ML20247F029

Redistributed Forwarding Amend 112 to License DPR-54.Amend Revises Tech Specs Re Increasing Max Closure Time for Selected Containment Isolation Valves & Addition of 12 Valves to Table 3.6-1

ML20247F029
Person / Time
Site:	Rancho Seco
Issue date:	07/20/1989
From:	Reynolds S Office of Nuclear Reactor Regulation
To:	Firlit J SACRAMENTO MUNICIPAL UTILITY DISTRICT
References
TAC-60960, NUDOCS 8907270070
Download: ML20247F029 (3)

Text

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.RE-DISTRIBUTED JULY 20, 1989 July 17, 1989.

3 Docket No. ' 50-312 '

. f r Mr. Joe Firlit Chief Executive Officer, Nuclear l Rancho Seco huclear Generatir.g Station.- J 14440 Twin Cities Road I Herald, California 95638-9799 I

SUBJECT:

AMENDMENT NO. 112 TO FACILITY OPERATING LICENSE NO. DPR-54 RANCHO SECO NUCLEAR GENERATING STATION (TAC NO. 6096C)

The Commission has issued the enclosed Amendment No.112 t o Facility Operating License No. DPR-54 for the Rancho Seco Nuclear Generating Station. This amendment consists of changes to the Technical Specifications (TS) in response to your application dated February 28, 1986, as revised May 14, 1987, and' Augu:;t 31. 1920.

This amendment reviseo the Technical Specifi ,ations pertaining to increasing the maximum closure time for selected containment isolation valves and the addition of.12 valves to Table 3.6-1.

A copy of.our Safety Evaluation is also enclosed. Notice of Issuance will be l included in the Comission's bi-weekly Federal Reoister notice.

Sincerely,

/s/

Stevc:. A. Reynolds, Project Manager Project Directorate V l Division of Reactor Projects III, IV, Y and Special Project.c

Enclosures:

1. Amendment No. 112to DPR-S4

2. Safety Evaluation cc w/ enclosures:

See next page DISTRIBUTION _ _ .

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' Docket No. 50-312

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3 ,l Mr. Joe.Firlit Chief Executive Officer, Nuclear.

Rancho Seco Nuclear Generatir.g Station .

14440 Twin Cities Road Herald, California 95538-9799

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SUBJECT:

AMENDMENT NO. 112 TO FACILI1Y. OPERATING LICENSE NO. DPR-54 l RANCHO SEC0 NUCLEAM GENERA 11NG STATION (TC NO. 60960) i l

The Commission has issued the encicsed Amendment No.112 to Facility Operoting License No. DPR-54 for the Rancho Seco Nuclear Generating St6 tion. This amendment consists of changes to the Technics 1 Specifications (TS) in response l to your 6pplication deted Febtvary 28, 1986, as~ revised May 14, 1987, and 1 August 31, 1988. ,

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This amendment revised the Technical Specifications pertaining to increasing the maximum closure time for seltected cor,tainment isolation valves and the addition of 12 valves to Table 3.6-1.

A ctpy of our~ Safety Evaluation is also enc 1csed. Notice of Issuance will be 4 l included in the Commission's bi-weekly Federal Register notice.

Sincerely, ,

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% dl (A I Steven A. Reynolds, Project Manager Project Directorate V i Division of Reactor Projects !!I, i IV, V and Special Projects )

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Enclosures:

'1. Amendment No.112 to OPR-54  !

2. Safety Evaluation I

ec w/ enclosures-See next page i

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. . Mr. ' Joe Firlit ' Rancho Seco Nuclear Generating Station

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cc:

Mr. David S. Kaplan Secretary ' Mr. John Bartus andGeneralCounsel Ms. JoAnne Scott

Sacramento Municipal Utility District Federal Energy Regulatory Commission 6201 S Street 825 North Capitol Street, N. E.

P.O. Box 15830 k'ashington, D.C. 20425 Sacramento, California 95813-Thomas A. Baxter, Esq. Ms. Helen Hubbard Shaw, Pittman, Potts & Trowbridge P. O. Box C3 2300 N Street, N.W. Sunol, California 94586 Washington, D.C. 20037.

Mr. Steven Crunk' Manager, Nu: lear Licensing Sacramento Municipal Utility District

- Rancho Sect Nuclear Generating Station 14440 Twin Cities Road .

Herala, California 95638-9799

'Mr. Rotert B. Borsum, Licensing Representative Babcock & Wilcox Nuclear Power Division 1700 Rockville Pike - Suite 525 Rockville, Maryland 20852 Resident Inspector / Rancho Seco c/o D. S. N. R. C. i 14440 Twin Cities Road Herald, California 95638-Regional Adrninistrator, Region V U.S. Nuclear Regulatory Commission 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Mr. Paul Szalinski, Chief Radiological. Health Branch State Department of Health Services 714 P Street, Office Building #8 Sacramento, California 95814 Sacramento County Board of. Supervisors 700 H Street, Suite 2450 Sacramento, California 95814 i

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• • ..e S ACRAMENTO . NUN I C I PAL . UT I L I TY . D I STR I CT DOCKET N0. 50 312 RANCHO SECO NUCLEAR GENERATING. STATION ANENDMENT.TO. FACILITY OPERATING. LICENSE I

Amendinent License No. DP No. k- 4

1. The Nuclear Regulatory Commission (the Comission) has found that:  !

A. The &pplication for amendment by Sacramento' Municipal Utility District (the licensee) dated February 28, 1986, as revised May 14, 1987, and August 31, 1988, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and tne Comission's. i regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the regulations of the Comission; C. There is reasonable assurance (1) that the activities authorized by this amendment can be conducted without endangering the health and safety of the. public, and (ii) that such activities will be concucted in compliance with the Commission's regulations; i

D. The issuance of t,his amendment will not be inimick1 to the comon i defense and security or to the health and safety of the public; and i E. The issuance of this amendment is in accordance with 10 CFR Part 51 j of the Comis'sion's regulations and all applicable requirements have been satisfied.

2. Accordingly, the license is amended by changes to the Technical Specifica-tions as indicated in the attachment to this license amendment, and para-graph 2.C.(2) of Facility Operating License No. DPR-54 is hereby amended to read as follcws:

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(2)TechnicalSpecifications The Technical Specihcations contained in Appendices A and B, as revised through Amendment No.112, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

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3. This license amendment shall become effective within 30' days of the issuance date. -The implementation delay-is provided to allow time for modification of affected procedures and promulgation of the changes to personnel.

FOR THE NUCLEAR REGULATORY COMMISSION M

George W. Knighton, Director Project Directorate V Division of Reactor Projects III, IV, V and Special Projects

Attachment:

Changes to the Technical Specifications

- Date of Issuance: July 17,1989

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ATTACHMENT TO LICENSE AMENDMENT N0.112 FACILITY OPERATING LICENSE NO. DPR-54 DOCKET NO. 50-312 Replace the following pages of the Appendix "A" Technical Specifications with the. attached pages. . The revised pages are identified by Amendment number and contain vertical lines indicating the area of change.

Remove _ Insert 3-39 3-39 3-40 3-40 3-40a 3-40a 3-40b t

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I RANCHO SECO UNIT 1

., TECHNICAL SPECIFICATIONS Limiting Conditions for Operation 3.6 REACTOR BUILDING Aeolicabilitv l

. All modes from HEATUP-COOLDOWN through POWER OPERATION, inclusive.

Obiettive To, assure containment integrity.

Seetification 3.6.1 Containment integrity shall be maintained.

Action Without primary CONTAINMENT INTEGRITY, restore CONTAINMENT INTEGRITY within one hour or be in at least HOT SHUTDOWN within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDDHN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

3.6.2 Containment integrity shall be maintained when the reactor coolant system is open to the containment atmosphere and the requirements for a refueling shutdown are not met.

3.6.3 Positive reactivity insertions which would result in the reactor being suberitical by less than 1 percent Ak/k shall not be made by control rod motion or boren dilution whenever the containment integrity is not intact. -

3.6.4 The reactor shall not remain critical if the Reactor Building interns 1 pressure exceeds 1.5 psig or vacuum exceeds -1.5 psig.

3.6.5 Prior to criticality following refueling shutdown, a check shall be made to confirm that all manual containment isolation valves which ,

l should be closed are closed. 1

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3.6.6 The containment isolation valves specified in Table 3.6-1 shall be OPERABLE with closure times'as shown in Table 3.6-1.

If, under reactor critical operating conditions an automatic containment isolation valve is determined to be inoperable, the other containment isolation valve in the line shall be tested to ensure operability. If the inoperable valve is not restored within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> 'the reactor shall be brought to the cold shutdown condition within an additional 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or the valve will be placed in a safety features position.

3-39 Amendment No. 2I,97,16f, 112

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l RANCHO SECO UNIT 1 TECHNICAL SPECIFICATIONS Limiting Conditions for Operation Table 3.6-1 CONTAINMENT ISOLATION VALVE $

- NORMAL (1) MAXIMUM AUTO OPERATING CLOSURE VALVE NUMBER DESCRIPTION Ep51 TION 11Q(2 TIME. str.

SFV-22009 RC System Letdown AB Side YES OPEN 25 SFV-22023 RC System Letdown, RB Side YES OPEN 25 STV-24004 RC Pump Seal Return, RB Side YES OPEN < 60 SFV-24013 RC Pump Seal Return AB Side YES OPEN 12 SFV-46014 RB CCW Supply. AB Side NO OPEN 14 SFV-46203 RS CCN Return, RB Side NO OPEN 14 SFV-46204 RB CCW Return, AB Side NO OPEN 1B SFV-46906 CRD Cooling Water Supply, AB Side NO OPEN

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13 1 SFV-46901 CRD Co61ing Water Return, R6 Side NO OPEN 14 SFV-46908 CRD Ceoling Water Return, AB Side NO OPEN 11 SFV-53503 RB Purge Inlet, AB Side YES CLOSED (2) 25 SFV-53504 RB Purge Inlet, RB Side YES CLOSED (2) 25 SFV-53603 RB Press. Equalizer, RB Side YES CLOSED 25 SFV-53604 Rd Purge Outlet, AB Side YES CLOSED (2) 25 SFV-53605 RB Purge Outlet, RB Side YES CLOSED (2) 25 SFV-53610 RB Press. Equaltier, AB Side YES CLOSED 25 SFV-53612 RB Atm. Purge Sample AB Side YES OPEN 25 SFV-53613 RB Atm. Rad. Sample, AE Side YES OPEN 25 SFV-53615 Reactor Building Hydrogen Purge YES OPEN 25 SFV-53616 Reactor Building Hydrogen Purge YES OPEN 25 SFV-60001 RC System Vent Isol., RB Side YES OPEN 25 SFV-60002 RC System Vent Isol., AB Side YES OPEN 25 '

SFV-60003 RC System Drain Isol., AB Side YES OPEN 25 SFV-60004 RC System Drain Isol., AB Side YES OPEN 25 SFV-66308 RB Normal Sump Drain, AB Side TES OPEN 25 SFV-06309 RB Normal Sump Drain, AB Side YES ODEN 25 i

SFV-70001 Przt. Liquid Sample Itol., RB Side YES CLOSED 25 SFV-70002 Przt. Liquid Sample Isol., AB Side YES CLOSED 25 SFV-70003 Prrr. Vapor Sample Isol., RB Side YES CLOSED 25 SFV-72501 Przr. Gas Sample Isol., RB Side YES CLOSED 25 i SFV-72502 Prrr. Gas Sample Isol., AS Side YES CLOSED 25 SFV-92520 Prrr. Nitrogen Isol., AB Side YES CLOSED 25 i

(1) Valves without auto-isolation may De open provided the ecntrols for the respective valve are attended by an operator. Auto-isolation valves may be in any position.

(2) See Section 3.6.7

. l Amendment No. 31, '/2, 87, 112 3-40

RANCHO SECO UNTT 1 TECHNICAL SPECIFICATIONS Limiting Conditions for Operation Table 3.6-1 (Continued)

CONTAINMENT ISOLATION VALVES NORMAL (1) MAXIMUM AUTO OPERATING CLOSURE-VALVE NUMBER DESCRIPTION R POSITION TIME. sec.

HV-20593 OTSG-A Sample Isol., AB Side NO CLOSED 12 HV-20594' OTSG-B Sample Isol., AB Side NO CLOSED 5 HV-20609 OTSG-A flowdown Isol., RB Side NO CLOSED 15 HV-20610 OTSG-B Blowdown Isol., RB Side NO CLOSED 14 HV-20611 OSTGs Blowdown Isol., AB Side NO CLOSED 22 HV 53617 Reactor Building Hydrogen Purge NO CLOSED 25 HV-53618 Reactor Building Hydrogen Purge NO CLOSED 25 HV-70040 Hydrogen Monitor Containment Outlet Isol. NO CLOSED 25 HV-70041 Hydrogen Monitor Containment

< Inlet Isol. NO CLOSED 25 HV-7G042 Hydrogen Monitor Containment Inlet Isol. NO CLOSED 25

, HV-70043 Hydrogen Monitor Containment Outlet Isol. NO CLOSED 25 HV-70044 Hydrogen Monitor Centainn.ent Outlet Isol. NO CLOSED 25 HV-70045 Hydrogen Monitor Containment Inlet Isol. NO CLOSED 25 HV-70046 Hydrogen NJ:dtor Containment Inlet Isol. NO CLOSED 25 HV.,70047 Hydrogen Monitor Containment OVtlet Isol. NO CLOSED 25 l

l (1) Valves without auto-isolation may be open provided the controls for the i respective valve are attended by an operator. Auto-isolation valves may be in any position.

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Amendment No. 112 3-40a

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RANCHO SECO UN8T 1 TECHNICAL SPECIFICATIONS Limiting Conditions for Operation 3.6.7 The Reactor Building Purge Valves, SFV 53503, SFV 53504, SFV 53604, and SFV 53605, shall be closed with their respective breakers de-energized, except during cold shutdown or refueling. Valves SFV 53503 and SFV 53604 shall be verified to be in the above condition at least

. monthly. 'The breakers / disconnects on valves SFV 53504 and SFV 53605 shall be verified to be de-energized at least monthly.

3.6.6 The Reactor Building Purge Valves sha. solate on high containment radiation level. See Table 3.5.1-1 for operability requirements.

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-The reactor coolant system conditions of cold shutdown assure that no steam will be formed and hence no pressure buildup in the containment if the reactor coolant system ruptures.

The selected shutdown conditions are based on the type of activities that are being carried out and will preclude criticality in any occurrence.

The Raatter Building is designed for an internal pressure of 59 psig and an external pressure 2.0 psi greater than the internal pressure. The design external pressure corresponds to the differential pressure that could be developed if the building is sealed with an internal temperature of 120*F with a barometric pressure of 29.0 inches of Hg and the building is subsequently cooled to an internal temperature of 80*F with a concurrent rise in barometric pressure to 31.0 inches of Hg.

When containment integrity is established, the limits of 10 CFR 100 will not be exceeded should the maximum hypothetical accident occur.

The OPERABILITY of the containment isolation ensures that the containment atmosphere will be isolated from the outside environment in the event of a -

l release of radioactive material to the containment atmosphere by pressurization of the containment. Containment isolation within the time j limits specified for valves which receive an automatic isolation signal ensures that the release of radioactive material to the environment will be consistent with the assumptions used in the analyses for LOCA. Valves which are ,

permitted to be open during plant operation are either part of closed systems I which would not cause releases to the environment, or are administrative 1y controlled to ensure their rapid closure in the event of an accident.

l Specifications 3.6.7 and 3.6.8 are in response to NUREG 0737 item II.E.4.2.

REFERENCE i

(1) USAR, section 5 l l

l Amendment No. 37, 49, 87, 112 l 3-40b l

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UNITED STATES NUCLEAR REGULATORY COMMISSION g -p wAssewcToN. o. c. 20sss

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SAFETY EVALUATION BY THE.0FFICE.0F. NUCLEAR REACTOR REGULATION SUPPORTING. AMENDMENT NO,112TO. FACILITY.0PERATING LICENSE.DPR.54

. RANCHO.SECO NUCLEAR. GENERATING. STATION,. UNIT.1 DOCKET.W0. 50 312 1.0' INTRODUCTION By lecters dated February 28, 1985, May 14, 1987, and August 31, 1988, the Sacramento Municipal Utility District, the licensee for the Rancho Seco Nuclear Generating Station, proposed Technical Specification (TS) changes to Appendix A of Operating License DPR-54 for Rancho Seco. The proposed changes were requested to revise the. Rancho Seco TS Table 3.6-1, " Safety Festures Containment Isolation Valves" to add 12 new valves into the table and to increase the valve closure time to 25 seconds for all valves listed in the table, in:1uding new valves.

The current TS Table 3.7-1 lists 35 safety features containment isolation valves with required maximum valve closure times ranging from 3 to 22 seconds. The proposed amenoment adds 12 valves to the table, each with a 25-second closure time, ano increases the valve closure time to 25 seconds for 23 selected valves.

The remaining 12 valves (out of 35 valves currently listed in the table) have not; changed the maximum allowable closure time in the proposed amendment. All of these safety features isolation valves offer a direct pathway from the containment to the environment.

2.0 EVALUATION In this evaluation, the staff grouped 35 isolation valves (23 selected valves from the current table plus 12 newly added valves) as follows:

1. Reactor Building Purge Valves (4 valves)

2. Valves with no automatic isolation features (remote-manual operation) and normally in closed position (10 valves)

3. Valves with automatic isoletion features and normally in either closed or open position (21 valves) 2.1 Reactor Buildino. Inlet.and. Outlet. Purge. Valves-(SFV.53503, SFV-53504, 5FV-53604, and.5FV.53605)

These four reactor building inlet and outlet purge valves are administrative 1y locked closed. The Rancho Seco TS Section 3.6.7 states that the purge valves should be closed with their respective breakers de-energized, except during i

cold shutdow or refuelir.g. It further states that the valve position should '

be verified at least monthly. Tt.erefore, the valve closing time for these purge valves are only relevant to a postulated fuel handling accident during ,

refueling operation.

.- The staff reevaluated the offsite radiological consequences due to the increased valve closure time (25 seconds) tollowing a postulated fuel handling accident.

In the Rancho Seco Safety Evaluation Report (SER) dated June 1973, the staff previously evaluated a postulated fuel handling accident using assumptions stated in Section 15.3 of the SER. In this evaluation, the staff calculated the incremental offsite doses attributable to the delayed valve closure time (25 seconds) using the same assumptions used in the previous analysis. The SER does ,not state the valve closure time used previously and therefore, the l staff assumed that the zero valve closure time was used. l The staff's calculated offsite doses resulting from 25 second valve closure time following a postulated fuel handling accident inside containment are presented in the attached Table 1 aiong with previously calculated offsite doses due to the accident.- At. shown in the table, the potentia'l overall offsite doses for a postulated fuel handling accident including incremental doses attributable to the delayed valve closure tine of 25 seconds are still within the acceptance criterin specified in the Standard Review Plan (SRP)

Section 15.7.4. Therefore, the staff finds that the proposed valve closure time of 25 seconds is acceptable.

2,2 V61ves With No Automatic. Isolation. Features (Remote Manual.0peration) and hormally in Closed Position (10 41ves).

1. HV-53617 Reactnr Builcing Hydrogen Purge Line

2. HV-53618 Reactor Building Mydrogen Purge Line

3. HV-70040 Hydrogen Monitoring Isolation Line

4. HV-70041 Hydrogen Monitoring Isolation Line

5. HV-70042 Hydrogen Monitr ing Isolation Line

6. HV-70043 Hydrogen Monitoring Isolation Line

7. HV-70044 Hydrogen Monitoring Isolation Line

8. HV-70045 Hydrogen Monitoring Isolation Line

9. HV-70046 Hydrogen Monitoring Isolation Line

10. HV-70047 Hydrogen Monitoring Isolation Line The above valves are normally clossd, remately-operated one-inch diameter hand valves. The operation of these valves is administratively controlled. An operator is in attendance wherever these valves are operated for the purpose of sampling and surveillance. Otherwise, the valves remain in a closed position. The licensee statec in the preposed amendment that these valves were installed in 1983 as a part of the Post Accident Sampling System.

Therefore, the potential offsite doses are not relevant to and not affected by ',

l the increased valve closure time (25 secor.ds) of these normally closed valves.

The valve closure times are only specified and added to the table since they l are qualified and designated as containment isolation valves. Therefore, the l staff finds that the increased closure times for these valves are acceptable. j 2.3 All Other Renainina Valves (21. Valves)

These valves are normally in either the closed or open position with automatic isolation features.  ;

s In the proposed amendment, the licensee mndeled, for the purpose of estimating the mass flow rate expected from the containment to the environment following the receipt of a LOCA signal, all 10 containment penetrations (one 6" RC System Drain. two 4" RB Sump Drain and RC Pump Seal Water Return, one 3" RC System Vent, one 21/2" RS System Letdown, four 1" sample lines, and one 3/4" sample Ifne) with their 19 isolation valves (except ou 12-inch reactor building pressure equalizer line with two isolation valves) as one large penetration (10-inch) having an equivalent cross sectional area. The licensee estimated average mass flow rates from time zero to 25 seconds to be approximately 2.4 x 104 and 1,8 x 104 it3 through the 12-inch reactor building pressure equalizer line and one 10-inch modeled line respectively. The staff used the LOCA blowdown mass re16ase rate of 4.9 x 205 lbs for the first 25 seconds as given in the Rancho Seco USAR Table 14.4-4 The Rancho Seco USAR Figures 14.2-31 and 14.2-32 show peak fuel cladding temperature (hot spnt) as a function of time after a LOCA for an 8.55 ft2 double-ended break in cold leg pipe at the reactor feed pump discharge. The licensee stated that this break resulted in the highest calculated fuel cladding temperature. According to these figures, the cladding temperature of approximately 2000*f. will be reached at 25 seconds after a LOCA. A maximum hot spot cladding temperature of 2299'F. at 38.5 seconds was calculated by the licensee meeting the NRC Interim Criteria of 2300*F. used in 1973 (this limit has since been lowered by 10 CFR 50.46 to the current valve of 2200 F.).

i Some of the fuel rods may be expected to experience cladding perforation-deformation failure due to the heatup transient (fuel-cladding temperature excursion) during the first 25 seconds after a LOCA. Therefore, the staff used, in accordance with SRP 6.2.4, an iodine spike of 60 mci /gm (dose equiva-lent iodine-131) in the LOCA blowdown as source term. The source term activity I will be innediately available for release through the containment isolation valve pathways (ont 12" reactor building squilizer line and one 10" modeled line opening) .for the first 25 seconds after the receipt of a LOCA signal. No credit was given for removal of fission products in the staff's analyses (containment spray, charcoal absorbers, iodine partition, iodine plate-out, 6 etc.).

The staff's calculated offsite doses resulting fron,25 second valve closure time following a LOCA are also cresented in Table 1 along with previously calculated offsite doses due to the LOCA as shown in the SER Table 15.0. As shown in Table 1, the potential overall offsite doses for a LOCA including

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incremental doses attributable to the delayed valve closure time of 25 seconds j are still within the dose reference values specified in 10 CFR Part 100.

c Therefore, the staff finds that the proposed valve closure time of-25 seconds-is acceptable.

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SUMMARY

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Based on 'our review, we find that calculated offsite doses including 1peremental doses attribut3ble to the increased valve closure time are still within the exposure reference guidelines of 10 CFR Part 100 and are within the acceptance criteria giyen in Standard Review Plan Section 15.7.4. Therefore, we find the 1 proposed changes to the Rancho Seco TS concerning the safety features contain-ment. isolation valve closure time are acceptable.

4.0 CONTACTWITHSTATEOFFICIAJ The NRC staff has advised the Chief of the Radiological Health Branch, State Department of Health Services, State of California, of the proposed determination  ;

of no significant hazards consideration. No concents were received.

5.0 ENVIRONMENTAL CONSIDERATION

This amendment involves changgs ir. the installation or use of a' facility. com-ponent located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no'significant increase in the' amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual

.or cumulative. occupational radiation er.posure. The Commission has previously issuea a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, this amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b),'no environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.

6.0 CONCLUSION

We have concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safet of the public will not be endangered by operation in the proposed manner,2 (y) such activities will be -

conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to common cefense and secprity or to the health and safety of the public. -

Principal Contributor: J. Lee Dated: July 17, 1989 1

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-Table 1 Potential Offsite Doses Du_e to Desion Basis Accidents Exclusion Area Low Population Accidents' Boundary Zone (rem) (rem)

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- Thyroid Whole Body Thyroid Whole Body Fuel Handling! 34 4 2 Purge Valves <1 2 <1 <1, <1 Total 36 <5

<3 <2 SRP Criteria Limit 75 6 75 6 Lois'of Coolant! 267 8 48 1 Delayed Valve Closures 22 <1 3 <1 Total 289 <9 51 <2

- 10 CfR 100 Limit 300 25 300 25 2SER Table 15.0 225 second valve closure time f

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