NCS000581_Roxboro Fact Sheet to Notice_20160823

DENR/DEMLR
FACT SHEET FOR NPDES STORMWATER PERMIT DEVELOPMENT
NPDES No. NCS000581
BACKGROUND
The Roxboro facility is an electric generating facility consisting of four coal-fired units with a total
net capacity of 2462 MWe.
Duke Energy Progress, Inc. has not treated, stored or disposed of any significant materials in a
manner that would allow exposure to stormwater in the drainage areas for outfalls SW -A and SW -3
and has no plans to treat, store or dispose of significant materials in the drainage areas. No
stormwater runoff from material loading or unloading areas flows to outfalls SW -A and SW -3.
Drainage from areas where coal, limestone, and gypsum are stored, loaded, or unloaded drain to the
coal pile runoff pond - a permitted NPDES wastewater outfall to Hyco Lake. Chemicals or processes
with a potential to contaminate stormwater are located in buildings or covered by shelters. Outside
storage areas contain inert materials. Incidental dust associated with coal, limestone or gypsum
transport may contribute to stormwater runoff to outfall SW -A. Truck wheels are washed and truck
beds are covered prior to driving through the drainage areas associated with SW -A and SW -3.
Various brands of commercial herbicides, i.e., Roundup, Crossbow, are used to control weeds and
other unwanted plant growth for security reasons. These herbicides are applied by licensed
applicators, or by persons under the immediate supervision of a licensed applicator. Fertilizers,
pesticides and other soil conditioners are not used in the drainage area associated with SW -A or
SW -3. No hazardous waste treatment, storage, or disposal occur in the drainage areas associated
with SW -A and SW -3.
Fact Sheet
NPDES Stormwater Permit NCS000581
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Facility Information
Applicant/ Facility Name:
Duke Energy Progress, Inc.
Applicant Address:
410 South Wilmington Street, Raleigh North Carolina 27601
Facility Address:
1700 Dunnaway Road, Roxboro, North Carolina 27343
Permitted Flow:
N/A (Stormwater Discharges Only)
Industrial Activities:
Primary SIC Code: 4911- Electric Services
Permit Status:
New NPDES Stormwater Permit
County:
Person County
Miscellaneous
Receiving Stream:
H ko Reservoir Regional Office: Asheville
Stream Classification:
WS -V, B State Grid USGS Quad:
303(d) Listed?
Hg, statewide Permit Writer: Mike Randall
Subbasin:
22-58- 0.5 Date: August 23, 2016
Facility Location: Lat. 36'29' 16"N Long. 79° 4' 19" W
BACKGROUND
The Roxboro facility is an electric generating facility consisting of four coal-fired units with a total
net capacity of 2462 MWe.
Duke Energy Progress, Inc. has not treated, stored or disposed of any significant materials in a
manner that would allow exposure to stormwater in the drainage areas for outfalls SW -A and SW -3
and has no plans to treat, store or dispose of significant materials in the drainage areas. No
stormwater runoff from material loading or unloading areas flows to outfalls SW -A and SW -3.
Drainage from areas where coal, limestone, and gypsum are stored, loaded, or unloaded drain to the
coal pile runoff pond - a permitted NPDES wastewater outfall to Hyco Lake. Chemicals or processes
with a potential to contaminate stormwater are located in buildings or covered by shelters. Outside
storage areas contain inert materials. Incidental dust associated with coal, limestone or gypsum
transport may contribute to stormwater runoff to outfall SW -A. Truck wheels are washed and truck
beds are covered prior to driving through the drainage areas associated with SW -A and SW -3.
Various brands of commercial herbicides, i.e., Roundup, Crossbow, are used to control weeds and
other unwanted plant growth for security reasons. These herbicides are applied by licensed
applicators, or by persons under the immediate supervision of a licensed applicator. Fertilizers,
pesticides and other soil conditioners are not used in the drainage area associated with SW -A or
SW -3. No hazardous waste treatment, storage, or disposal occur in the drainage areas associated
with SW -A and SW -3.
Fact Sheet
NPDES Stormwater Permit NCS000581
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FACILITY STORMWATER DRAINAGE
Outfall SW -A - North Loop of Plant
The drainage area for outfall SW -A is located north of the plant and is enclosed by a rail line.
Stormwater flows through a 24 inch diameter culvert under the rail line through riprap into a
vegetated swale approximately 150 feet to Hyco Lake.
Outfall SW -3 - West Access Road
Drainage area for outfall SW -3 contains a warehouse, grassy swale and access road where chemical
deliveries take place.
No conventional treatment is provided for stormwater at outfall SW -3. Outfall SW -3 flows over a
vegetative buffer.
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."
PROPOSED MONITORING FOR STORMWATER DISCHARGES
The Division considered potential pollutants from past and present industrial activities (coal-fired
electric generation, plant decommissioning, and future ash removal) and data submitted in the
application submitted December 15, 2014. Sampling included Sampling for outfall SW -A included
0&G, BOD, COD, TSS, TDS, Total Nitrogen, Total Phosphorus, pH, Temperature, Antimony, Arsenic,
Barium, Beryllium, Boron, Calcium, Hardness, Chloride, Cobalt, Copper, Fluoride, Iron, Mercury,
Molybdenum, Nickel, Selenium, Sulfate, Thallium, and Zinc, Aluminum, Magnesium, Magnesium,
Nitrate, and TKN.
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
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removal through the drainage area). Below is a table of the proposed monitoring for each outfall at
the site.
All outfalls ultimately discharge to Hyko Reservoir.
Stormwater Discharge Outfall (SDO) Monitoring
SW -A and SW -3
Total Suspended Solids (TSS)
Semi-annual monitoring (quarterly if coal or ash transport). BASIS:
Potential pollutant from drainage area and BMP effectiveness
indicator.
Priority Pollutant Metals Ag, As,
Quarterly 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; includes metals incorporated into the coal ash
monofill constructed for the company's Mayo Steam Electric Plant
(another site).
Boron
Quarterly monitoring only if coal or coal ash transported through
this drainage area. BASIS: Coal combustion waste (CCW)
constituent coal tracer.
pH
Quarterly monitoring only if coal or coal ash transported through
this drainage area. BASIS: Pollutant indicator and important to
interpreting toxicity potential of metals.
STORMWATER BENCHMARKS AND TIERED RESPONSE
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 facility's development and implementation of the Stormwater Pollution
Prevention Plan (SPPP).
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 Il, Section B., following Table 10). 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 "Y2 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/1. 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
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NPDES Stormwater Permit NCS000581
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become available or if rising trends in concentrations suggest a persistent source. A summary of
the benchmarks in the draft permit, and their basis, is below:
Parameter
Benchmark
Basis
Antimony (Sb), m L Total
0.09
Acute Aquatic Criterion, 1/2 FAV
Arsenic (As), m L Total
0.34
Acute Aquatic Criterion, 1/2 FAV
Beryllium (Be), m L Total
0.065
Acute Aquatic Criterion, 1/2 FAV
Cadmium (Cd), m L Total
0.003
Acute Aquatic Criterion, 1/2 FAV
1/2 FAV, based on (Cr III + Cr VI) acute thresholds
Chromium (Cr), mg/L (Total)
0.9
and assumption that industrial activities here are
not a source of hexavalent chromium.
Copper (Cu), m L Total
0.010
Acute Aquatic Criterion, Y2 FAV
Lead (Pb), m L Total
0.075
Acute Aquatic Criterion, 1/2 FAV
Monitoring only, CCW/Coal Constituent. Hg
influenced by regional transport and wet
Mercury (Hg), ng/L (Total)
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 Total
0.335
Acute Aquatic Criterion, 1/2 FAV
Polychlorinated biphenyl
Detected
NC Water Quality Standards vs. present Arochlors
compounds (PCBs), µg/L
quantitation levels (higher than standard)
Y2 FAV, NC -specific, based on 1986 Study on Se
Selenium (Se), mg/L (Total)
0.056
impacts in North Carolina
Acute Aquatic Criterion, 1/2 FAV. (The Division
Silver (Ag), mg/L (Total)
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 Only, CCW/Coal constituent. National
Thallium (Tl), mg/L (Total)
N/A
Recommended Human Health Criterion.
Zinc (Zn), m L Total
0.126
Acute Aquatic Criterion, 1/2 FAV
Total Suspended Solids (TSS),
National Urban Runoff Program (NURP) Study,
mg/L
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
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NPDES Stormwater Permit NCS000581
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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
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/1. 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 documented is submitted with the Data Monitoring Report
(DMR).
FLEXIBILITY IN TIER RESPONSES
Tier Two actions (upon two consecutive benchmark 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.
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NPDES Stormwater Permit NCS000581
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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 or
otherwise authorized. 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 Monitoring to assure regular observation of outfalls
throughout year.
SECTION D ELECTRONIC REPORTING OF MONITORING REPORTS [G.S. 143-215.1(b)]
Federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and
program reports and specify that, if a state does not establish a system to receive such submittals,
then permittees must submit monitoring data and reports electronically to the Environmental
Protection Agency (EPA). The final NPDES Electronic Reporting Rule was adopted and became
effective on December 21, 2015.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice: [Date]
Permit Scheduled to Issue: [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 NCS000581
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