NC0038377_Comments on the Draft Permit_20170221

February 21, 2017
Sergei Chernikov, PhD.
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
Subject: Comments on the DRAFT NPDES Permit for Mayo Steam Electric Plant
Permit No.: NCO038377
Person County
Dear Dr. Chernikov:
Richard E. BakerJr., P.E. , P.M.F
Director of Environmental Programs
Coal Combustion Products
526 S. Church Street
Mail Code:EC13K
Charlotte, NC 28202
(704)-382-7856
RECEWBJNCDMDWR
FEB 21 2017
Waterouality
Permitting Section
Duke Energy Progress, LLC (Duke Energy) submits the following comments on the draft National
Pollutant Discharge Elimination System Permit for Mayo Steam Electric Plant, issued for public comment
by the North Carolina Department of Environmental Quality ("NCDEQ") on January 22, 2017. Duke
Energy appreciates NCDEQ's efforts to develop the Draft Permit, which addresses novel issues
associated with surface impoundment modifications required to allow for continued operations while
complying with various Federal and State mandates. Finalizing this wastewater permit is a critical step
to advance that process by authorizing decanting and dewatering of the ash basin and permitting
replacement treatment options. In addition to these general comments, Duke Energy again offers the
following comments and requests for modification and/or clarification on specific provisions of the Draft
Permit:
1. On pages 13 through 19 of 37, Duke Energy notes that the channels between the ash basin dam
and the point represented at "AOW S-3" are identified as effluent channel as referenced in the
DEQ field office staff report. On page 19 of the permit, DEQ requires Duke Energy to install a
fish migration barrier at the point identified as "S-3" "to minimize fish migration into the effluent
channels that are combining at 5-3." Because of this and the designation of all of these flows as
effluent channels, the points flowing to S-3 consisting of releases from points identified in the
permit as outfall 101, 102, 101A, 102A, 1028, 108 and 110 should not be subject to WQBEL's
and should be removed and listed as contributing flows to the final compliance sampling point
at S-3 (which could be identified as outfall 103).
2. On page 6 of 37, Section A.(3), Duke Energy requests the following clarifications and
modifications:

Page )2
Duke Energy requests that the limits for Thallium be removed from the permit as there is no numeric
water quality criterion for Thallium in North Carolina. With no adopted criteria, the State has not
provided any opportunity for public involvement or comment on recommended constituent levels used
in determining permit requirements. Unlike the defined opportunity to comment on proposed criteria
during the triennial review, the only means for public involvement in this case is through commenting
on specific permitting actions. The Division's management has previously indicated no limits for metals
would be included in permits for constituents without numeric criteria and the Division recently
acknowledged this in issuance of the company's Sutton permit in which NC DWR proposed to include an
effluent limit for Aluminum but withdrew that limit in the final permit "because ...North Carolina does
not have [an] Al standard...".
The State of North Carolina just completed an update to its standards through the triennial review
process but did not propose any criteria for Thallium. Additionally, there is no record of a determination
that any limit on Thallium is necessary to protect narrative criteria. To the contrary, the record indicates
that the receiving water currently meets narrative criteria, despite a long history of similar discharges,
indicating that effluent limits are not necessary to protect narrative criteria or designated uses. During
the last permit cycle, Duke Energy has completely eliminated inputs of Fly ash, Bottom ash and FGD
wastewater to outfall 002. The Division has not provided any documentation that the factors required
for consideration in developing a BP1 limit for Thallium have been considered. Additionally, Duke
Energy requests that the limit for Thallium at outfall 002 be removed from the permit for the
following reasons:
a) The conclusion reached in the IRIS Toxicological Review (USEPA, 2009), which DEQ seeks
to base the limit on, was the available toxicity database for Thallium contains studies that
are generally of poor quality. Please see Attachment 1 - Evaluation of Toxicological
Information of Thallium prepared by Haley and Aldrich for DEC. This information is included
in the attachment to these comments and should be considered part of our comments on
the DRAFT permit. In the USEPA Integrated Risk Information System (IRIS) Chemical
Assessment Summary for Thallium, it was stated "The available toxicity database for
thallium contains studies that are generally of poor quality" (USEPA, 2012a). In addition,
there is not currently an oral chronic reference dose (RfD) toxicity value for Thallium
established by the USEPA IRIS or from an USEPA Provisional Peer -Reviewed Toxicity Value
(PPRTV) assessment, which would be used to establish water quality criteria. Due to the
significant uncertainty surrounding the study selection used to establish the values for the
2002 water quality criteria and uncertainty to the relevance of adverse effects of Thallium ,
the values used for the derivation of the 2002 Federal Water Quality Criteria for Thallium
are questionable and greatly overestimates potential risks associated with Thallium
exposure. This is supported by other regulatory and authoritative agencies concluding that
the dataset is currently insufficient for derivation of a non -cancer value for Thallium. In
addition, current intakes of Thallium for a substantial part of the population exceed the
provision screening value with no reported adverse effects reported, which also suggests
that the current value is unrealistic for purposes of regulatory decision making.
3. On page 1 of 37, Duke Energy requests the addition of CrutchfieldBranch... and Mayo Creek to
the designated receiving waters.-�
4. On page 2 of 37, Duke Energy requests the following:

Page 13
a. Removal of the language involving ash sluice water mixing with cooling tower blowdown
prior to discharge. Ash sluice water is not discharged at outfall 008.
b. Removal of FGD wastewater as a contributing flow to Outfall 002. Location "C" depicted
in our August 2016 application update was chosen for the construction of a new FGD
basin. In the August 2016 submittal, Duke Energy requested an overflow discharge
point to Mayo Creek be permitted for location "C. This is similar to the requests that
was made and included in the permit related to a new treatment basins emergency
overflow for the Roxboro Steam Electric Plant. Duke does not envision the release of
water from the future FGD basin, however we have requested permit coverage in case
such a discharge were to occur at some point in the future.
5. On page 3 of 37, Duke Energy requests the following changes be made to the final permit:
a. Outfalls 101A, 102A, 1028, 108, and 110 be removed and listed as contributing flows to
the final compliance sampling point at S-3 via the designated effluent channel. This
sampling point could be identified as outfall 103.
b. Outfall 006b be removed from the NPDES wastewater coverage as it does not constitute
a point source discharge or receive any cooling tower drift flows.
6. On page 4 of 37, Duke Energy requests the removal of the daily temperature monitoring
requirement for outfall 001. The current permit contains no requirement for temperature
monitoring. "Daily" temperature monitoring is not necessary and is overly burdensome. Duke
is amenable to "weekly" testing of temperature at this outfall. Cooling tower blowdown flows
are sent to the ash basin where heat dissipates prior to release to Mayo Reservoir.
7. On page 5 of 37, Duke Energy requests removal of the pH limit from internal outfall 008.
Internal outfalls do not constitute a "point source" discharges as described in 40 CFR
423.12(b)(1). Additional reference information related to pH for internal outfalls is provided in
Attachment 3.
a. Duke Energy requests that method 245.1 be allowed for Mercury analysis at outfall 002,
instead of method 1631E. Compliance with the permit limit imposed can be easily
demonstrated using method 245.1.
b. Duke requests that the sampling for Chlorides associated with the mixing zone be
removed. The chloride wastestream that led to the inclusion of this requirement in the
previous permit (FGD wastewater) has not been discharged in over two years because
of the processing of this flow through the vapor compression evaporator.

Page 14
c. Duke Energy requests that during normal operations and decanting that the Acute
Toxicity testing frequency remain at Quarterly as in the current permit. Duke Energy
has never failed a toxicity test at the Mayo plant and monthly testing during normal
operations is not supported.
8. On page 7 of 37, Duke Energy requests parameters with footnote #8 be removed from the limits
page. The footnote currently states that the limits are not enforced when there is no overflow
from the FGD basin. As discussed in our August 2016 NPDES permit application update, Duke
Energy was still evaluating the location of the FGD settling basin. Since that time the location
has been finalized and any overflow from the basin would not be directed to outfall 002.
Location "C" depicted in our August 2016 application update was chosen for the construction of
a new FGD basin. In the August 2016 submittal, Duke Energy requested an overflow discharge
point to Mayo Creek be permitted for location "C. Duke Energy requests that this location be
permitted as previously requested.
9. On page 8 of 37, Duke Energy requests clarification that the flow limit associated with
dewatering applies only to the water removed from interstitial pore space and not the entire
flow through outfall 002. The station will be operating during the time of ash basin closure and
operational flows will be discharged through outfall 002 at the same time dewatering is
underway. Again, Duke Energy requests the removal of Thallium limits as there is no numeric
water quality criterion for Thallium in North Carolina.
10. On page 10 of 37, Duke Energy requests that the limits for BOD and fecal coliform be removed
from outfall 002A. These constituents are proposed to be monitored at outfall 002 further
down in the treatment process. BOD and Fecal should only be monitored at one point and Duke
requests that it be at the final compliance point outfall 002.
11. On page 23 of 37, Duke Energy requests removal of outfall 006b. This point consists of a
stormwater drain that is approximately 750 feet from Mayo reservoir with no defined channel
leading to the reservoir. Upon further evaluation and site visit with NC DEQ DEMLR staff, Duke
Energy has determined that this point does not constitute a point source discharge. There is no
wastewater component to this particular point.
12. On page 26 of 37, Duke Energy requests that Toxicity testing remain a quarterly requirement
until dewatering commences. Duke Energy has never failed a toxicity test at the Mayo plant and
monthly testing during normal operations is not supported.
13. On page 27 of 37, Duke Energy requests the removal of the weekly testing for chlorides found in
Condition A. (23). There has been no discharge from the FGD wastewater system in over two
years and while Duke wants to maintain the flexibility to treat and discharge this flow in the

Page 15
future, there is no current plan to discharge FGD wastewater. Weekly testing for chlorides is not
necessary. Duke Energy requests that, at a minimum, this sampling change to quarterly or be
eliminated for as long as there remains no discharge from FGD wastewater.
14. On page 30 of 37 in Condition A.(30.), Duke Energy requests modification of the proposed
sampling location for instream monitoring from "1000 feet from Outfall 002" to the pre-existing
Mayo Reservoir sampling station identified as "131". Sampling location "131" is the closest
exisiting monitoring station to the discharge from outfall 002 and its location is shown in the
figure provided in Attachment 2 for reference.
15. On page 31 of 37, Duke Energy requests modification of condition A. (31) to align the wording
with the request found in comment i# 1.
Duke Energy welcomes any further discussion on our comments or the Draft Permit. Duke Energy
requests the opportunity to discuss the specific comments and concerns outlined in this letter in person
prior to the subject permit being finalized. If you have any questions, please contact Shannon Langley at
919.546.2439 or at [e-mail].
Sincerely,
Richard E. Bakerlr., P.E., P.M.P
Director of Environmental Programs - CCP
Duke Energy
Attachment
Cc: Mr. John Hennessey—Mayo Public Hearing officer
1617 Mail Service Center
Raleigh, NC 27699-1617

9 17
Attachment 1
"�'CDFQ1BVVR
1166 212017
WaterQnaiity
Permitting Section
Evaluation of Toxicological Information
of
Thallium prepared by Haley and Aldric
k for DEC

DUKE
February 21, 2017
Sergei Chernikov, PhD.
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
Subject: Comments on the DRAFT NPDES Permit for Mayo Steam Electric Plant
Permit No.: NCO038377
Person County
Dear Dr. Chernikov:
Richard E. BakerA, P.E. , P.M.F
Director of Environmental Programs
Coal Combustion Products
526 S. Church Street
Mail Code:EC13tc
Charlotte, NC28202
(704)-382-7955
RECENEMCDEUDWR
FEB 21 2017
WaterQuality
Permitting Section
Duke Energy Progress, LLC (Duke Energy) submits the following comments on the draft National
Pollutant Discharge Elimination System Permit for Mayo Steam Electric Plant, issued for public comment
by the North Carolina Department of Environmental Quality ("NCDEQ") on January 22, 2017. Duke
Energy appreciates NCDEQ's efforts to develop the Draft Permit, which addresses novel issues
associated with surface impoundment modifications required to allow for continued operations while
complying with various Federal and State mandates. Finalizing this wastewater permit is a critical step
to advance that process by authorizing decanting and dewatering of the ash basin and permitting
replacement treatment options. In addition to these general comments, Duke Energy again offers the
following comments and requests for modification and/or clarification on specific provisions of the Draft
Permit:
1. On pages 13 through 19 of 37, Duke Energy notes that the channels between the ash basin dam
and the point represented at "AOW S-3" are identified as effluent channel as referenced in the
DEQ field office staff report. On page 19 of the permit, DEQ requires Duke Energy to install a
fish migration barrier at the point identified as "S-3" "to minimize fish migration into the effluent
channels that are combining at S-3." Because of this and the designation of all of these flows as
effluent channels, the points flowing to S-3 consisting of releases from points identified in the
permit as outfall 101, 102, 101A, 102A, 1028, 108 and 110 should not be subject to WQBEL's
and should be removed and listed as contributing flows to the final compliance sampling point
at S-3 (which could be identified as outfall 103).
2. On page 6 of 37, Section A.(3), Duke Energy requests the following clarifications and
modifications:

Page 12
Duke Energy requests that the limits for Thallium be removed from the permit as there is no numeric
water quality criterion for Thallium in North Carolina. With no adopted criteria, the State has not
provided any opportunity for public involvement or comment on recommended constituent levels used
in determining permit requirements. Unlike the defined opportunity to comment on proposed criteria
during the triennial review, the only means for public involvement in this case is through commenting
on specific permitting actions. The Division's management has previously indicated no limits for metals
would be included in permits for constituents without numeric criteria and the Division recently
acknowledged this in issuance of the company's Sutton permit in which NC DWR proposed to include an
effluent limit for Aluminum but withdrew that limit in the final permit "because ...North Carolina does
not have [an] Al standard...
The State of North Carolina just completed an update to its standards through the triennial review
process but did not propose any criteria for Thallium. Additionally, there is no record of a determination
that any limit on Thallium is necessary to protect narrative criteria. To the contrary, the record indicates
that the receiving water currently meets narrative criteria, despite a long history of similar discharges,
indicating that effluent limits are not necessary to protect narrative criteria or designated uses. During
the last permit cycle, Duke Energy has completely eliminated inputs of Fly ash, Bottom ash and FGD
wastewater to outfall 002. The Division has not provided any documentation that the factors required
for consideration in developing a BPJ limit for Thallium have been considered. Additionally, Duke
Energy requests that the limit for Thallium at outfall 002 be removed from the permit for the
following reasons:
a) The conclusion reached in the IRIS Toxicological Review (USEPA, 2009), which DEQ seeks
to base the limit on, was the available toxicity database for Thallium contains studies that
are generally of poor quality. Please see Attachment 1 - Evaluation of Toxicological
Information of Thallium prepared by Haley and Aldrich for DEC. This information is included
in the attachment to these comments and should be considered part of our comments on
the DRAFT permit. In the USEPA Integrated Risk Information System (IRIS) Chemical
Assessment Summary for Thallium, it was stated "The available toxicity database for
thallium contains studies that are generally of poor quality" (USEPA, 2012a). In addition,
there is not currently an oral chronic reference dose (RfD) toxicity value for Thallium
established by the USEPA IRIS or from an USEPA Provisional Peer -Reviewed Toxicity Value
(PPRTV) assessment, which would be used to establish water quality criteria. Due to the
significant uncertainty surrounding the study selection used to establish the values for the
2002 water quality criteria and uncertainty to the relevance of adverse effects of Thallium ,
the values used for the derivation of the 2002 Federal Water Quality Criteria for Thallium
are questionable and greatly overestimates potential risks associated with Thallium
exposure. This is supported by other regulatory and authoritative agencies concluding that
the dataset is currently insufficient for derivation of a non -cancer value for Thallium. In
addition, current intakes of Thallium for a substantial part of the population exceed the
provision screening value with no reported adverse effects reported, which also suggests
that the current value is unrealistic for purposes of regulatory decision making.
3. On page 1 of 37, Duke Energy requests the addition of Crutchfield Branch and MauCreek to
the designated receiving waters.
4. On page 2 of 37, Duke Energy requests the following:

a. Removal of the language involving ash sluice water mixing with cooling tower blowdown
prior to discharge. Ash sluice water is not discharged at outfall 008.
b. Removal of FGD wastewater as a contributing flow to Outfall 002. Location "C" depicted
in our August 2016 application update was chosen for the construction of a new FGD
basin. In the August 2016 submittal, Duke Energy requested an overflow discharge
point to Mayo Creek be permitted for location "C". This is similar to the requests that
was made and included in the permit related to a new treatment basins emergency
overflow for the Roxboro Steam Electric Plant. Duke does not envision the release of
water from the future FGD basin, however we have requested permit coverage in case
such a discharge were to occur at some point in the future.
5. On page 3 of 37, Duke Energy requests the following changes be made to the final permit:
a. Outfalls 101A, 102A, 102B, 108, and 110 be removed and listed as contributing flows to
the final compliance sampling point at S-3 via the designated effluent channel. This
sampling point could be identified as outfall 103.
b. Outfall 006b be removed from the NPDES wastewater coverage as it does not constitute
a point source discharge or receive any cooling tower drift flows.
6. On page 4 of 37, Duke Energy requests the removal of the daily temperature monitoring
requirement for outfall 001. The current permit contains no requirement for temperature
monitoring. "Daily" temperature monitoring is not necessary and is overly burdensome. Duke
is amenable to "weekly" testing of temperature at this outfall. Cooling tower blowdown flows
are sent to the ash basin where heat dissipates prior to release to Mayo Reservoir.
7. On page 5 of 37, Duke Energy requests removal of the pH limit from internal outfall 008.
Internal outfalls do not constitute a "point source" discharges as described in 40 CFR
423.12(b)(1). Additional reference information related to pH for internal outfalls is provided in
Attachment 3.
a. Duke Energy requests that method 245.1 be allowed for Mercury analysis at outfall 002,
instead of method 1631E. Compliance with the permit limit imposed can be easily
demonstrated using method 245.1.
b. Duke requests that the sampling for Chlorides associated with the mixing zone be
removed. The chloride wastestream that led to the inclusion of this requirement in the
previous permit (FGD wastewater) has not been discharged in over two years because
of the processing of this flow through the vapor compression evaporator.

c. Duke Energy requests that during normal operations and decanting that the Acute
Toxicity testing frequency remain at Quarterly as in the current permit. Duke Energy
has never failed a toxicity test at the Mayo plant and monthly testing during normal
operations is not supported.
8. On page 7 of 37, Duke Energy requests parameters with footnote #8 be removed from the limits
page. The footnote currently states that the limits are not enforced when there is no overflow
from the FGD basin. As discussed in our August 2016 NPDES permit application update, Duke
Energy was still evaluating the location of the FGD settling basin. Since that time the location
has been finalized and any overflow from the basin would not be directed to outfall 002.
Location "C" depicted in our August 2016 application update was chosen for the construction of
a new FGD basin. In the August 2016 submittal, Duke Energy requested an overflow discharge
point to Mayo Creek be permitted for location "C. Duke Energy requests that this location be
permitted as previously requested.
9. On page 8 of 37, Duke Energy requests clarification that the flow limit associated with
dewatering applies only to the water removed from interstitial pore space and not the entire
flow through outfall 002. The station will be operating during the time of ash basin closure and
operational flows will be discharged through outfall 002 at the same time dewatering is
underway. Again, Duke Energy requests the removal of Thallium limits as there is no numeric
water quality criterion for Thallium in North Carolina.
10. On page 10 of 37, Duke Energy requests that the limits for BOD and fecal coliform be removed
from outfall 002A. These constituents are proposed to be monitored at outfall 002 further
down in the treatment process. BOD and Fecal should only be monitored at one point and Duke
requests that it be at the final compliance point outfall 002.
11. On page 23 of 37, Duke Energy requests removal of outfall 006b. This point consists of a
stormwater drain that is approximately 750 feet from Mayo reservoir with no defined channel
leading to the reservoir. Upon further evaluation and site visit with NC DEQ DEMLR staff, Duke
Energy has determined that this point does not constitute a point source discharge. There is no
wastewater component to this particular point.
12. On page 26 of 37, Duke Energy requests that Toxicity testing remain a quarterly requirement
until dewatering commences. Duke Energy has never failed a toxicity test at the Mayo plant and
monthly testing during normal operations is not supported.
13. On page 27 of 37, Duke Energy requests the removal of the weekly testing for chlorides found in
Condition A. (23). There has been no discharge from the FGD wastewater system in over two
years and while Duke wants to maintain the flexibility to treat and discharge this flow in the

Pad=e I5
future, there is no current plan to discharge FGD wastewater. Weekly testing for chlorides is not
necessary. Duke Energy requests that, at a minimum, this sampling change to quarterly or be
eliminated for as long as there remains no discharge from FGD wastewater.
14. On page 30 of 37 in Condition A.(30.), Duke Energy requests modification of the proposed
sampling location for instream monitoring from "1000 feet from Outfall 002" to the pre-existing
Mayo Reservoir sampling station identified as "B1". Sampling location "B1" is the closest
exisiting monitoring station to the discharge from outfall 002 and its location is shown in the
figure provided in Attachment 2 for reference.
15. On page 31 of 37, Duke Energy requests modification of condition A. (31) to align the wording
with the request found in comment # 1.
Duke Energy welcomes any further discussion on our comments or the Draft Permit. Duke Energy
requests the opportunity to discuss the specific comments and concerns outlined in this letter in person
prior to the subject permit being finalized. If you have any questions, please contact Shannon Langley at
919.546.2439 or at [e-mail].
Sincerely,
�J � SV it,
Richard E. Baker Jr., P.E., P.M.P
Director of Environmental Programs - CCP
Duke Energy
Attachment
Cc: Mr. John Hennessey—Mayo Public Hearing officer
1617 Mail Service Center
Raleigh, NC 27699-1617

Attachment 1
g 17
Waterauality
Permitting Section
Evaluation of Toxicological Information of
Thallium prepared by Haley and Aldri
ck for DEC

Thallium Toxicity Value Review
EVALUATION OF THE TOXICITY VALUE FOR THALLIUM
1. Current Screening Provisional Toxicity Value
There is not currently an oral chronic reference dose (RfD) toxicity value for thallium established by the
United States Environmental Protection Agency (USEPA) Integrated Risk Information System (IRIS) or
from an USEPA Provisional Peer -Reviewed Toxicity Value (PPRTV) assessment. The USEPA PPRTV
document for thallium (TI) concluded that it is inappropriate to derive a provisional subchronic or
chronic provisional RfD (p-RfD) for thallium; however, USEPA states that information is available which,
although insufficient to support derivation of a provisional toxicity value under current guidelines, may
be of limited use to risk assessors (USEPA, 2012). The PPRTV document contains a separate Appendix A
that provides rationale for the derivation of a subchronic and chronic "screening provisional oral
reference dose" for thallium compounds of 0.00004 mg TI/kg-day and 0.00001 mg TI/kg-day,
respectively. Appendix A of the PPRTV document also notes that, "Users of screening toxicity values in
an appendix to a PPRTV assessment should understand that there is considerably more uncertainty
associated with the derivation of a supplemental screening toxicity value than for a value presented in
the body of the assessment (USEPA, 2012a)." The screening p-RfD is expressed in units of milligrams of
thallium per kilogram of body weight per day (mg TI/kg-day).
Due to limitations in the toxicology database and general poor quality of available studies, the USEPA
IRIS Toxicological Review of Thallium and Compounds (USEPA, 2009) also concluded that reference
doses or reference concentrations could not be derived for human health following thallium exposures.
2. Information on Human Exposure to Thallium
The conservative nature of the p-RfD can be illustrated by considering the amount of thallium ingested
daily by Americans in their diet. It is estimated by the World Health Organization (WHO) and the U.S.
Agency for Toxic Substances for and Disease Registry (ATSDR) that a 70 kilogram adult ingests
approximately 0.005 mg thallium per day in the diet, especially from consumption of home-grown fruits
and green vegetables (WHO, 1996; ATSDR, 1992). This is equivalent to a daily dose of 0.00007 mg TI/kg-
day. The USEPA supplemental p-RfD for thallium is 1E-05 mg/kg -day (0.00001 mg/kg -day). This is seven
times lower than the estimated dietary intake. In other words, use of this dose -response value to
evaluate natural dietary exposure to thallium would indicate a hazard that is unlikely to exist.
Stated another way, assuming that an average adult weighs 70 kg, and using the screening level p-RfD of
0.00001 mg/kg bw-day, it could be concluded that an adult should not consume more than 0.0007 mg
TI/day, which is well below the estimated dietary intake of 0.005 mg thallium per day in the diet.
Currently, there have not been substantial reports of toxicological effects associated with typical dietary
ingestion of TI in the general population, suggesting that the use of the "screening provisional oral
reference dose" greatly overestimates the potential risks associated with oral exposure to TI
compounds.
The 90`h percentile adult urinary thallium elimination from the National Health and Nutrition
Examination Survey (NHANES) (CDC, 2016) is 0.380-0.390 micrograms per liter (ug/L) which is about
0.760-0.780 ug/day in the urine alone. This suggests that greater than 10% of Americans, and probably
November 2016 1
Aj­
'JAICK

Thallium Toxicity Value Review
closer to 50% of Americans, ingest more than the screening level p-RfD. From the IRIS assessment
conducted in 2009, a reviewer stated that there is no evidence that thalliurn in the current U.S. diet
poses any Threat, and the adoption of this screening level p-RfD would produce unnecessary concern if
the above calculation is correct. This indicates the poor quality of the existing data, and brings into
question the validity of the analysis using the available data on thallium used by USEPA (USEPA, 2009).
I Derivation of the Current Screening Provisional Toxicity Value
Below is a summary of the data and assessment that was used by USEPA in the derivation of the oral
chronic screening level p-RfD for thallium.
3A HAZARD EVALUATION/STUDY SELECTION
Note: Human or animal studies examining the carcinogenicity of thallium following oral exposure are
not available. The cancer weight -of -evidence (WOE) provided in the IRIS review (USEPA, 2009) is listed
as 'Inadequate Information to Assess Carcinogenic Potential (both oral and inhalation).'
3.1.1 tlL011an
Most information on thallium toxicity in humans comes from poisonings, suicide attempts, or accidental
exposures. Symptoms observed after acute exposures to high doses of thallium in humans include
alopecia (hair loss), gastrointestinal disturbances, and neurological symptoms such as paresthesia and
neuropathy. Epidemiologic studies of either the general population or occupationally exposed groups
are limited by inadequate study design, undefined exposure parameters, and inconclusive associations
between thallium exposure and specific health effects. Therefore, USEPA (2012a) concluded in the
PPRTV document that "available human studies do not support oral RfD derivation."
3.1.2 Animal studies
Studies in animals show that oral exposure to thallium produces effects similar to those observed in
iochemical
humans, most notably, alopecia. Other findings observed in animal studies include b
changes, lipid peroxidation, liver and kidney damage, and histopathologic changes in brain and
8 the
nerves. The doses at which these systemic effects were observed range from 0.2 —1. a TI/kg-day
(ATSDR, 1992). Reproductive and developmental studies in animals show some evidence of adverse
g
effects upon oral exposure to thallium at doses of 0.08 mg TI/kg-day —1.6 mTI/kg day; however,
(ATSDR, 1992).
available studies have significant limitations and the same effects have not been observed in humans
Only four repeat -dose oral toxicity studies with more than one dose level are available in animals. Of
these four studies, three were not considered adequate for RfD derivation (USEPA, 2009).
3.1.3 Corsclusio,l,
The conclusion reached in the IRIS Toxicological Review (USEPA, 2009) was that the available toxicity
database for thallium contains studies that are generally of poor quality. One animal subchronic study
conducted by the Midwest Research Institute (MRI, 1988) was selected as a candidate principal study for
November 2016 2
HRSiC

Thallium Toxicity Value Review
RfD derivation but was found to include critical limitations such as high background incidence of
alopecia, lack of histopathological examination of skin tissue in low -and mid -dose groups, and
inadequate examination of objective measures of neurotoxicity, thus making it difficult to select
appropriate endpoints. On this basis, a RfD for thallium salts was not derived by IRIS (USEPA, 2012a).
3,2 BASIS FOR PROVISIONAL SCREEtiING ORAL CHRONIC P -RFD
As indicated above, the PPRTV assessment (USEPA, 2012a) does not derive a typical provisional toxicity
value for thallium but rather uses the limited toxicological information to develop a screening level
value.
3,2.1 Study Selection
A 90 -day Good Laboratory Practice (GLP) oral gavage study in male and female rats conducted with
thallium sulfate by MRI (1988) was selected as the principal study for the screening level p-RfD. Doses
were approximately 0, 0.008, 0.04, and 0.2 mg TI/kg-day.
Several critical endpoints were considered, but ultimately USEPA (2009) considered only two endpoints
to be appropriate for a screening level p-RfD development:
• Hair follicle atrophy in female rats that also had alopecia; and
• Clinical observations related to animal coat, eyes, and behavior.
The clinical observation endpoint was discounted because the underlying basis for the observations is
unknown. Hair follicle atrophy was determined to be most consistent with the atrophic changes
observed in cases of human thallium poisoning and may be best indication for human response to
thallium exposure.
MRI (1998) concluded that the minor dose-related changes in the study did not affect the health status
of the treated animals and were not toxicologically significant. MRI considered the highest dose (0.2 mg
TI/kg-day) as the no -observed -effect level (NOEL). However, USEPA conducted its own analyses of the
raw data from the study to come up with different conclusions. Of the 12 high -dose females with
alopecia, 5 instances were not totally attributed to barbering behavior. Histopathologic examinations
revealed atrophy of the hair follicles in two high -dose female rats that also had alopecia. It was noted
that there were no discernable differences in either the severity or distribution pattern of alopecia
across control and treated groups (USEPA, 2009).
The high dose (0.2 mg TI/kg-day) was identified by USEPA as the LOAEL. Because histapathology of skin
tissue from the low -and mid -dose groups was not conducted, the NOAEL for this endpoint cannot be
determined with certainty. Given the low incidence of hair follicle atrophy in females in the high dose
group and absence of cases of hair follicle atrophy in male rats, USEPA (2012a) assumed that the mid -
dose could be used to approximate a NOAEL for skin histopathology.
November 2016 3 �w _ 5.

Thallium Toxicity Value Review
Therefore, the estimated NOAEL of 0.04 mg TI/kg-day was used as the point of departure (POD) for hair
follicle atrophy (USEPA, 2012a).
Using the NOAEL of 0.04 mg TI/kg-day for hair follicle atrophy and using an uncertainty factor (UF) of
3000, the screening level p-RfD was calculated to be 0.00001 mg TI/kg-day. justification for the applied
OF is summarized in table below.
Table 1: Uncertainty Factors Applied by USEPA in Screening Level p-RfD Derivation
Uncertainty Factor Justification
10 _ r -- i
Extrapolation from laboratory animals to humans since no information is
available to characterize the toxicokinetic differences between experimental
animals and humans.
10 Variation in human susceptibility in the absence of information on the
variability of response to thallium in the human population.
10 Lack of adequate developmental toxicity studies and a two -generation
reproductive study, and additional uncertainty associated with the limited
data available on neurotoxicity.
3 Extrapolation from subchronic to chronic exposure duration. Effects on the
coat/skin as well as other clinical observations occur within weeks of exposure
to thallium {does nnt required chronic exposure in order to manifest).
Composite OF = 3000
Note that there are considerable and critical limitations with the principal study selected by USEPA
(2009) including:
High background of incidence of alopecia (POD selected)
Lack of histopathological examination of skin tissue in low -and mid -dose groups
Inadequate examination of objective measures of neurotoxicity
4. Other Available Sources for Derivation of Toxicity Values for Thallium
The following sections describe sources consulted for information on the toxicology of thallium.
4.2 WORLD HEALTH ORGANIZATION
The World Health Organization (WHO) (1996) concluded that in the general population, environmental
exposure to thallium does not pose a health threat. The total intake has been estimated to be less than
5 ug/day with the vast majority coming from foodstuffs; drinking -water and air generally contribute very
small amounts of thallium. Concentrationsof thallium in urine may be considered a relatively reliable
indicator of exposure. Exposure to thallium resulting in urine concentrations below 5 ug/liter is unlikely
to cause adverse human health effects. The estimated daily oral intake corresponding to a urinary
thallium concentration of 5 ug/liter in urine is approximately 10 ug thallium in the form of a soluble
compound. Assuming an average adult body weight of 80 kg (USEPA, 2014), this would be equivalent
to 0.000125 mg/kg -day which is a 10 -fold factor above the USEPA screening level p-RfD. The WHO
November 2016
4
r

Thallium Toxicity Value Review
Task Group thus concluded that "in view of the considerable uncertainties in the evaluation, it was not
possible to recommend a health -based exposure limit. Until better information on the dose -response
relationship becomes available, it seems prudent to keep human exposures at levels that lead to urinary
concentrations of less than 5 ug/liter." In reviewing the animal studies, the WHO Task Group also noted
that, "it appears that an intake of 0.01 mg/kg -day may be associated with adverse effects. No doses
lower than this have been tested."
ATSDR (1992) notes, "Data on effects of intermediate duration oral exposure in animals do not reliably
identify the most sensitive target organ or the threshold for adverse effects. No data on effects of
chronic -duration oral exposure to thallium were located. Therefore, intermediate -duration and chronic -
duration oral minimum risk levels (MRLs) were not derived for thallium." Note that review of the MR!
1988 study (originally Stoltz 1985) was conducted by ASTDR but not used in the derivation of the MRL.
w3
USEPA's Maximum Contaminant Level (MCL) (USEPA, 2012b) for drinking water is 2.0 ug/L or 0.002
mg/L. The USEPA Human Health Water Quality Criteria (HHWQC) (USEPA, 2015) for thallium is 0.24 ug/L
or 0.00024 mg/L for the consumption of water and organisms from a surface water body, and is 0.47
ug/L or 0.00047 mg/L for the consumption of organisms only. These levels were derived based on the
90 -day subchronic study in rats (MRI, 1988).
4.4 CALIFORNIA EPA
In California, the MCL and Public Health Goal (PHG) for thallium in drinking water are currently set at 2.0
and 0.1 ug/L, respectively (CaIEPA, 1999, 2004). The Office of Environmental Health Hazard Assessment
(OEHHA) prepared the PHG for thallium in drinking water also using the MRI (1988) study in which
alopecia was observed in both male and female rats and consistent with other reports of toxicity of
thallium in both experimental animals and in humans. OEHHA determined that the incidence of
alopecia in female rats at the highest dose of 0.25 mg/kg -day represented a biologically significant
effect. Therefore, the no -observed -effect -level (NOEL) was identified to be the administered mid -dose
level of 0.04 mg TI/kg-day. For the calculation of the PHG, a cumulative uncertainty factor of 3,000 was
incorporated to account for the use of a subchronic study, uncertainty in inter -and intra -species
extrapolation and the steep dose -response curve. Based on these uncertainty factors, OEHHA derived a
PHG for thallium in drinking water of 0.0001 mg/L (0.1 ug/L). OEHHA notes that USEPA chose to
consider the dose that resulted in alopecia and increased serum enzymes indicated of liver damage as a
NOAEL, which is why the federal values are higher than those estimated by OEHHA.
411.5 CANADIAN COUNCIL OF INIiNISTERS OF THE ENVIR NPSIENT
The Canadian Council of Ministers of the Environment (1999) also adopted the USEPA screening level p-
RfD based on the MRI (1988) study as a provisional tolerable daily intake (TDI) for derivation of health -
based soil quality guidelines for thallium at contaminated sites in Canada.
November 2016 5
AMAICrH

Thallium Toxicity Value Review
No data were available on thallium or thallium compounds on the European Chemical Agency (ECHA)
Portal where the Registration, Evaluation, Authorization and Restriction of Chemical Substances (REACH)
Registration Dossiers are posted (ECHA, 2016). Thus, no derived no effect level (DNEL) is available for
thallium from this source.
OT#'HER
No other relevant data were located with respect to thallium toxicity since the publication of the USEPA
PPRTV assessment that could better inform the dose -response assessment and toxicity value derivation
for thallium.
5. Critique of Toxicity Value for Thallium
The current screening level p-RfD currently being used by USEPA as a toxicity value is a highly
conservative and inappropriate value for use in evaluating human health risks from oral chronic
exposure to thallium on the basis of; 1) the lack of appropriate toxicological studies on subchronic and
chronic exposures to thallium that provide relevant data and endpoints to be used in a dose -response
assessments; 2) the fact that other regulatory authorities (ATSDR, WHO) have concluded that sufficient
data on thallium does not exist and have not generated toxicity values for thallium and have placed a
low priority on development of additional toxicology data for thallium; 3) the study and POD using
alopecia as the endpoint as selected for the derivation of the screening level p-RfD by USEPA (2012a)
results in significant uncertainty to the applicability of the effects to human exposure to thallium; and 4)
the screening level p-RfD greatly overestimates the risk associated with human exposures as compared
to the typical ingestion of thallium in foods.
5.1 TOXICOLOGY DATABASE ON THALLIUM
The toxicity database for thallium in consideration of a dose -response assessment and derivation of a
toxicity value is limited. Low confidence in the screening level p-RfD is attributed to the limited
database including the lack of studies addressing the known toxic effects of thallium including
neurotoxicity, developmental toxicity, and endocrine effects, and failure of the MRI (1988) study to
identify a NOAEL of all relevant endpoints are considered. It is questionable as to whether a screening
level p-RfD should have been derived and if such an analysis is even valid knowing the database
limitations resulting in the application of such high uncertainty factors, given USEPA's own discussion of
the limitations in the PPRTV document (USEPA, 2012a).
OTHER REGULATORY SCURCES/V°ALIJES
Most regulatory sources acknowledge the paucity of data for thallium and have not derived toxicity
values. USEPA IRS, WHO, and ATSDR have not generated oral chronic RfDs for thallium. For those that
have, the MRI (1988) study has been identified as the principal study despite the fact that it has not
been published in a peer-reviewed journal, did not provide statistical analyses, and the study did not
show a statistically significant dose -response effect for alopecia in male rats.
November 2016 6
abhICH

Thallium Toxicity Value Review
On the Priority List of Hazardous Substances established by ATSDR last updated February 12, 2016,
thallium is listed as #275 out of 275 compounds indicating its low priority and concern for review
In addition, the National Toxicology Program (NTP) (2016a) has
reviewed petitions and proposals for conducting additional toxicology studies on thallium to decrease
the limitations and uncertainty with the current toxicology database but in a recent meeting on June 15,
2016, the NTP scientific board placed low priority on moving forward with these efforts.
One could infer that the low priority established by regulatory authorities on continued development
and review of the toxicology data for thallium indicates a low concern of the potential for human health
risk effects of oral exposures to thallium as compared to other compounds.
STUDY SELECTIONAND POD
ft has been questioned as to whether alopecia is considered an adverse event and should have been
used as the POD for the screening level p-RfD. USEPA has stated: "Whether alopecia is itself an adverse
effect merits consideration. In humans, alopecia is generally reversible upon cessation of thallium
exposure. Alopecia, however, appears to be a part of a continuum of dermal changes observed
following thallium exposure, as well as one of a spectrum of effects on target organs that include the
nervous and gastrointestinal systems. For these reasons, alopecia supported by two cases of hair follicle
atrophy is considered an adverse effect (USEPA, 2009)." USEPA (2009) acknowledged that other factors
such as caging and husbandry can cause alopecia in laboratory rodents; however, the incidence was
clearly elevated in both male and female rats over controls. Further, to the extent that alopecia was due
to barbering, research has shown that barbering in rodents can reflect a stress -evoked behavioral
response. For these reasons, some IRIS reviewers thought it was reasonable to use the alopecia as a
"biomarker" for adverse effects until additional studies are conducted to better identify adverse effects
of thallium exposures in animals and/or humans.
NTP (2016b) has also noted that the dose selection for the subchronic study was deemed inappropriate
for evaluation of alopecia since the 14 -day range -finding study performed prior to the 90 -day study
indicated hair follicle alterations together with decreases in body weight at a dose of 2.5 mg/kg -day of
thallium sulfate; however, a dose of ten times lower than that which effects were noted, 0.25 mg/kg -day
thallium sulfate was chosen as the high dose in the subchronic study. Further, review of the results also
show that there were challenges in distinguishing between normal hair cycling, self -barbering, and
incidences of true alopecia.
Since hair follicle histopathology and self -barbering is not a standard assessment in subchronic studies, it
is difficult to know whether what was observed in the MRI study (1988) is within the range of normal or
truly adverse. Therefore, the use of this endpoint as the POD brings considerable uncertainty to the
screening level p-RfD derived using these data.
No other studies have been identified by reviewers that could bring more certainty and validity to the
current screening level p-RfD proposed by USEPA (2012a).
November 2016
7

Thallium Toxicity Value Review
6. Final Assessment
Due to the significant uncertainty surrounding the study selection and uncertainty to the relevance of
adverse effects in the selected study and POD, the screening level p-RfD value as provided in Appendix A
of the USEPA PPRTV document for thallium (USEPA, 2012a) greatly overestimates potential risks
associated with exposure to TI. This is supported by other regulatory and authoritative agencies
concluding that the dataset is currently insufficient for derivation of a non
addition, current intakes of TI for a substantial part of the population exceed the provision screening
value with no reported adverse effects reported, which also suggests that the current value is unrealistic
for purposes of regulatory decision making.
Therefore, it seems most appropriate to establish a screening level based on the level of thallium in the
diet; clearly exposure to thallium at this level are without adverse effects. Using the information from
t
WHO (1996) that the estimated daily oral intake corresponding to a urinary thallium concenration of
5 ug/liter in urine is approximately 10 ug thallium in the form of a soluble compound, and assuming
an average adult body weight of 80 kg (USEPA, 2014), a RfD of 0.000125 mg/kg -day can be calculated,
which is a 10 -fold factor above the USEPA screening level p-RfD. This value is still a conservative
derivation, considering that it is well below the intake of 0.01 mg/kg -day that WHO indicated was the
lowest associated with adverse effects.
7. References
1. ATSDR. 2004. Toxicological Profile for Cobalt. U.S. Department of Health and Human Services,
Public Health Service, Agency for Toxic Substances and Disease Registry. Available at:
h�'tt?_ E'v�sys�acs , cd_.LL0v,text:_0Fi'e3!T�'.�'sR"�id-3n til�a0
`9 L . t.
2. CDC. 2016. National Health and Nutrition Examination Survey. U.S. Center for Disease Control and
Prevention. Available at:
3. CalEPA. 1999. Public Health Goal for Thallium in Drinking Water. Office of Environmental Health
Hazard Assessment (OEHHA). Available at:
4. CaIEPA. 2004. Update of Public Health Goal (PHG)-Thallium. Office of Environmental Health Hazard
Assessment (OEHHA). Available at:
5. Canadian Council of Ministers of the Environment. 1999. Canadian soil quality guidelines for the
protection of environmental and human health: Thallium (1999). In: Canadian environmental quality
guidelines, 1999, Canadian Council of Ministers of the Environment, Winnipeg. Available at:
6. ECHA. 2016. ECHA Portal for Registration, Evaluation and Authorisation of Chemicals (REACH)
Registered Substances. European Chemicals Agency (ECHA). Available from:
i=ti si'at::�:"#*t3�1•v�'#_c;�,- r. a
_ C tf a�if ? S f?istered- - bhst-lnce5
November 2016 $
AL

Thallium Toxicity value Review
7. OEHHA. 1999. Public Health Goal for thallium in drinking water. Office of Environmental Health
Hazard Assessment, Berkeley and Sacramento, CA. Accessible at
8. NTP. 2016a, NTP Board of Scientific Counselors Meeting. Webinar presentation. Thallium
Compounds. June 15. See: httLL,; tU>r,
3.r.i i?I:£uJ�1�
9. NTP. 2016b. Draft NTP Board of Scientific Counselors Meeting. NTP Research Concept: Thallium
Compounds. June 15-16. Available at:
h;}Ci; liil r J.! -F i,?3 / ti � ...
15.niI1. r, •, JV%i)tC, / 2:c Crtic n J�..Li;-'
.>>lli.t.;1t:�illf"1r?^i`f7f�=:�tE1'..,
10. USEPA. 2009, Toxicological Review of Thallium and Compounds -In Support of Summary
Information on the Integrated Risk Information System (IRIS). September. Available at:
11. USEPA. 2012a. Final Provisional Peer Reviewed Toxicity Values for Thallium and Compounds.
Superfund Health Risk Technical Support Center, National Center for Environmental Assessment,
Office of Research and Development, US Environmental Protection Agency, Cincinnati, OH.
Available at: htt,,:�i;
12. USEPA. 2012b. USEPA 2012 Edition of the Drinking Water Standards and Health Advisories, Spring
2012. U.S. Environmental Protection Agency. Available at:
'�ti�/��iS.Oin . i11:/{I��ilmeili5/?f I.- :'i nitiTS ' d: Fr
13. USEPA. 2014. Human Health Evaluation Manual, Supplemental Guidance: Update of Standard
Default Exposure Factors. OSWER 9200.1-120. February 6, 2011. U.S. Environmental Protection
Agency. Available t
i able at: 7t nrn ;IsU: �Exe'Z *?rF1`' I?_rJ PDF
DF
14. USEPA. 2015. Human Health Ambient Water Quality Criteria. U.S. Environmental Protection
Agency. Available at `tTS
15. WHO. 1996. Thallium. Environmental Health Criteria 182. World Health Organization. Available
at:
November 2016 9
L ICti

1 r.

Attachment 2
Mayo Reservoir Sampling Locations

N
Mayo Reservoir Sampling Locations
2 `
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Attachment 3
Reference document on internalp H limits
related to ELG's

UNITED 6°'TATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 204fp
OCT 18
Mr. Louis Canziani
New York State
Department of Environmental
Conservation
Room 6126
Two World Trade Center
New York, NY 10047
Dear Mr. Canzisni:
This is to confirm our recent conversation regarding
effluent limitations guidelines for the steam electric poorer
industry (40 CFP Part 423).
In my letter of June 22, 1984 to lis. Ursula Basch of
your office, I summarized theapplicability of the steam
electric regulation pH limitat-ion 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 instruc-
tions provided to EPA and State permitting authorlties 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 Pert 423 is
etso that the total suspended solids and oil and grease
limitations applic"It-t.a low volume waste streams be applied
to the 1OM Glume haste COMP onent of such a combined di$charge
prior to eammingling Of the individual waste streams.
I apologize for any confusion in permit development or
delays In permit Issuance that mvy have occurred in this
matter. If you have any further questions, please contact me
at [phone].
Sincerely,
1
Dennis Ruddy'
Project Officer
Industrial Technology Division

JUN 2 2 ! 0 n
Ms. Ursula Basch
New York State
Department of Environmental
Conservation
Room 6126
2 WorJd TradrA C.nntpr
New York, New York 10047
Dear his. Basch:
This is in resr)onse tn' your r�„estinns �urjng our
discussion on June 21 rc9ard-Ing the Pffluent limitations
guidelines for the steam electric industry (40 CFR Part 423).
T e pH limitation a_PP " cable to low volume waste streams
is int ded to reguirc that low volume waste strPani e
treated �� s h_
, as necessary, to comply with the pH limitation prior
to rtischarge. 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.
(202-3n2-7165)
Sincerely,
/11�s!
Dennis Ruddy
Project Officer
F.fflucrit Guidelines Division
U

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
In reply refar to -
3EN21
REGION III
6Tm ANO WALNUT STREETS
PHiLADELPHIA. PENNSYLVANIA 19106
March 10, 1976
Mr. Junes Loag -
Power Plant Services Section
Philadelphia Electric Company
2301 Market Street
Philadelphia, Pennsylvania 19101
Dear Mr. Long:
4J ,.H. LONG
1
9 WING
This is in response to your ascond progrezc report subaitted February 10,
1976 for thr, Chester Generating Station (PA 0011614), in which you propos,o to d.
charge boiler blowdown, zeolite aoftencr regenerates, and evaporator b1cmdown tc
the rereiving stream without pH neutralization. Please be advised that
40C'rit Part 423.32(b) (1) requires the pH of all discharges from power pUnts
(except once -through cooling water) to be in the.range of 6 - 9. Ecoacnics
were considered prior to the development of the final guideline limitatioac,
therefore the expense you have cited as being associated with neutralizing thew
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 situatica with respect to neutralizing these effluent
streams. It was decided that waste- stream could be combined with cooling water
for the so a purvose D neu a as Ion as e n was
the H
ran a of 6 2'his-o o not inconsi with ufdeline re ce-
ments. II sFouBe noted however, ,that pollutant parameters other -than pH wil:
6—e Timited and moit3tor r or to Fie com-bEa[3oa'oF—a part cu ar waste source
catetory with cooling Vaatar.
I trust this will enable you to complete your treatment plans. If there
are any questions, pleiss don't hesitate to contact me at 215 597-3689.
Sincerely yours
Bruce P.Smith
Delmarva -D.C. Section

Consolidated Edison Company of New York, Inc.
4 Irving Ptace..New York, N.Y. IW03
September 21, 1984
Mr. Dennis Ruddy (WH -552)
Project Offices
Effluent Guidelines Division
U.S. Environmental Protection Agency
401 M Street S.W.
Washington D.C. 20460
Re: pH Limits on Power Plant
Internal Waste Streams
Dear Mr, Ruddy:
Enclosed"..for, your - inforMatiQri ., is -a -'co
comments to t3YSDEC concerning proposed pH limits and monitorring
requirements specified in the draft renewal permit
Edison's Waterside Statifor Can
on. These comments expand upon Con
Edison's position concerning pH limits on internal waste
as expressed during our August streams,
10 meeting and detailed in previ-
ous correspondence. (In particular, see p.5, paragraph 2,
section 3(a)(5), section 3(b) and section 3(c) for new/expanded
arguments).
If you have any questions, please contact me at (212)
460-2522, We look forward to further discussions with you
concerning this issue.
Very truly yours,
Harry H. Cohen
Senior Environmental Engineer
Water & Waste Management
/gP
Attachment
cc: Mr. J. William Jordan (EN -336)
Chief
NPDES Technical Support Branch
U.S. Environmental Protection Agency
401 M Street S.W.
Washington D.C. 20460
1

j 1.
Y
�. '�H eFeauiremer.ts (See Ef
..
..uert iL'litaticr.s ar.d *�"c^i_tcrir_g
vui,e�errs, p. 2). -
DEC prcvoses tr mairtair• the current FP 1_r; tPti_cr, (range oL
6.0-9.05 For Lis charge 00:. and delete the current 6.0_9,0 nF_
limitation For Discharge 001. DEC also proposes tc add af3
limztcticns (6.0-9.0) `cr internal waste streams 00?z
(boiler blowdo%-n) , COib (1•'aterside ?.a. i demineraliter
recer,eratier. wastes) , 001c (-.rico ar.0 eouipr�er,t drainage)
anal 0022 (1 aters_de F -o.2 demineralizer reCer;eratior. wastes) .
Ir addition, DEC has Arepcsed to delete p1= mo-nitcrirg
requiremer.rs at DischzT�e 001, revise the p?' r cnitor_r.€
freauencv ;o_ DisCharge 602 from twice , eekl!. to weekly are,
add vE monitoring xecuirem.ents rcr waste streams 001a
(weekly grab), 001b ar_e- 002a (crab before each batch
eischarge) ar.d 001c ( twice month.L.*j . DEC pr�pcses 'that a'!
neva/re�-ised effluent li.mitct;cr,s and mor -it- recLiremer.ts
take exsect i .eciatel; upor. the effective date of the
renewal permit.
�S
j 1.
Y
�. '�H eFeauiremer.ts (See Ef
..
..uert iL'litaticr.s ar.d *�"c^i_tcrir_g
vui,e�errs, p. 2). -
DEC prcvoses tr mairtair• the current FP 1_r; tPti_cr, (range oL
6.0-9.05 For Lis charge 00:. and delete the current 6.0_9,0 nF_
limitation For Discharge 001. DEC also proposes tc add af3
limztcticns (6.0-9.0) `cr internal waste streams 00?z
(boiler blowdo%-n) , COib (1•'aterside ?.a. i demineraliter
recer,eratier. wastes) , 001c (-.rico ar.0 eouipr�er,t drainage)
anal 0022 (1 aters_de F -o.2 demineralizer reCer;eratior. wastes) .
Ir addition, DEC has Arepcsed to delete p1= mo-nitcrirg
requiremer.rs at DischzT�e 001, revise the p?' r cnitor_r.€
freauencv ;o_ DisCharge 602 from twice , eekl!. to weekly are,
add vE monitoring xecuirem.ents rcr waste streams 001a
(weekly grab), 001b ar_e- 002a (crab before each batch
eischarge) ar.d 001c ( twice month.L.*j . DEC pr�pcses 'that a'!
neva/re�-ised effluent li.mitct;cr,s and mor -it- recLiremer.ts
take exsect i .eciatel; upor. the effective date of the
renewal permit.

Cor. Edison's pcsition with regard to DEC's proposed pH
requirements is su=.nta.rized below:
o Efflzert l;arit2ticr,s and/or r°onitorirg reeuirements for pH
internal waste streams 001a, OOIb, OCIc, 002a or any
other i.ntery-al waste stream cannot legally be imposed ir.
the final permit. _
o There is no environmental justificati•-on for a pH limit on
internal waste streams. Effluent limits on internal waste
streams are redundant and unnecessary since the Currant pH
of 6.0-•9.0 at the point cf discharge to the public
receiving water vrovides adequate rrctectior: of water
quality. Furthermore, a PF limit of 6.0-9.0 has beer.
deemed acceptable by DEC at the point of discharge,
o The costs to achieve a pi; limit of 6.0-9.0 on internal
waste streams wculd be wholly disproportionate to anv
limited effluent reducticr and' environmental benefits to
be derived.
o Even if it were eventually determined that pH I;t:its ms,-
Legally be imposed far waste streams. -001a, OOlb, OOlc and
002a (which for the reasons set' forth in- these ce='gents
cannot Iar„full be the case) , in order to achi�,
eve
corsistenc- with the limit of 6.0-9.0 at rischar.ep 001,
such limitat-OPs must be less stringent than a Targe of
6.0-9.0 (applied at the paint of discharge), '_P. order to
take _`u11w iP_to account p adjustwent w=thin the
discharge tur.nels ; ar_d
C P_ cotrpli ance schedule to meet pF limits on interr.�l waste
streams reed net be provided if sucl-: limits are not
ultimatei,r 4 -u ---posed, Even if it were,,
determized that P. ].entual ;*
p _wits Cr.cirLF=r.2.1 *•;2.ste :,creams Ma�•
legall.• be imposed, a reascr.•able cctpliance schedule must
be previced to ir,stall equipment r_ecesszry to aCh-ZeVe
such lircitations before they become Pffectit*e.
The support nor this pc
sition is as fellcws:
(a)
Effluent T ami taticr.s
and/Or :.cr.itorir. 1?ec
it lr:terna krc.ste treams u a uixeQe_,t, for fli?
e , L C, to Or Anv
Cthe_intE'--r o1 T�iaste Stream Carr_ct Le.eal'.•: be Iuposed
(1) The Clear. stater Aar_ ?._mits the authority Under Section
402 to cop -trolling the additior. c=am pollutants to
ngzb1.e waters through point source discharges
(Ser -tiers 301 and 403 C.r.d defiritior_s specified in
Secticr 50`', Paragraphs (1),(7),(11),(12) and -(16))
Based cr. those sections, eff'luPr.t lim:taticrs can only
be applied at the poirt the effluent enters thP.
rece_' ng waters, except by the consent o_`
remittee. Therefore th the
e point c= c'ischargo into

navigable waters fcr Discharges 001 and 002 (are 003)
at the Statticn is at the confluence of the end of the
discharge_ tur_n_els and the East Fiver.
(2) EPA's NIMS (Deccrsciidated) Regulaticr_s (40 CFR 122)
essentially track the authority specified under Section.
402 and require effluent 2imit2-ticns to be set at the
point of discharge to navigable waters. Section
122.45(a) states that all permit effluent limitaticr.s
shall be established for "each outfall or cischarge
point of the permitted fac;.l'it.r" px.cept as otherwise
provided in Section 122.45(1). Section 122.45(1)(1)
states that limits on interval waste streams main be
imposed in encepticral cases and crly if limitations at
the cutfall are impractical or infeasible. Secticr.
122.45(1) (2) states that 14r -its on irternal waste
streaws tray be imposed only whey the Fact Sheet under
Section 4C CFP_ 124.56 sets `orth the en.cepticral
circumstances which make .uch 14Mit,itions necessar-r,
such as when the final discharge -point is inaccessible,
the wastes are so diluted as to make tnonitorir.g
itrpracticeble or the interference of pollutants at the
point of discY:2rge `taeuld make detection. or aralysi.s
impracticable. Both Sections 122.45• arid 124.56 are
applicable to State progray.s.
Based on these regulations, there can be no exceptior_al
circumstance Justi_`ication for impesition cf pu Limits
and/or monitoring requirements or, internal waste
streams unless the `incl. discharge point is
inaccessible for samplir:g. Yon.itoring (der_actien «r_d
analysis) for PP: (unlike pol-lutants measured in te.rr.s
of mass or concer.tration, such as heavy meta.? s) is r:et
impractical at the point of eischaree due to dilution
or interference. Bused cn the eistincticn bet -ween the
nature'and monitoring of pu and other pc?lutarts, Con
Edison has accepted irterral limits or_ other pel?utants
ir- some cases (even thcugh kze bQl'_eve that such limits
cannot le9 P_I? be itrpcseC based cr. the Clean Water Act
and State Ervirormer.tel Conser,rr.tien. raw) since in
these cases we recognize the impractic2ji`, of
deterrir-irg cotrpl iar.ce with Pfrluent '_imitations _`or
such pcll.utants at the xinal discharge (see Section 2.
of these comments). Such impracticality, h.owe-:Pr, does
not appl_ tc PP.
regard to rhe euas*_icr- of sampli:-g points, pF,
samples for Visci-erges 001 arc' 002 are c-urre nt:.-, taker_
it the discharge plume off the dcck rather than
directly ir. the dischargetunnels, since p'l,, s_cal
access to the turrels is currnntlxr unavailable i.e. the
discharge tur.r-el s ter -m -irate under the FDR Drive, about
60 feet 'prem the end of the dock, However, Ccr. Edison.
will create sampi ir,.g access points ir_ the Discharge 001

and 002 -discharge tunnels by June 1, 1985, or by the
beginning of the 1985 chlorination seascr, at Waterside,
whichever :.s later, as part of our ch'crine comnliardce
prcgram (aee ccuments ccr.,cerr..ing proposed ch'_crzn_e
requirements, Section_ 4(c)). Therefore, there is no
LustiTication for internal waste stream pF limits based
or, Secticr. 122.4-4.
(3) Title 8, Article 17 of the New York State Environmental
Cons ervatior. Leos (ECL) requires permits for the
discharge of pollutants from ary cutlet or point source
to the war_Prs of the state (Section I7-0803). The ECL
clearly limits DEC's autherit- to controlling
pollutants at the point such effluents enter the
receiving waters (Sections 17-0803, 17-0809 and the
definitions specifiedii, 17-0105, paragraphs
(2),(11),(15) and (16)). This limitation is rein -forced
by the SPDES regulations implementing the ECL (6 FYCF.R
Parts 750-757), Although we believe that the ECI.,
limits DEG's authority to impose effluent limits at the
final discharge, Ccn Edison has accepted, and will
continue to accept internal waste stream limits for
pollutants other than pH where we believe compliance
mcni.toring at the final discharge point is iu:practical ,
the limitaticns are reasonable and not more stringer t
than required by appropriate regulations. This is
clearly not the case for pR.
(4) EPA Best Practicable Technology (EPT) regulations limit
the pF of all discharies frog steam electric power
plants, except once thrcugh cooling eater, to a range
of 6.0-9.0 (40 CFR 423.12(b)(1); emphasis -zdcled).
EPA.'-- current Effluent Limitation ruieel=r:es fcr pH (47
FR 52303, "'ovember 19, 1982) are identical to tizose
contained in the init--a??., promulgated Gu'_del res
published ir, the Federal FRQister cn October ^, 1974
(39 eP. 36156). in both the ori€:nal and revised
Guidelines, r.0 PIS liritatior.s are evplicitl_T placed cr,
any internal waste streams. Based on the cefinitior�s
specified in the Clear. 'plater Act, trip EPA1,u;tation o_`.
6.0-9.0 would apply on! -7 at the cutlets of the
discharge tunnels to the East D?Ver and not tc ar.=-
:-terral waste stream. '
F -v 1PttPr dated May 3, !nS4 (artachsrent to E'.chirit 1)
Cor. Edison fcrmal'_,T reauested that the C.S.
Envircrmental Protection A gprc-v (EPA) clarify its BPT
ar_d internal waste stream regul ations as they apply to
PH. At a meeting beI-cn August 10, 1964 between Con
Edison and. EPA., the Age-* stated that it *could ta.`:e
E.beut one corth to re` -Dew- the rulet:G,cirg -record. and
ir;fcrr Can Edison and DEC of its detertination.
f � . _ 'U- 7— cl,_, 'PtPd December 13, 1982, DEC states

that internal waste stream monitoring is proposed for
specific low volume wastewaters since compliar_cP with
applicatrle limitations cannot be determined at the
final discharge. For the following reasons, this
explanation dces not satisfy Federal (40 CFR 124.56)
and. State (6 NYCFD 753.3) regulations, which require
that Fact Sheets set forth the legal and technical
basis of proposed limitati or.s :
(a) The Fact Sheet does not specifically address the
rationale for the proposed pH limits. ''r. fact, it
cannot be deterrri.r.ed from the Fact Sheer_ to which
waste streams Pinel pollutantE the ezp_ar.ation
pro-ided in the Fact Sheet applies;
(b) The Fact Sheet Coes not specif; whether the
proposed pH limits are based' on EPA's Guidelines
for Steam Electric Power Plants or DEC's ?est
Professional Judgement (BPJ) determination of Best
Practicable Technolog.- (BPT) or Best Converntional
Technology (BCT), or any other basis;
1. T_f the proposed limit is based on EPA's
Guidelines, it does rot specify whether DFC
interprets the 6.0-9.0 BPT pH -14 -Mit to apply to
internal waste streams (are- if so, the rpaso s
for that in..tepretation) or to fir_al discharges;
2. If the orovosed 1` -mit is based or. BPJ, 'it toes
not address the factors specified in Section 304
of the Clear. Water Act or 40 ClEM. 125.3 (See
Paragraph 3.(d) of these comments);
(c) The Fact Sheet does not specify which sections of
the Clear. Water Act srd State Ervirenmental
Ccrservation Law provide rEC with the authority to
impose ir.terr_al waste stream limits for pF. Ncr
does it specif.? the sections of EPA and DEC
regulatior^s which authcri_ze such 14-rc=ts; arcr
(d) The Fact Sheet does not specify trhich of the
e-certicnal circumstances speci.ried in 40 CFR
1;22.45(10, it an-, it relied or. tc reach the stated
ccrc?usior. that comp'_ Prop with the 6.0-9.0 pr
l.ir itaticn cannot be dete�e;ined by rronitoring at
the final discharge.
(b) There is Yo Envi rcrmer.tal Justi`;cati on for rF liudts cr_
�
rterna' Weter Creams
The current pH limitation of 6.0-9.0 at Pi.scharaes 001 are
CO? affords adequate prctectior_ of public receivire water
eualit'. A Fu limit of 6.0-9.0 at the pcint of discharg-
Gt?$ deemed acceptable by F t-_ 8egion If (and DEC b-, its

Section 401 Certification) in the initial discharge permit
issued by F,egion ll on November 30, 1974, as well as by DEC
(and Region II ir. its overview capacity) in the rer+ews
pe --mit issued b� DEC on ?ul 1, 1980. Beth the inir_,al and
renewal permits were based on EPA's Erfluent Guiaelines
promulgated on October 8, 1974 and were to bare included any
more stringent Nater cua?ity-based'— requiren..erts. Since
applicable Effluent Guidelines fqr pH have not charged since
initial permit issuance and DEC has not shown that a final
discharge pF within the range of 6.0-9.0 has caused or wil'-
cause any adverse environmental impacts, there is no basis
for imposition of more stringent pH limitations in the
renewal permit. In addition, b,? proposing to maintain_ the
current 6.0-9.0 pH limitation for Discharge 002, DEC has
deemed that range acceptable at the point of discharge.
Furthermore, installation of a waste neutral inn tion system,
which would by required to meet the proposed limits, would
result in the addition of significart amounts of
neutralizing chemicals (acid/caustic), thereby increasing
the amount of pollutants discharged.
(c) The Cost To Achieve Interna? taste Stream pF. Limits Is
'.�'hc_ v Itis rro crtzor.ate To The Eifluert Reduction Benerits
To Be Derive
The Waterside Statior. has two demineralization_ systems,
which are housed in separate buildings. In order to achieve
the proposed pH limits for demineralizer regeneration_ waste
streams (001b and 002a) ,, installation of two waste
neutralization systems would be required due to the physical
layout of the facility and the relatively large number of
regenerations performed (See SPIES Aprlicatior. Update for
more detailed information ccr_cerr.irg regeneration waste
streams). Each s -stem would consist of 1-2 large
reutrel_zatior. tanks, pumps, acid and caustic injection
systems, inst:um.entation and cortro_s ar_d 2n elaborate
piping system. Con Edisor. ccnservat;vel?estimates the
total capital cost of these s, -stems to be'$3-! m4llicr, a
reasonable estimate tcking into account the nature of the
faci li tv (prim.arily stem^. sendout), age of the facility, its
ph;rsi.cal lz;�cu* avid space limitations, and she re?ativel■-
large number of regereretior.s (due to steam sendout). ?`hese
costs would increase substantially if a pF limit of 6.0-9.0
is imposed for boiler blewdovv. (001a; and 0022 In current
permit) , Which tvpicG'_ y has a pE of 10-10.5. In additicr,
substar.t=ai operatin€ casts (Labor and chemica?s) Gvould be
incurred. These capital ,ard eperat;rg costs- would
ult wllat-e?-r be borne by Con Edison's steam' and electric
ratepayers.
As stated above, Con Edson believes that there is no
environmental justification for a pF limit of 6,0-9.0 or.
internal waste streams. Such limits would result in little,
r
4i anv, environmental benefits, which are wholly

disproportionate -to the costs that would be borne by Con
Edison and' its ratepayers. As specified above, such
requirements would, in fact, result ir_ the discharge or
increased aurourt of pollutants.
(c') if It I?ere Eventually To Be Determined That pR Livits :fav
Legally Be 2r_Desed For Inteiiial -Waste Streams .such
Limitations Mu sr a Less . trinsient t ar6.0-9.0
The existing pi? limits of 6.0-9.0 for Discharges 001 ar_d 002
reflect Best Practicable Control Technology Currently
Available (RPT) as defir_ed by EPA (40 CFR 423.1:(b)(1)). By
limiting the pH cf internal waste streams to that same
range, DEC is, in effect, proposing a limit more stringent
than BPT. Section 301(b)(2)(E) of the Clean Water Act
provides for more stringent limits than EPT for ph and other
contventional pollutants by application_ of the Rest
Conventional Pollutant Control Technolog,T (ECT). EPA has
deferred promulgation of LCT limitations for power plants
pending promulgation of a revised BCT methodology.
Therefore, any BCT limits imposed. in a power plant permit
must be developed on a case-by-case besis, pursuant to
Sector. 402(a)(1) of the Clean Water Act and Article 17,
Title 8 of the State Envirormental Conservation_ Lav,.
The proposed internal waste stream 1--mitatior_ of 6.0-9.0
e:ust accordingly be based or a case-by-case determination c.--
ECT
fECT by DEC. 'EPA regulations (40 CFR 1_?5.3(c)) allow the
impositior. of technology based limitations to the extent
EPA -promulgated effluent guidelines are inapplicable. Ir.
these cases, the permit issuing authority (DEC) is required
to apply the appropriate factors speci Jed ir. Sectio•. 304(b)
of the. Clear. Water Act. Fcr def:eLctPmer.t of BCT
limitations, the factors specified in Section 304(b)(4)(11)
must be applied. These factors include "the reasonableness
of the relationship between tho costs of attaining a
reduction in effluent and the effluent reduction benefits
derived, and the comparison of the cost and level of
reduction of such pollutant from publicly owr:ec treatment
works to the cost and leve'_ of reduction of such pollutants
`_rcm a class of category cf industrial source" and "the age
o` equipment ar_d facilities involved., the process employed,
the engineering aspects of the application of trarious t^pea
of control techr_iaues, process changes, nor -water quality
environmerta.l impacts (including energ,., requirements). �'
Case-by-case limits must also consi.deT the aporcpriate
technology for the applicant's industrial category anal any
ur.i cue factors' relating tc the facilit; (40 CFR
125.3(c)(2)). These Factors gust be considered. regardless
OF the permit issuing authorit:- (40 CFR 125.3 (c)).
On Y'ovember 13, 1982, EPA proposed to revise 40 CFR 124.56
and 40 CFR 125.3 to explicitly specify the statutcry and
�arYnr.q that crust be considered in settirg

case-by-case, gest Professional Judgement (BPJ) limits and.,
the information that must be ircluded in the Fact Sheet (47
YR 52072).,_ The preamble to the proposed regulations state's,
that "Section 125.3(c)(2) already requires permit writers to
consider `statutory `actors" in issuing gPJ permits, E'o
these changes simply clarify an existir_g requirement." (47
re, 52080). The propcsed regulaticns4r therefore, would make
explicit what is already required, namely the application of
the statutory factors and any other factors considered in
the determination of BPJ limits and the inclusion: In the
Fact Sheet of any analysis of the appl_cation of these
factors ar.d identification of any guidar_ce cr other
documents relied upon in setting the limits.
DEC has not provided Con Edison with ar.y documentation of
its consideration, of the factors specified in Section
304(b)(4)(B) and 40 CFR 125.3(c)(2) in its development of
the proposed ECT limits for pF. Therefore, DEC ca.rnot at
this time impose BCT limitatiors more stringent than 'EFT.
Even if it should ultimately be determined that DEC may
impose PH limits on internal' waste streams, which for the
reasons set forth hereiii. we submit it cannot Iawfull„ eto,
then such limitatiop-s must be less stringent than. 6.0-197.0 so
as not to be in conflict with a 6.0-9.0 limitation at the
point of discharge. Otherwise, the internal limitations
vculd be more stringent that FnT and must be Justified
taking into account the factors specified above.
(e) Even If it Were Eventuall• To Be-Determired That pF Limits
Mat 1.eQ2_1'* i3e ITm Ose � or-pterna ?.este wtrea r P_
Reasonable Compliance Sche ule rust e Provided
if it were to eventually* be determi'red that PH limits may
legally be imposed on' internal waste streams and such
limitations were Imposed, a reasonable schedule of
compliance would need to be provided in order to perr;it
procuremer.•t and installation of r._ecessa.r-- equipment before
such limits become effective.
DEC's propcsed compliance deadlir_e (effective date of the
rerewal permit) is both arbitrary arc impossible to achieve.
Although DEC has riot provided itE rationale fcr the proposed
compliance deed'_ire, we presume that it was based cr! th; BCT
deadi_re cf Jul,? 1, 1984 specifies' in Sec*icr. 301 (b) (.2) (E)
sYf the CIPa n 17ater Act. ucwever, s_r.ce DEC's prcposed
limits carr_ct ? eg?ll.» be imposed ur.rr _ PCT as d_5CL5Sed
pre-�iously, the Ju1,J 1 , 1984 deadline eces not apply.
?f theproposed ur.reascr_eble and impracticable ccmp liarce
deadline we_rP to be eventually imposed, Cor_ Edison would
affair!;,, be put in the ur_terable Position of immediately
violatir_g the peg. nit. For purposes of framing the issues
=or consideration in a hearing, ar,y permit issued b -T PEC

containing pN limits on internal waste streams should
contain a realistic compliance schedule, to be subsequently
agreed upon-, which would er_cor:pass time periods r+ecessar ,
for the procurement and installation of necessary equiprer.t
(f) Monit_orinz P.equiremerts
Monitoring requirements for pN cannot legally be imposed for
ir_terral waste steams for the reasons stated herein. If it
were evertuall.? to be detert:_ned that pH monitoring
recuirements ma- legally be imposed on internal wastes
streams, moni-cring reauirerrents for those waste streams
should not be required pr'cr to a realistic comp].iar.ce
deadline eventuall- agreed uper (see paragraph (e) abo-%re) ,
since the limitations would not be effective until that
tire. We cannot currently comDly with the proposed
requirement of taking grab samples before each batch
discharge of demineralizer regeneration wastes (001b and
002a), since there is no provision for holding up these
wastes prior to discharge. Even if neutralization s,,-,stems
installed, this proposed requirement may be
impracticable, i f the sv_ ster.s are designed for
semi -continuous operation. in which, when the effluent is
within the set pH range, discharge may occur mann times over
a regeneraticr cycle.
In summarv, effluent limitaticns and monitoring reau'-Yements
nor pH should +not be imposed for internal waste strews for the
reasons specified above. The only pH limits that me -,,be imposed
are the current BPT permit limitations of 6.0-9.0 at Discharges
001 and 002 (and 003). This approach would be consistent with
that recommended by DEC in its Division_ of Water Guidance
memorandum No. 04-1;-33- ( "EPJ :.ethodologi es - Guidance for the
Application of Pest Professional Judgement (BP.-,) in DPte=.inir_g
SUES Uneitions," dated April 1983) , which states (Section
viil.F. ) 1.
'l-,'ith rP6ard to conventi ona7Fc+__�.t�rt_l 1 i _ C
, the Department
Will generally consider BPT z.r. acceptable level of
control, unless e!fluer.t guidelines or vatpr quality
necessitate more stringent control."
Since erfluenr gL 2elines mandate a pP limit of 6.0-9.0 at the
Point cr discharge and water cz-,li ,,;7 has rot been she ar to
*iecessitate an,. incre stringent limits, the current limits are
s.pprcpr=ate and should by fizir_ta_ned. DEC mai, not impose a
Particular techrclogy =cr rreetire SPI -ES 1 im'_ts . ' There=oze , Ccr
Ediscn should be free to meet those limitations by the method of
ou- choice.
Ever. if DEC could legall- impose pH limitat ons for internal
waste strealns at this facility, s compliance schedule would be
required to Pch4eve such limitations. in addition,
notwithstardir.e the legal arguments against impositicr. of pF

4.
h
f
requirements for inters!
legal and technical
waste
basis,
streams, DEC bust provide the
dccumer-tation,
-for any
such
including any supporting
reeuiremerts prier to their
establishment--;r
a final pe=it.
If-such ratio:-ale is e,7pntua'_?;�
prcvided, Car
evaluaticn and
Edison Trust
submission
be given a reasonable oprc_runity for
of
ccmments.
4.
h