NLS2002125, Clarification of Amendment No.194 Safety Evaluation Cooper Nuclear Station

Clarification of Amendment No.194 Safety Evaluation Cooper Nuclear Station

ML022840400
Person / Time
Site:	Cooper
Issue date:	10/07/2002
From:	Denise Wilson Nebraska Public Power District (NPPD)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NLS2002125
Download: ML022840400 (5)

Text

H Nebraska Public Power District Nebraska's Energy Leader NLS2002125 October 7, 2002 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001

Subject:

Clarification of Amendment No. 194 Safety Evaluation Cooper Nuclear Station, NRC Docket No. 50-298, DPR-46

References:

1. Nebraska Public Power District (NPPD) letter NLS2002015 to U. S.

Nuclear Regulatory Commission (NRC) dated January 21, 2002

2. U. S. NRC letter to NPPD dated September 18, 2002 The purpose of this letter is for NPPD to clarify statements made in the safety evaluation (SE) accompanying Amendment No. 194 to the Cooper Nuclear Station (CNS) Operating License No. DPR-46. Amendment No. 194, forwarded by Reference 2, revised Technical Specifications Surveillance Requirement 3.7.3.1 to eliminate unnecessary restrictions regarding how the Reactor Equipment Cooling System surge tank level is monitored. The amendment was issued in response to NPPD request for proposed change submitted by Reference 1. NPPD reviewed the SE and identified two areas requiring clarification. The clarification is discussed in the attachment to this letter. NPPD considers the SE to remain valid with the clarification and does not require a reply.

If you have any questions concerning this matter, please contact Paul V. Fleming at (402) 825-2774.

Sincerely, David L. Wilson Vice President-Nuclear

/rer N

Attachment:

Cooper Nuclear Station P 0 Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 http //www nppd corn

NLS2002125 Page 2 of 2 cc: Regional Administrator w/ attachments USNRC - Region IV Senior Project Manager w/ attachments USNRC - NRR Project Directorate IV-1 Senior Resident Inspector w/ attachments USNRC Nebraska Health and Human Services w/ attachments Department of Regulation and Licensure NPG Distribution w/o attachments Records w/ attachments

NLS2002125 Attachment Page 1 of 2 Attachment Clarification of Amendment No. 194 Safety Evaluation Cooper Nuclear Station (CNS), NRC Docket 50-298, License DPR-46

References:

1. Nebraska Public Power District (NPPD) letter NLS2002015 to U. S.

Nuclear Regulatory Commission (NRC) dated January 21, 2002, "Proposed License Amendment Related to Reactor Equipment Cooling (REC) Surge Tank Level Surveillance Requirement (SR) 3.7.3.1"

2. U. S. NRC letter to NPPD dated September 18, 2002, "Issuance of Amendment Re: Reactor Equipment Cooling Surge Tank Level Surveillance Requirement (TAC No. MB4050)"

The following is clarification of two issues discussed in the safety evaluation (SE) accompanying Amendment No. 194 (Reference 2).

1. SE Section 3.0, third paragraph. This paragraph discusses use of the gauge glass for monitoring level in the REC System surge tank. The SE states:

"The licensee developed an alternate practical method to monitor the REC surge tank level to 'verify REC surge tank level is within limits' without reliance on the gauge glass."

The last paragraph in Section 3.0 of the NPPD amendment request (Reference 1) states:

"From a reliability and practicality perspective, alternate means for appropriate monitoring of the REC surge tank level can be established without reliance on the gauge glass."

The first paragraph in Section 6.0 of the amendment request states:

"While this method is an acceptable means of determining surge tank level, alternate methods could be established to determine surge tank level."

Prior to the change issued by Amendment No. 194, CNS Technical Specification Surveillance Requirement SR 3.7.3.1 required use of the gauge glass for monitoring level in the REC surge tank. The purpose of the amendment was to allow the use of alternate methods. As such, alternate methods will be developed if needed, e.g. in the event that the gauge glass breaks.

NLS2002125 Attachment Page 2 of 2

2. SE Section 3.0, fourth paragraph. This paragraph discusses the acceptance criteria in plant procedures used to monitor surge tank level. The discussion refers to two acceptance criteria as follows:

"(1) an absolute minimum level requirement of greater than or equal to 5.25 inches from the bottom of the sight glass in the surge tank; and (2) a maximum rate of level change of 5.625 inches in a 24-hour period."

The second paragraph of Section 4.0 of the amendment request (Reference 1) discusses the two acceptance criteria imposed by procedure for monitoring surge tank level. The two acceptance criteria were described as follows:

"(1) an absolute minimum level requirement (>5.25" as referenced from the bottom of the sight glass) in the surge tank is required to be maintained; and (2) a requirement to monitor rate-of-level change is imposed, which provides added conservatism to the minimum level requirements when monitored rates of change in surge tank level are greater than 5-5/8" in a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period."

The rate-of-level change of 5-5/8 (5.625) inches in a 24-hour period, mentioned in both the amendment request and the SE, is the maximum allowed with the REC surge tank level at the low level alarm point and no compensatory actions being taken. Criterion 2, as stated in the amendment request, was intended to reflect that the procedure requires the rate of leakage from the tank to be monitored, and that leak rates greater than 5-5/8 inches in a 24-hour period are allowed provided that additional inventory in the tank is maintained (i.e., "added conservatism to the minimum level requirements"). The established minimum levels for leak rates greater than 5.625 inches in a 24-hour period are based on ensuring a seven-day inventory in the surge tank is maintained.

With this clarification, the procedure acceptance criterion regarding the maximum rate-of level change as stated in the SE, is understood to refer to the maximum allowable rate-of level change when the tank inventory is at the low level alarm point.

ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS Correspondence Number: NLS2002125 I The following table identifies those actions committed to by Nebraska Public Power I District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory commitments. Please notify the NL&S Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.

COMMITTED DATE COMMITMENT OR OUTAGE None v

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