a
total suspended solids (TSS) concentration of 10 mg/l. Acute standards protect aquatic life from
negative impacts of short-term exposure to higher levels of chemicals where the discharge enters a
waterbody. The Stormwater Permitting Program applies this approach because of the ephemeral
nature of rainfall events.
The Division may evaluate results to determine if a smaller suite of parameters for some outfalls is
adequate to characterize potential pollution or BMP effectiveness. For example, one or more metals
or other parameters may serve as an adequate tracer for the presence of ash pollution during
disturbance or ash removal in specific drainage areas at this site. For parameters that do not have a
stormwater benchmark, the Division may develop a benchmark value if appropriate toxicity data
become available or if rising trends in concentrations suggest a persistent source.
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NPDES Stormwater Permit NCS000549
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A summary of the benchmarks in the draft permit, and their basis, is below:
Parameter
Benchmark
Basis
Antimony Sb , m L
0.09
Acute Aquatic Criterion, 1/z FAV
Arsenic (As), m L
0.34
Acute Aquatic Criterion, 1/z FAV
Beryllium (Be), m L
0.065
Acute Aquatic Criterion, 1/z FAV
Cadmium Cd , m L
0.003
Acute Aquatic Criterion, 1/z FAV
1/z FAV, based on (Cr III + Cr VI) acute thresholds
Chromium (Cr), mg/L
0.9
and assumption that industrial activities here are
not a source of hexavalent chromium.
Copper (Cu), m L
0.010
Acute Aquatic Criterion, 1/z FAV
Lead (Pb), m L
0.075
Acute Aquatic Criterion, 1/z FAV
Monitoring only, CCW/Coal Constituent. Hg
influenced by regional transport and wet
Mercury (Hg), ng/L
N/A
deposition. Values above 12 ng/L (NC WQ
standard) should be noted on the DMR but do not
trigger Tier Responses.
Nickel (Ni), m /L
0.335
Acu Aquatic Criterion, 1/z FAV
1/2 FAV, NC -specific, based on 1986 Study on Se
Selenium (Se), mg/L
0.056
impacts in North Carolina
Acute Aquatic Criterion, 1/z FAV. (The Division
Silver (Ag), mg/L
0.0003
notes this value is below the practical quantitation
level (PQL) of 1 µg/L of EPA Method 200.8)
Monitoring only, CCW/Coal Constituent. Narrative
Boron (B), mg/L
N/A
National Recommended Water Quality Criterion.
Monitoring On , CCW/Coal constituent. National
Thallium (TI), mg/L
N/A
Recommended Human Health Criterion.
Zinc Zn , m L
0.126
Acute Aquatic Criterion, 1/z FAV
Total Suspended Solids (TSS),
National Urban Runoff Program (NURP) Study,
mg/L 0
100
1983
Non -Polar Oil & Grease, EPA
Review of other state's daily maximum benchmark
Method 1664 (SGT-HEM),
15
concentration for this more targeted 0&G; NC WQ
mg/L
Standard that does not allow oil sheen in waters.
pH
6-9
NC Water Quality Standard (Range)
STORMWATER POLLUTION PREVENTION PLAN
The proposed permit conditions reflect the Environmental Protection Agency's (EPA) and North
Carolina's pollution prevention approach to stormwater permitting. The Division's maintains that
implementation of Best Management Practices (BMPs) and traditional stormwater management
practices that control the source of pollutants meets the definition of Best Available Technology
(BAT) and Best Conventional Pollutant Control Technology (BCT). The permit conditions are not
numeric effluent limitations but are designed to be flexible requirements for implementing site -
specific plans to minimize and control pollutants in stormwater discharges associated with the
industrial activity. Title 40 Code of Federal Regulations (CFR) §122.44(k)(2) authorizes the use of
BMPs in lieu of numeric effluent limitations in NPDES permits when the agency finds
numeric effluent limitations to be infeasible. The agency may also impose BMP requirements
which are "reasonably necessary" to carry out the purposes of the Act under the authority of 40
CFR 122.44(k) (3). The conditions proposed in this draft permit are included under the authority of
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NPDES Stormwater Permit NCS000549
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both of these regulatory provisions. In essence, the pollution prevention and BMP requirements
operate as limitations on effluent discharges that reflect the application of BAT/BCT.
The permit proposes some language specific to coal fired power plants (and in particular, to those
plants being decommissioned). Determining specific BMPs that are appropriate for the site and
activities are the permittee's responsibility, and the permit strives not to limit what BMPs can be
used. The permittee should also refer to the BMPs described in both EPA's Multi -Sector Permit
(MSGP) and Industrial Stormwater Fact Sheet for Steam Electric Power Generating Facilities (Sector
0) for guidance on pollution prevention measures.
It is important to note that the majority of stormwater at this facility is ultimately routed into the
waste treatment system (ash pond), and those discharges are regulated by the NPDES wastewater
permit.
MERCURY MONITORING REQUIREMENTS
The proposed permit requires mercury to be measured in stormwater samples by EPA Method
1631E, which can detect levels as low as 0.5 ng/l. This requirement is consistent with recent
federal rule -making that requires NPDES permittees to monitor discharges with sufficiently
sensitive test procedures approved under 40 CFR §136. Modifications to 40 CFR §122.44(i) require
a method that has a minimum level (ML) at or below the effluent limit (not applicable here), or the
lowest minimum level (ML) of EPA approved analytical methods for the measured parameter.
Based on results, Method 1631E will be required to quantify levels in these discharges. NC DEMLR
understands that this method is more costly and requires a more intensive sampling protocol than
most other parameters, and that fish tissue sampling will be provided during the permit cycle.
Therefore, no benchmark applies that would trigger tiered response actions. Proposed permit
provisions also allow the permittee to use field blank and/or method blank concentrations to adjust
reported mercury levels as long as do umented is submitted with the Data Monitoring Report
(DMR).
FLEXIBILITY IN TIER RESPONSE
Tier Two actions (upon two consecutive bench exceedances at an outfall) proposed in this
draft permit differs slightly from the Program's standard template and includes step 6. That step
provides an opportunity for the permittee to propose an alternative monitoring plan for
approval by the Region.
Alternatively, in lieu of steps 2 and 3, the permittee may, after two consecutive exceedances,
exercise the option of contacting the DEMLR Regional Engineer as provided below in Tier Three.
The Regional Engineer may direct the response actions on the part of the permittee as provided in
Tier Three, including reduced or additional sampling parameters or frequency.
If pursuing the alternative above after two consecutive exceedances, the permittee may propose an
alternative monitoring plan for approval by the Regional Engineer.
The permit therefore allows the permittee to petition the Regional Office for monitoring changes
sooner than Tier Three (upon any four benchmark exceedances) and gives guidance on one option
to take. For example, the permitttee may request that mercury only be monitored semi-annually
under the tiers, or that only parameters over the benchmark be monitored more frequently. In this
way, changes to the monitoring scheme for any outfall could be handled outside of a permit
modification.
Fact Sheet
NPDES Stormwater Permit NCS000549
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OTHER PROPOSED REQUIREMENTS
• It is standard for Stormwater Pollution Prevention Plan (SPPP) requirements to include an
annual certification that stormwater outfalls have been evaluated for the presence of non-
stormwater discharges, and if any are identified, how those discharges are permitted. The
draft permit requires this facility to submit the first certification to DEMLR no later
than 90 days after the effective date of the permit (Part II, Section A.).
• Requirement to submit a request for permit modification if the facility identifies or creates
any new outfalls, removes outfalls, or alters any drainage area that changes potential
pollutants. This site may trigger this requirement during demolition or ash removal
activities.
• Standard text that allows a permittee to forgo collecting samples outside of regular
operating hours was omitted in Part II because this power plant is not currently operating.
The Division expects the permittee to apply best professional judgment and consider the
safety of its personnel in fulfilling sampling obligations under the permit.
• Proposed federal regulations will require electronic submittal of all discharge monitoring
reports (DMRs). If a state does not establish a system to receive such submittals, then
permittees must submit DMRs electronically to the Environmental Protection Agency (EPA).
The Division anticipates that these regulations will be adopted and is beginning
implementation. Permit provisions addressing this impending requirement is included in
Part III, Section B. (General Conditions), 3.e.
• Quarterly Qualitative/Visual nitoring to assure regular observation of outfalls
throughout year.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice: [Date]
Permit Scheduled to Iss [Date]
STATE CONTACT:
If you have any questions about any of the above information or the attached permit, please contact
Mike Randall at [phone] or [e-mail].
Fact Sheet
NPDES Stormwater Permit NCS000549
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