ML13162A364

Applicant'S Environmental Report Operating License Renewal Stage Braidwood Station, Units 1 and 2. Appendix E

ML13162A364
Person / Time
Site:	Braidwood
Issue date:	05/31/2013
From:	Exelon Generation Co
To:	Office of Nuclear Reactor Regulation
References
Download: ML13162A364 (10)

Text

Appendix E Microbiological Correspondence Braidwood Station Environmental Report

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Braidwood Station Environmental Report Appendix E -

Microbiological Correspondence Byron and Braidwood Stations, Units 1 and 2 Page E-iii License Renewal Application Table of Contents Letter Page Michael P. Gallagher, Exelon Generation, to David W. Culp, Ph.D., Illinois Department of Public Health .............................................................................................................

..... E-1 Ken McCann, MA, LEHP, Illinois Department of Public Health, to Michael P. Gallagher, Exelon Generation .............................................................................................................. E-5 This Page Intentionally Left Blank

on Generation January 23,2013 David W. Culp, Ph.D , Deputy Director Illinois Department of Public Health OBce of Health Protection 525 W. Jefferson St., 2" Floor Springfald, lllinois 62761 -0001

SUBJECT:

Exelon Generation, LLC - Braidwood Station Units 1 and 2 License Renewal Project, Request for information on Therrnophilic Pathogens - Will County

Dear Dr. Culp:

In May 201 3, Exelon Generation Company, LLC (Exebn Generation; a subsidiary of Exelon Corporation) plans to apply to the Nuclear Regulatory Commission (NRC) for renewal of the operating licenses for Braidwood Station (Braidwwd), Units 1 and 2. Both Braidwood Units began commercial operation in 1988. The existing operating license for Braidwood Unit 1 expires October 17, 2026, and the existing operating license for Braidwood Unit 2 expires December 18,2027. License renewal wili extend the license terms to October 17,2046 and December 18,2047, respectively.

The NRC requires that the license renewal application include an environmental report assessing potential impacts from license renewal activities, including continued operations.

One such impact is the "impact of the proposed action [license renewal]

on public health from thermophilic organisms in the affected water" (10 CFR 51,53(~)(3)(ii)(Gf).

Accordingly, we are contacting you to obtain input regarding potential public health concerns associated with the enteric pathogens Salmonella spp and Shigella spp as well as Pseudomonas aenrginosa bacterium, Wrmophific fungi, Legionelja spp in unusually high concentrations, and the free- living amoeba of the genera Naegleffa and Acanthumoeba.

Of greatest concern is the genus Naeglena, comprising four species.

To date only one species, N, fowlen, has been determined to be pathogenic in humans. Project Features Braidwood is located in northeastern Illinois in southwest Will County, approximately 550 miles (mi) southwest of the Chicago metropolitan area, and 20 mi south-southwest of Joliet. The pmperty is approximately 1 mi from the town of Godley, 2 mi from the town of Braidwoad, and 6 mi from the town of Wilmington.

The Kankakee River is approximately 5 mi east of the eastem site boundary.

The foilowing pamgraphs provide background information on the Braidwed cooiing system, and Exeton Generation's assessment of potential effects on the public. We are rfxluesting your help to identify issues regarding thermophilic organisms that we may have overlooked, but that should be addressed in the Braidwmd timnse renewal environmental report. We are partkularly interested in leaming of any infomation your staff believes could exmite the NRC7s review of the Braidwood license renewal appliczation.

Coaling Pond BMdwood Units 1 and 2 have circulating water systems for condenser cooling that withdraw water from an approximately 2,537-acre cooling pond through an intake structure {the lake screen house). Heated cooling water returns to the pond via a discharge canal that is separated from the lake screen house intake by a dike. Dikes are used throughout the cooling pond to slow circulation and increase residence time of cooling water betvveen discharge and intake (and thus lower the water temperature at the intake).

To protect plant components, the 24-hour-average water temperature in an excavated area located within the cooling pond directly in front of the lake screen house is limited by BraidwW Technical Specifications to temperatures not exceeding I00 OF. The Braidwood cooling pond is open to the public for fishing from March 1st until ten days prior to the opening of waterfowl season, which typically occurs in iate October. Cooling pond locations near the lake screen house and cooling water discharge structure are off-limits to boaters, as demarcated with buoys and signs. Swimming in the cooling pond is prohibited.

Braidwood water systems that discharge into the cooling pond are treated with biocides, induding chlorine, to control bio-fouling.

With the exception of these biocides, the water in the cooling pond contains the same chemical constituents as the makeup water pumped into the cooling pond from the Kankakee River to replace water lost to evaporation, seepage, and blowdown, but at higher concentrations because of evaporative water losses from the cooling pond. Kankakee River Blowdown water from the cooling pond is released to the Qnkakee River through an NPDES- permitted (ll.0048321) outfall (Outfall 001) for the purpose of reducing dissolved mineral concentrations in the cooling pond water via a pipeline that discharges through a submerged 7-port diffuser to mid-river.

Blowdm flow rates range between 55.7 cubic feet per second (cfs) and 66.8 cfs, depending on water chemistry (concentrations of mineral solids) in the cooling pond. Based on the results of thermal modeling used to determine the best diffuser configuration, the 7-port diffuser results in a thermal plume consistent with Illinois EPA regulations at Illinois Administmive Code (IAG) Title 35, Section 301.102 (mixing zones) and Secti~n 302.21 1 (water quality standards for temperature).

The maximum surface area of the thermal mixing zone was estimated to be 35 meters wide and to extend 25 meters downstream of the diffuser, for a total area of about 0.22 acre. Under IAC Title 35, Section 302.1 02, "a [temperature] mixing zone must not contain more than 25 percent of the cross-sectional area or volume of flaw of a stream." The Braidwood plume size in relation to the cross sectional area of the river varies seasonally but does not exceed 25 percent sf the river cross sedian. Spciai Condition 3 of NPDES permit lL004.8321 for Braidwood and IAC Tie 35, Section 302.21 1 limit the tempwaturrj increase in the river mused by the station

{beyond the mixing zone) to 5°F abuve natural temperatures.

In addition, allowable maximum mter temperatures at represenbtive ions in the main river are spemed in Special Condition 3 of the NPDES permit. The afbwable maximum water temperature in the Kankakee River (downstream of the blowdown diffuser) is 6S0F during the December-March period and 93OF during the April- Novemkr period.

An Environmental Protection PIan is in rated in the NRC operating licenses for Btaidwod.

The Environmental Pmtection Plan incorpomtes the NPDES permit by reference.

The NPDES permit requires mntinuous mniton'ng of temperature and flow from OuffalI001 (the bldown line) to the Kankakee River. Exelon Generation pmvides monthly monitoring reports to the Illinois EPA. Btaidwaod sends its sanitary wastewter to the town of Braidwood's Sewage Treatment Plant, rather than discharging it to the Kankakee River. This reduces the potential of the Station's discharges to introduce pathogenic organisms into the river. The stream segment (IL-F-16) of the Kankakee receiving the discharge from Braidwood Outfall 001 is identified in the December 2012 //tinois Integmted Wafer Qualm Repod and Section 303(6) List as fully supporting primary (and secandary) contact. These designations am based on fecal cofifom measurements only. Primary contact is "any reaeationaf or other water use in which there is prolonged and intimate contact with the water involving considerable risk of ingesting water in quantities sufficient to pose a significant health hazard such as swimming and water skiing" (IAC Title 35, Section 301,355). NO swimming is allowed in the cooling pond. The discharge area of the cooling pond is off limits to boaters. Discharges to the cooling pond from plant water systems are treated with biocides. For these reasons, Exelon Generation concludes that risk to public health from exposure to therrnophilic organisms that may exist in the Braidwood cooling pond is small. The temperature of the Modown water discharged from the Braidwood cooling pond to the Kankakee River is monitored and reported to the Illinois EPA to vefi compliance with the Station's NPDES permit. The discharge thermal plume (mixing zone) is small, and its size is consistent with Illinois EPA regulatory requirements. Braidwood does not discharge treated sanitary wastewater to the river. For these masons, Exelon Generation concludes that blowdo~nr water discharges from Braidwood are having little effect on the small risk to public health posed by exposure to thermophilic pathogens possibly present in stream segment IL-F-16 of the Kankakee River. Furthermom, because renewal of the Braidwood Units 1 and 2 operating licenses by NRC will authorize no new construction, refurbishment or operational changes to the circulating water system that would affect them1 characteristics of the discharge, Exelon Generation con~iudes that the propmed license renewals would not contribute to any inwease in adverse effects on public health from exposure to A/. ffovven'or any other themophilic pathogen in the Kankakee River. In dosing, we would appreciate remiwing a response from you detailing issues or infamation that we may have overlooked and that your staff believes could expedite NRCs reviw of the Braidwood License Renevval Application.

We would also welcome your confirmation of our condusions that renewing the Braidvvood operating fienses would not inmase adverse effects on pubIic heafth frMn exposure to themphilie patwens in the knkakee River. Because Exelm Gmeragon will incorporate a copy of your response, as well as this letter, into the environmental report that will be submitted to the NRC as part of the Braid License Renewal Application, your response will t helpful if we receive it by February 13,201 3.

Please call Nancy fianek (61 0) 765-5369, Exelon Generation's License Renewal Environmental Lead, if you have questions or require additional information. Thank you in advance for your assistance, Respectfully, Michael P. Gallagher Vice President - License Renewal Exelon Generation Company, LLC

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, '5, lllinub Department of Applies to Both Byron & Braidwood 1X-l) 525-535 West Jefferson Street Sprtngfrerd flltnofs 62761-OOOl . www idph slate ti 3s March 3,2013 Mr. Michael P Gallagher Vice President, License Renewal Exelon Nuclear 200 Exelon Way Kennett Square, PA 19348

Dear Mr. Gallagher:

The Illinois Department of PubIic Health (IDPH) has received your letter requesting that the Office of Health Protection review part of your application for license renewal for Byron Station Units 1 and 2. The Division of Environmental Health has determined that evaluating and commenting on this license renewal application is outside the scope of our mission and that staff do not have the expertise necessary to adequately evaluate the application.

If you have additional health-related questions, please contact Tiffanie Denny, Environmental Toxicologist, at 217-782-5830 or Tm (for hearing impaired use only) 800-547-0466.

Sincerely, Ken McCann, MA, LEHP Chief, Division of Environmental Health

!&#r#~l~g p&BdIg fiaeaIIb9 8ae g@aggl@~ity at B IIBI printed on recycled paper Braidwood Station Environmental Report Appendix E -

Microbiological Correspondence Byron and Braidwood Stations, Units 1 and 2 Page E-6 License Renewal Application

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