Text

Environmental Assessment and Finding of No Significant Impact Related to a Requested Increase in Ultimate Heat Sink Temperature
	ML22159A174
Person / Time
Site:	Braidwood
Issue date:	07/15/2022
From:	Joel Wiebe; Plant Licensing Branch III
To:	Rhoades D; Constellation Energy Generation, Constellation Nuclear
	Wiebe J
References
	EPID L 2022 LLA 0082, NRC-2022-0141
	Download: ML22159A174 (24)
	v • d • e

July 15, 2022

Mr. David P. Rhoades Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Officer Constellation Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

BRAIDWOOD STATION, UNITS 1 AND 2 - ENVIRONMENTAL ASSES SMENT AND FINDING OF NO SIGNIFICANT IMPACT RELATED TO A REQUESTED INCREASE IN ULTIMATE HEAT SINK TEMPERATURE (EPID L-2022-LLA-0082)

Dear Mr. Hanson:

Enclosed is a copy of the Environmental Assessment and Finding of No Significant Impact related to your application for amendment dated June 3, 2022. T he proposed amendment would raise the maximum ultimate heat sink temperature from 102 degre es Fahrenheit (°F) to 102.8 °F.

The assessment is being forwarded to the Office of the Federal Register for publication. If you have questions contact me at Joel.Wiebe@nrc.gov or 301-415-6606.

Sincerely,

/RA/

Joel S. Wiebe, Senior Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Docket Nos. 50-456 and 50-457

Enclosure:

Environmental Assessment

cc: Listserv

ENCLOSURE

FEDERAL REGISTER NOTICE

[7590-01-P]

NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-456 and 50-457; NRC-2022-0141]

Constellation Energy Generation, LLC;

Braidwood Station, Units 1 and 2

AGENCY: Nuclear Regulatory Commission.

ACTION: Environmental assessment and finding of no significant impact; issuance.

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) is considering i ssuance

of amendments to Renewed Facility Operating License Nos. NPF-72 and NPF-77, which

authorize Constellation Energy Generation, LLC, (licensee) to o perate Braidwood

Station (Braidwood), Units 1 and 2. The proposed amendments w ould change

Technical Specification (TS) Surveillance Requirement (SR) 3.7. 9.2 to allow an ultimate

heat sink (UHS) temperature of less than or equal to 102.8 degrees Fahrenheit (°F)

through September 30, 2022.

DATES: The environmental assessment and finding of no significant im pact referenced

in this document is available on [INSERT DATE OF PUBLICATION IN THE FEDERAL

REGISTER].

ADDRESSES: Please refer to Docket ID NRC-2022-0141 when contacting the NRC

about the availability of information regarding this document. You may obtain publicly

available information related to this document using any of the following methods:

Federal Rulemaking Website: Go to https://www.regulations.gov and

search for Docket ID NRC-2022-0141. Address questions about Docket IDs in

Regulations.gov to Stacy Schumann; telephone: 301-415-0624; em ail:

Stacy.Schumann@nrc.gov. For technical questions, contact the i ndividual listed in the

For Further Information Contact section of this document.

NRCs Agencywide Documents Access and Management System

(ADAMS): You may obtain publicly available documents online in the ADA MS Public

Documents collection at https://www.nrc.gov/reading-rm/adams.ht ml. To begin the

search, select Begin Web-based ADAMS Search. For problems with ADAMS, please

contact the NRCs Public Document Room (PDR) reference staff at 1-800-397-4209,

301-415-4737, or by email to PDR.Resource@nrc.gov. For the con venience of the

reader, instructions about obtaining materials referenced in this document are provided

in the Availability of Documents section.

NRCs PDR: You may examine and purchase copies of public documen ts,

by appointment, at the NRCs PDR, Room P1 B35, One White Flint North, 11555

Rockville Pike, Rockville, Maryland 20852. To make an appointm ent to visit the PDR,

please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-

4737, between 8:00 a.m. and 4:00 p.m. Eastern Time (ET), Monday through Friday,

except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Joel S. Wiebe, Office of Nuclear Reactor

Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001,

telephone: 301-415-6606, email: Joel.Wiebe@nrc.gov.

SUPPLEMENTARY INFORMATION:

I. Introduction

The NRC is considering issuance of amendment s to Renewed Facility Operating

License Nos. NPF-72 and NPF-77, which authorize Constellation E nergy Generation,

LLC, (Constellation) to operate Braidwood Station, Unit Nos. 1 and 2, located in Will

County, Illinois. Constellation submitted its license amendmen t request in accordance

with section 50.90 of title 10 of the Code of Federal Regulation (10 CFR), by letter dated

June 3, 2022. If approved, the license amendments would revise TS SR in TS 3.7.9.2 to

2 allow a temporary increase in the allowable UHS average tempera ture of less than or

equal to () 102.8°F (39.3 degrees Celsius (°C)) through Septem ber 30, 2022.

Therefore, as required by 10 CFR 50.21, the NRC performed an environmental

assessment (EA). Based on the results of the EA that follows, the NRC has determined

not to prepare an environmental impact statement for the propos ed amendments and is

issuing a finding of no significant impact (FONSI).

II. Environmental Assessment

Description of the Proposed Action

The proposed action would revise the Braidwood TS to allow a temporary

increase in the allowable average temperature of water withdraw n from the UHS and

supplied to the plant for cooling from 102°F (38.9°C) to 10 2.8°F (39.3°C) through

September 30, 2022. Specifically, the proposed action would revise TS SR 3.7.9.2,

which currently states, Verify average water temperature of UHS is 102.8°F until

September 30, 2021. After September 30, 2021, verify average w ater temperature of

UHS is 102°F to state Verify average water temperature of U HS is 102.8°F until

September 30, 2022. After September 30, 2022, verify average w ater temperature of

UHS is 102°F.

Under the current TS, if the average UHS temperature as measure d at the

discharge of the operating essential service water system pumps is greater than 102°F

(38.9°C), TS 3.7.9 Required Actions A.1 and A.2 would be entere d concurrently and

would require the licensee to place Braidwood in hot standby (M ode 3) within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months

and cold shutdown (Mode 5) within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The proposed actio n would allow

Braidwood to continue to operate during times when the UHS indi cated average water

temperature exceeds 102°F (38.9°C) but is less than or equal to 102.8°F (39.3°C)

through September 30, 2022. The current TSs UHS average water temperature limit of

3 102°F (38.9°C) would remain applicable to all other time period s beyond

September 30, 2022.

The proposed action is nearly identical to previously approved license

amendments that allowed for the average water temperature of th e UHS to be 102.8°F

until September 30, 2020, and September 30, 2021. The NRC issu ed EAs for the 2020

and 2021 UHS amendments in the Federal Register on September 10, 2020, (85 FR

55863) and July 7, 2021, (86 FR 35831) respectively. The NRC i ssued the amendments

on September 24, 2020, and July 13, 2021, respectively. The on ly difference between

the previously approved amendments to SR 3.7.9.2 and the propos ed action is that the

proposed action would replace 2020 or 2021 with 2022. Th e proposed action is in

accordance with the licensees application dated June 3, 2022.

Need for the Proposed Action

The licensee has requested the proposed amendments in connectio n with

historical meteorological and atmospheric conditions that have resulted in the TS UHS

temperature being challenged. These conditions included elevat ed air temperatures,

high humidity, and low wind speed. Specifically, from July 4, 2020, through July 9, 2020,

northern Illinois experienced high air temperatures and drought conditions, which caused

sustained elevated UHS temperatures. In response to these cond itions in 2020, the

licensee submitted license amendment requests contained in the licensees letter dated

July 15, 2020, as supplemented by letter dated August 14, 2020. The NRC

subsequently granted the licensees request in September 2020. A similar request was

granted by NRC letter dated July 13, 2021. In February of 2022, the license for

Braidwood Units 1 and 2 was transferred to Constellation by Exe lon Generation

Company, LLC (Exelon). Constellation projects that similar con ditions are likely this

year.

4 The proposed action would provide the licensee with operational flexibility until

September 30, 2022, during which continued high UHS temperature s are likely so that

the plant shutdown criteria specified in the TS are not trigger ed.

Plant Site and Environs

Braidwood is in Will County, Illinois approximately 50 miles (m i); 80 kilometers

(km) southwest of the Chicago Metropolitan Area and 20 mi (32 k m) south-southwest of

Joliet. The Kankakee River is approximately 5 mi (8 km) east o f the eastern site

boundary. An onsite 2,540-acre (ac); 1,030-hectare (ha) coolin g pond provides

condenser cooling. Cooling water is withdrawn from the pond th rough the lake screen

house, which is located at the north end of the pond. Heated w ater returns to the

cooling pond through a discharge canal west of the lake screen house intake that is

separated from the intake by a dike. The pond typically holds 22,300 acre-feet (27.5

million cubic meters) of water at any given time. The cooling pond includes both

"essential" and "non-essential" areas. The essential cooling p ond is the portion of the

cooling pond that serves as the UHS for emergency core cooling, and it consists of a 99

ac (40-ha) excavated area of the pond directly in front of the lake screen house. The

essential cooling pond's principal functions are to dissipate r esidual heat after reactor

shutdown and to dissipate heat after an accident. It is capabl e of supplying Braidwood's

cooling system with water for 30 days of station operation with out additional makeup

water. For clarity, use of the term "UHS" in this EA refers to the 99-ac (40-ha) essential

cooling pond, and use of the term "cooling pond" or "pond" desc ribes the entire 2,540-ac

(1,030-ha) area, which includes both the essential and non-esse ntial areas.

The cooling pond is part of the Mazonia-Braidwood State Fish an d Wildlife Area,

which encompasses the majority of the non-UHS area of the cooli ng pond as well as

Illinois Department of Natural Resources (IDNR) owned lands adj acent to the Braidwood

5 site to the south and southwest of the cooling pond. The licen see and the IDNR have

jointly managed the cooling pond as part of the Mazonia-Braidwo od State Fish and

Wildlife Area since 1991 pursuant to a long-term lease agreemen t. Under the terms of

the agreement, the public has access to the pond for fishing, w aterfowl hunting, fossil

collecting, and other recreational activities.

The cooling pond is a wastewater treatment works as defined by section 301.415

of Title 35 of the Illinois Administrative Code (35 IAC 301.415 ). Under this definition, the

cooling pond is not considered waters of the State under Illino is Administrative Code

(35 IAC 301.440) or waters of the United States under the Feder al Clean Water Act

(40 CFR 230.3(s)), and so the cooling pond is not subject to St ate water quality

standards. The cooling pond can be characterized as a managed ecosystem where

IDNR fish stocking and other human activities primarily influen ce the species

composition and population dynamics.

Since the beginning of the lease agreement between the licensee and IDNR, the

IDNR has stocked the cooling pond with a variety of game fish, including largemouth

bass (Micropterus salmoides), smallmouth bass (M. dolomieu), bl ue catfish (Ictalurus

furcatus), striped bass (Morone saxatilis), crappie (Pomoxis sp p.), walleye (Sander

vitreum), and tiger muskellunge (Esox masquinongy x lucius). I DNR performs annual

surveys to determine which fish to stock based on fishermen pre ferences, fish

abundance, different species' tolerance to warm waters, predato r and prey dynamics,

and other factors. Because of the warm water temperatures expe rienced in the summer

months, introductions of warm-water species, such as largemouth bass and blue catfish,

have been more successful than introductions of cool-water spec ies, such as walleye

and tiger muskellunge. Since annual surveys began in 1980, IDN R has collected 47

species in the cooling pond. In recent years, bluegill (Lepomi s macrochirus), channel

6 catfish (Ictalurus punctatus), threadfin shad (Dorosoma petenen se), and common carp

(Cyprinus carpio) have been among the most abundant species in the cooling pond.

Gizzard shad (Dorosoma cepedianum), one of the most frequently affected species

during periods of elevated pond temperatures, have decreased in abundance

dramatically in recent years, while bluegills, which can tolera te high temperatures with

relatively high survival rates, have noticeably increased in re lative abundance. IDNR

stocked warm water game species, such as largemouth bass and bl ue catfish, continue

to persist in small numbers, while cooler water stocked species, such as walleye and

tiger muskellunge, no longer appear in IDNR survey collections. No federally listed

species or designated critical habitats protected under the End angered Species Act

(ESA) occur within or near the cooling pond.

The Kankakee River serves as the source of makeup water for the cooling pond.

The river also receives continuous blowdown from the cooling po nd. Water is withdrawn

from a small river screen house located on the Kankakee River, and liquid effluents from

Braidwood are discharged into the cooling pond blowdown line, w hich subsequently

discharges into the Kankakee River.

The plant site and environs are described in greater detail in Chapter 3 of the

NRC's November 2015 Generic Environmental Impact Statement for License Renewal of

Nuclear Plants: Regarding Braidwood Station, Units 1 and 2, Fi nal Report (NUREG

1437, Supplement 55) (herein referred to as the "Braidwood FSEI S" (Final Supplemental

Environment Impact Statement)). Figure 3-5 on pages 3-7 of the Braidwood FSEIS

depicts the Braidwood plant layout, and Figure 3-4 on pages 3-6 depicts the cooling

pond, including the portion of the pond that constitutes the es sential cooling pond (or

UHS) and the blowdown line to the Kankakee River.

7 Environmental Impacts of the Proposed Action

Regarding radiological impacts, the proposed action would not r esult in any

changes in the types of radioactive effluents that may be relea sed from the plant offsite.

No significant increase in the amount of any radioactive efflue nt released offsite or

significant increase in occupational or public radiation exposu re is expected from the

proposed action. Separate from this EA, the NRC staff is evalu ating the licensee's

safety analyses of the potential radiological consequences of a n accident that may result

from the proposed action. The results of the NRC staff's safet y analysis will be

documented in a safety evaluation (SE). If the NRC staff concl udes in the SE that all

pertinent regulatory requirements related to radiological efflu ents are met by the

proposed UHS temperature limit increase, then the proposed acti on would result in no

significant radiological impact to the environment. The NRC st aff's SE will be issued

with the license amendments, if approved by the NRC. If the NR C staff concludes that

all pertinent regulatory requirements are not met by the propos ed UHS temperature limit

increase, the requested amendment would not be issued.

Regarding potential nonradiologica l impacts, temporarily raising the maximum

allowable UHS temperature from 102°F (38.9°C) to 102.8°F (3 9.3°C) could cause

increased cooling pond water temperatures until September 30, 2 022. Because the

proposed action would not affect Braidwood's licensed thermal p ower level, the

temperature rise across the c ondensers as cooling water travels through the cooling

system would remain constant. Thus, if water in the UHS were t o rise to 102.8°F

(39.3°C), heated water returning to the cooling pond through th e discharge canal, which

lies west of the river screen house, would also experience a co rresponding 0.8°F (0.4°C)

increase. That additional heat load would dissipate across som e thermal gradient as

discharged water travels down the discharge canal and through t he 99-ac (40-ha) UHS.

8 Fish kills are likely to occur when cooling pond temperatures r ise above 95°F (35°C), the

temperature at which most fish in the cooling pond are thermall y stressed. For example,

section 3.7.4 of the Braidwood FSEIS describes six fish kill ev ents for the period of 2001

through 2015. The fish kill events, which occurred in July 200 1, August 2001, June

2005, August 2007, June 2009, and July 2012, primarily affected threadfin shad and

gizzard shad, although bass, catfish, carp, and other game fish were also affected.

Reported peak temperatures in the cooling pond during these eve nts ranged from

98.4°F (36.9°C) to over 100°F (37.8°C), and each event resulted in the death of between

700 to as many as 10,000 fish. During the July 2012 event, coo ling pond temperatures

exceeded 100°F (37.8°C), which resulted in the death of approxi mately 3,000 gizzard

shad and 100 bass, catfish, and carp. This event coincided wit h the NRC's granting of

Enforcement Discretion to allow Braidwood to continue to operat e above the TS limit of

100°F (37.8°C). The IDNR attributed this event, as well as fo ur of the other fish kill

events, to high cooling pond temperatures resulting from Braidw ood operation.

Appendix B, section 4.1, of the Braidwood renewed facility oper ating licenses, requires

Constellation to report to the NRC the occurrence of unusual or important environmental

events, including fish kills, causally related to plant operati on. Since the issuance of the

Braidwood FSEIS in November 2015, the licensee has not reported any additional fish

kill events to the NRC. Although not causally related to plant operation, fish kills have

occurred since this time, the most recent of which occurred in August 2018 and July

2020.

In section 4.7.1.3 of the Braidwood FSEIS, the NRC staff conclu ded that thermal

impacts associated with continued operation of Braidwood during the license renewal

term would result in SMALL to MODERATE impacts to aquatic resou rces in the cooling

pond. MODERATE impacts would primarily be experienced by gizza rd shad and other

9 non-stocked and low-heat tolerant species. As part of its conc lusion, the NRC staff also

noted that because the cooling pond is a highly managed system, any cascading effects

that result from the loss of gizzard shad (such as reduction in prey for stocked species,

which in turn could affect those stocked species' populations) could be mitigated through

IDNR's annual stocking and continual management of the pond. A t that time, the UHS

TS limit was 100°F (37.8°C).

In 2016, the NRC granted license amendments that increased the allowable UHS

average water temperature TS limit from 100°F (37.8°C) to 102.0°F (38.9°C). In the

EA associated with these amendments, the NRC staff concluded th at increasing the TS

limit to 102.0°F (38.9°C) would have no significant environme ntal impacts, and the

NRC issued a FONSI with the EA.

In 2020 and 2021, the NRC granted license amendments that tempo rarily

increased the allowable UHS average water temperature TS limit from 102.0°F

(38.9°C) to 102.8°F (39.3°C) until September 30, 2020, and Se ptember 30, 2021,

respectively. In the EA associated with these amendments, the NRC staff concluded

that temporarily increasing the TS limit to 102.8°F (39.3°C) would have no significant

environmental impacts, and the NRC issued a FONSI with the EA.

The NRC staff finds that the proposed action would not result i n significant

impacts to aquatic resources in the cooling pond for the same r easons that the NRC

staff made this conclusion regarding the 2020 and 2021 amendmen ts. The staffs

justification for this conclusion follows.

The proposed increase in the allowable UHS average water temper ature limit by

0.8°F (0.4°C) would not increase the likelihood of a fish kill event attributable to high

cooling pond temperatures because the current TS limit for the UHS of 102.0°F (38.9°C)

already allows cooling pond temperatures above those at which m ost fish species are

10 thermally stressed (95°F (35°C)). In effect, if the UHS temper ature rises to the current

TS limit, fish within or near the discharge canal, within the f low path between the

discharge canal and UHS, or within the UHS itself would have al ready experienced

thermal stress and possibly died. Thus, an incremental increas e in the allowable UHS

water temperature by 0.8°F (0.4°C) and the corresponding temper ature increases within

and near the discharge canal and within the flow path between t he discharge canal and

UHS would not significantly affect the number of fish kill even ts experienced in the

cooling pond. Additionally, the proposed action would only inc rease the allowable UHS

average water temperature until September 30, 2022. Thus, any impacts to the aquatic

community of the cooling pond, if experienced, would be tempora ry in nature, and fish

populations would likely recover relatively quickly.

While the proposed action would not affect the likelihood of a fish kill event

occurring during periods when the average UHS water temperature approaches the TS

limit, the proposed action could increase the number of fish ki lled per high temperature

event. For fish with thermal tolerances at or near 95°F (35°C), there would likely be no

significant difference in the number of affected fish per high temperature event because,

as already stated, these fish would have already experienced th ermal stress and

possibly died, and the additional temperature increase would no t measurably affect the

mortality rate of these individuals. For fish with thermal tol erances above 95°F (35°C),

such as bluegill, increased mortality is possible, as described in this EA.

The available scientific literature provides conflicting inform ation as to whether

incremental temperature increases would cause a subsequent incr ease in mortality rates

of bluegill or other high-temperature-tolerant fish when temper atures exceed 100°F

(37.8°C). For instance, in laboratory studies, Banner and Van Arman (1973)

demonstrated 85 percent survival of juvenile bluegill after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of exposure to 98.6°F

11 (37.0°C) water for stock acclimated to 91.2°F (32.9°C). At 100.0°F (37.8°C), survival

decreased to 25 percent, and at 100.4°F (38.0°C) and 102.0°F (3 8.9°C), no individuals

survived. Even at one hour of exposure to 102.0°F (38.9°C) wat er, average survival was

relatively low at between 40 to 67.5 percent per replicate. Ho wever, in another

laboratory study, Cairns (1956 in Banner and Van Arman 1973) de monstrated that if

juvenile bluegill were acclimated to higher temperatures at a 3.6°F (2.0°C) increase per

day, individuals could tolerate water temperatures up to 102.6° F (39.2°C) with 80

percent survival after 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months of exposure.

Although these studies provide inconsistent thermal tolerance l imits, information

from past fish kill events indicates that Cairns' results bette r describe the cooling pond's

bluegill population because the licensee has not reported blueg ill as one of the species

that has been affected by past high temperature events. Thus, bluegills are likely

acclimating to temperature rises at a rate that allows those in dividuals to remain in high

temperature areas until temperatures decrease or that allows in dividuals time to seek

refuge in cooler areas of the pond. Alternately, if Banner and Van Arman's results were

more predictive, 75 percent or more of bluegill individuals in high temperature areas of

the cooling pond could be expected to die at temperatures appro aching or exceeding

100°F (37.8°C) for 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , and shorter exposure time would li kely result in the death of

some reduced percentage of bluegill individuals.

Under the proposed action, fish exposure to temperatures approa ching the

proposed UHS TS average water temperature limit of 102.8°F (39. 3°C) and those

exposed to the associated discharge, which would be 0.8°F (0.4° C) higher than under

the current TS limit, for at least one hour would result in obs ervable deaths. However,

as stated previously, the licensee has not reported bluegill as one of the species that has

been affected during past fish kills. Consequently, the NRC st aff assumes that bluegill

12 and other high-temperature-tolerant species in the cooling pond would experience

effects similar to those observed in Cairn's study. Based on C airn's results, the

proposed action's incremental and short-term increase of 0.8°F (0.4°C) could result in

the death of some additional high-temperature-tolerant individu als, especially in cases

where cooling pond temperatures r ise dramatically over a short period of time (more

than 3.6°F (2.0°C) in a 24-hour period).

Nonetheless, the discharge canal, flow path between the dischar ge canal and the

UHS, and the UHS itself is a small portion of the cooling pond. Thus, while the

incremental increase would likely increase the area over which cooling pond

temperatures would rise, most of the cooling pond would remain at tolerable

temperatures, and fish would be able to seek refuge in those co oler areas. Therefore,

only fish within or near the discharge canal, within the flow p ath between the discharge

canal and UHS, or within the UHS itself at the time of elevated temperatures would likely

be affected, and fish would experience such effects to lessenin g degrees over the

thermal gradient that extends from the discharge canal. This w ould not result in a

significant difference in the number of fish killed per high te mperature event resulting

from the proposed action when compared to current operations fo r those species with

thermal tolerances at or near 95°F (35°C) and an insignificant increase in the number of

individuals affected for species with thermal tolerances above 95°F (35°C), such as

bluegill. Additionally, the cooling pond is a managed ecosyste m in which fish stocking,

fishing pressure, and predator-prey relationships constitute th e primary population

pressures.

Fish populations affected by fish kills generally recover quick ly, and thus, fish kills

do not appear to significantly influence the fish community str ucture. This is

demonstrated by the fact that the species that are most often a ffected by high

13 temperature events (threadfin shad and gizzard shad) are also a mong the most

abundant species in the cooling pond. Managed species would co ntinue to be assessed

and stocked by the IDNR on an annual basis in accordance with t he lease agreement

between Constellation and IDNR. Continued stocking would mitig ate any minor effects

resulting from the proposed action.

Based on the foregoing analysis, the NRC staff concludes that the proposed

action would not result in significant impacts to aquatic resou rces in the cooling pond.

Some terrestrial species, such as birds or other wildlife, rely on fish or other aquatic

resources from the cooling pond as a source of food. The NRC s taff does not expect

any significant impacts to birds or other wildlife because, if a fish kill occurs, the number

of dead fish would be a small proportion of the total populatio n of fish in the cooling

pond. Furthermore, during fish kills, birds and other wildlife could consume many of the

floating, dead fish. Additionally, and as described previously, the NRC staff does not

expect that the proposed action would result in a significant d ifference in the number or

intensity of fish kill events or otherwise result in significan t impacts on aquatic resources

in the cooling pond.

With respect to water resources and ecological resources along and within the

Kankakee River, the Illinois Environmental Protection Agency im poses regulatory

controls on Braidwood's thermal effluent through Title 35, Envi ronmental Protection,

section 302, 'Water Quality Standards," of the Illinois Adminis trative Code (35 IAC 302)

and through the National Pollutant Discharge Elimination System (NPDES) permitting

process pursuant to the Clean Water Act. Section 302 of the Ill inois Administrative Code

stipulates that "[t]he maximum temperature rise shall not excee d 2.8°C (5°F) above

natural receiving water body temperatures," (35 IAC 302.211(d)) and that "[w]ater

temperature at representative locations in the main river shall at no time exceed 33.7°C

14 (93°F) from April through November and 17.7°C (63°F) in other m onths" (35 IAC

302.211(e)). Additional stipulations pertaining to the mixing zone further protect water

resources and biota from thermal effluents. The Braidwood NPDE S permit contains

special conditions that mirror these temperature requirements a nd that stipulate more

detailed temperature requirements at the edge of the mixing zon e. Under the proposed

action, Braidwood thermal effluent would continue to be limited by the Illinois

Administrative Code and the Braidwood NPDES permit to ensure th at Braidwood

operations do not create adverse effects on water resources or ecological resources

along or within the Kankakee River. Occasionally, the licensee has applied for a

provisional variance to allow higher-than-permitted temperature s at the edge of the

discharge mixing zone. For instance, Exelon, the license holde r at the time, applied for

and the IEPA granted one provisional variance in 2012 during a period of extremely

warm weather and little to no precipitation. Exelon reported n o fish kills or other events

to the IEPA or the NRC that would indicate adverse environmenta l effects resulting from

the provisional variance. The details of this provisional vari ance are described in section

4.7.1.3 of the Braidwood FSEIS.

Under the proposed action, Constellation would remain subject t o the regulatory

controls described in this notice. The NRC staff finds it reas onable to assume that

Constellation's continued compliance with, and the State's cont inued enforcement of, the

Illinois Administrative Code and the Braidwood NPDES permit wou ld ensure that

Kankakee River water and ecological resources are protected. F urther, the proposed

action would not alter the types or amounts of effluents being discharged to the river as

blowdown. Therefore, the NRC staff does not expect any signifi cant impacts to water

resources or ecological resources within and along the Kankakee River from temporarily

increasing the allowable UHS average water temperature TS limit.

15 With respect to federally list ed species, the NRC staff consulted with the U.S.

Fish and Wildlife Service (FWS) pursuant to section 7 of the ES A during its license

renewal environmental review for Braidwood. During that consul tation, the NRC staff

found that the sheepnose (Plethobasus cyphyus) and snuffbox (Ep ioblasma triquetra)

mussels had the potential to occur in the areas that would be d irectly or indirectly

affected by license renewal (i.e., the action area). In Septem ber 2015, Exelon

transmitted the results of a mussel survey to the NRC and FWS. The survey

documented the absence of federally listed mussels near the Bra idwood discharge site

in the Kankakee River. Based on this survey and other informat ion described in the

Braidwood FSEIS, the NRC concluded that the license renewal may affect, but is not

likely to adversely affect the sheepnose mussel, and the NRC determined that license

renewal would have no effect on the snuffbox mussel. The FWS c oncurred with the

NRC's "not likely to adversely affect" determination in a lette r dated October 20, 2015.

The results of the consultation are further summarized in the R ecord of Decision for

Braidwood license renewal.

As previously described, impacts of the proposed action would b e confined to the

cooling pond and would not affect water resources or ecological resources along and

within the Kankakee River. The NRCs previous ESA, section 7, consultation confirmed

that no federally listed aquatic species occur within or near t he cooling pond. The NRC

has not identified any information indicating the presence of f ederally listed species in

the area since that consultation concluded, and the FWS has not listed any new aquatic

species that may occur in the area since that time. The propos ed action would not result

in any disturbance or other impacts to terrestrial habitats, an d thus, no federally listed

terrestrial species would be affected. Accordingly, the NRC st aff concludes that the

proposed action would have no effect on federally listed specie s or designated critical

16 habitat. Consultation with the FWS regarding the proposed acti on is not necessary

because Federal agencies are not required to consult with the F WS if the agency

determines that an action will have no effect on listed species or critical habitat.

The NRC staff has identified no foreseeable land use, visual re source, noise, or

waste management impacts given that the proposed action would n ot result in any

physical changes to Braidwood facilities or equipment or change s any land uses on or

off site. The NRC staff has identified no air quality impacts given that the proposed

action would not result in air emissions beyond what would be e xperienced during

current operations. Additionally, there would be no socioecono mic, environmental

justice, or historic and cultural resource impacts associated w ith the proposed action

since no physical changes would occur beyond the site boundarie s and any impacts

would be limited to the cooling pond.

Based on the foregoing analysis, the NRC staff concludes that the proposed

action would have no significant environmental impacts.

Environmental Impacts of the Alternatives to the Proposed Action

As an alternative to the proposed action, the staff considered denial of the

proposed action (i.e., the no-action alternative). Environme ntal Impacts of the

Alternatives to the Proposed Action

As an alternative to the proposed action, the NRC staff conside red the denial of

the proposed action (i.e., the no action alternative). Denia l of the proposed action

would result in no changes to the current TS. Thus, under the proposed action, the

licensee would continue to be required to place Braidwood in ho t standby (Mode 3) if

average UHS water temperatures exceed 102°F (38.9°C) for the te mporary period of

July 2022 through September 2022. The no-action alternative wo uld result in no change

in current environmental conditions or impacts at Braidwood.

17 Alternative Use of Resources

There are no unresolved conflicts concerning alternative uses o f available

resources under the proposed action.

Agencies and Persons Consulted

No additional agencies or persons were consulted regarding the environmental

impact of the proposed action.

III. Finding of No Significant Impact

The NRC is considering issuing amendments for Renewed Facility Operating

License Nos. NPF-72 and NPF-77, issued to Constellation for ope ration of Braidwood

that would revise the TS for the plant to temporarily increase the allowable average

temperature of the UHS.

On the basis of the EA included in Section II and incorporated by reference in

this finding, the NRC concludes that the proposed action would not have significant

effects on the quality of the human environment. The NRC's eva luation considered

information provided in the licensee's application as well as t he NRC's independent

review of other relevant environmental documents.Section IV l ists the environmental

documents related to the proposed action and includes informati on on the availability of

these documents. Based on its finding, the NRC has decided not to prepare an

environmental impact statement for the proposed action.

This FONSI and other related environmental documents are availa ble for public

inspection and are accessible online in the ADAMS Public Docume nts collection at

https://www.nrc.gov/reading-rm/adams.html. Persons who do not have access to

ADAMS or who encounter problems in accessing the documents loca ted in ADAMS

should contact the NRCs PDR reference staff by telephone at 1-800-397-4209 or 301-

415-4737, or by email to PDR.Resource@nrc.gov.

18 IV. Availability of Documents

The documents identified in the following table are available to interested

persons through one or more of the following methods, as indica ted.

DOCUMENT ADAMS ACCESSION NO.

License Amendment Request

Constellation Energy Generation, LLC. ML22154A203 License Amendment to Braidwood Station, Units 1 and 2, Technical Specification 3.7.9, Ultimate Heat Sink, dated June 3, 2022.

v t e Letter Sequence Other
EPID:L-2022-LLA-0082, (Approved, Closed)
Initiation Acceptance... Administration Questions Answers Results Approval Other: ML22157A346, ML22157A356, ML22159A174, ML22159A176, RS-22-075, License Amendment to Braidwood Station, Units 1 and 2, Technical Specification 3.7.9, Ultimate Heat Sink
MONTHYEAR2022-06-30 [Table View]

ML22159A174

Text

SUBJECT:

Dear Mr. Hanson:

Enclosure:

SUMMARY

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