ML20102B704

Forwards Formal Responses to NRC Questions Re 850202 Justification That mid-cycle Insp of Steam Generators Unwarranted.Response Includes Epri/Util Secondary Side Chemistry Program Comparison

ML20102B704
Person / Time
Site:	Fort Calhoun
Issue date:	03/01/1985
From:	Andrews R OMAHA PUBLIC POWER DISTRICT
To:	John Miller Office of Nuclear Reactor Regulation
References
LIC-85-091, LIC-85-91, TAC-60913, NUDOCS 8503040289
Download: ML20102B704 (9)

Text

1 Omaha Public Power District 1623.4 .' ley Omaha. Nebraska 68102 402/ E E 1000 March 1, 1985 LIC-85-091 Mr. James R. Miller, Chief Office of Nuclear Reactor Regulation Division of Licensing U. S. Nuclear Regulatory Commission Washington, DC 20555

References:

(1) Docket No. 50-285 (2) Letter from 0 PPD (R. L. Andrews) to NRC (R. D. Martin) dated February 2, 1985 (LIC-85-040)

Dear Mr. Miller:

Mid-Cycle Inspection of the Fort Calhoun Station Steam Generators The Omaha Public Power District submitted Reference (2) as justification that a mid-cycle inspection of the Fort Calhoun Steam Generators is not warranted.

Discussions between the District and your staff resulted in NRC questions which were answered by the District on an informal basis.

Pursuant to a request from the District's f1RC Project Manat .r that these ques-tions be formally answered, please find attached the District's responses.

Sincerely,/

/,.

lq? k' Tf pV:j R. L. Andrews Division Manager Nuclear Production RLA/CWN/dao I Attachment l

cc: Mr. Robert D. Martin Regional Administrator U. S. Nuclear Regulatory Commission Region IV LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, fl.W. 8503040289 850301 Washington, DC 20036 PDR ADOCK 05000285 G PDR Mr. E. G. Tourigny, flRC Project Managcr Mr. L. A. Yandell, flRC Senior Resident Inspector 00

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I NRC QUESTIONS RELATING TO STEAM GENERATOR MID-CYCLE SHUTDOWN WAIVER Question 1 What is the primary to secondary leakage rate?

Response

Zero Question 2 What is the strain / denting criteria for preventive plugging in the future?

Response

Together with Combustion Engineering, the District responds in the following manner:

The criterion to date for correlating denting with the advisability of plugging is the ability to pass a 0.540" ET probe through the 0.654" ID tube. Any tube showing sufficient denting to obstruct this passage has been plugged. We believe this criterion is consistent with industry standards and is conservative. There-fore, we plan to contini 4 use. We do not believe that current quantitative evaluations of denting are sufficiently precise to be used as final criteria for tube plugging. <

Question 3 How do the new secondary chemistry limits for Fort Calhoun Station compare to EPRI limits?

Response

The EPRI/0 PPD Fort Calhoun Station secondary chemistry limit comparison is presented in the following table.

EPRI/0 PPD SECONDARY SIDE CHEMISTRY PROGRAM COMPARISON Blowdown

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3) pH 8.5 - 9.0 None None 8.5 - 9.2 None None Comment: The District has adopted the CE limits as shown in Action Level 1).

• See Response to Question 4 for OPPD " Secondary System Cctrective Action" from Chemistry Manual . _ Definitions of 1, 2, and 3 are II.A.1, II.A.2, and II. A.3 for all parameters.

• • See EPRI/SG0G PWR Secondary Water Chemistry Guidelines, Revision 1, June 1984 for EPRI Action Level Definitions of 1, 2, and 3.

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• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Cation Con- <0.8 >2 >7 None None None ductivity umho/cm Comment: OPPD is installing on-line analyzers on blowdown for cation con-ductivity. OPPD presently does not have a cation conductivity limit in place but covers the makeup problems and condenser inleakage that cation conductivity covers in the water plant by taking samples of water plant effluent every 25,000 gallons (approximately every 8-10 hours). On-line sodium analyzers cover condenser inleakage and sodiin problems from the water plant continuously. The District will back up the sodium analyzers and cation analyzers with appropriate grab samples. After the on-line analyzers on blowdown for cation conductivity are installed, the District will accumulate data from them and establish a cation conductivity limit and associated action l evel s.

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Sodium ppb <20 > 100 >500 <20, 20-50*** <100 500 Comment: The OPPD limits are the same as, or more conservative than, the EPRI limits. On-line analyzers are installed, and operating on blowdown.

Appropriate grab sanples can be run, and will be run more frequently if all sodium and cation conductivity on-line analyzers are out of service. Action levels for sodium have been adopted to cover increased blowdown, power reduction and immediate shutdown.

• • Action Level and Limit

• Action Level and Limit l Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Chloride ppb <20 100 None <100 <200 None Comment: Until January 1985, the District had only the mercuric nitrate method for determination of chloride and therefore set the chloride limit consistent with the lower limit of detectability (LLD) of that method. Recently, development of the ion specific electrode method (LLD of 10 ppb) has been completed and the District has adopted 20 ppb as a limit for steady state power operations and adopted the 100 ppb action level (effective February 28, 1985).

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• • • Increase blowdown if 20 <[ sodium ppb] <50. If >50, initiate II.A of Response to Question 4..

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• • Action Lev 21 and Limit

• Action Lev 2l and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Sulfate ppb <20 None None <100 <200 None Comment: An ion chromatograph has been purchased by the District and is being pre-operationally tested. Procedures and technique are under development. The District will develop a baseline for normal operation, startup, and shutdown before adopting lower limits and action levels. The District will implement the ion chromatograph procedures and analysis by March 15, 1985.

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Silica ppb <300 None None <300 None None Comment: The OPPD limits are the same as the EPRI limits.

Feedwater

• • Action Level and Limit

• Action tevel and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3) pH 8.8 - 9.2 None None 8.8 - 9.2 None None Comment: The OPPD limits are the same as the EPkl limits.

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3) 0xygen, ppb <5 None None <5 <20 None Comment: The OPPD limits are the same as, or more conservative than, the EPRI limits.

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Iron, ppb <20 None None <20 None None Comment: The OPPD limits as'e the same as the EPRI limits.

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) ~~ 3)

Copper, ppb <2 None None <2 None None Comment: The OPPD limits are the same as the EPRI limits.

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00 Action Level and Limit 0 Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3)

Hydrazine, > 20 None None 10 - 50 50 - 100 None ppb Comment: The District has adopted these limits to allow for adjustment of the hydrazine based on our operational experience, so that oxygen and pH can be controlled seasonally. The District has adopted the Combustion Engineering limit.

Condensate

• • Action Level and Limit

• Action Level and Limit Parameter 1) EPRI 2) 3) 1) OPPD 2) 3) 0xygen, ppb <10 > 30 None <10 <30 None Comment: The OPPD limits are the same as, or more conservative than, the EPRI limits.

Question 4 What are the corrective actions when secondary chemistry limits are exceeded?

Response

AUTHORITY OF OPERATING MANUAL The Operating Manual prescribes the policies, procedures, and instructions to safely operate the Fort Calhoun Station Unit No.1. Adherence to the Operating Manual is mandatory per Fort Calhoun Station Standing Order G-7. The Chemistry Manual is part of the station Operating Manual. The following is extracted from the Operating Manual Procedure CMP-5, Rev.1, currently in effect and governing operations.

I. PRINCIPLES OF CORRECTIVE ACTION Certain steps are mandatory in the resolution of any chemical system abnormality or out-of-specification result. They are:

A. Resample and reanalyze. Correct sampling procedures must be followed as described in OPPD Chemistry Manual, Section CMP-2. Correct analytical procedures must be followed as described in OPPD Chemistry Manual , Section CMP-3.

B. Verification of analytical instrument accuracy. The instrument (s) used must be checked for proper calibration and function. Any chemical reagents used must be verified to be of the proper type, strength, standardization and be known to be free of contamination.

C. Identification of system anomalies. The plant operations and maintenance staffs must be contacted to determine if those groups have taken any action or caused any situation that may have caused the problem being investigated.

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I. PRINCIPLES OF CORRECTIVE ACTION D. Notify the Plant Chemist or Supervisor - C/RP immediately, except as noted below. Immediate notification is considered to b6 within two hours of completion of the analysis. These steps

( A through C) may be deleted or modified only with the approval of the Plant Chemist or Supervisor - C/RP. The resolution of any "out-of-spec" chemical condition or other unusual variation in chemical control may be achieved by, but not be limited to, adjustment to chemical feed rates, use or disuse of deminerali-zer systems, adjustment by plant operation of system flow rates, temperatures, and pressures, maintenance repair of systems, OPPD modification of systems.

II. SECONDARY SYSTEM CORRECTIVE ACTION (Condensate, Feedwater and Steam Gener ator Blowdown)

A. For All Parameters

1. When the nomal range is exceeded, initiate immediate investigalion of the problem, increase the sample frequency to once per eight-hour shift, and increase blowdown to approximately 1% of the main steaming rate as appropriate. The problem must be corrected and the parameter (s) returned to the non:.a1 range within one week.

If this cannot be done, and the paramet.er has a listed abnormal range, power should be reduced to 25% as if the abnomal range had been exceeded.

2. When the abnormal range is exceeded, reduce power to 25%.

Cnntinued plant operation is then possible while correc-tive action is taken. Power ieduction should be initiated within four hours of exceeding the abnomal range. The problem must be corrected and the parameter (s) returned to the nomal range within one hundred (100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />). If this cannot be done, the unit must be shut down as if an ime-diate shutdown limit had been exceeded.

3. When an immediate shutd&;;a limit is exceeded, the unit must be shut down within four hours to prevent rapid

. steam generator corrosion.

B. Additional Corrective Action for pH and Conductivity

1. Verify that at least 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> have elapsed since any pre-vious secondary system chemical feed alteration (or at least one hour if reactor power is being changed). Review reactor power and secondary system chemical feed history for the previous 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

2. Write a chemical instruction to alter, as appropriate, alkameen pump stroke. If alkameen feed is not in service then alter, as appropriate, hydrazine pump stroke. (If this is likely to cause hydrazine to go out of specifica-tion, notify the Plant Chemist.)

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I II. SECONDARY SYSTEM CORRECTIVE ACTION (Continued)

3. If a pump stroke change of more than 5% oppears to be needed during steady state power opera ion, notify the Plant Chemist immediately; otherwise, immediate noti-fication of the Plant Chemist is not required.

4. Resample after the chemical instruction is implemented, nomally within four hours.

C. Additional Corrective Action for Hydrazine

1. Verify that at least 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> have elapsed since any previous secondary system chemical feed alteration (or at least one hour if reactor power is being changed). Review reactor power and secondary system chemical feed history for the previous 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

2. Write a chemical instruction to alter, as appropriate, hydrazine pump stroke.

3. If a pump stroke change of more than 5% appears to be needed during steady state power operation, notify the Plant Chemist immediately; otherwise immediate noti-fication of the Plant Chemist is not required.

4. Resample after the chemical instruction is implemented, nomally within four hours.

D. Additional Corrective Action for Blowdown Rate

1. For steam generator blowdown out-of-specification low but greater than 9000 pounds per hour, notify the Shift Supervi sor.

Question 5 What are the differences between the old and new secondary chemistry program?

Response

A. The administrative, operational, and equipment upgrading implemented in the new program which were not in the old program are:

1. Chemistry holdpoints at startup.

2. Plant procedures require increased investigation and sampling of chemistry parameters that are not in the nomal range.

3. Plant procedures require action including power reduction and shutdown for chemistry parameters that are abnomal as discussed in the Response to Questions 3 and 4 above.

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4. A District commitment to upgrade the on-line analyzers on blowdown, feedwater, condensate, and makeup so that the system upsets can be detected as soon as possible and corrective action can be taken.

The blowdown on-line sodium analyzing system is installed and in service.

5. The plant chemistry staff has improved the analytical capabilities of the lab. The LLD's necessary to meet the new chemistry limits for chloride and sulfate have been established by the pui:hase and implementation of a chloride ion specific electrode and an ion chromatograph, respectively. The District will implement the ton chromatograph by March 15, 1985; the chloride electrode is in service.

Sodium analysis technique improvement has lowered the LLD for sodium to 3 ppb for grab samples.

B. The old secondary limits versus the new limits are as follows:

OLD* NEW PARAMETER 1 2 1 2 3 Blowdown pH 8.2-9.2 7.5-9.5 8.5-9.2 None None cation cond. None None None None None sodium ppb <1000 None <20,20-50** 1100 500 chloride ppb <100 None <100 1200 None sulfate ppb None None <100 1200 None silica ppb <1000 <10,000 <300 None None Feedwater pH 8.8-9.2 8.5-9.2 8.8-9.2 None None oxygen ppb <10 None <5 <20 None iron ppb <25 <50 <20 None None copper ppb <10 125 <2 None None hydrazine ppb 10-50 5-10 10-50 50-100 None Condensate oxygen ppb <5 None <10 <30 None

• For old limits: 1 = Noma 1, 2 = abnomal . No shutdown limits. Power reduction not considered for abnormal.

• • Increase blowdown if 20 <[soditan ppb] <50. If >50, initiate II.A of Response to Question 4.

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..s Question 6 What was your past operational procedure / policy regarding leaks in condenser?

Response

The District's previous policy was to operate in accordance with the Chemistry Manual procedures. These procedures included the limits discussed in I.B.

above and did not provide for action levels related to power reductions and/or shu tdowns. Power reduction and/or shutdown decisions were made by plant manage-ment based on the magnitude of the condenser leak. This previous policy allowed for operation with condenser inleakage while the necessary investigation / search was conducted.

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