ML20139A303

Forwards RAI Re Proposed TS Changes to Reactor Coolant Sys Flow Limit Concerning Radiological Controls for Plant

ML20139A303
Person / Time
Site:	Calvert Cliffs
Issue date:	04/22/1997
From:	Dromerick A NRC (Affiliation Not Assigned)
To:	Cruse C BALTIMORE GAS & ELECTRIC CO.
References
TAC-M97855, TAC-M97856, NUDOCS 9704250191
Download: ML20139A303 (6)

Text

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, Mr. Charles H. Cruse April 22, 1997 Vice President - Nuclear Energy

, Baltimore Gas and Electric Company Calvert Cliffs Nuclear Power Company 1650 Calvert Cliffs Parkway Lusby, Maryland 20657

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION - PROPOSED TECHNICAL SPECIFICATION CHANGES TO REACTOR COOLANT SYSTEM FLOW LIMIT REGARDING RADIOLOGICAL CONTROLS CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NOS.

1 AND 2 (TAC NOS. M97855 AND M97856)  :

Dear Mr. Cruse:

The NRC staff has reviewed your response of March 25, 1997, to our Request for s Additional Information dated March 5,1997, regarding changes to the reactor

, coolant system flow limit amendment related to radiological controls. Based ,

4 on our review, we have concluded that the information provided is insufficient for the staff to perform an assessment of the acceptabil'.ty of the proposal to plug additional tubes in the steam generators. The staff believes the i

responses have been inadequate and these inadequacies can extend the time necessary for receiving staff approval of the amendment. It is requested that  ;

Baltimore Gas and Electric Company provide sufficient information so that we i may perform accident dose assessments to support your amendment. The l information required is addressed in the enclosure.  ;

In order to meet your schedule, the staff requests that additional information be provided within 30 days of receipt of this letter.

If you have any questions regarding this matter, please contact me at 301-415-3473.

Sincerely, IS/

Alexander W. Dromerick, Senior Project Manager Project Directorate I-1 Division of Reactor Projects - I/II l Docket Nos. 50-317

> and 50-318 c

Enclosure:

Request for Additional j Information cc w/ encl: See next page NE E @M DISTRIBUTION:

ADromerick LDoerflein,RI Docket File PUBLIC SVarga SBajwa. 0GC mt' P

y'I PDI-1 Reading Slittle ACRS DOCUMENT NAME:G:\CCl-2\CCM97855.RAI To receive a copy of this document, indicate in the box: "C" - Copy without attachment / enclosure "E" - Copy with attachment / enclosure "N" - No copy 0FFICE PJppy-/

i l h// lE LA:PDI M l D:PDI 1 ,,/1 l l l NAME M @ i W:mw Slitt V SBajwa /f % _,

DATE 04,5,t//97 04/5L/97 04/ @ /97' 04/ /97 04/ /97 9704250191 970422 e ""icial Record Copy PDR ADOCK 05000317 P PDR

1. 1. %q g g 1 UNITED STATES j

y g NUCLEAR REGULATORY COMMISGlON o

• WASHINGTON, D.C. 20665-0001

%, . . . . . p' April 22, 1997 Mr. Charles H. Cruse Vice President - Nuclear Energy Baltimore Gas and Electric Company Calvert Cliffs Nuclear Power Company 1650 Calvert Cliffs Parkway Lusby, Maryland 20657

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION - PROPOSED TECHNICAL .

SPECIFICATION CHANGES TO REACTOR COOLANT SYSTEM FLOW LIMIT REGARDING '

l RADIOLOGICAL CONTROLS CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NOS.

1 AND 2 (TAC NOS. M97855 AND M97856) l

Dear Mr. Cruse:

The NRC staff has reviewed your response of March 25, 1997, to our Request for Additional Information dated March 5,1997, regarding changes to the reactor '

coolant system flow limit amendment related to radiological controls. Based on our review, we have concluded that the information provided is insufficient for the staff to perform an assessment of the acceptability of the proposal to plug additional tubes in the steam generators. The staff believes the '

responses have been inadequate and these inadequacies can extend the time necessary for receiving staff approval of the amendment. It is requested that Baltimore Gas and Electric Company provide sufficient information so that we '

may perform accident dose assessments to support your amendment. The information required is addressed in the enclosure.

In order to meet your schedule, the staff requests that additional information be provided within 30 days of receipt of this letter.

If you have any questions regarding this matter, please contact me at 301-415-3473.

Sincerely, exand r W. Dromerick, Senior Project Manager Project Directorate I-1 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket Nos. 50-317 and 50-318

Enclosure:

Request for Additional Information cc w/ encl: See next page

l

. l 1

Mr. Charles H. Cruse Calvert Cliffs Nuclear Power Plant Baltimore Gas & Electric Company Unit Nos. I and 2 l

cc: l 1

i l

President Mr. Joseph H. Walter, Chief Engineer )

Calvert County Board of Public Service Commission of <

Commissioners Maryland 175 Main Street Engineering Division Prince Frederick, MD 20678 6 St. Paul Centre  ;

Baltimore, MD 21202-6806 l James P. Bennett, Esquire l Counsel Kristen A. Burger, Esquire '

Baltimore Gas and Electric Company Maryland People's Counsel P.O. Box 1475 6 St. Paul Centre Baltimore, MD 21203 Suite 2102 Baltimore, MD 21202-1631 Jay E. Silberg, Esquire Shaw, Pittman, Potts, and Trowbridge Patricia T. Birnie, Esquire 2300 N Street, NW Co-Director Washington, DC 20037 Maryland Safe Energy Coalition P.O. Box 33111 Mr. Terrence J. Camilleri, Director, Baltimore, MD 21218 NRM Calvert Cliffs Nuclear Power Plant Mr. Loren F. Donatell 1650 Calvert Cliffs Parkway NRC Technical Training Center Lusby, MD 20657-4702 5700 Brainerd Road Chattanooga, TN 37411-4017 Resident Inspector U.S. Nuclear Regulatory ,

Commission '

P.O. Box 287 St. Leonard, MD 20685 Mr. Richard I. McLean Administrator - Radioecology Department of Natural Resources 580 Taylor Avenue Tawes State Office Building, B3 Annapolis, MD 21401 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406

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d I Reauest for Additional Information  !

Proposed Amendment for Reduced Flow l Calvert Cliffs Nuclear Power Plant. Unit Nos. I and &

l. The consequences-of the following accidents must be assessed to support the increase in SG tube plugging from 800 to 2,500 tubes per SG.

a. Steam Generator tube rupture (SGTR)

b. Main Steam Line Break (MSLB) l 3 c. Loss of Coolant Accident (LOCA)

d. Rod Ejection

e. Seized rotor

2. Baltimore Gas and Electric Company (BGE) must address whether the proposed additional plugging introduces the possibility of a new or different accident .than previously assessed or results in a reduction in l the margin of safety. Specifically, the condition which is of concern  ;

to the staff is that of overfill of the SG which may be experienced in '

the tube rupture.

J  !

BGE has performed accident analyses of the MSLB and the seized rotor.  ;

In a response to a question from the staff, the licensee indicated that i they had performed a qualitative assessment of the impact of tube plugging on the rod ejection and the SGTR accidents. Based upon this assessment, the. licensee indicated that "the appropriate NRC acceptance criteria for each event were met. Therefore, the analyses of record (including dose assessment) for these events were not revised."

It appears inappropriate for BGE to conclude that, because they determine that the doses are within the staff's acceptance criteria, a revised dose analysis need not be submitted for the staff's review and approval. By that assumption, is the licensee inferring that the analyses for which they are submitting revised assessments exceed the staff's dose criteria? If the licensee concluded that the consequences of the SGTR and the rod ejection were greater than that previously assumed then they would have an unreviewed safety question and the licensee would be required to have those analyses reviewed and approved by the staff.

The requirement for additional analyses is necessary because the additional plugging would result in an increase in the quantity of primary coolant released to the faulted SG in the event of an SGTR.

This increase would result in additional releases from the faulted SG.

In addition, because more tubes are plugged, the heat removal capability of each SG is diminished. Consequently, it will take longer for faulted SG to be isolated and for the intact SG to remove the decay heat from the core. For the intact SG, since heat removal capability is decreased, the time to remove decay heat is increased from previous evaluations. Consequently, steam releases from both SGs are likely to be increased from previous evaluations.

Enclosure

e

, )

l For the rod ejection accident, BGE must address whether the additional 1 SG tube plugging results in a greater quantity of fuel melting or in a l

. greater quantity of fuel rods which experienced gap releases? If it  ;

does, then the consequences would be increased above those previously 1 analyzed. Anunreviewed safety question would exist. The licensee would have to assess the offsite and onsite consequences and the staff would need to perform a confirmatory analysis and issue an SE indicating that the consequences of a rod ejection accident remain acceptable with the additional SG tube plugging.

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