ML20057B107

Safety Evaluation Supporting Amends 164 & 195 to Licenses DPR-71 & DPR-62,respectively

ML20057B107
Person / Time
Site:	Brunswick
Issue date:	09/14/1993
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20057B105	List: ML20057B104 ML20057B107
References
NUDOCS 9309170194
Download: ML20057B107 (10)

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W A SHINGTON. D.C. 00555-0001 SAFETY EVALVATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. IfA TO FACILITY OPERATING LICENSE NO. DRP-71 AND AMENDMENT NO.195 TO FACILTY OPERATING LICENSE N0. OPR-62 CAROLINA POWER & LIGHT COMPANY BRUNSWICK STEAM ELECTRIC PLANT. UNITS 1 AND 2 DOCKET NOS. 50-325 AND 50-324

1.0 INTRODUCTION

By letter dated December 31, 1992, as revised by letter dated July 20, 1993, and supplemented by letters dated August 9, 1993, and August 27, 1993, Carolina Power and Light Company (CP&L or the licensee) requested an amendment to the service water system (SWS) Technical Specifications (TSs) for the Brunswick Steam Electric Plant, Unit Nos. I and 2 (BSEP). The July 20, August 9, and August 27, 1993, letters provided changes and additional information that were not outside the scope of the initial determination of no significant hazards consideration as ptiolished in the Federal Beaister.

The amendment request proposes revision of the number of nuclear service water pumps (NSWPs) required to be.,perable from two NSWPs per unit to three NSWPs serving the site whenever either unit is in operational condition 1, 2, or 3, revision of the action statements associated with certain SWS pump configurations in all operational conditions, incorrioration of TS surveillance 4.7.1.2.c into proposed action b.4 of TS 3.7.1.2, addition of a quarterly surveillance of the pressure switch logic and valve actuation capability associated with the SWS supply to the emergency diesel generators (EDGs), and complete revision of the bases for TS 3/4.7.1.2.

The proposed TS revision is associated with a recent plant modification to upgrade the thrust bearing capacity of the NSWP motors.

Prior to the modification, the pump motor's thrust bearing could fail due to overloading under low pump flow conditions.

In order to prevent this condition, a minimum flow path had been maintained to ensure adequate pump flow under all credible accident conditions. With the upgrade to the pump motor's thrust bearing, the licensee has determined that the NSWPs are capable of withstanding all credible low flow conditions. Therefore, the minimum flow path is no longer required to prevent pump damage.

In addition, the licensee determined by analysis that, without the minimum flow path, any two operating NSWPs are sufficient to ensure adequate cooling to the four EDGs under all credible conditions.

The third operable NSWP serving the site, which is required by the proposed TS Limiting Condition for Operation (LCO), is assumed to be disabled by the design basis single failure.

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2.0 BACKGROUND

The BSEP SWS provides water for lubrication and cooling of selected systems and components.

The SWS serving each unit is subdivided into two major headers, nuclear and conventional, which are normally operated independently.

The nuclear header normally is aligned to supply cooling water to the reactor building closed cooling water (RBCCW) system heat exchangers.

The conventional header normally supplies service water to the turbine building closed cooling water (TBCCW) system and certain balance-of-plant equipment in other areas.

The conventional header is capable of being aligned to supply the RBCCW heat exchangers in place of the nuclear header.

For each unit, two nuclear s'ervice water pumps (NSWPs) are dedicated to supply the nuclear header, and three conventional service water pumps (CSWPs) are normally available to supply the conventional header.

However, the CSWPs can be individually aligned by operator action to discharge directly to the nuclear header instead of the conventional header.

Each NSWP is powered from a separate emergency bus.

Two of the three CSWPs associated with each unit are powered from the same two emergency buses powering the NSWPs associated with that unit.

The remaining CSWP is powered from an emergency bus associated with the opposite unit.

Due to this configuration, a single failure of an emergency bus may result in the loss of one NSWP and one CSWP from the same unit and the loss of a CSWP from the opposite unit.

Standby NSWPs and standby CSWPs start automatically on low header pressure.

In addition, all NSWPs start automatically on a loss of coolant accident (LOCA) signal or a loss of offsite power (LOOP) signal.

However, the CSWPs must be started manually following a LOCA or LOOP.

The four EDGs are the only SWS loads common to both units.

Two EDGs are normally supplied from each unit's nuclear header, but low service water supply pressure sensed by a pressure switch at an EDG causes the service water supply to that EDG to automatically transfer to the opposite nuclear header.

The transfer logic permits only a single transfer per EDG, regardless of the service water supply pressure provided following the first transfer.

A LOCA signal or a LOOP signal generates an EDG start signal and automatically opens the service water supply valve to the jacket water cooler.

Other safety-related loads associated with each unit include the residual heat removal service water system (RHRSW) pumps, core spray (CS) and residual heat removal (RHR) pump room coolers, RHR pump seal heat exchangers, lubricating water for the SWS pumps, and cooling water for the RHRSW pump motors.

The vital service header supplies the pump room coolers and pump seal heat exchangers.

The RHRSW pumps take suction directly from a separate header and are started remotely.

The RHRSW pumps have a low suction pressure trip. The vital service and RHRSW suction headers are connected to both the conventional and nuclear headers, and the vital service and RHRSW suction headers can be aligned, using remotely operable valves, in configurations where cooling water is supplied by the nuclear header alone, the conventional header alone, or a combination of the nuclear and conventional headers such that each header serves one train.

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-N{ltc".% L l? __ 's l.4 _,..in + ~ 3 ' The valves controlling flow from the vital service header to the individual components served by the vital header are air-operated, and these valves are assumed to fail.open due to loss of the unqualified service air compressors following a LOCA or LOOP. The two motor operated header isolation valves for each unit, individually supplying service water from the nuclear header to the vital service and RHRSW suction headers, are powered from a single emergency bus, and this emergency bus is separate from the emergency bus supplying power to the header isolation valves on the conventional header. Portions of the SWS which are not safety-related are capable of being isolated from the safety-related portions by redundant, electrically independent, motor operated valves. The service water supply from the unit nuclear header to the RBCCW heat exchangers is -automatically isolated by redundant valves on a LOCA signal or LOOP signal for that unit. Leakage across the isolation valves between the nuclear and conventional headers piping has been identified when one of the two headers is depressurized. 3.0 EVALUATION 3.1 Limiting Conditions for Operation The licensee's letter dated' July 20, 1993, included the following as ~ attachments: " Service Water System Hydraulic Analysis Report" (containing calculations G0050A-16, Rev.1, and G0050A-18, Rev. 0), " Analysis for Tech Spec 3.7.1.2 Proposed Change" (OSW-0048, Rev. 0), " Unit 2 Hydraulic Analysis" (G0050A-12, Rev. 5), and " Unit 1 Hydraulic Analysis" (G0050A-10, Rev. 5). ~These analyses are based on the licensee's computer models of the SWS using the KYPIPE hydraulic analysis code, and they document the calculated hydraulic performance of the SWS under the pump configurations permitted for continuous operation under the proposed revi: ions to TS 3.7.1.2 which the licensee determined to be limiting. The test procedures, test data, and engineering evaluations used in the latest validation of the service water system computer models were submitted as attachments to a letter dated August 9,1993. A description of the methodology used to validate the computer models and the results of additional analyses verifying the capability of a single CSWP to supply adequate cooling water for long term decay heat removal were provided in a letter dated August 27, 1993. During the first 10 minutes of a design basis event, the EDGs and the service water pump lube water system are the only loads which must be supplied by the service water system. The licensee's analyses assume that the vital service header loads also receive cooling water flow during the first 10 minutes of a LOCA and during the first 10 minutes of a LOOP, if that assumption is most restrictive. After the init-lal 10 minute period, the SWS must provide cooling to other essential loads to support long term decay heat removal. The 19 minute pericd where no operator action or assistance is allowed was established as the design basis for all' engineered safety features by CP&L's response to an Atomic Energy Commission. staff question during review of the original BSEP Final Safety Analysis Report. The 10 minute period also coincides with the analyzed' time for manual initiation of the containment cooling mode of RHR presented in the Updated Final Safety Analysis Report. The' containment cooling mode of RHR requires the operation of the RHRSW system. i MO S 4 The proposed TS revision for the SWS requires three NSWPs serving the site and two CSWPs associated with each unit initially operable in operational conditions 1, 2, and 3. From this initial configuration, assuming a single failure, at least two site NSWPs will remain operable to support operation of the EDGs, and at least one service water pump for each unit in operational condition 1, 2, or 3 will re~ main operable to support long-term decay heat removal after the first 10 minutes of the event. Necessary pump, header, and valve alignments for long-term decay heat removal can be made by remote operator action. However, manual operator action within the reactor building is not credited because of the potential for unsafe conditions in the reactor building following a LOCA. In operational conditions 1, 2, and 3, a CSWP must be capable of supplying cooling water to both the nuclear header and the c)nventional header to be considered operable. This will ensure that the vital service header and the RHRSW suction header can be supplied from either the nuclear or conventional header when a single failure is assumed which results in inoperability of any header isolation valve and personnel access is not available for manual valve alignment. In operational condition 4 or 5, three NSWPs serving the site and a total of at least two service water pumps (nuclear or conventional) powered from separate emergency buses and capable of supplying the nuclear header are required by existing TS 3.7.1.2. The three initially operable NSWPs ensure that two NSWPs are available to provide cooling water flow to the EDGs following a single failure. Two operable service water pumps powered from separate power supplies for each unit in operational condition 4 or 5 ensure that at least one service water pump for decay heat removal will remain operable following a single failure. Necessary pump, header, and valve alignments to support operat'ing equipment can be made by remote or manual operator action. The staff reviewed the results of the licensee's SWS analyses, which were provided as attachments to the letter dated July 20, 1993, and found that all potential system configurations were evaluated. The licensee adequately justified the limitig accidents and single failures considered in the analyses. However, the staff noted that a qualitative analysis which was intended to show that a single CSWP is capable of supplying sufficient cooling water flow after the first 10 minuus of a design basis event was based on an inadequately justified assumption. In response to staff concerns regarding this assumption, the licensee provided the results of a quantitative analysis in their letter dated August 27, 1993. This analysis demonstrated that a single CSWP is capable of providing adequate cooling water flow after the first 10 minutes,f a design basis event using the computer models of the SWS. Acceptance crite:la used in evaluating the limiting configurations were based on achieving acceptable cooling water flow to all components and maintaining adequate net positive suction head for the operating service water pumps. The acceptance criteria include an allowance for a five percent deviation from the calculated flow in order to provide margin for inaccuracies in the computer model s. Each SWS configuration was evaluated at the design high and low bay levels. If both units were assumed to be in operational condition 4 or 5, extreme low bay level and flood levels were also evaluated. High energy line breaks such as a LOCA were not considered credible for evaluation for units in $^ 5 operating conditions 4 and 5. The evaluation also included an allowance for leakage into a depressurized header. In configurations where an unacceptable condition was calculated to exist, an automatic function, such as transfer of one or more EDGs to the opposite nuclear header on low service water header pressure or low RHRSW suction header pressure trips of one or more RHRSW pumps, was calculated to occur. The licensee determined that these automatic functions would restore the SWS to a configuration with acceptable component flow and adequate net positive suction head. The staff found the acceptance criteria used in the evaluation and the scope of the evaluation to be acceptable. The staff also reviewed the test procedures, test data, and engineering evaluations used in the most" recent validation of the SWS computer models. The most rec nt test procedures collected flow data from just three configurations where all components received flow. However, the licensee indicated that the SWS computer model was developed and refined using test data collected for seven different configurations. The configurations tested included conditions where one or two NSWPs were operating, two or four EDGs were aligned to the header, and with the two RHRSW booster pumps in operation or secured. The most recent. tests were used to verify the accuracy of the model in predicting the flow through safety-related components served by the nuclear header. Although the computer models were developed from test data where the NSWPs are supplying only the nuclear header, the licensee determined that the model results are applicable to all system configurations based on the similarity of the piping arrangement for the nuclear and conventional headers and the performance similarity of the service water pumps. Based on the licensee's statements regarding the validation of the computer models to test results for a number of system configurations and the licensee's determination that the computer models developed for the nuclear header l configuration are also applicable to the conventional headers, the staff concluded that an adequate basis was established to support use of the computer models for system flow verification. Based on the engineering evaluations used in the most recent validation of the SWS computer models, the staff concluded that the five percent margin applied to the calculated cooling water flow rates is acceptable. The engineering evaluations and computer models are subject to design review in accordance with CP&L's quality 4 assurance program. Overall, the staff found the licensee's evaluation in support of the proposed TS revision acceptable. Since the evaluation demonstrates that SWS configurations following limiting single failures satisfy the licensee's acceptance criteria with regard to component cooling water flow and service water pump net positive suction head, the proposed limiting conditions for operation of the SWS are acceptable. 3.2 Action Statements A summary of the proposed action statements associated with the limiting conditions for operation under TS 3.7.1.2 for a single unit is provided below: a. In Operational Conditions 1, 2, and 3: _.. _. _ _ _ ~. _. _ _ ~ \\ 6 1. With one operable CSWP, if only one NSWP associated with the same unit is operable, ensure that the operable CSWP is powered from a separate emergency bus than the operable NSWP, and restore one additional CSWP to operable status within 7 days. Otherwise, be in at least hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. 2. With no operable CSWPs, ensure both NSWPs associated with the same unit are operable, and restore at least one CSWP to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Otherwise, be in at least hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. 3. With two operable site NSWPs, unless the provisions of action b.4 for operational conditions 4 and 5 apply for the opposite unit, restore one additional site NSWP within 7 days. Otherwise, be in at least hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the i following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. 4. With two operable site NSWPs and one operable CSWP, ensure that at least one NSWP associated with the same unit is operable and that the operable CSWP is powered from a separate emergency bus than the operable NSWP, if only one NSWP associated with the same unit is operable, and restore two CSWPs or three site NSWPs to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Otherwise, be in at least hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. l 5. With less than two operable site NSWPs, be in at least hot shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in cold shutdown within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. b. In Operational Conditions 4 or 5: 1. With one operable service water pump, restore at least two service water pumps to operable status within 7 days. Otherwise, suspend all operations that have a potential for draining the reactor vessel. 2. With no operable service water pumps, suspend all operations that have a potential for draining the reactor vessel. 3. With two operable site NSWPs, unless the provisions of action 4 below apply, restore at least one additional NSWP to operable status within 7 days. Otherwise, take the action required by TS 3.8.1.2. 4. With the SWS nuclear header inoperable, operation of both units may continue provided that two NSWPs associated with the opposite unit are operable, nuclear header valves are administratively controlled to ensure adequate cooling water to the EDGs, at least two CSWPs associated with the unit are operable on the conventional header, j and vital service header loads are aligned to the conventional header. Restore the nuclear header and three site NSWPs to operable i 7 status within 14 days. Otherwise, take the action required by TS 3.8.1.2. S. With less than two operable site NSWPs, take the action required by TS 3.8.1.2. For action a.1, given the provision requiring separate power supplies for two of the remaining operable service water pumps, an additional single failure may cause a loss of SWS functional capability only from a particular configuration of operable service water pumps. Three operable site NSWPs ensure that adequate cooling will be maintained for the EDGs following any single failure. However, assuming that there is one operable NSWP associated with the unit and that the operable CSWP is powered from the same emergency bus as the header isolation valves supplying service water from the nuclear header to the vital service and RHRSW suction headers, a failure of the emergency bus supplying the CSWP and nuclear header isolation valves would result in a loss of service water to the vital service and RHRSW suction headers from the operable NSWP. The nuclear header isolation valves are assumed to be inaccessible for manual operation following a LOCA, and power for remote operation would not be available. The staff determined that other configurations result only in a reduction in the degree of redundancy. In consideration of the low probability of a failure of a specific emergency bus and the general reduction in redundancy while in the pump configuration-described above, the proposed 7 day allowed outage time for action a.1 is acceptable. For action a.2, only two NSWPs are available to support the unit's service water loads. In this configuration, failure of the nuclear header isolation valves or their power supply results in a loss of the functional capability of the SWS to mitigate a LOCA. Due to the greater probability of this failure, a shorter allowed outage time is justified relative to action a.l. However, the probability of these particular failures occurring within a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> period remains acceptably small. Therefore, the proposed allowed outage time is acceptable. With only two operable site NSWPs as specified in action a.3, an additional single failure of a NSWP may result in inadequate EDG cooling for the first 10 minutes of a design basis event, depending on the initial configuration of the SWS and the temperature of the cooling water. Providing electrical power is available, the capability of the SWS to mitigate the effects of a LOCA remains i assured. Since the result of the additional single failure is only an-increase in the probability of one or more EDG failures during the 10 minute period during a design basis event before operator action is credited, the staff considers the risk acceptably small to justify the proposed 7 day allowed outage time. The provisions of action b.4 ensure that two NSWPs associated with the operating unit are operable. In this particular configuration, the licensee has demonstrated that adequate EDG cooling can be maintained following an additional single failure. Therefore, the proposed exemption from the provisions of action a.3 for the operating unit is acceptable when the provisions of action b.4 apply to the opposite unit. l t i 8 The SWS configuration specified in action a.4 is susceptible to the potential failures described in the reviews of action a.1 and action a.3 above. Since these potential failures are both low probability events and affect separate functions of the SWS, the proposed 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time is acceptable. With less than two operable NSWPs, as specified in action a.5, the probability of failure of one or more EDGs due to inadequate cooling is significant. Therefore, prompt action is necessary to place the plant in an operating condition where the need for electrical power is minimal. Similarly, if action has not been completed to correct a deficient condition within the allowed outage time, the plant should be placed in a condition where the need for service water is minimized. Based on these considerations, the staff found the proposed requirement to place the plant in hot shutdown (operational condition 3) within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and cold shutdown (operational condition 4) within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to be acceptable if less than two site NSWPs are operable or if the required corrective action is not completed within the allowed outage time. Action b.1 and action b.2 specify actions when the decay heat removal capability of the SWS is degraded. With one operable service water pump, the propostJ 7 day allowed outage time is acceptable based on the low probability of failure of the operable service water pump in that seven day period. The proposed action statements require suspension of operations with the potential for draining the reactor vessel in operational conditions 4 and 5 when corrective action to restore a second service water pump to operable status is not completed in the allowed time or when no operable unit service water pumps are available. This action statement is acceptable because the probability that an adequate volume of water will be retained in the reactor vessel for decay heat removal is increased while the SWS is degraded. Action b.3, action b.4 and action b.5 similarly specify actions when the EDG cooling function of the SWS is degraded. With two operable site NSWP, the proposed 7 day allowed outage time of action b.3 is acceptable based on the low probability of further degradation which would impact the EDG cooling j function of the SWS. With the SWS aligned in accordance with the provisions of action b.4, the proposed 14 day allowed outage time is acceptable based on the somewhat greater reliability of the SWS satisfactorily performing the EDG l cooling function in that configuration as a result of the administrative 1 control of nuclear header valve positions. If the allowed outage times of d action b.3 or action b.4 are not satisfied, or if less than two site NSWPs are operable, the proposed action requires suspension of operations involving irradiated fuel handling, core alterations, positive reactivity changes, or operations having the potential to drain the reactor vessel. This suspension is acceptable in operational conditions 4 and 5 when the EDG cooling function of the SWS is degraded since the probability of electrical power being necessary to support safety system actuation in response to an accident or transient is reduced. I 3.3 Other Technical Specification Revisions With only three operable site NSWPs required by the proposed limiting condition for operation in operational conditions 1, 2, and 3, the capability l i /> s 9 to automatically transfer the service water supply to the EDG jacket water coolers from one unit's nuclear header to the opposite unit's nuclear header is important. This feature prevents a single failure resulting in a loss of cooling water from disabling one or more EDGs during the first 10 minutes of a design basis event. The licensee determined that the dominant contributor to a loss of EDG cooling is a failure of the primary and backup inlet valves to open on demand from their normally closed positions. Based on this determination, the additional reliance on the service water header transfer feature results in a negligible increase in the p;unability of a loss of cooling to one or more EDGs. However, in order to enhance the reliability of the transfer logic and backup inlet valve operation, the licensee proposed adding a quarterly functional test of these components to the surveillance requirements of TS 4.7.1.2. Since operation of these components is necessary to ensure the functional capability of the SWS following a design basis single failure, the staff considers a periodic functional test necessary. Therefore, the proposed additional surveillance requirement is acceptable. The existing surveillance requirement of TS 4.7.1.2.c is entered when the nuclear header of a unit is inoperable. Since the surveillance requirement is required to be performed based on the existence of a degraded system condition, the licensee proposed moving the actions specified by this surveillance requirement to action statement b.4 of TS 3.7.1.2. Because the nature of the required actions is consistent with that of an action statement, the staff concludes that the proposed change is acceptable. Although the bases for TS 3.7.12 do not require specific staff approval, the staff reviewed the revised bases submitted by the licensee. The staff found the bases to be consistent with the analyses used to support the proposed changes to TS 3.7.1.2. Other changes were found to be purely administrative in nature and are acceptable without further review. 4.0

SUMMARY

The licensee has confirmed by analyses that the BSEP SWS, with recent modifications to the NSWP thrust bearings and RBCCW header isolation valves, is capable of performing its safety function in accordance with the requirements of General Design Criterion 44 of Appendix A to 10 CFR Part 50 when it is aligned in a configuration corresponding to the proposed limiting condition for operation of TS 3.7.1.2.

The staff reviewed the supporting analyses and concluded that they provide an acceptable basis for the proposed change. Therefore, the proposed change to the limiting condition for operation of TS 3.7.1.2 is acceptable.

The staff also reviewed the proposed action statements of TS 3.7.1.2 and found the required actions acceptable in mitigating the risk associated with operation of a unit with a partially degraded SWS.

The staff concluded that the additional surveillance requirement proposed to periodically test the operation of the EDG service water header transfer logic and backup isolation valve will increase the reliability of this function and ensure that adequate cooling to the EDGs is maintained.

Therefore, the addition of the surveillance requirement of TS 4.7.1.2 is acceptable. Movement of the m

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5.0 STATE CONSULTATION

In accordance with the Commission's regulations, the State of North Carolina official was notified of the proposed issuance of the amendment.

The State official had no comments.

6.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes the Surveillance Requirements. The NRC 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 exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (58 FR 16853).

Accordingly, the 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 the amendment.

7.0 CONC 1USION The Commission has concluded, based on the considerations discussed above, that (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with-the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal contributor:

S. Jones Date:

Septerter 14, 1993 J

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