Riverbend Steam Station (4)

�0�'/e- r4-
May 1, 2012
Mr Matt Matthews
Section Chief
Surface Water Protection Section
North Carolina Department of Environment
and Natural Resources
1617 Mail Service Center
Raleigh, NC 27699 -1617
Subject Duke Energy Carolinas, LLC
Stormwater Permitting Proposal
Dear Mr Matthews
526 South Church St
Charlotte, NC 28202
Mailing Addfess
PO Box 1006
Mad Code EC13K
Charlotte, NC 28201 -1006
704 382 6240 fax
ECEHJE'0
iF M 2012
__J
DENR - WATER OUALITY
SURFACE WATER PROTECTION SECTION !
As a follow up to our recent discussions and meetings regarding draft DWQ stormwater permits,
Duke Energy proposes the following stormwater permitting protocol for our steam electric
facilities located in North Carolina-
a Duke Energy supports permit requirements for semi- annual quantitative monitoring for
TSS and pH for any stormwater outfalls that discharge runoff from coal storage piles
directly into waters of the state as required under effluent guidelines At the present time,
Duke has no such outfalls at our facilities. All stormwater runoff from our coal storage
piles is directed into coal ash ponds that have NPDES discharge permits that include
appropriate monitoring requirements
b As a general indicator for our system of coal -fired power plants, Duke supports semi-
annual quantitative monitoring for TSS and pH from representative outfalls at Plant Allen
and Riverbend. Representative outfalls to be monitored are SW005, SW008, SW011 and
SW015 (Plant Allen), and are SWO02 and SWO03 (Riverbend).
c Duke Energy supports permit requirements for semi- annual quantitative monitoring at
representative outfalls for any parameter associated with our operations if there is an in-
stream impairment for that parameter Monitoring will be discontinued following two
consecutive non - detect results
d Duke Energy cannot support monitoring for mercury at our stormwater outfalls based on a
303(d) listing that has been established without supporting fish tissue data Duke has
submitted comments on this issue previously The DWQ /DAQ point effort to establish a
TMDL for mercury has shown that the mercury in fish tissue is not a result of water
discharges, and has shown that air emissions from NC utilities are responsible for much
less than half of the mercury in NC surface waters This point effort has also shown that,
with the scheduled retirements and upgrades to our facilities, utility air emissions in NC
are appropriately controlled
www duke - energy com

Duke Energy supports semi- annual qualitative monitoring at representative outfalls for all
of our coal -fired power plants that have active NPDES ash basin discharge permits This
monitoring will involve characterizing collected samples for color, odor, clarity, presence of
floating solids, settled solids, suspended solids, foam, oil sheen, or other indications of
stormwater pollution Representative outfalls to be monitored are SW005, SW008,
SW011 and SW015 (Plant Allen), SWO02 and SWO03 (Riverbend), SWO03 and SWO07
(Marshall), and SW002, SWO05 and SW073 (Buck)
g Duke Energy supports development and implementation of stormwater pollution
prevention plans as drafted by DWQ with certain exceptions Duke Energy does not
support the requirement for a feasibility study, and does not support the requirement for a.
written rationale for installation and implementation of BMPs
Duke Energy believes that stormwater permits with these conditions are consistent with general
permits for steam electric facilities in other states, and are appropriate and reasonable given the
substantial data available on the health of receiving waters and the biological conditions where
our facilities have operated for decades Such terms as proposed by Duke Energy are sufficient
to meet regulatory requirements
Duke Energy would also support DWQ development of a NPDES General Permit for steam
electric facilities provided that it adheres to the conditions expressed above Duke Energy
believes that this approach could be efficient and cost effective for both DWQ and permittees,
especially during the permit renewal process
Please contact Mark McGary @duke- energy com or at 704 - 634 -7098 if you have any questions
or need any additional information
Sincerely,
Mark McGary, P E
Environmental, Health & Safety