HomeMy WebLinkAboutNCS000549_FINAL PERMIT Cover Letter_20150515A'741
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NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory
Governor
Mr. Harry K. Sideris
Senior Vice President
Environmental, Health, & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, NC 28202
Dear Mr. Sideris:
Donald R. van der Vaart
Secretary
May 15, 2015
Subject: NPDES Stormwater Permit Application
Riverbend Steam Station
Permit Number NCS000549
Gaston County
In response to your application for coverage under NPDES stormwater permit NCS000549, the Division of
Energy, Mineral, and Land Resources (Division or DEMLR) is forwarding herewith the subject state - NPDES
permit. This permit is issued pursuant to the requirements of North Carolina General Statute 143-215 .1 and
the Memorandum of Agreement between North Carolina and the U.S. Environmental Protection Agency
dated October 15, 2007 (or as subsequently amended).
This final permit includes the following changes from the draft permit posted on our website on
March 6, 2015:
Outfall SWO01 has been removed (being already included in the facility's wastewater permit).
Text has been added for monitoring requirements for SW010, SW011, SWO12 to allow exemption
from monitoring if the company demonstrates no industrial activities or materials/equipment
storage associated with this steam station site occur here, upon concurrence from NC DENR.
The Sample Location column in Part II, Table 9 has been revised to clarify that sampling is required
only from SWO14A and SWO14B (PVC pipe outfalls in the septic tank area that were not identified in
the application but were observed by NC DENR during a site visit in June 2014)—not SW014. This
is not a change from the proposed requirements but is now more specifically identified.
Thank you for your comments submitted on May 5, 2015. Please see our responses below:
1. Duke Energy requested removal of stormwater outfall SWO01 because it has since been included
in NPDES Wastewater Permit NC0004961. We concur and have removed this outfall in the final
permit.
2. Duke Energy requested a footnote be added to outfalls SW003A, SW013, SWO15, SW016, and
SWO17 that requires monitoring for Boron and Priority Pollutant Metals only if coal or coal ash is
transported through the drainage area.
Division of Energy, Mineral, and Land Resources
Energy Section • Geological Survey Section • Land Quality Section
1612 Mail Service Center, Raleigh, North Carolina 27699-1612.919-707-9200 / FAX: 919-715-8801
512 North Salisbury Street, Raleigh, North Carolina 27604 • Internet: http://portal.ncdenr.org/web/Irl
An Equal Opportunity 1 Affirmative Action Employer— 50% Recycled 110% Post Consumer Paper
Mr. Harry Sideris
May 15, 2015
Page 2 of 4
This footnote was incorporated for outfalls where the drainage areas were more definitive. For the
outfalls listed above, the drainage areas and potential pollutant sources were ambiguous:
• SWO03A was not included in the original application but was observed during a site visit by NC
DENR, and therefore added to the draft permit—drainage area undetermined;
• SWO13 was noted as "Abandoned" in Duke Energy's permit application last year, but then was
slated "to be grout -filled and abandoned" in correspondence from the company in December
2014—drainage area undetermined;
• SW015, SW016, and SWO17 were not included in the permit application but were later
identified during an engineering field evaluation as a 12" CMP, 24" CMP, and 30" RCP "to be
grout filled and abandoned" in the company's December 2014 letter—drainage areas
undetermined. We numbered these outfalls in sequence after the first 14 and included them in
the draft permit.
The company has asserted that these outfalls are not expected to be impacted by coal or coal combustion
residuals during decommissioning activities (December 2014 correspondence). However, with little
information about the contributing drainage area, DEMLR feels a comprehensive suite of parameters is
appropriate to characterize the discharge. The company will only need to monitor these outfalls until
they are removed or abandoned.
3. Duke Energy requested that the monitoring requirements for outfalls SW010, SW011, and
SWO12 be removed from the permit because they are associated with the Lark Maintenance
Facility and not part of the industrial activities that occur at Riverbend.
We acknowledge that NC DENR's response to the company's comments on this topic in March 2012 on a
previous draft permit agreed with this rationale. We have since developed a permit to include a more
comprehensive list of stormwater outfalls at the site based on more recent application information from
you, site visits by NC DENR during the past year, and a re-evaluation of former circumstances. The most
recent information provided on May 15, 2014 (the addendum updating the original application
submittal in 2011, Form 2F Supplemental Information) did not specify what kind of maintenance was
performed at the Lark Maintenance Facility. The "General Site Information" section of that document
noted that the "Lark Maintenance Garage is considered part of the Riverbend Steam Station as well, and
is located along the facility western property boundary."
We realize activities, material and equipment storage, and/or management arrangements may have
changed since last year, or may not have been detailed completely in the supplemental document. To
address the company's concern, we added the following language above Table 7 in Part II of the permit:
"If the permittee demonstrates that this Maintenance Facility does not perform any industrial activities
or store materials or equipment related to Riverbend Steam Station, these outfalls shall be exempt from
monitoring upon concurrence by NC DENR."
4. Duke Energy requested that monitoring requirements for outfalls SWO02, SW003, and SWO06 be
removed from the permit because these outfalls are inaccessible, and because there are no
collection points between SWO02 or SWO06 and their respective oil trap tanks (preventing
representative samples).
We note that the company provided stormwater discharge samples for these outfalls from May 2014 (all
three outfalls) and July 2014 (SWO02). We understand this does not necessarily mean the outfalls are
routinely accessible, but it does demonstrate sampling is possible. We understand the company's
concerns about safety and secure access to outfalls, and we fully support precautions to ensure
accessibility is safe and appropriate for your employees. To that end, it is generally acceptable to sample
at the nearest, safely accessible location upstream of a stormwater outfall when necessary to obtain a
sample. We also note in Duke Energy's response letter from August 11, 2011 that you referenced, the
company proposed constructing safe access to SWO02 and SWO03 (page 2).
Mr. Harry Sideris
May 15, 2015
Page 3 of 4
Further, the company may wish to pursue a Representative Outfall Status (ROS) designation for one or
more of these outfalls to address its concerns. ROS would reduce which outfalls at the site must be
sampled. DEMLR handles ROS designation outside of the permit because ROS is subject to change if
activities or other circumstances change. This procedure allows designations of and any changes to ROS
to be handled more expeditiously, without reopening the permit for modification. Please coordinate
with the Mooresville Regional Office if you wish to pursue ROS designation for any stormwater outfalls.
5. Duke Energy requested monitoring requirements for Outfalls SW014, SWO14A, and SWO14B be
removed from the permit. The draft permit proposed monitoring for outfalls `other than SW014" (no
monitoring for SW014) but was not as clear as it could be. We revised the permit to be more specific.
According to Duke Energy's letter dated July 14, 2014, SWO14A and SWO14B are pipes associated with
an old sanitary sand filter system and were supposedly abandoned in the 1990s. If these pipes never
discharge, monitoring requirements do not apply. However, there was some uncertainty about whether
the source and/or abandonment could be confirmed. Until then, any discharges must be monitored.
6. Duke Energy requested that all outfalls to be abandoned be referenced as one group in the
permit instead, and a timeframe to abandon them be established in the permit. We do not agree
this approach is the most appropriate. If unforeseen circumstances required changes to the timeline for
removal or abandonment of any of these pipes or outfalls, Duke Energy would have to apply for a permit
modification—particularly when there are so many (SW003A, SW007, SW007A, SW013, SW014,
SWO14A, SWO14B, SW015, SW016, and SW017). The permit requires written notification to DEMLR
that confirms the potential for stormwater discharges has ceased in order to suspend monitoring
requirements and should not be unduly burdensome on the permittee (even less so if timelines change).
Failure to complete the monitoring as required is a violation of the permit and any permit noncompliance
constitutes a violation of the Clean Water Act. Reference Part III, Section A, Item 2 "Duty to Comply", Item 9
"Penalties for Tampering" and Item 10 "Penalties for Falsification of Reports" of your permit for further
information.
If any parts, measurement frequencies or sampling requirements contained in this permit are unacceptable
to you, you have the right to an adjudicatory hearing upon written request within thirty (3 0) days following
receipt of this letter. This request must be in the form of a written petition, conforming to Chapter 150B of
the North Carolina General Statutes, and filed with the Office of Administrative Hearings, Post Office Drawer
27447, Raleigh, North Carolina 27611-7447. Unless such demand is made, this decision shall be final and
binding.
Per the requirements of the Catawba Riparian Buffer Rule, all stormwater drainage from portions of this site
that have been constructed after June 30, 2001 must be discharged through a correctly designed level
spreader or another device that meets diffuse flow requirements per 15A NCAC 213.0243. Diffuse flow
requirements are described in Chapter 8 of the North Carolina Stormwater BMP Manual, available at:
htt://nortal.ncdenr.org/web/lr/bmp-manual.
Please take notice this permit is not transferable. Part II1, B.2. addresses the requirements to be followed in
case of change in ownership or control of this discharge. This permit does not affect the legal requirements
to obtain other permits which may be required by the Division of Energy, Mineral, and Land Resources, or
permits required by the Division of Water Resources, Coastal Area Management Act or any other federal or
local governmental permit that may be required.
If you have any questions or comments concerning this permit, contact Bethany Georgoulias at (919) 807-
6372 or at bethany.georgouliasOncdenr.gov.
Mr. Harry Sideris
May 15, 2015
Page 4 of 4
Sincerely,
Original signed by Tracy E. Davis
Tracy E. Davis, PE, CPM, Director
Division of Energy, Mineral, and Land Resources
cc: Mooresville Regional Office, DEMLR Land Quality Section
Sam Sampath, Ph.D., EPA Region IV, 61 Forsyth Street, Atlanta, GA 30303
Stormwater Permitting Program
DWR Central Files
Attachments: NCS000549