NC0003425_Comments_20160101 (22)

NC0003425 — Roxboro Steam Electric Station
Comments from Harry Sideris from Duke Energy:
1. On page 2 of 23 list extracted groundwater as potential flows to outfalls 003 and 001
Response: The groundwater flow is not and existing flow. The Division prefers to do a permit
modification in the future when the groundwater treatment system is designed and the wastewater is
characterized.
2. On page 2 of 23 list yard sump overflow as potential flow for outfall 003.
Response: The Division will add yard sump overflow to the description of wastewaters contributing
to outfall 003.
3. On page 2 of 23 list discharge from outfall 005 (cooling Tower Blowdown) as a potential
contributing flow for outfall 012.
Response: The Division will add the discharge from outfall 005 (cooling tower blowdown) to the
description of wastewaters contributing to outfall 012B.
4. On page 2 of 23 list discharge from outfall 008 (domestic wastewater) as a potential contributing
flow to outfall 012.
Response: The Division will add the discharge from outfall 008 (domestic wastewaters) to the
description of wastewaters contributing to outfall 012B.
5. On page 2 of 23 list the retention basin (outfall 012A) as a potential flow path for landfill leachate.
Response: The Division will add the discharge landfill leachate to the description of wastewaters
contributing to outfall 012A.
6. On page 2 of 23 list anhydrous ammonia testing waters and emergency flow to the contributing
flows for outfall 003.
Response: The Division will add the anhydrous ammonia testing and emergency flow to the
description of wastewaters contributing to outfall 003.
7. On page 4 of 23 the sampling frequency for toxicity test for outfall 001 should be clarified as
Quarterly to align with condition A.(14).
Response: The Division is unable to grant this request, this requirement was imposed by EPA and it
is consistent with other Duke permits.
8. On page 5 of 23 and 7 of 23 the requirement for turbidity would not apply to internal outfall 002.
Response: The Division agrees to remove turbidity from internal outfall 002 and apply the
monitoring requirement at outfall 003.
9. On page 5 of 23 the requirement related to the schedule of compliance for the discharge of bottom
ash in Condition A.(2) should be clarified to state that no discharge of bottom ash only applies to
bottom ash generated after April 30, 2021 not November 1, 2018.
Response: The Division agrees to clarify the statement to read that the requirement only applies to
bottom ash generated after April 30, 2021 which is the correct date for cessation of bottom ash
approved in the permit.
10. On page 7 of 23 Duke request that the dewatering phase flow limit is increased to 2 MGD.

Response: The Division agrees to increase the limit to 2 MGD, this limit will represent the capacity
of the treatment system to be installed.
11. On page 7 of 23 remove pH limit for ash pond outfall 002.
Response: Since the wastewater from the ash pond is combined with cooling water the pH limit will
be removed.
12. On page 9 of 23 add language to description of cooling tower blowdown path to say it can also be
discharged to outfall 012.
Response: The Division will clarify the language in the Supplement to Permit Cover Sheet to include
the blowdown at outfall 012B.
13. On page 7 of 23 remove pH limits from FGD outfalls.
Response: The Division is unable to grant this request, pH limits are applicable according to 40 CFR
423.
14. On page 13 of 23 delete the words biological treatment from footnote #2 for outfalls 010 and 011
(FGD).
Response: The Division agrees to remove language as final treatment is not yet defined.
15. On page 13 of 23 Duke request that two internal outfalls, 012A and 012B, are permitted for possible
effluent from two waste retention basins.
Response: The Division will modify the permit to include two outfalls instead of one for the
proposed treatment systems.
16. On page 14 of 23 add the following language to the condition A. (13): "all previously identified
seeps from this facility are contributing flows to permitted outfalls 001 or 003, there are no seeps the
discharge to jurisdictional waters.
Response: The Division will clarify the language in the special condition by listing seeps and the
receiving outfalls.
Southern Environmental Law Center on behalf of the Roanoke River Basin Association:
No limits for arsenic, mercury, lead, selenium, thallium, boron, barium, chloride, aluminum, or
copper for the ash basin (outfall 002) or the discharge canal (outfall 003).
Response: The need for water quality based effluent limits is determined according to a reasonable
potential analysis (RPA). The RPA procedure utilized by the Division is in accordance with EPA's
regulation at 40 CFR 122.44(d) (1). Permit limits are added only if the results of the RPA suggest
potential for exceeding the water quality standards, and are not arbitrarily assigned. Outfall 002 is an
internal outfall where water quality standards are not applicable as limits. The discharge to waters of
the state is outfall 003 where an RPA was conducted and limits implemented accordingly.
2. No limit for selenium at 006.
Response: The RPA for outfall 006 was revised and limits for selenium were added for outfall 006.
3. No limits for FGD metals until 2023, mercury limit too high.

Response: The extended deadlines for Compliance with the New Effluent Limitations have been
established in accordance with 40 CFR 423. Duke provided justification for the compliance
schedule, which is well within authorized by the federal rule. The FGD are internal outfalls where
the TBELs are implemented as per 40 CFR 423. The mercury limit is a TBEL designed for a
specific waste stream and is implemented to provide a uniform treatment level that can be achieved
by all power plants in the country. TBELS "are intended to represent the greatest pollutant
reductions that are economically achievable for an industry".
4. DEQ should implement BAT limits using BPJ for the coal ash discharge. (same limits and
technology as decanting and dewatering at Sutton and Riverbend)
Response: The EPA has recently conducted a comprehensive study of all waste streams generated
by the power plants and considered all potential pollutants of concern. Based on the results of this
study the EPA used all applicable rules and regulations and produced an update to 40 CFR 423 in
2015. The EPA decided that TBELs for all parameters of concern are not necessary because
"Effluent limits and monitoring for all pollutants of concern is not necessary to ensure that the
pollutants are adequately controlled because many of the pollutants originate from similar sources,
have similar treatabilities, and are removed by similar mechanisms. Because of this, it may be
sufficient to establish effluent limits for one pollutant as a surrogate or indicator pollutant that
ensures the removal of other pollutants of concern." Therefore, the effluent guidelines have been
recently promulgated in there is no need for BPJ decisions. The Final Permit will incorporate the
requirement to use physical -chemical treatment for decanting and dewatering phases to treat the ash
pond water.
5. Proposed permit abandons tributary streams to Duke Energy's coal ash pollution violating the
CWA. DEQ can't designate a stream as an outfall. (001)
Response: An Effluent Channel Determination was completed on December 15, 2016. Duke will
request that the USACOE complete a jurisdictional determination for the site. The Division will
review the results and implement requirements accordingly.
6. Compliance boundaries include "extensions" areas for East and West Ash basins. These areas
should not be part of the waste treatment system.
Response: On July 8, 2016, DEQ requested that Duke Energy .. provide data and conduct additional site
assessment as needed to cbaractente the distribution of coal asb residuals (CCR)... in the following areas for the
purpose of addressing these areas as part of the comprehensive site assessment at Roxboro Steam
Electric Plant:
Area directly east of the East Ash Basin, known as the "Unnamed eastern Extension Basin"
to include the discharge canal that runs north along the eastern side of the East Ash Basin
Area directly south of the West Ash Basin and encompasses the three `fingers' of the
damned watershed and the drainage canal that runs north along the west side of the West
Ash Basin
DEQ also requested that facility site maps be updated with revised waste boundaries and proposed
compliance boundaries. Duke Energy submitted a site assessment work plan August 22, 2016, and
DEQ approved it November 23, 2016. However, in DEQ's November letter, DEQ states that it
cannot approve the proposed revised compliance boundary locations for the subject facilities at tbis time, but would
provide further direction in the near future. As of the date of this response, DEQ has not approved

the proposed compliance boundaries. Until revised compliance boundaries are approved, these
areas are subject to clean up under 15A NCAC 02L.
7. Permit illegally authorizes the treatment plant to leak. The permit violates anti -backsliding
requirements and BAT requirements.
Response: Seepage through earthen dams is common and is an expected consequence of
impounding water with an earthen embankment. Even the tightest, best -compacted clays cannot
prevent some water from seeping through them. Seepage is not necessarily an indication that a dam
has structural problems, but should be kept in check through various engineering controls and
regularly monitored for changes in quantity or quality which, over time, may result in dam failure. In
addition, toe drains lower the phreatic surface in the dam and improve its stability by keeping it dry.
Excessive dam wetness can cause a collapse of the dam.
The statement in the fact sheet stating than precipitation, adsorption and settling has been
determined to be BAT is no longer applicable and was removed.
8. Permitting a water of the state as a component of the treatment system violates the CWA.
Response: An Effluent Channel Determination was completed on December 15, 2016. The
USACOE will complete a jurisdictional determination for the site. The Division will review the
results and implement requirements accordingly.
9. Ash should be removed from the unlined pit to lined landfill.
Response: The decision regarding the ultimate closure of the ash ponds will be made outside of the
NPDES permitting process after the DEQ evaluates the Corrective Action Plan submitted by Duke.
10. DEQ has acknowledged that zero discharge is attainable for seeps but fails to require that solution
or to impose corresponding TBELs or any schedule of completion.
Response: � 130A-309.210 of the Coal Ash Management Act (CAMA) of 2014 requires owners of
coal combustion residuals surface impoundments to identify and assess all discharges from the
impoundments and to implement corrective action to prevent unpermitted discharges from the
impoundments to the surface waters of the state. Identification of discharges includes engineered
channels designed or improved for the purpose of collecting water from the toe of the
impoundment (toe drains), as well as non -engineered seeps and weeps. One method of proposed
corrective action allowed under the Act is to make application for a National Pollutant Discharge
Elimination System (NPDES) permit amendment to bring the unpermitted discharge under permit
regulations. This approach was approved by the EPA. In addition, the Division expects that many
seeps would disappear after the ash pond is dewatered. Some seeps already disappear at the
Riverbend Station after the water surface in the pond is lowered.
11. Permit should require dry handling of all coal ash, permit allows bottom ash sluicing until 2021
Response: The extended deadlines for compliance with the New Effluent Limitations have been
established in accordance with the 40 CFR 423. Duke provided justification for the compliance
schedule, which is well within authorized by the federal rule.
12. DEQ cannot permit the existing seeps or permit in advance unidentified and thus unpermitted
discharges.

Response: The permit does not authorize unidentified seeps in advance, if the new seeps are found,
Duke Energy shall apply for a permit modification and the permit will be re -opened, the modified
permit will be publically noticed and open for comments from all interested parties. The permit
language will be modified to make this DEQ position more clear.
13. Draft permit inconsistent with the removed substances provision in the permit.
Response: The disposal of the coal ash in wet lagoons has been authorized by the EPA in
accordance with the CWA. New federal regulations will gradually phase out the use of coal ash
lagoons. The permit does not allow the discharge of coal ash from any of the outfalls.
14. Permit Threatens the safety of the Roxboro Dam.
Response: The Dam is regulated by the Dam Safety program at DEMLR, it is not subject to the
NPDES regulations. The DEMLR provides regular inspections of all dams at power plants and
oversees the necessary repair and maintenance activities.
15. Duke is violating water quality standards on Hyco Lake, Sargents Creek and unnamed tributaries.
Response: The location referenced in the letter is included in the permit is an outfall for seeps that
includes monitoring for metals and limits for sulfate, selenium and arsenic. In addition, the permit
has requirements for sampling surface waters. Water quality standards violations will be addressed
through he compliance process.
16. The ash pond discharges groundwater via direct hydrological connection.
Response: The NPDES program regulates point source discharges to the Waters of the US, the
infiltration of the wastewater to the groundwater does not fit the definition of the point source
discharge. The groundwater contamination is being regulated under a separate program within
DWR. The comprehensive impact of the facility is being assessed by instream monitoring.
A) The Draft Permit has inadequate monitoring.
Response: Frequency of monitoring and number of parameters that are being monitored are based
on results of the reasonable potential analysis (RPA) and requirements contained in the Federal and
State rules and regulations. If a parameter shows reasonable potential and requires a limit,
monitoring is generally at a monthly or quarterly frequency. If a parameter does not show
reasonable potential, monitoring might not be required. Monthly discharge monitoring reports
(DMRs) and priority pollutant scans (required with each permit renewal) are evaluated for RPA with
each renewal. The proposed monitoring frequencies will provide adequate information to conduct
RPA for the next permit renewal. The Division has a long term monitoring data for coal-fired
facilities' discharges and accumulated a statistically significant dataset for all typical pollutants
associated with the coal ash. This data set allows for an accurate characterization of the discharge
from ash ponds at the frequency prescribed in the permit. In addition, Duke submitted chemical
characterization of the wastewater in ash lagoons that demonstrates little variation in the pollutant
concentration at the different depth levels. Therefore, additional monitoring is not likely to provide
any additional useful information. In addition, the EPA has approved the proposed monitoring
frequency.
17. The proposed permit violates North Carolina groundwater rules.
Response: According to 15A NCAC 02L .0106 (e), Any person conducting or controlling an activity that is
conducted under the authority of a permit initially issued by the Department prior to December 30, 1983 pursuant to

G.S. 143-215.1 or G.S. 130A-294, and that results in an increase in concentration of a substance in excess of the
standards at or beyond the compliance boundary specified in the permit, shall.... (4) implement an approved corrective
action plan for restoration ofgmundwater quality at or beyond the compliance boundary, in accordance witb a schedule
establisbed by the Secretary.
This rule indicates current permits that exceed 02L standards have actions they must take while still
being permitted. This rule does not indicate these facilities cannot continue to be permitted;
however, it does require for the facility to take corrective action. Both the Coal Ash facilities at
Mayo and Roxboro Steam Plants are in this process. In addition, the Coal Ash Management Act
(CAMA) of 2013 directs each Coal Ash facility under 130A-309.211 to (a) provide a groundwater
assessment for any groundwater exceedances, and (b) provide a corrective plan to address
restoration of groundwater quality. Closure plans must be submitted no later than December 31,
2019, which must include .. provisions for completion of activities to restore groundwater... according to 02L
requirements. Once classifications are finalized, each impoundment, depending on their
classification, will be closed under options provided by 130A-309.214.
18. DEQ fails to exercise it's best professional judgement to establish BTA for impingement mortality
and entrainment under 316(b).
Response:: The Division is under time constraint to issue permits due to CAMA and the
requirement to close the ash ponds. The development of impingement and entrainment (IE) BAT
will take considerable time while at the same time the facility is developing studies to meet 316(b)
regulations for IE.
Sierra Club:
1. Permit fails to establish sufficient effluent limits. Permit allows Duke to continue to discharge
arsenic, mercury, selenium and other pollutants until 2023. The permit also allows the discharge of
bottom ash until 2021.
Response: The need for water quality based effluent permit limits is determined according to a
reasonable potential analysis (RPA). The RPA procedure utilized by the Division is in accordance
with EPA's regulation at 40 CFR 122.44(d)(1). Permit limits are added only if the results of the RPA
suggest potential for exceeding the water quality standards, and are not arbitrarily assigned. Outfall
002 is an internal outfall where water quality standards are not applicable as limits. The discharge to
waters of the state is outfall 003 where an RPA was conducted and limits implemented accordingly.
Monitoring for mercury, antimony and molybdenum was added for outfall 003. The RPA for outfall
006 was revised and limits were added for selenium.
2. The proposed deadlines for compliance with the new EGL are not justified.
Response: The extended deadlines for Compliance with the New Effluent Limitations have been
established in accordance with the 40 CFR 423. Duke provided justification for the compliance
schedule, which is well within authorized by the federal rule.
3. Draft permit fails to establish interim requirements for impingement and entrainment
Response: The Division is under time constraint to issue permits due to CAMA and the requirement
to close the ash ponds. The development of impingement and entrainment (IE) BAT will take
considerable time while at the same time the facility is developing studies to meet 316(b) regulations
for IE.

4. Draft permit illegally legitimize seeps.
Response: � 130A-309.210 of the Coal Ash Management Act (CAMA) of 2014 requires owners of
coal combustion residuals surface impoundments to identify and assess all discharges from the
impoundments and to implement corrective action to prevent unpermitted discharges from the
impoundments to the surface waters of the state. Identification of discharges includes engineered
channels designed or improved for the purpose of collecting water from the toe of the
impoundment (toe drains), as well as non -engineered seeps and weeps. One method of proposed
corrective action allowed under the Act is to make application for a National Pollutant Discharge
Elimination System (NPDES) permit amendment to bring the unpermitted discharge under permit
regulations. A Discharge Assessment Plan for the unpermitted discharges at the Roxboro Steam
Electric Station was submitted by Duke Energy to the Department on September 2014. The draft
permit requires the permittee to demonstrate that water quality standards in the receiving stream are
not contravened. This demonstration must be submitted to the Division no later than 180 days
from the effective date of the permit.
�130A-309.213 of the Act required the department to develop a proposed classification system for
all coal combustion residuals surface impoundments, including active and retired sites. 5130A-
309.214 requires owners of coal combustion residual surface impoundments to submit a proposed
closure plan for the Departments approval. High -risk impoundments shall be closed no later than
December 31, 2019, intermediate -risk impoundments shall be closed no later than December 31,
2024, and low -risk impoundments shall be closed no later than December 31, 2029.
5. Draft permit contains inadequate monitoring requirements.
Response: Frequency of monitoring and number of parameters that are being monitored are based
on results of the reasonable potential analysis (RPA) and requirements contained in the Federal and
State rules and regulations. If a parameter shows reasonable potential and requires a limit,
monitoring is generally at a monthly or quarterly frequency. If a parameter does not show
reasonable potential, monitoring might not be required. Monthly discharge monitoring reports
(DMRs) and priority pollutant scans (required with each permit renewal) are evaluated for RPA with
each renewal. The proposed monitoring frequencies will provide adequate information to conduct
RPA for the next permit renewal. The Division has a long term monitoring data for coal-fired
facilities' discharges and accumulated a statistically significant dataset for all typical pollutants
associated with the coal ash. This data set allows for an accurate characterization of the discharge
from ash ponds at the frequency prescribed in the permit. In addition, Duke submitted chemical
characterization of the wastewater in ash lagoons that demonstrates little variation in the pollutant
concentration at the different depth levels. Therefore, additional monitoring is not likely to provide
any additional useful information. In addition, the EPA has approved the proposed monitoring
frequency.
Clean Water for North Carolina:
Outfall 001 — outfall has no limits for most toxic metals likely to be present in seeps from coal ash.
Seeps should not become legal discharges. Monitoring should be twice a month.
Response: The need for water quality based effluent permit limits is determined according to a
reasonable potential analysis (RPA). The RPA procedure utilized by the Division is in accordance
with EPA's regulation at 40 CFR 122.44(d)(1). Permit limits are added only if the results of the RPA
suggest potential for exceeding the water quality standards, and are not arbitrarily assigned.

5 130A-309.210 of the Coal Ash Management Act (CAMA) of 2014 requires owners of coal
combustion residuals surface impoundments to identify and assess all discharges from the
impoundments and to implement corrective action to prevent unpermitted discharges from the
impoundments to the surface waters of the state. Identification of discharges includes engineered
channels designed or improved for the purpose of collecting water from the toe of the
impoundment (toe drains), as well as non -engineered seeps and weeps. One method of proposed
corrective action allowed under the Act is to make application for a National Pollutant Discharge
Elimination System (NPDES) permit amendment to bring the unpermitted discharge under permit
regulations. This approach was approved by the EPA.
Frequency of monitoring and number of parameters that are being monitored are based on results
of the reasonable potential analysis (RPA) and requirements contained in the Federal and State rules
and regulations. If a parameter shows reasonable potential and requires a limit, monitoring is
generally at a monthly or quarterly frequency. If a parameter does not show reasonable potential,
monitoring might not be required. Monthly discharge monitoring reports (DMRs) and priority
pollutant scans (required with each permit renewal) are evaluated for RPA with each renewal. The
proposed monitoring frequencies will provide adequate information to conduct RPA for the next
permit renewal.
2. Outfall 002 — limits are inadequate for ash pond discharge.
Response: Outfall 002 is an internal outfall where water quality standards are not applicable as limits.
It includes technology based limits and monitoring for pollutants present in coal ash. For both
decanting and dewatering phases the permit includes monitoring for pollutants of concern for coal
ash dewatering. Monitoring for arsenic, molybdenum, cadmium, chromium and total dissolved
solids were added to the ash pond decanting phase.
3. Outfall 003 — effluent monitoring parameters and monitoring frequency are inadequate. All
parameters should be limited and monitoring frequency should be monthly.
Response: The need for water quality based effluent permit limits is determined according to a
reasonable potential analysis (RPA). The RPA procedure utilized by the Division is in accordance
with EPA's regulation at 40 CFR 122.44(d)(1). Permit limits are added only if the results of the RPA
suggest potential for exceeding the water quality standards, and are not arbitrarily assigned. An RPA
was conducted for outfall 003 and limits implemented accordingly. The RPA has since been revised
a new limit for thallium established and monitoring for mercury, antimony and molybdenum were
added for outfall 003.
4. Outfall 005 - inadequate monitoring frequency and limits, 126 pollutants should be monitored
quarterly.
Response: The limits for outfall 005 are TBEL limits established by federal effluent guidelines and
meet all the requirements in 40 CFR 423.
5. Outfall 006 — inadequate effluent parameters and monitoring frequency.
Response: Limits for coal pile runoff are TBEL limits established by federal effluent guidelines and
meet all the requirements in 40 CFR 423. Additional parameters are added if present in the priority
pollutant scan. The RPA has since been revised and limits were added for selenium.
6. Outfalls 008 through 012 — insufficient parameters and inadequate monitoring frequency.

Response: Outfall 008 is a small domestic wastewater treatment system internal to the ash basin
then eventually to the discharge canal. The Division deems monitoring and sampling adequate for
this outfall. When the new system is constructed monitoring is quarterly for the first year to evaluate
performance. Limits for Outfalls 010 and 011 for the discharge of FGD treated wastewater are also
internal and limits have been established based on 40 CFR 423. The discharge of low volume wastes
under Outfall 012 includes effluent guideline limits and other parameters of concern.
7. Thermal Discharge — unjustifiable mixing zone, biological report should have more rigorous
requirements.
Response: The mixing zone was approved by the Division and the EPA. The biological monitoring
sampling plan follows approved procedures. These plans are revised by the Water Science Section
and modified to include additional requirements when appropriate.
Other Public Comments:
The division received 94 email comments during the public comment period objecting to the issuance of
the permit. Most of the comments oppose the discharge of coal ash pollutants to Hyco Lake, and
object to leaving the coal ash in unlined ponds. All the comments presented in emails have been
addressed in the responses to the comments from environmental groups in sections above.