ML20071B856

Forwards Part B of Response to NRC 830201 Request for Addl Info Re Util Cycle 8 Reload Application.Part a Response Provided 830218.C-E Retained to Perform Independent Verification of Methodology/Computer Codes

ML20071B856
Person / Time
Site:	Fort Calhoun
Issue date:	02/25/1983
From:	William Jones OMAHA PUBLIC POWER DISTRICT
To:	Clark R Office of Nuclear Reactor Regulation
References
LIC-83-051, LIC-83-51, NUDOCS 8303010228
Download: ML20071B856 (5)

Text

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O Omaha Public Power District 1823 HARNEY e OMAHA, NEBRASKA 68102 m TELEPHONE 536 4000 AREA CODE 402 February 25, 1983 LIC-83-051 Mr. Robert A. Clark, Chief U.

S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of Licensing Operating Reactors Branch No. 3 Washington, D.C.

20555

Reference:

Docket No. 50-285

Dear Mr. Clark:

Cycle 8 Reload Application Your letter dated February 1, 1983 requested additional inform-ation in support of the subject application for the Fort Calhoun Station.

The February 1, 1983 request was divided into two parts, A and B, with a different schedule for each part.

Omaha Public Power District's letter dated February 18, 1983 provided our responses to Part A of your request.

The District's response to Part B of the request is attached herewith.

Sincerely, 1

4M C./ones W.

Divis'on Manager Production Operations l

WCJ/TLP:jmm Attachment cc:

LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, N.W.

Washington, D.C.

20036 Mr.

L.

A.

Yandell, NRC l

j Senior Resident Inspector

()() I

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@303010223 830215 PDR ADOCK 05000285 P

PDR

Attachment OMAHA PUBLIC POWER DISTRICT'S RESPONSE TO ONRR LETTER DATED FEBRUARY 1, 1983 Request 1 Provide a report containing an independent verification by an organization other than OPPD which addresses the District's implementation of the CE methodology / computer codes and which certifies that the results provided for this current reload (Cycle

8) are correct.

District's Response The District retained Combustion Engineering, Inc. (CE) to perform the requested independent verification.

The attached letter (CE-18074-1313) details the results of this effort.

Request 2 Provide your plans and schedules regarding future reloads in which District personnel will be performing any reload safety analyses.

District's Response The District currently has a reload fuel supply contract with Exxon Nuclear Corporation (ENC) for Cycles 9 and 10.

District personnel will be performing reload safety analyses for these reloads.

A decision has not been formally made on the responsibility for reload analyses for future reload cores beyond Cycle 10.-

However, the District will most likely continue to perform reload safety analyses for these reloads.

Cycle 9 is currently scheduled to start operation in May of 1984 and shutdown in September of 1985.

As discussed in the Reference, i

the District's fuel management goal for Cycle 9 is to further reduce the flux to the reactor vessel welds which currently have a large RTNDT shift.

To accomplish this goal, the ENC Cycle 9 reload will contain B C shims.

To account for the B C shims, the 4

4 District will have CE utilize DIT to produce cross sections for the ROCS and PDQ models.

The District may also utilize statistical combination of uncertainties for the Cycle 9 reload.

The District will keep the staff informed on any methodology changes to be utilized in Cycle 9.

The District presently plans to provide the staff with submittals related to new methodologies 180 days prior to startup and Technical Specification changes 90 days prior to startup.

c4 Power Systems Tel 203!6881911 Coneushon Engmeefmg. Inc Telex S0297 1000 Prospect Hoi Road Wmanor. Connecticut 06095 I

POWER February 23. 1983 M SYSTEMS CE-18074-1313 Omaha Public Power District Unit #1 - Fort Calhcun Station General Services Agreement C-E Contract 2381 Mr. W.C.' Jones Omaha Public Power District 1623 Harney Street Omaha, Nebraska 58102

Subject:

REVIEW 0F CYCLE-8 RELOAD APPLICATION

Reference:

OPPD Letter LIC-82-380. Dated November 22, 1982

Dear Mr. Jones:

The purpose of.this letter is to provide you with the results of our review of the referenced letter and supporting documentation.

The referenced letter provided the NRC with OPPD's Cycle-8 reload application for the Fort Calhoun Station, Unit fl.

Subsequent to that application the District requested that Combustion Engineering review the application and supporting documentation prepared by the District to detemine thi adequacy of the results of the work performed by District personnel.

The re, view was accomplished by providing copies of the documents prepared by the District to reviewers in the Physics. Thermal Hydraulics. Safety Analysis l

and Setpoint areas.

The purpose of the review was to determine that the technical specifications, setpoints and conclusions of the safety analysis were conservative.

The review was conducted by the most qualified C-E personnel in each technical area including supervisory and management personnel.

Based on our review it is our judgement thpt the conclusions reached.snd reported by the District, in those areas which referred to C-E codes and methodology, are conservative.

The work described in this letter has r3 quired the expenditure of over 1000 mar. hours and was acceevlished in accordance with the terms and conditions of our Services Agreement.

Please let me know if you have any questions in this regard.

Very truly yours, Sfnk-R.R. Mills Project Marager, Fort Calhcran

. -The startup for Cycle 10 is currently scheduled for November of 1985.

The fuel management and safety analysis requirements have not been established for this core.

Reference:

Letter from W. C. Jones to R. A. Clark, LIC-83-018, dated January 26, 1983.

-Request 3 Your present application contains some analyses that.use the CE-1

. correlation and some analyses that use the W-3 correlation.

Parts of the application are in the form of an updated FSAR.

Provide your plans and schedules for updating your SAR to incorporate the use of only one DNB correlation.

District's Response The District reviewed a number of events which had been previously analyzed for the Cycle 6 application.

The results of this review are discussed in the Reference.

The attached table shows a sum-mary of the Cycle 6 events analyzed to assure that the Specified Acceptable Fuel-Design Limit (SAFDL) on Minimum DNBR (MDNBR) (1.30 using the_W-3 correlation) was met for normal operation and Anticipated Operational Occurrences.

The Cycle 6 analyses also demonstrate acceptable results for the primary pump seizure or seized rotor accident.

A comparison between the transient conditions shown in the table (i.e., heat-flux, pressure and temperature) at which the W-3 correlation reaches its 1.3 limit and those conditions at which the CE-1 correlation reaches its 1.19 limit shows that both limits are approached with similar conditions.

Because of this fact, the District has concluded that a transient whose MDNBR, using the W-3 correlation, does not approach the l.30 limit will not have a MDNBR, using the CE-1 correlation, which approaches the 1.19 limit.

Therefore, the transients which do not approach the 1.30 limit of the W-3 correlation will also not approach the 1.19-limit of the CE-1 correlation.

The results of the Cycle 6 analyses for transient with a SAFDL on MDNBR show that the transients that are within 0.25 DNBR units of i

t the W-3 correlation limit of 1.30 are the CEA withdrawal, seized rotor, and CEA drop.

These transients were analyzed for Cycle 8.

Since the remaining transients are not limiting with respect to MDNBR, they were not analyzed for Cycle 8.

At this time, the District does not plan to reanalyze these transients using the i

i CE-1 correlation.

i

Reference:

Letter from W. C. Jones to R. A.

Clark, LIC-83-047, i

dated February 18, 1983.

1 l

b i

i Sur:rnary of Cycle 6 Analysis t

l

• lamisus Maximus

's i

Maximur.

Core Average Pressurtzer I

Power Level Heat Flus Pressure MONBR

{

Transient (Percent)

(Stu/hr-ftZ)

(osta)

(W-3) i Initial conditions for transients 102 176,213 2053 1.69 Fast control rod withdrawal 112.4 188,721 2270' 1.36 (0.6 x 10-3 ao/sec)

Slow control rod withdrawal 120.1 183,401 2108 1.37 l

(11 x 10-6 ao/sec) i I

j Loss of flow Four-pump constdown 102.3 176.213 2123 1.77 Two-ptmp coastdown 102.3 176.213 2125 1.76 Primary pump seizuer 102 177,000 2440 1.30 Loss of fee &ater flow 102 176.244 2425 1.87 Excessive Load i

Case 1 104.5 180,428 2056 1.53 Case 2 113.5 184,256 2057 1.47 Loss of load Case 1 105 176,244 2530 1.87 l

Case 2 106 176,244 2530 1.87 Rod drop 102 176.213 2053 1.30 1