NCS000589_Weatherspoon FACT SHEET_20160915

DENR/DEMLR
FACT SHEET FOR NPDES STORMWATER PERMIT DEVELOPMENT
NPDES No. NCS000589
BACKGROUND
Duke Energy's Weatherspoon Steam Station was a coal fired steam electric plant in Robeson
County. The facility was retired and then demolished in 2013. In 2008, the Division of Water
Quality issued an NPDES wastewater permit that included three stormwater outfalls potentially
influenced by ash transport along the entrance road during an ash reuse project that discharged to
waters of the state. Those outfalls were removed from that permit in 2011, after the conclusion of
the activity. The company is applying for a separate NPDES Stormwater permit for these outfalls
because the discharge points will again be impacted by ash transport in the near future.
In addition to NPDES wastewater discharge permit NC0005363, the facility also holds: NCG560006
(General NPDES WW permit to apply pesticides), 6094T (NC air permit), WQ0000020 (ash
utilization permit) and NCD000830620 (Hazardous wastes RCRA permit). The facility is subject to
federal requirements of 40 CFR §423 - Steam Electric Power Generation. This category is subject to
federal NPDES stormwater discharge permit requirements per 40 CFR §122.26 (b)(14)(vii). Duke
Energy Progress has not yet submitted a decommissioning plan for ash ponds on the site but will
notify the Division when ash pond closure will begin.
This facility discharges to the Lumber River. There is a statewide total maximum daily load (TMDL)
for mercury (Hg), approved in September 2012. No specific reductions or Hg limits are required
from NPDES Stormwater permittees at this time. There are no threatened or endangered aquatic
life species on or within a mile of the plant site; however there is a State -listed endangered reptile
(Eastern Diamondback Rattlesnake), as well as State -listed endangered or threatened plant species
(Carolina Bogmint, Comfortroot, and Florida Yellow -eyed grass) within a mile of the site (from
Natural Heritage Data Explorer, accessed 9/13/2016).
Fact Sheet
NPDES Stormwater Permit NCS000589
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Facility Information
Applicant/Facility Name:
Duke Energy Progress, LLC - W.H. Weathers oon Plant
Applicant Mailing Address:
801 Sutton Steam Plant Road; Wilmington, North Carolina 28401
Facility Address:
491 Power Plant Road; Lumberton, North Carolina 28358
Permitted Flow:
N/A (Stormwater Discharges Only)
Industrial Activities:
Primary SIC Code: 4911- Electric Services
Permit Status:
New NPDES Stormwater Permit
County:
Robeson County
Miscellaneous
Receiving Stream:
Lumber River Regional Office: Fayetteville
Stream Classification:
C;Sw State Grid / USGS Quad: I22NE
303(d) Listed?
Hg, statewide Permit Writer: B. Geor oulias
Subbasin:
03-07-51 Date: September 15, 2016
Facility Location: Lat. 34° 34'58" N Long. 78° 58'25" W
BACKGROUND
Duke Energy's Weatherspoon Steam Station was a coal fired steam electric plant in Robeson
County. The facility was retired and then demolished in 2013. In 2008, the Division of Water
Quality issued an NPDES wastewater permit that included three stormwater outfalls potentially
influenced by ash transport along the entrance road during an ash reuse project that discharged to
waters of the state. Those outfalls were removed from that permit in 2011, after the conclusion of
the activity. The company is applying for a separate NPDES Stormwater permit for these outfalls
because the discharge points will again be impacted by ash transport in the near future.
In addition to NPDES wastewater discharge permit NC0005363, the facility also holds: NCG560006
(General NPDES WW permit to apply pesticides), 6094T (NC air permit), WQ0000020 (ash
utilization permit) and NCD000830620 (Hazardous wastes RCRA permit). The facility is subject to
federal requirements of 40 CFR §423 - Steam Electric Power Generation. This category is subject to
federal NPDES stormwater discharge permit requirements per 40 CFR §122.26 (b)(14)(vii). Duke
Energy Progress has not yet submitted a decommissioning plan for ash ponds on the site but will
notify the Division when ash pond closure will begin.
This facility discharges to the Lumber River. There is a statewide total maximum daily load (TMDL)
for mercury (Hg), approved in September 2012. No specific reductions or Hg limits are required
from NPDES Stormwater permittees at this time. There are no threatened or endangered aquatic
life species on or within a mile of the plant site; however there is a State -listed endangered reptile
(Eastern Diamondback Rattlesnake), as well as State -listed endangered or threatened plant species
(Carolina Bogmint, Comfortroot, and Florida Yellow -eyed grass) within a mile of the site (from
Natural Heritage Data Explorer, accessed 9/13/2016).
Fact Sheet
NPDES Stormwater Permit NCS000589
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WHY THIS FACILITY IS SUBIECT 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 Weatherspoon has ceased, coal ash is still present at the site.
Coal ash will be disturbed and/or transported as ash pond close-out procedures are carried out.
PROPOSED MONITORING FOR STORMWATER DISCHARGES
Stormwater from the demolished former coal plant site is routed to the cooling pond and is
included in the proposed NPDES wastewater permit. This draft stormwater permit covers the three
stormwater outfalls that drain runoff from the access road along which ash will be transported.
The Division considered potential pollutants from past and present industrial activities (coal-fired
electric generation, plant decommissioning, and future ash removal) and data submitted with the
NPDES Stormwater application. Sampling included conventional pollutants [Oil and Grease
(O&G), Chemical Oxygen Demand (COD), and Total Suspended Solids (TSS)]; applicable effluent
guideline pollutants [copper (Cu), iron (Fe), arsenic (As), selenium (Se), pH, and temperature]; as
well as other coal ash associated pollutants [chloride, fluoride, sulfate (SO4), mercury (Hg),
aluminum (Al), antimony (Sb), barium (Ba), boron (B), calcium (Ca), cadmium (Cd), chromium (Cr),
lead (Pb), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), thallium (Tl), zinc
(Zn), Total Dissolved Solids (TDS), specific conductivity, hardness, and pH]. Sampling results from
9/30/2014 were submitted with EPA Form 2F as part of the NPDES stormwater permit application
in 2016. The same stormwater event samples for SW -2 and SW -3 were included in the seep report
submitted with DWR's NPDES wastewater permit application (instead designated as S-07 and S-08,
respectively); however, these two outfalls are not seeps. These outfalls are influenced by
groundwater.
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NPDES Stormwater Permit NCS000589
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None of the 9/30/2014 sample results was above current stormwater benchmarks for any of the
outfalls (see p. 8 of this Fact Sheet). DEMLR's review noted that mercury was not sampled with a
method sensitive enough to quantify levels below 50 ng/1; however, the proposed draft permit
requires Method 1631 that quantifies lower levels be used for Hg analysis. The draft permit also
requires the company to submit to DEMLR a copy of annual fish tissue sampling results for arsenic,
mercury, and selenium obtained per DWR wastewater permit requirements.
The company's permit application indicated outfalls SW -2 and SW -3 were influenced by
groundwater and have non-stormwater discharges. The Division requested an evaluation of the
discharge characteristics to demonstrate such discharges would be allowable under an NPDES
Stormwater permit. Allowable non-stormwater discharges include uncontaminated groundwater
(See Part IV, 3. in the proposed permit).
These two outfalls had been sampled multiple times between 3/2014 and 4/2016 (Five events at
SW -2 and four events at SW -3, including the stormwater event in 2014). In August 2016, the
company submitted additional information in support of dry weather discharges being attributable
to uncontaminated groundwater. Combined average concentrations from SW -2 and SW -3
discharge sampling events were compared to background groundwater well concentrations (23
sample events from 2010-2016) and to toe drain concentrations (up to five sample events from
each of four toe drains). Boron levels were below detectable in all stormwater outfall samples, and
sulfate (SO4) levels were an order of magnitude lower than both background well and toe drain
data (note that all three averages were below the current SO4 stormwater benchmark of 200 mg/1).
Alkalinity, iron, arsenic, chromium, copper, and lead average concentrations were significantly
higher in the toe drain samples than in SW -2 and SW -3 discharges and in the background
groundwater well. Individual sample results for both SW -2 and SW -3 showed concentrations were
not highly variable (i.e., combined averages did not disguise particularly high values), and no
samples exceeded current stormwater benchmarks. Mercury values that were reported from a
more sensitive test in four samples were below 2 ng/1. The Division concurred with the conclusion
that groundwater discharges from SW -2 and SW -3 outfalls would be permissible under the NPDES
stormwater permit unless circumstances or characteristics change.
The proposed draft permit does contain language stating that if discharge characteristics or
influences change at SW -2 or SW -3 such that discharges contain contaminated groundwater or
other waters not authorized by the permit, the permittee will be required to obtain or modify a
wastewater permit to cover these discharges or find an alternative to direct discharge.
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
transport through the drainage area). Below is a table of the proposed monitoring for the outfalls
at the Weatherspoon site. All outfalls ultimately discharge to the Lumber River.
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NPDES Stormwater Permit NCS000589
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Stormwater Discharge Outfall (SDO) Monitoring
SW -1, SW -2, SW -3
Drainingaccess road where ash hauling will occur
Polychlorinated Biphenyls
Semi-annual monitoring; may be discontinued after the first
(PCBs)
year (two samples) if not detected. BASIS: Electrical equipment
onsite prior to decommissioning may have contained PCBs, which
persist in the environment if ever released. If all PCBs have been
removed and past releases cleaned up, these compounds should
not be detected.
Total Suspended Solids (TSS)
Semi-annual monitoring. BASIS: Potential pollutant from
drainage area and BMP effectiveness indicator, particularly during
ash hauling activities. Quarterly monitoring if coal or coal ash
transported through this drainage area.
Non -polar Oil & Grease (Method
Semi-annual monitoring. BASIS: Potential pollutant from
1664 SGT -HEM)
lubricants; Method 1664 SGT -HEM targets petroleum-based O&G.
Quarterly monitoring if coal or coal ash transported through this
drainage area.
pH
Semi-annual monitoring. BASIS: Pollutant indicator and
important to interpreting toxicity potential of metals. Quarterly
monitoring if coal or coal ash transported through this drainage
area.
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. Monitoring is quarterly because these outfalls will be
impacted when coal ash hauling activities commence.
Boron
Quarterly monitoring only if coal or coal ash transported through
this drainage area. BASIS: Coal combustion waste (CCW)
constituent / coal tracer. Monitoring is quarterly because these
outfalls will be impacted when coal ash hauling activities
commence.
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 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
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NPDES Stormwater Permit NCS000589
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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 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.
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, 1/2 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
q ( g )
1/2 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)
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NPDES Stormwater Permit NCS000589
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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
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 One actions proposed in this draft differs slightly from the Program's standard template. A
single benchmark exceedance prompts immediate monthly monitoring for all parameters. This
change is consistent with power plant permits most recently issued in May 2016 and is based on
public comments received on those draft permits and the intensity of activities during ash removal.
Tier Two actions (upon two consecutive benchmark exceedances at an outfall) proposed in this
draft permit also differs from the Program's standard template and includes step S. That step
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NPDES Stormwater Permit NCS000589
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provides an opportunity for the permittee to propose an alternative monitoring plan for
approval by the Region:
4. 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
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.
OTHER PROPOSED REQUIREMENTS
• 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 ash removal activities.
• Standard text that allows a permittee to forgo collecting samples outside of regular facility
operating hours was modified in Part II because this power plant has been decommissioned
and 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.
FISH TISSUE MONITORING
Weatherspoon's proposed wastewater NDPES permit NC0005363 requires fish tissue monitoring
for arsenic (As), selenium (Se), and mercury (Hg) near the ash pond discharge each year. The
proposed stormwater permit requires the permittee to submit a copy of monitoring results to
the DEMLR Stormwater Program (Central Office) within 30 days of receiving results and indicate
the location of sampling in relation to stormwater discharge outfalls. DEMLR is requiring the fish
tissue analysis results be submitted separately to ensure Stormwater Program staff who are not in the
Division of Water Resources receive results and have an opportunity for review.
PROPOSED SCHEDULE FOR PERMIT ISSUANCE:
Draft Permit to Public Notice: September 2016 (est.)
Permit Scheduled to Issue: November 2016 (est.)
STATE CONTACT:
If you have any questions about any of the above information or the attached permit, please contact
Bethany Georgoulias at [phone] or [e-mail].
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NPDES Stormwater Permit NCS000589
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STORMWATER SAMPLE RESULTS FROM WEATHERSPOON 30/2014, FROM APPLICATION SUBMITTAL
Parameter
Current Stormwater
Benchmark
Outfall SW -1
(mg/1)
Outfall SW -2
(mg/1)
Outfall SW -3
(mg/1)
Oil and Grease
30 (15, non -polar)
<5.0
<5.0
<5.0
Aluminum
0.75 mg/1
0.086
0.041
0.058
Antimony
0.09 mg/1
<0.001
<0.001
<0.001
Arsenic
0.34 mg/1
0.0027
<0.001
<0.001
Barium
N/A
0.018 mg/1
0.039 mg/1
0.022 mg/1
Boron
N/A
<0.05 mg/1
<0.05 mg/1
<0.05 mg/1
Cadmium
0.003 mg/1
<0.001
<0.001
<0.001
Chromium
0.9 (Cr III) mg/1,
0.016 (Cr VI) mg/1
<0.001
<0.001
<0.001
Copper
0.010 mg/1
<0.001
<0.001
<0.001
Iron
N/A
2.5 mg/1
0.619 mg/1
0.319 mg/1
Lead
0.075 mg/1
<0.001
<0.001
<0.001
Magnesium
32 mg/1
0.723
0.918
0.364
Manganese
N/A
0.030 mg/1
0.013 mg/1
<0.005 mg/1
Mercury
12 ng/1
<50 ng/1*
<50 ng/l*
<50 ng/l*
Molybdenum
510 mg/1
<0.001
<0.001
<0.001
Nickel
0.335 mg/1
<0.001
<0.001
<0.001
Selenium
0.056 mg/1
<0.001
<0.001
<0.001
Silver
0. 3 Vg/1
Not sampled
Not sampled
Not sampled
Thallium
N/A
0.501 µ /l
0.39 µ /1
<0.2 µg/l
Zinc
0.126 mg/1
0.011
<0.005
<0.005
Hardness
N/A (mg/1 CaCO3)
25.9
8.65
6.39
TSS
100 mg/1
<5
<5
<5
BOD
30 mg/1
Not provided
Not provided
Not provided
COD
120 mg/1
<20
<20
<20
pH
6-9 SU
6.37
7.3
7.52
Total Nitrogen
30 mg/1
Not provided
Not provided
Not provided
Total Phosphorus
2 mg/1
Not provided
Not provided
Not provided
Chloride
860 mg/1
3.4
3.9
2.3
Fluoride
6 mg/1
<0.1
<0.1
<0.1
Sulfate
500 mg/1
1 1.2
5.1
1 2.3
* More sensitive EPA Method 1631E is required for Hg analysis in proposed permit.
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