NC0039586_Draft Permit Comments_20160816

(' DUKE
ENERGY®
AUG 0 8-2016.
Serial: HNP -16-063
Ms. Teresa Rodriguez, Environmental Engineer
NPDES Complex Permitting Unit
NC DEQ Division of Water Resources
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Subject: Harris Nuclear Plant
Comments Regarding Draft NPDES Permit No. NCO039586
Wake County
Dear Ms. Rodriguez:
Benjamin C. Waldrep
Vice President
Harris Nuclear Plant
5413 Shearon Harris Road
New Hill, NC 27562-9300
919.362.2502
RECEIVEMCDEQ/DWR
AUG 16 2016
Water Quality
Permitting Section
In accordance with your letter dated July 13, 2016, Duke Energy staff have reviewed the
proposed draft permit and the accompanying Fact Sheet and offer the following comments in
response to your bulleted draft permit proposals:
Draft Permit Proposal:
• pH limits of 6 to 9 S.U. were added to ouffalls 001, 004, and 005 as required per 40 CFR
423.12 (b) (1).
Comments:
Duke Energy requests that the Division remove pH monitoring and limits from outfalls 001, 003,
004, and 005, all of which are internal outfalls that discharge to outfall 006. (In addition to the
three outfalls in this bullet, pH limits were also added to outfall 003.) Limitations for pH are more
appropriate for outfalls discharging to surface waters, for the following reasons:
1. 40 CFR 423.12(b)(1) requires pH limits only on outfalls discharging to surface waters
The requirements of 40 CFR 423.12(b)(1) read as follows:
(1) The pH of all discharges, except once through cooling water, shall be within the range of
6.0-9.0.
The definition of "discharge" in 40 CFR 122 reads as follows:
Discharge when used without qualification means the "discharge of a pollutant."
Page 1

Discharge of a pollutant means:
(a) Any addition of any `pollutant' or combination of pollutants to "waters of the United States"
from any `point source, "or
(b) Any addition of any pollutant or combination of pollutants to the waters of the `contiguous
zone" or the ocean from any point source other than a vessel or other floating craft which is
being used as a means of transportation.
The phrasing indicated in 40 CFR 423.12(b)(1) means a discharge to waters of the United
States and thus would be appropriate for this permit for Ouffall 006. The remaining BPT limits in
this section refer to a pollutant being discharged "from" or "in" a specific source and thus are
appropriately applied to internal ouffalls.
2. EPA guidance recommends against use of PH limits on internal outfalls
The pH limits of 40 CFR 423.12(b)(1) were proposed and adopted in the original 1974 Effluent
Limitations Guidelines for the Steam Electric Industry (ELG) as best practical control technology
(BPT). In the 1980 Development Document for the proposed revisions to the ELG, EPA
provided a discussion of the application of the effluent limitations guidelines presented in the
1974 Development Document that accompanied the rulemaking. In this discussion, EPA
specifically stated "In -plant dilution is permitted to achieve pH limitations."' This interpretation is
also explained in several guidance letters from EPA included in Attachment A and this approach
has been used in recent permits issued by EPA. A summary of these letters and their
application is as follows:
March 10, 1976, Letter from USEPA to Philadelphia Electric Company states:
".. waste streams could be combined with cooling water for the sole purpose o1 pH
neutralization, as long as the final discharge was in the range of 6-9."
October 18, 1985, Letter from USEPA to New York State Department of Environmental
Conservation states:
"...the pH limitation per 423 applies at the "end of pipe" discharge to surface waters when
the wastewater discharges contains low volume waste that is commingled with once -through
cooling water."
February 24, 1986, Letter from National Expert Steam/Electric Region IV (Charles Kaplan) to
Environmental Engineer Region 2 (Dit Fai Chung) states:
11
... pH limitations for the comingled stream are applicable at the combined discharge point
to water of the U.S."
March 21, 1986, Letter from USEPA to Regional Permit Chiefs, State Directors, states:
"the pH limitations for the low volume waste (6.0 — 9.0 range) may be applied after
combination of once -through cooling, provided that monitoring is prior to discharge to
Waters of the United States."
' 1980 Dev. Doc. at 470
Page 2

USEPA, New England - Region I Fact Sheet Draft NPDES Permit for Mirant Canal, LLC, states:
"Monitoring for pH at the internal outfalls 010, 011, and 012 is not necessary as explained in
EPA's March 21, 1986, Memorandum from Charles Kaplan, EPA's National Steam
Electric/Water Expert, to Regional Permit Branch Chiefs and State Directors. Using dilution
to accomplish the neutralization of pH is preferable to adding chemicals."
3. Recent decisions by EPA in the ELG Rule demonstrate that pH monitoring on internal
outfalls is unnecessary
In the recently finalized revisions to the ELG, much emphasis was placed on demonstrating
compliance prior to the mixing of waste streams. EPA proposed that dischargers
demonstrate compliance with the proposed effluent limitations and standards applicable to a
particular waste stream prior to mixing the treated waste stream with other waste streams,
which could require internal outfalls; however, EPA explicitly stated the provision would
apply to all effluent limits "except pH .,,2 The exemption of pH provides justification that EPA's
policy of not setting internal limits for pH still applies. EPA opted to not finalize the rule
requiring internal outfalls but chose to recommend conducting a combined waste stream
formula (CWF) or building block approach to determine whether internal outfalls are
necessary or apply appropriate limits at the final ouff all. The purpose of this action was to
ensure the pollutant loading (i.e. mass) is reduced and not merely "masked" through dilution
when concentration limits are applied. However, pH is not a mass based parameter and is
not associated with pollutant loading. Furthermore, Section 14 of the Final Technical
Development Document for the revisions to the ELG provides illustrations of compliance
points under different pre- and post -rule scenarios. In all scenarios, BPT limits, which
include pH, are depicted as applying at the final outfall. Even though only one of the waste
streams proposed for revision and none of the waste streams revised in the final rule apply
to HNP, the fact that EPA specifically stated effluent limits at internal outfalls would not
include pH supports that limits for pH should be applied only at the final outfall.
4. Limits on pH at internal outfalls are not necessary to protect the environment
Furthermore, there is no environmental justification for establishing pH limits at the internal
ouffalls. As stated above, pH is not a parameter associated with pollutant loadings, but
rather is a scale for expressing the acidity or alkalinity of a solution. The preferred treatment
is neutralization with a buffer solution. By utilizing mixing with other waste streams,
neutralization can be accomplished without chemical addition or at least minimizing
chemical addition at the final outfall. As stated in the documents discussed above (February
24, 1986, Letter and USEPA Region 1 Fact Sheet for the Mirant Canal, LLC, NPDES
Permit), using dilution to accomplish the neutralization of pH is preferable to adding
chemicals.
Draft Permit Proposal:
Effluent and Monitoring requirements for outfall 002 were modified to reflect the
expansion of the wastewater treatment system. Special Condition A. (18) was added to
the permit to allow for the transfer of wastewater between the two domestic WWTPs.
Comments:
Duke Energy agrees with this approach.
2 78 Fed. Re& 34523 (7 June 2013) .
Page 3

Draft Permit Proposal:
• The NC 2007-2014 Water Quality Standard (WQS) Triennial Review was approved by
the NC Environmental Management Commission (EMC) on November 13, 2014. The US
EPA subsequently approved the WQS revisions on April 6, 2016 with some exceptions,
one being the disapproval of action level policy for permitting silver, copper and zinc. In
addition, the total metal aquatic life criteria for chromium, iron, and manganese were
deleted from the NC water quality standards rules.
The NC Division of Water Resources NPDES Permitting Unit is required to implement the
new dissolved metal standards in all permits public noticed after April 6, 2016. The new
standards for most metals include acute standards. Further, the freshwater standards for
several metals are expressed as the dissolved form of the metals, and seven metals have
hardness -dependent equations. A reasonable potential analysis (RPA) was performed
utilizing the new standards. As a result of the RPA limits for copper and zinc were added
to outfall 006. These limits become effective five years after issuance of the permit. A
schedule of compliance is included to allow the facility to perform studies and implement
corrective actions. See Special Condition A. (9) Schedule of Compliance.
Comments:
Duke Energy understands that the Division must evaluate applicability of newly adopted water
quality standards but does not agree that final limits should be included in this iteration of the
permit. Because these limits have not been included in earlier permits, the limited information
available about these parameters is not sufficient to justify a determination that the limits are
necessary to meet water quality standards in Harris Lake.
The proposed effluent limits are based upon very conservative assumptions and default values
which warrant development of site specific characterization information. The need for specific
effluent limits for Total Copper and Total Zinc is contradicted by the fact that the discharge has
been in place for many years and Harris Lake is not impaired for Copper and Zinc based on
data collected by the Division and Duke Energy.
Duke Energy believes the NPDES permit should require a study to evaluate the need for
effluent limits, which should be inserted in the permit as a replacement for the corrective action
plan:
"A study of the necessity of limits for copper and zinc shall be conducted and may
include submission of additional effluent and receiving water data, mixing zone analyses,
and/or site specific studies to indicate whether effluent limitations for total copper and
total zinc are necessary to protect the dissolved water quality standards. The adopted
water quality standards define the criteria as the hardness based criterion times a Water
Effect Ratio (W ER) and also indicate that alternative site specific standards can be
developed. Methods for conducting site specific studies including development of WER
will be reviewed with the Division.
"Upon review and approval of supplemental data, analyses, and/or site-specific studies,
the Division agrees to base development of effluent limitations for total copper and total
zinc based on the results of these studies and modify this NPDES permit accordingly."
Furthermore, EPA's disapproval of the action level classification of copper and zinc did not
remove those provisions from the North Carolina Administrative Code. EPA recommended that
NCDEQ remove these provisions during the next rulemaking. By postponing the limits until a
study has been completed, the Division will also have time to undertake a rulemaking, which
would clarify the authority for the new parameters.
Page 4

If the Division includes the Total Copper and Total Zinc limits, the following language should be
added to Part I (A)(9) — Schedule of Compliance:
`The Corrective Action Plan may include submission of additional effluent and receiving
water data, mixing zone analyses, and/or site specific studies to indicate that alternative
effluent limitations for total copper and total zinc are appropriate to achieve the dissolved
water quality criteria. The adopted water quality standards define the criteria as the
hardness based criterion times a Water Effect Ratio (WER) and also indicate alternative
site specific standards can be developed. Methods for conducting site specific studies
including development of WEIR will be reviewed with the Division.
"Upon review and approval of supplemental data, analyses, and/or site-specific studies,
the Division agrees to base development of effluent limitations for total copper and total
zinc based on the results of these studies and modify this NPDES permit accordingly."
Draft Permit Proposal:
• As a result of the RPA, monitoring for total nickel, total iron and total manganese were
removed from the monitoring requirements for outfall 001.
Comments:
Duke Energy agrees with this approach.
Draft Permit Proposal:
• Flow monitoring was added to outfall 006. Flow is a monitoring requirement for all
discharges per 15A NCAC 026.0505.
Comments:
Duke Energy agrees with this approach and recommends the flow units for monitoring be
specified as Million Gallons per Day (MGD).
Draft Permit Proposal:
• Special Condition A. (17) was added to the permit regarding the submittal of all the required
information under 40 CFR 125.95 with the next permit application.
Comments:
Duke Energy agrees with this approach.
Draft Permit Proposal:
• The stormwater requirements included in Special Condition A. (20) will expire when the
Division of Energy, Minerals and Land Resources issues the individual stormwater permit for
this facility.
Comments:
Duke Energy agrees with this approach.
Draft Permit Proposal:
• A special condition was added to your permit including requirements for electronic reporting.
Proposed federal regulations require electronic submittal of all discharge monitoring reports
(DMRs) and specify that, 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
Page 5

implementation. The requirement to begin reporting discharge monitoring data electronically
using the NC DWR's Electronic Discharge Monitoring Report (eDMR) internet application
has been added to your NPDES permit. [See Special Condition A. (19)] For information on
eDMR, registering for eDMR and obtaining an eDMR user account, please visit the following
web page: http://portal.ncdenr.orp/web/wq/admin/bop/ipu/edmr.
For information on EPA's proposed NPDES Electronic Reporting Rule, please visit the
following web site: http://www2.epa.gov/compliance/proposed-npdes-electronic-reporting-
rule.
Comments:
Duke Energy agrees with this approach.
Draft Permit Proposal:
• The following special conditions were added to the permit to be consistent with other Duke
Energy permits: A. (10) Biocides, A. (11) Chemical Cleaning Wastes, A. (12) Combined
Waste Streams, A. (13) Federal Insecticide, Fungicide and Rodenticide Act, A. (14) PCB
Compounds, A. (15) Radioactive Material, and A. (16) Toxicity Reopener.
Comments:
Duke Energy agrees with this approach.
Our review also identified several other items for which we would like to offer the following
comments:
1. Relative to Total Residual Chlorine monitoring requirements for Outfall 002, this sanitary
waste treatment system functions predominately with a ultraviolet (UV) disinfection system.
The sodium hypochlorite system is rarely used and is maintained for backup purposes.
Duke Energy requests that a footnote for Total Residual Chlorine in Outfall 002 be added to
read:
"Total Residual Chlorine is only required to be monitored and reported if chlorine is added to
the sanitary treatment system for disinfection purposes."
2. A special condition in the previous NPDES permit (Part Il, Special Condition No. 2)
regarding the Auxiliary Reservoir was removed from the proposed draft permit. This
condition should be reinstated in the final permit:
"In order to ensure that the auxiliary reservoir is available for its designated use at all times,
the permittee may circulate heated water through the auxiliary reservoir to prevent ice
formation at any time that the surface water temperature is below 35°F provided that the
surface water temperature in the auxiliary reservoir is not raised more than 5°F above
ambient temperature and in no case is raised to more than 40°F. Emergency Service Water
may be discharged to the auxiliary reservoir as required for operation of nuclear safety
systems and testing."
3. Special Condition A. (15) references McGuire Nuclear Station and should be corrected to
read "Harris Nuclear Plant."
Page 6

4. On the "Supplement to Permit Cover Sheet," the description of the 0.02 MGD wastewater
treatment facility should be revised to remove the following components:
a. Holding tanks; and
b. Comminutor.
These pieces of equipment are no longer in service and are not necessary to meet the
performance requirements associated with Outfall 007.
5. On Page 2 of the "Fact Sheet for NPDES Permit Development," Outfall Description for
Outfall 005, the following description clarification is suggested:
Radwaste treatment system. Treatment for potential radioactive liquids. The waste streams
are collected in tanks and sampled prior to selecting treatment. Radwaste is treated by a
Modular Fluidized Transfer Demineralization SystemM( FTDS). Radiological treatment
processes and components are modified as necessary to achieve desired treatment in
compliance with Nuclear Regulatory Commission regulations. If not radioactive, the wastes
are routed to the low volume waste treatment system.
6. On Page 2 of the "Fact Sheet for NPDES Permit Development," Outfall Description for
Outfall 007, the reference to "radiological wastes from cleaning lab glassware" should be
removed since cleaning of such radiological glassware has been discontinued at the Harris
Energy & Environmental Center.
If you have any questions or wish to discuss this matter further, please do not hesitate to
contact Mr. Bob Wilson, Harris Nuclear Plant Environmental Coordinator, at 919-362-2444.
I certify, under penalty of law, that this document and all attachments were prepared under my
direct supervision in accordance with a system designed to assure that qualified personnel
properly gather and evaluate the information submitted. Based upon my inquiry of the person or
persons who manage the system, or those persons directly responsible for gathering the
information, the information submitted is, to the best of my knowledge and belief, true, accurate,
and complete. I am aware that there are significant penalties for submitting false information,
including the possibility of fines and imprisonment for knowing violations.
Sincerely,
e,
Benjamin C. Wal ep, Site Vice President
Harris Nuclear Plant
Duke Energy Progress, LLC
Enclosure
cc: Mr. Danny Smith, NC DEQ DWR Raleigh Regional Office
Mr. Bob Wilson, Site Environmental Coordinator, Harris Nuclear Plant
Mr. Don Safrit, Senior Environmental Specialist, Permitting and Compliance, Carolinas
Page 7

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Documents Regarding Steam Electric pH Limitations
(18 total pages)

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Memorandums on Steam Electric pH Limitations
Excerpts from US EPA 1980 Steam Electric Point Source Category Development Document
(Highlights /Emphasis Added)

to ash pond effluents indicate effective removal of certain trace
metals, but more studies are necessary to confirm these results.
(b) NSPS
For the same reasons that EPA is not proposing any requirements beyond
BPT for existing sources, EPA is proposing to withdraw the current
NSPS requirement of 20 times recycle and substitute the basic BPT
requirement in its place. Unlike dry fly ash handling systems for new
sources (which are no more costly than other fly as handling systems)
a recycle system for bottom ash is substantially more expensive than
other bottom ash handling systems.
(c) PSES and PSNS
The proposed PSES and PSNS do not restrict the discharge of any
pollutants from this wastewater source. The costs of controlling
priority inorganic pollutants and the low levels of pollutants
detected do not warrant the imposition of effluent standards for this
waste stream at this time.
E. Metal Cleaning Wastes
This document supercedes all previous memoranda on effluent limi-
tations guidelines regarding the definition of metal cleaning wastes.
Metal cleaning wastes include boiler tube cleaning waste, air
preheater wash water and fireside wash water, with or without the use
of chemicals during the cleaning process.
The limitations for iron and copper of 1 mg/1 will not be changed.
For those cases where chelating or complexing agents are used in the
cleaning process, the treatment technology scheme may need to be
altered. Lime treatment of these chelated wastes, together with air
preheater and fireside wash water (at the proper ratio), will result
in the achievement of the 1.0 mg/1 limitation. An alternate
precipitation scheme using sulfide will also achieve the 1.0 mg/1
limit.
F. Low -Volume Wastes
The best practicable technology currently available is found to be
adequate for control and is being defined as best available technology
economically achievable. Boiler blowdown, which is currently
considered as a separate waste category, is required to be treated for
iron and copper. In reexamination of the waste characteristics
information, boiler blowdown is now redefined as low-volume waste and,
therefore, is no longer subject to the iron and copper limitations.
Application of Effluent Limitations Guidelines and Standards
A discussion of the application of the effluent limitations guidelines
was presented in the 1974 Development Document (1). Certain aspects
relating to the implementation of the original guidelines and
MIM

4
recommended revisions are discussed below. In -plant dilution is
permitted to achieve pH limitations. Consolidation of waste streams
to a centralized treatment system is permitted and encouraged. The
quantity of pollutant permitted to be discharged, however, is not ,
always equal to the total flow times the effluent limitations
guidelines. It would equal the effluent limitations guidelines times
total flow only if all the raw waste streams contributing to the
central treatment system have waste characteristics which exceed the
guidelines. For cases where the dilution ratio would be so great that
the analytical method is not accurate enough to distinguish the '
difference (such as low volume wastes containing oil and grease
exceeding 15 mg/l are discharged to ash ponds), monitoring at the
point prior to mixing (or dilution) would be required. The same
analogy can be used for any stream and any pollutant.
470

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Memorandums on Steam Electric pH Limitations
March 10, 1976 Letter from USEPA to Philadelphia Electric Company
(Highlights / Emphasis Added)

t
wra
Y
A
i
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION III
6TH AND WALNUT STREETS
PHILADELPHIA. PENNSYLVANIA 19106
In reply refer to
3EN21 J. H. LONG
March 10. 1976
i!7C
Mr. James long t
Power Plant Services Section 4••;•
Philadelphia Electric Company \1
2301 Market Street
Philadelphia, Pennsylvania 19101
Dear lir. long:
This is in response to your second progress report submitted February 10,
1976 for the Chastdr Generating Station (PA 0011614), in which you propose to d:
charge boiler blovdown, zeolite softener regenerates, and evaporator blwdovn tc
the receiving stream without pH neutralization. Please be advised that
4007R Part 423.32(b)(1) requires the pH of all discharges from pwar plants
(except once -through cooling water) to be in, the; range of 6 - 9. Economics
were considered prior to the development of the final guideline limitations,
therefore the expense you have cited as being associated with neutralizing them
effluent streams is not a valid argument against_ treatment.
A policy decision was made during the -EPA -PEA meeting in Washington, D.C.
that may influence your situation with respect io neutralizing these effluent
streams. It was decided that viete ntreama could be combined with cooling water,
-. 9:
menta.
not
0
I trust this will enable you to complete your treatment plans. If there
are any questions, please don't hesitate to contact me at 215 597-3689.
S1 erel r
y /y/ours
Bruce P.Smith
Delmarva -D.C. Section

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NC0039586
US EPA Memorandums on Steam Electric pH Limitations
October 18, 1985 Letter from USEPA to New York State Department of Environmental
Conservation
(Highlights /Emphasis Added)

SENT BY:ENV AFFPIRS. F : 2-22-95 7:36PAM : 5347 917888218:# 2
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WABMINGTON, D.C. 20400
Mr. Louis Canzieni
New York State
Department of Environmental
Conservation
Room 6126
Two World Trade Center .
New York, NY 10047
Deer Mr. Canziani:
This is to confirm our recent conversation regarding
effluent limitations guidelines for the steam electric power
industry (40 CFR Part 423).
In my letter of June 22, 1984 to Ms. Ursula Basch of
your office, I summarized the applicability of the steam
electric regulation pH linitation as applicable to low volume
waste streams when such wastewaters are commingled with
(once -through) cooling waters. The interpretation that I
provided was not in accord with prior information and lnstruc-
tions provided to EPA and State permitting authorities on
this subject.
The pH limitation per Part 423 applies at the "end -of -
pipe" discharge to surface waters when the wastewater discharge
contains low volume wastewater that is commingled' with once -
through cooling water. However, the intent of Part. 423 is
also that the total suspended solids and oil and grease
limitations appllcable..to low volume waste streams be applied
to the low volume 'waste component of such a combined discharge
prior to commingling of the individual waste streams.
I apologize for any confusion in permit development or
delays in permit issuance that may have occurred in this
matter. If you have any further questions, please contact me
at [phone].
Siimearely.
_�.�+.+s...es
Dennis Ruddy'
Project Officer
Industrial Technology Division

6NII EO STATES ENVIRONMENTAL vROTECTION AGENCY 4,
Ms. Ursula Basch
New York State
Department of Environmental
Conservation
Room 6126
2 World Trade Center
New York, New York 10047
Dear Ms. Basch:
This is in response to your question= eluri.ng cur
discussion on June 21 regarding the effluent limitations
guidelines for the steam. electric industry (40 CFR Part 423),
Te pit limitation to low volume waste streams
is int ded to .q
reuir-e "that low volume waste streams be
treated, as necessary, to comply with the pH limitation prior
to discharge. Furthermore, the basis for compliance with the
PH limitation is not buffering or dilution provided by cooling
waters or other waste streams which are commingled with low
volume wastes.
I trust that this information is responsive to your
questions. Please call me if you have any further questions.
(202-392-7165)
Sincerely,
( V
Dennis Ruddy
Project Officer_
Rffluent Guidelines Di:•isicn

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Memorandums on Steam Electric pH Limitations
February 24, 1986 Letter from National Expert Steam/Electric Region IV (Charles Kaplan) to
Environmental Engineer Region 2 (Dit Fai Chung)
(Highlights / Emphasis Added)

" uNITEO STATES ENVIRONMENTAL PROTECTION AGENCY
+E: February 24, 1986
rtcT: Steam Electric Generating Point Source Guidelines'(40 CFR Part 423)
PH Dtmttatioms For Low volume Wastes 0®irgled with Once Through Cooling slater
rww: National Expert, Steam Electric/Water
Region IV. (4W4 -FP):
1M Dit Fal Qu*, Environmental Sgineer
' Region 3I
ugh:., Mr. Geoffry Grubbs (E+i-336)
Oda Techni 61 Support Braacit
ought .ilc.. Denis (M -552A) ;
Project Manages, Steffi -.
ae
s+oe..,is:,e'�to,the December 18, 1985, letter from New York State request -
b*, faitill r a41kifiaation of.the subject guidelines beyond that provided by the
October i8_, 1985'.setter frm`Mr. Denis Ruddy At issue is whether 40 CER Parc
423•.requi res .46 _n t,ea rsrtira ;to be applied . for a low volume waste stream. prior
to:combination with core through cooling water.
I aiways bees?. my inB .that where low volume wastes .from a steam
electrlr ]power ,punt Are commingled .with. nice . through cooling water prior to
disciSaxgelto w sof tpe U S., pH limitations for the caomingied stream are
applicable,st the combined died=
'..app to waters of the U.S.' Limitations
for, ottroer.::pollmits, hocgevei, er+e•Applicable prior to combination.
Fievisicos;oi`•40 i423.12(b)(1) require 'The pA of all discharges, except
ftir,aooe thibc a cook water, shall be: in the_ range of 6.0 'to 9'.0." .Oda
gaidelin? s,to be. applied at rice'point'cf'ge to waters of the U.S. in
deve2opiag t9ae ReguiBtian, once tUsnagh opoling water .was, not subjectto a. PH
lim3itat3 occ dace the pH of intake ywater ` is - vikt uaily tamed bq . passage
L? _�yp Q {iiiVliy6ti�1•
1be has always anppCsed the use of dilution ace. a substitute for treatimetnt.
In't 'gM ro£ IS icowevet. enation a low volume wastes ..with' o o ,10 tough
ccblirg. wieter (another pleat taste) _produces. ch®ioal aaitrelizatieo, utilizing
;ambit intake water chemicals instead of added chemicals. HocoeVera ,tae' will
sunt coadaie,situaticns %J M 'dent water is pumped expressly for the purpose
'on'a case-by-case basis, other factors might allow/require that limitations be
applied at a point prior to combination. Some of these include:
T. Combination ofepeeifis low volume wastes with once through Cooling
water ;which il bemticipated to pnoduoe additional total suspended
solids, du: to the resulting •neutralization, sad which world eaeeed the
amonut allowed fon: the low volume wastes.
2. Failure to neutralise and settle the loo volume waste prior to combina-
tion would result in unacceptable quantities of hoary metals or other
ias3c polluutants being released. :.
3. iZEgTfromeuts of 316(b) which might limit the smount of cooling water
need.
IL.r.. lavas (a... 340

t _2_
BaYolo of NOW indicated instances where monitoring of the combined
disc 8e might be problematical. As previously noted, monitoring of a
dtbat 1Wis required prior to discharge to waters of the U.S. To
monitoring is impractical at the combined discharge point,
limitations and monitoring can 'be required prior to combination trader the
Provisions of 3122.45(h) [as renonberied by 49 RG&K9, September 26, 1984].
Fbi thelparposes of 122.45(h). the term "imprecticai" could include, but
would .not be limited . to. the inabiiity of the peimit tee to (1) ' manuall
e661le)et smpleas. (2) locate same g Wit, (3) locate analysis equipmerny'
Praperlgr.'service"apd•calibrate installed equipment,
it,111arolo also Indicated a situation where an underground diadwge ammel
of ib .. dammed_to.provide a.basin for neatralization Prior to ease to waters.
- rile..U.S. I. feel, diat such a method could, addeve compli�oe with the
guideline p •limitation "hissed. on .the discussion above. However. I wound
suggest mat the that
.permitting :authority consider at such a basin might be
8 3t'to"rapid, 310" of function due to filling by ambient intake solids.
1Jational Expert, Steelo Electric/Water

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Memorandums on Steam Electric pH Limitations
March 21, 1986 Letter from USEPA to Regional Permit Chiefs, State Directors
(Highlights / Emphasis Added)

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IV
345 COURTLANO STREET '
ATLANTA. GEORGIA 30185
March 21,.1986
' 4Fi1;;PF
] :Steam.Electric Generating Point Source Qudelines (40 CPR Part 423)
' •lam Limitations for LOW VolUme wastes CaQningled with_Onoe Through
Cooling Water ..g
Nat#enal Egpert"Stean ElectriC/Water
- r
b: r Regidna P�ennit Branch Chiefs
State Dizectors
u?,tttt�ed is a l�bruery,24. 1986 interpretation of 4,0 CFR 423.12(b) (I) as •it
' rebates to "p[i limYtatgons for low dol,ae.wastes which. are oaaningied, rijh
Faroe tfizotgh coaling wester. The pH limitations for _the lowwlume waste
4,d,
1r,bo'9'JO range) may bel applied after 0d6l6ation with once _through cooling
n4
t6' ', water. :.Pred that momtaring is prior to discharge to waters of the United '
_
j'r_x States Thfe,irterpietation'is subject to.6orLsideration of various factors, .
rL j +.a :s �f`tti e tvyK M +
"n
r jae
sarAa which' are' maoorandum which migh / equine that
9f
, ,y detailed -fn the . tallow z
i J, b^t +.. ,'W",+: ;kms f d. :• ..
k �pAl3mitati�beva�piied priar to 000bination
..
L E LANDRY
VAR 2 81986

Division of Water Resources
Enclosure
Attachment A
Harris Nuclear Plant
NPDES Permit No. NCO039586
US EPA Memorandums on Steam Electric pH Limitations
USEPA, New England - Region I Fact Sheet Draft NPDES Permit for Mirant Canal, L.L.C.
(Highlights /Emphasis Added)

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
NEW ENGLAND - REGION
ONE CONGRESS STREET
BOSTON, MASSACHUSETTS 02114
FACT SHEET
DRAFT NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES)
PERMIT TO DISCHARGE TO WATERS OF THE UNITED STATES
NPDES PERMIT NO.: MA0004928
PUBLIC COMMENT PERIOD:
PUBLIC NOTICE NO.:
NAME AND ADDRESS OF APPLICANT:
Mirant Canal, L.L.C.
9 Freezer Road
Sandwich, MA 02563
NAME AND ADDRESS OF FACILITY WHERE DISCHARGE OCCURS:
Mirant Canal, L.L.C.
9 Freezer Road
Sandwich, MA 02563
SIC CODE: 4911 NAICS Code(s): 221112
RECEIVING WATER: Cape Cod Canal (Basin code 96 CAPE)
CLASSIFICATION: Class SB
CURRENT PERMIT ISSUED: 6-23-1989
EXPIRED: 6-23-1994
RE-APPLICATION: 5-02-199 4
SUPPLEMENT TO APPLICATION: 10-30-2003

Mirant Canal MA0004928
2005 Fact Sheet
use of chlorine will not result in chronic exposure to aquatic life.
Effluent Guideline Limit (Instantaneous Maximum) Outfall 001
In the effluent guidelines for the "Steam Electric Power Generating Point Source Category",
EPA has established a technology-based maximum discharge concentration of 0.2 mg/I for total
residual oxidants ("instantaneous maximum"), based on the best available technology
economically achievable (BAT). The 0.2 mg/L "maximum concentration" limit is an
"instantaneous maximum"limit, meaning that it is the value that shall not be exceeded, at any
time, as clarified in EPA's July 27, 1992, Memorandum from Cynthia Dougherty, Director of the
Permits Division, to the Regional Water Management Division Directors. This technology-
based effluent limit applies to plants with a total generating capacity of more than 25 megawatts
and once -through cooling water systems. Each individual generating unit is prohibited from
discharging chlorine for more than two hours per day, unless the discharger demonstrates to the
permitting authority that a longer duration is necessary in order to control macro -invertebrate
growth. In addition, simultaneous multi -unit chlorination is permitted according to the effluent
guidelines.
Currently, Canal Station is cooled via an open cycle system (Once -Through Cooling Water).
Biofouling of the Units 1 and 2 condenser tubing is controlled by the addition of chlorine, as
sodium hypochlorite (NaOCI), to the cooling water. During the summer months, the NaOCI
pumps for each Unit activate for one hour two times per day. Thus, each Unit receives a total of
2 hours of chlorination per day.
The above derived, technology-based TRO limit shall be measured at Outfall 001, prior to
discharge into the Cape Cod Canal. As noted above, the effluent guidelines specify that permit
limits for TRO shall be setas an "instantaneous maximum." EPA is not aware of continuous
chlorine monitoring equipment for use in salt or brackish water that currently satisfies the
analytical requirements of 40 C.F.R. Part 136, Table 1 B. Therefore, in order to more accurately
determine that the concentration is below the limit for the duration of the chlorination event,
EPA requires that at least one sample is collected and analyzed every half hour during
chlorination.
Subject to the restrictions discussed above, the Draft Permit authorizes the use of chlorine as the
biocide for the Unit I and 2 condensers. Except for chlorine, no other biocide shall be used
without prior written approval from the EPA and MA DEP.
4.4.2 pH
The pH range for Class SB waters is from 6.5 to 8.5 standard units (s.u.) and not more than 0.2
units outside of the normally occurring range as defined in the Massachusetts Surface Water
Quality Standards, found at 314 C.M.R. 4.00. Unless otherwise specified, pH shall be measured
at Outfalls 001 and 002. Monitoring for pH at the internal outfalls 010, 011, and 012 is not
Page 17 of 59

Mirant Canal
2005 Fact Sheet
MA0004928
necessary as explained in EPA's March 21, 1986, Memorandum from Charles Kaplan, EPA's
National Steam Electric/Water Expert, to Regional Permit Branch Chiefs and State Directors.
Using dilution to accomplish the neutralization of pH is preferable to adding chemicals.
4.4.3 Polychlorinated Biphenyl Compounds
Pursuant to 40 C.F.R. Part 423, discharge of polychlorinated biphenyl compounds (PCBs) is
prohibited and any PCB's at the facility must be disposed of in accordance with 40 C.F.R. Part
761.
4.4.4 TSS
The quantity of Total Suspended Solids (TSS) that can be discharged from low volume waste
streams, fly ash transport water and metal cleaning wastes is limited under 40 C.F.R. § 423.12
"by multiplying the flow of low volume waste sources times the concentration listed in the
following table," which is 100 mg/I daily maximum and 30 mg/I monthly average. The Draft
Permit contains TSS limits based on these requirements. In addition, 40 C.F.R. § 423.12(b)(11)
states that the permitting authority has the discretion to express the limits as concentration -based
as opposed to mass -based. The Draft Permit includes concentration -based TSS limits for Outfall
locations 010, 01 1, and 012.
4.4.5 Oil and Grease
The current permit's maximum daily limit for Oil and Grease for Outfall locations 010, 01 l and
012 is 15 mg/I. Although 40 C.F.R. § 423.12 sets a maximum daily limit for Oil and Grease of
20 mg/l, the current permit limits will be maintained in the Draft Permit in accordance with
"anti -backsliding" provisions. Similarly, the average monthly limit is 10 mg/L in the current
permit for Outfall locations 010 and 011, which will be maintained in the Draft Permit. There is
no average monthly limit for O&G in the Station's current permit for Outfall 012. Therefore, in
accordance with 40 C.F.R. § 423.12, the average monthly limit in the Draft Permit for location
012 is 15 mg/L.
4.4.6 Copper
The applicable technology-based national effluent limitation guideline for copper specified in 40
C.F.R. Part 423 is based on the concentration of copper in the metal cleaning waste flow. The
metal cleaning waste stream is routed to one of two waste treatment tanks (Outfall 011) prior to
discharge into the discharge canal. The effluent limitation guidelines set a maximum daily limit
of 1.0 mg/I and a 30 -day average value of 1.0 mg/I. These limits are included in the Draft
Permit.
4.5.7 Iron
Page 18 of 59