BECO-87-015, Requests Emergency Relief from Tech Spec 4.7.B.2.a Re Control Room High Efficiency Air Filtration Sys While 870119 Tech Spec Change Request Being Processed.Relief Required by 870131 to Support off-loading at Facility

Requests Emergency Relief from Tech Spec 4.7.B.2.a Re Control Room High Efficiency Air Filtration Sys While 870119 Tech Spec Change Request Being Processed.Relief Required by 870131 to Support off-loading at Facility

ML20212M443
Person / Time
Site:	Pilgrim
Issue date:	01/27/1987
From:	Howard J BOSTON EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20212M446	List: BECO-87-015, Requests Emergency Relief from Tech Spec 4.7.B.2.a Re Control Room High Efficiency Air Filtration Sys While 870119 Tech Spec Change Request Being Processed.Relief Required by 870131 to Support off-loading at Facility ML20212M554 ML20212M574 ML20212M582
References
BECO-87-015, BECO-87-15, NUDOCS 8701300123
Download: ML20212M443 (5)

Text

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• t BOSTON E'Ois O N COMPANY B00 BOYLSTON STREET GOSTON, MASSACHUSETTS O2199 J. EDWARO HOWARO January 27, 1987 BECo 87-015 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 License DPR-35 Docket 50-293

Subject:

Request for Emergency Relief from Technical Specification 4.7.B.2.a Control Room High Efficiency Air Filtration System

References:

1) BECo Letter #87-007, dated January 19, 1987, " Proposed Technical Specification Change to Section 4.7.B.2.a"

2) NRC Letter to Boston Edison dated January 7, 1975

3) BECo Letter to NRC dated May 1, 1975

Dear Sir:

This letter requests emergency relief from Technical Specification (Tech Spec) 4.7.B.2.a while our Tech Spec change (Reference 1) is being processed.

' Relief is required by January 31, 1987 in order to support fuel off-load at i Pilgrim Station.

Emergency relief is requested because the Tech Spec required surveillance is overly conservative and unachievable even when the system performs as designed. At this time the system is physically operable, can perform its intended safety function and yet is unable to pass the surveillance test as currently specified.

Our research into the origin of this surveillance requirement has led us to conclude that it was incorrectly incorporated into the Tech Spec probably due

{ to an undetected typographical error (see enclosure). Since it's receipt, the surveillance has been met only with great difficulty and by utilizing a 110%

fan flow tolerance on the design flow rate (1000 cfm).

The NRC resident inpsector and plant personnel believed a Tech Spec change requested in August 1985 would address this problem. This Tech Spec change referred to involved the same section of the Tech Spec but did not address

- this issue. Accordingly, we did not recognize the continued existence of this problem until late December 1986.

Recognizing the impending fuel movement date, we pursued all available avenues of compliance to avoid requesting relief. We tested and retested the system, making adjustments and replacing components. We also considered the O

8701300123 870127 QO PDR ADOCK 05000293 1)1 P PDR

BOSTON EDISON COMPANY January 27, 1987 U.S. Nuclear Regulatory Commission Page 2 re-scheduling of fuel movement. However, our attempts proved to be unsuccessful.

One avenue which we are continuing to explore is to perform a temporary modification under 10CFR50.59. This would enable the system to pass the test and would negligibly reduce design margin. While this is allowable, in our judgement, emergency relief is preferred to the temporary modification because ,

it does not unnecessarily change the configuration of the plant to resolve an I administrative error.

Should the Tech Spec problem not be resolved, the impact on the outage is twofold:

1. delay fuel movement which results in additional delays of other outage tasks that cannot begin until fuel is removed from the vessel, and

2. replacement of fuel costs of approximately 300 thousand dollars per day could total in excess of 13 million dollars.

Additional information and justification for this request is enclosed.

No interim compensatory measures are required while the Tech Spec change is being processed because the system is fully operational and meets its design basis. It cannot, however, be qualified against overly restrictive criteria currently in the Tech Spec.

The system exists to protect control room personnel in the event of a radiological event; its presence or absence therefore has negligible impact on the external environment. Emergency breathing apparatus is available as a back-up measure to ensure control room habitability. The change does not create undue risk, and will not endanger life or property because the change will serve to ensure proper system operability.

Reference 1 provided the information necessary to conclude no significant hazards considerations exist and included revised Tech Spec pages.

Mr. Robert Hallisey, Director Radiation Control Program, Mass. Dept. of Public Health was contacted on January 26, 1987 and apprised of the contents of this letter, the January 19, 1987 letter, and the circumstances involved in this issue.

Very truly yours, TAV/ns f%J Enclosure l cc: see next page i

BOSTON, EDISON COMPANY January 27, 1987 U.S. Nuclear Regulatory Commission Page 3 cc: Mr. John A. Zwolinski, Director BWR Project Directorate #1 Division of Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555 Dr. Thomas E. Murley Regional Administrator Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406

Enclosure to BECo Letter 87-015 dated, January 27, 1987 DISCUSSION:

The intent of the existing Tech Spec surveillance 4.7.B.2.a is to ensure that filter cartridges in the control room high efficiency air filtration system are clean and unrestricted. To ensure this a differential pressure measurement is taken at design flow rate and compared to the surveillance test limit. The existing limit is too restrictive in that the acceptance criterion of 3" of water at 1000 cfm can only be achieved with the application of the i 101 fan flow tolerance found in Tech Spec 3.7.B.2.d. This has been our procedural practice since the incorporation of 4.7.B.2.a into Pilgrim's Tech Specs. The history of how these acceptance criteria came about lends credence to the fact that this is not a technical issue but merely administrative.

In a letter dated January 7,1975, ( Attachment 2) the NRC requested BECo to augment the Limiting Conditions for Operation (LCO) and Surveillance Requirements related to installed filter systems. These additional LC0's and Surveillances were considered necessary in order to ensure high confidence that the systems will function reliably, when needed, at a degree of efficiency equal to or better than that assumed in the accident analyses.

Accompanying this letter was a set of model Tech Specs for guidance in what the NRC would consider acceptable. For Control Room Air Treatment Systems, the model Tech Specs recommended an acceptance criteria of less than 6" of water at system design flow rate. BECo responded by proposing an acceptance criteria of less than 9.5" of water at 1000 cfm (Attachment 3).

Our notes from a series of telephone conversations between BECo and NRC management indicate that less than 8" of water at 1000 cfm was an acceptable change to our initial proposal of less than 9.5" of water. When the amendment was issued (Amendment 42 dated May 12, 1980) the wording specified less than 3" of water at 1000 cfm. No material can be found on our docket concerning the origin of the 3". This probably was a typographical error. Amendment 42 was necessary for startup from Refuel Outage #4. The surveillance was conducted and passed with the procedural acceptance criteria of 1 10% fan flow. This acceptance criteria of Tech Spec 3.7.B.2.d was assumed to be inherent to the 1000 cfm of Tech Spec 4.7.B.2.a. Plant startup occurred on May 21, 1980.

BECo continued to utilize this assumption, but meeting this specification has been difficult and marginal.

Absent the NRC granting this emergency relief fuel movement could be delayed.

This would effectively derate Pilgrim for whatever period of time it takes to process the change in the normal fashion (i.e., DL Operating Procedure 228).

Delaying fuel movement would result in additional delays of other outage tasks that cannot begin until fuel is removed from the vessel. The external expertise needed to perform these tasks has been pre-arranged and is available for a specified period of time only. Re-scheduling this work would depend

O upon their flexibility in changing commitments already made elsewhere in the Industry. Examples of the tasks which would be jeopardized are:

- Relocation of the Reactor Water Level reference legs outside the drywell to eliminate heatup induced level errors

- Analog Trip System Installation to improve reliability and eliminate RPS System challenges

- Reactor Vessel Dry Tube Inspection / Replacement (SIL 409)

- In-Vessel Instrument Line Inspection (SIL 420)

- Installation of Hydrogen Water Chemistry Probe.

i Fuel unloading is scheduled to commence on January 31, 1987 and will take

, between 10 and 30 days to complete. Recognizing this date could shift slightly due to unforeseen circumstances, we will keep the NRR Project Manager

apprised on a daily basis.

Attachments: 1) BECo Letter #87-007, dated January 19, 1987, " Proposed Technical Specification Change to Section 4.7.B.2.a"

2) NRC Letter to Boston Edison dated January 7, 1975 1 3) BECo Letter to NRC dated May 1, 1975 i

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10CFR50.90 BOSTON EoisDN COMPANY B00 BovLsTON STREET BOSTON. MASSACHUSETTS 02199 J. EDWARD HOWARD vess pia. sos v January 19, 1987 BECo 87-007 Propo:ed Change 87-01 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 License DPR-35 Docket 50-293 Proposed Technical Specification Change to Section 4.7.B.2.a

Dear Sir,

Pursuant to 10CFR50.90, Boston Edison hereby proposes the attached modification to Appendix A of Operating License No. DPR-35. This modification revises the acceptance criteria for flow and filter train differential pressure for the Control Room High Efficiency Air Filter System (CRHEAF). The proposal is made to reduce overly restrictive criteria, the strict interpretation of which prevents the system from being considered operable.

The strict interpretation is also in conflict with vendor design information.

Should you wish further information on this submittal, please contact us.

Very truly yours,

! PMK/ns Attachment 0

One Original and 37 Copies Commonwealth of Massachusetts)

County of Suffolk )

! Then personally appeared before me, J. E. Howard, who, being duly sworn, did

! state that he is Vice President - Nuclear Engineering and Quality Assurance Department of Boston Edison Company and that he is duly authorized to execute and file the submittal contained herein in the name and on behalf of Boston Edison Company and that the statements in said submittal are true to the best of his knowledge and belief.

My commission expires: /3ddy. dL /988 _

'(

L DATE V NOTARY UBLIC

$ a 4 ee next page . ~

BOSTON EDISCN COMPANY Ja-nuary 19, 1987 ,

J.S. Nuclear Regulatory Commission Page 2 cc: U.S. Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 Senior P.RC Resident Inspector Pilgrim Nuclear Power Station Robert M. Hallisey, Director Radiation Control Program Mass. Dept. of Public Health .

150 Tremont Street F-7 Boston, MA 02111 1

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Proposed Change to Technical 50ecifications Proposed Change Reference is made to Pilgrim Station Operating License No. DPR-35, page 1588 Sec tion 4.7.8.2.a. This currently states:

At least once every 18 months the pressure drops across each combined filter train shall be demonstrated to be less than 3 inches of water at 1000 cfm.

This will be changed to provide 6 inches of water pressure drop and a 107.

tolerance to the flow rate, and shall state, in part: "

... less than 6 inches of water at 1000 cfm or the calculated equivalent."

Reason for Change .

The change is proposed to allow flexibility in surveilling the Control Room High Efficiency Air Filtration (CRHEAF) system. The existing 1000 cfm is too restrictive in that no tolerance is specified, therefore strict compliance requires a flow rate of exactly 1000 cfm. This is contrary to common operating practice in that it does not provide for small variations in the system, the atmosphere, or measuring at any particular surveillance. .

The "3 inches of water" pressure drop is very restrictive when applied to the combined filter train, as currently required. A review of vendor design information indicates that 3 inches of differential pressure is the vendor recommended action point for changeout for each HEPA filter. Each filter train consists of a prefilter, two HEPA filters, a charcoal adsorber, and heaters, all of which contribute to differential pressure. When 3 inches is applied to the combined HEPA filters it is overly restrictive vis-a-vis the vendor recommended criteria, i.e., filters should be either tested separately to 3 inches or less, or the differential pressure raised to 6 inches or less for the combined filter train.

Safety Considerations The addition of a " calculated equivalent" to the CRHEAF acceptance criteria is in keeping with the standard engineering and operating practice of providing tolerance in measuring HVAC system flow performance, and allows the procedural

.! use of a performance curve with flow rates bounded by TS 3.7.B.2.d.

The changing of the differential pressure criterion to 6 inches of water is i acceptable for the following reasons:

o The summation of vendor recommended action levels for all components in each filter train gives a total differential pressure of approximately 8 inches of water; o The maximum vendor allowed differential pressure across any one HEPA

. unit is 8 inches of water; o The expected value for the summation of component differential pressures for a filter train with new filter media is approximately 3.75 inches of water; l

Therefore, a value of 6 inches of water across the combined filter train components is conservative because it will prompt action before any single HEPA would reach its maximum. and before the vendor recommended level for the combined filter train is reached.

This proposed change has been reviewed by and approved by the Operations Review Committee and reviewed by the Nuclear Safety Review and Audit Committee.

Supporting Information and No Significant Hazards Conditions Analyses The proposed change provides a tolerance to the test success criteria for CRHEAF by allowing the use of a procedural curve relating differential pressure to 1000 cfm as bounded by TS 3.7.B.2.d. The change also raises the differential pressure criteria to 6 inches from 3 inches of water.

The Code of Federal Regulations,10CFR50.91 requires that at the time a licensee requests an amendment, it must provide to the Commission its analysis 4 using the standards in 10CFR50.92, about the issue of no significant hazards consideration. Therefore, in accordance with 10CFR50.91 and 10CFR50.92 the following analysis has been performed.

1. Operating Pilgrim Station in accordance with the proposed amendment will not involve a significant increase in the probability or consequences of an accident previously evaluated.

The CRHEAF creates a positive pressure in the Control Room, using air from which it has filtered out radiciodine and particulates. Currently, TS 4.7.B.2.a requires that at least once every 18 months a pressure drop of less than 3 inches of water be demonstrated across the filters at a flow rate of 1000 cfm. TS 3.7.B.2.d requires that CRHEAF fans operate within 1000 cfm 1107.. The system is designed to provide a positive Control Room pressure if the fans can provide a flow rate of 900 to 1100 cfm and the filters are not plugged. Vendor information indicates that filter

degradation from plugging is indicated by a differential pressure of 3 inches or greater of water across each HEPA filter. Therefore, when j measured across two HEPA filter elements, and the rest of the CRHEAF a

components which create differential pressure, a differential of less than 6 inches of water demonstrates that HEPA plugging has not reached action levels. Hence, if the fans can generate 900 to 1100 cfm to satisfy 3.7.B.2.d, and has a pressure drop across the filter trains less than 6 inches at 1000 cfm or the calculated equivalent, sufficient flow exists to provide a positive pressure in the Control Room. Therefore, the purpose of the CRHEAF as a mitigator of the results of an accident will not be i

impaired by this proposed change. Hence, allowing the differential pressure of 6 inches of water 1000 cfm to be established at flow rates between 900 and 1100 cfm in conformance with a calculated procedural acceptance curve will not involve a significant increase in the probability or consequences of an accident previous!'y analyzed.

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2. Operating Pilgrim Station in accordance with the proposed amendment will not create the possibility of a new or different kind of accident from any i

accident previously evaluated.

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The purpose of CRHEAF is to mitigate the consequences of certain accidents by filtering out radiciodines and particulates from air which is then used to maintain a positive pressure in the Control Room. The amendment allcws a tolerance by allowing a calculated value, based on 6 inches of water at 1000 cfm to be used for demonstrating that the filter train elements are not plugged. The flow range for the calculated value is 900 - 1100 cfm, determined by existing TS 3.7.8.2.d.

The change to 6 inches of water from 3 is in compliance with vendor information. The change of these criteria therefore is consistent with the design and fan capabilities of the system, and does not degrade the system's ability to perform its designed function of providing positive pressure in the Control Room with filtered air; therefore, operating Pilgrim in accordance with the proposed change will not create the possibility of a new or different kind of accident from any accident ,

previously evaluated.

3. Operating Pilgrim Station in accordance with the proposed amendment will not involve a significant reduction in the margin of safety.

The proposed change does not reduce the CRHEAF's ability to perform its designed function of creating a positive pressure in the Control Room with filtered air. Hence, accident analysis which take credit for CRHEAF as a mitigator are not affected and the safety margin remains the same.

Therefore, the operation of Pilgrim in accordance with the proposed amendment to TS 4.7.B.2.a will not involve a significant reduction in the margin of safety.

Schedule of Change This change will become effective immediately following approval by the Commission.

Fee Determination Pursuant to 10CFR170.12(c) an application fee of $150.00 is appropriate. The fee will be provided under a separate cover letter in the near future.

. 3.7.B (Continued) 4.7.B (Continued)

2. Control Room High E'ficiency Air 2. Control Room High Efficiency Air Filtration System Filtration System

• a. Except as specified it a. At least once every 18 months Specification 3.7.B.2. Delow, the pressure drop across each both trains of the Control Room combined filter train shall be High Efficiency Air Filtration demonstrated to be less than 6 System used for the processing inches of water at 1000 cfm or of inlet air to the control room the calculated equivalent.

under accident conditions and the diesel generator (s) required b. (1.) The tests and analysis for operation of each train of of Specification the system shall be operable 3.7.B.2.b shall be whenever secondary containment performed once every 18 integrity is required and during months or following fuel handling operations. painting, fire or chemical release in any ,

b. (1.) The results of the inplace ventilation zone cold DOP tests on HEPA communicating with the filters shall show 199% system while the system DOP removal. The results is operating.

of the halogenated hydrocarbon tests on (2.) Inplace cold DOP testing charcoal adsorber banks shall be performed after shall show 199% each complete or partial halogenated hydrocarbon replacement of the HEPA removal when test results filter bank or after any are extrapolated to the structural maintenance initiation of the test. on the system housing which could affect the (2.) The results of the HEPA filter bank bypass laboratory carbon sample leakage.

analysis shall show 195%

methyl lodide removal at a (3.) Halogenated hydrocarbon velocity within 10% of testing shall be system design, 0.05 to performed after each 0.15 mg/m' inlet methyl complete or partial lodide concentration, 170% replacement of the R.H., and 1125'F. charcoal adsorber bank or after any structural

• c. From and after the date that one maintenance on the train of the Control Room High system housing which Efficiency Air Filtration System could affect the is made or found to be incapable charcoal adsorber bank of supplying filtered air to the bypass leakage.

control room for any reason, reactor operation or refueling (4.) Each train shall be operations are permissible only operated with the during the succeeding 7 days. heaters in automatic for If the system is not made fully at least 15 minutes operable within 7 days, reactor every month.

• Conditional Relief granted from this (5.) The test and analysis of LCO for the period February 5, 1982 Specification to startup for cycle 6. 3.7.8.2.b.(2) shall be performed after every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of system operation.

Amendment No. 158B hb {d -