ML20199C367

Safety Evaluation Supporting Amends 132 & 124 to Licenses DPR-42 & DPR-60,respectively

ML20199C367
Person / Time
Site:	Prairie Island
Issue date:	11/04/1997
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20199C365	List: ML20199C360 ML20199C367
References
NUDOCS 9711190321
Download: ML20199C367 (10)

Text

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UNITED STATES

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NUCLEAR RESULATORY CEMMISSIEN o

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION BELATED TO AMENDMENT NOS.132 AND 124 TO E'ACILITY OPERATING LICENSE NOS. DPR-42 AND DPR-60 NORTHERN STATES POWER COMPANY PRAIRIE ISLAND NUCLEAR GENERATING PLANT. UNIT NOS.1 AND 2 DOCKET N7S. 50-282 AND 50-306

1.0 INTRODUCTION

By letter dated November 27,1996, as supplemented August 15, September 2, and October 3, 1997, the Northern States Power Company (NSP or the licensee) requested amendments to the Technical Specifications (TS) appended to Facility Operating License Nos. DPR-42 and DPR 60 for the Prairie island Nuclear Generating Plant, Unit Nos.1 and 2. The propei ed amendments would allow sleeving of steam generator tubes with sleeves designed by the vendor, ABB Combustion Engineering (CE). Additionally, the proposed TS amendments would establish a repair limit of 31 percent for the pressure boundary of any sleeve and require supplemeritalinspections of sleeved tubes prior to declaring the steam generator tubes operable per TS 4.12, Steam Generator Tube Surveillance.

The August 15 September 2, and October 3,1997, letters provided clarifying information and updated TS pages. This information was within the scope of the original application and did not change the staff's initial proposed no significant hazards considerations determination.

Three types of ABB/CE leak tight sleeves are proposed for use at Prairie Island. Two of the three designs are termed Full Depth Tubesheet (FDTS) sleeves. One FDTS sleeve is welded to the tube near both the upper and lower ends of the sleeve. The second type is welded to the tube near the upper end and a hard roll expansion in the lower tubesheet area secures the tube within the steam generator tubesheet. The third sleeve design spans degraded areas of the steam generator tube at tube support plates or in a free span section of the tube. This tube suoport sleeve is welded at both ends.

The revised TS would reference the current generic topical report for CE welded sleeves, CEN-629 P, Revision 02," Repair of Westinghouse Series 44 and 51 Steam Generator Tubes Using Leak Tight Sleeves," and CEN-629 P, Addendum 1, Revision 1, of the same title, both dated January 1997 [ proprietary information - not publicly available). Because the bulk of the technica!

i regulatory issues for the present request are identical to those reviewed in the previous i

/ evaluations (SEs) for CE sleeves, this SE discusses only those issues warranting 31sion, amplification, or inclusion based on recent experience.

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Details of prior _ staff evaluations of CE sleeves may also be found in the SEs for Waterford Steam Ele:tric Station, Unit 3, Docket No. 50-382, dated December 14,1995; Byron Nuclear Power Station, Units _1 and 2, and Braidwood Nuclear Power Station, Units 1 and 2, Docket

.Nos. 50-454,50-455,50-456, and 50-457, dated April 12,1996; Zion Nuclear Power Station, Units.1 and 2, Docket Nos. 50-295 and 50 304, dated October 29,1996; and Kewaunee t

Nuclear Power Plant, Docket No.- 50 305, dated June 7,1997. The staffs conclusiord in these evaluations apply to the proposed Prairie it!and license amendments unless superseded by an evaluation discussed herein.

2.0 BACKGROUNQ 2.1~ Summerv of Previous Reviews Previous staff evaluations of CE sleeves addressed the technical adequacy of the sleeves in the four principal areas of pressure-retaining component design: structural requirements,

! mateial of construction, welding, and nor destiuctive examination. The staff found the analyses and tests that were submitted to address these areas of comporent design to be acceptable.

The function of sleeves is to restore the structural and leakage integrity of the tube pressure i

. boundary. Consequentiv. structural analyses were performed for a variety of loadings including design pressure, operat,tg transients, and other parameters selected to envelop loads imposed during normal operating, upset, and accident conditions. Stress analyses of r,leeved tube assemblies wei performed in accordance with tne requirements of the American Society of Mec,anical Engineers (ASME) Boiler and Pressure Vessel Code, Section Ill. These analyses, along with the results of qualification testing and previous plant operating experience, were -

cited to demonstrate that the sleeved tube assembly is capable of restoring steam generator tube integrity.

The material of construction of the sleeves it nickel Alloy 690, a Code-approved material I

(ASME SB-163), covered by ASME Code Case N-20. The staff has found that the use of Alloy 690 thermally treated (TT) sleeves is an improvement over the Alloy 600 material used in the original steam generator tubing? Currosion tests conducted under Electric Power Research

-Institute (EPRI) sponsorship corifirm test results regarding the improved corrosion resit'ance of Alloy 690 TT over that of Alloy 600. The NRC staff has concluded as a result of these 2

laboratory corrosion tests that Alloy 690 meets the gu'idelines in Regulatory Guide 1.85,

" Materials Code Case Acceptability-ASME Section ill, Division 1" (Rev. 24, July 1986) and, therefore, is acceptable. The NRC staff has approved use of Alloy 690 TT tubing in replacement steam generators as well as sleeving applications.

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The welding process employed to join the sleeve to tile parent tube !s automatic autogenous GTAW (gas-tungsten arc welding)J The application of this process to the CE sleeve design was qualified and demonstrated d_uring laborotory tests employing full-scale sleeve / tube mock-ups.

Qualification of the welding procedures and welding enuipment operators was performed in accordance with the requirements of the ASME Code,Section IX (Welding).

4 The staff considers sleeves to be a longderm repair but not a repair with unlimited service life.

The installation of CE leak-tight meeves involves welding the sleeve to the tube which h

3-potentially creates new locations susceptible to stress-corrosion cracking. The time for the initiation of service-induceo degradation in sleeve / tube assemblies is not quantified. Operating experience with tubes fabricated from Alloy 600 indicates that initiation times can vary significantly depending on residual stresses, variability in material properties, and the chemical environment adjacent to the tube material. Consequently, although vendors traditionally conduct eccelerated corrosion tests of sleeve / tube assemblies for the purpose of making service life predictions the staff finds this method too unreliable for deterministic predictions.

However, the staff door consider the corrosion test results a good relative indicator of potential performance.

Considering the unreliability of sleeve lifa predictions, the staff has typically required licensees to inspect a sample of sleeves at each outage. Period:c inservice inspections will provide assurance that any service-induced degradation in sleeves is detected and addressed appropriately. Inservice inspection requirements applicable to the licensee's proposed amendment request are discussed further in Section 2.2.3 of this SE.

2.2 Discussion Recent experience with the installation and inspection of steam generator tube sleeves has highlighted several areas that were either not relevant to previous sleeving amendments or addressed in detailin the staff evaluations of the sleeving amendments previously referenced.

These issues include (1) the preparation of tube surfaces prior to sleeve welding, (2) the adequacy of inspection techniques used to accept sleeve welds, (3) inservice inspection requirements for sleeved tubes, (4) the omission of post-weld heat treatment (PWHT) for

.leeve welds, and (5) changes in the eddy current data acquisition rate from the original qualification. In addition to each of these topics, the licensee's proposal to establish a plugging limit for sleeve degradation is discussed in the following sections.

2.2.1 Weld Preparation

- in order to form an adequate sleeve to tube weld, prior to performing any weld, the surface of the metal (s) to be welded must be cleaned. For stoeve installat!on, the inner diameter of the parent tube at the desired weld location must be cleaned of service-induced oxides. The presence of impurities during the welding process can lead to the unacceptable wc!d indications. For the CE sleeving process, the tube inner surface is cleaned using motorized wire brushes.

Based on recent findings during the increction of sleeves at other niants, the industry has identified the cleaning process as an essential step in the sleeve installation process. This conclusion is based on an ABB/CE root cause assessment that concluded that changes in the cleaning process, implemented in prior sleeve installations, resulted in the formation of weld zone indications, in order to minimize the potential for these indications, the vendor enhanced the tube cleaning process to ensure the optimum removal of service-induced oxides prior to welding. In order to verify the removal of oxides, a 100-percent visual examination of the cleaned area is performed. CE recommends the visual ex.mination as an interim step until enough field experience is gained to consider adoption of a statistical sampling plan in the future. The licensee for Prairie Island will confirm the effectiveness of the cleaning step in the

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- 1 L sleeve installation by a visual examination of the tube inside diameter surface, as recommended by CE..The licensee will initially inspect 100 percent of the tubes to be sleeved

' prior to sleeve installation. However, if the visualinspections reveal that the cleaning process is effectively removing all tube oxide deposits, the licensee may relax the requirement to visually

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inspect tubes after cleaning.

2.2.2 Wold Acceptance' inspections To verify the acceptability of sleeve welds, the licensee will complete an initial exambation of sleeved steam generator tubes prior to retuming a repaired tube to service. The acceptance -

examination includes an inspection using visual ultrasonic, and oddy current techniquesc The analysis of inspection data from three diverse methods of inspection improves the ability to.

detect fabrication induced defects. In addition, edC current data are also used as a baseline for comparison with data obtained in future required periodic inspections.

- Past field experience has demonstrated that previous initial acceptance examinations based on

- visua' and ultrasonic inspect on tec n ques may not be sufficient to identify all fabrication-i hi induced defects. As a result, the weld acceptance nondestructive evaluation (NDE) was

- modified. The modifications include inspection using an ultrasonic tester with sn enhanced digitized amplitude system. The enhanced ultrasonic inspection technique provides a greater -

number of signel properties to mere fully characterize a weld. The modified procedure was

- extensiveiy tested on laboratory produced welds containing a variety of inclusion and lack of

-fusion defects. Sample 1 were destructively examined and the metallurgical sections compared with the inspection results. Comparison of results demonstrated the revised procedure was highly reliable and tha'. no significant defects should remain undetected when using the enhanced procedure.

o In addition to ultrasonic testing, the sleeve weld acceptance criteria require a 100-percent eddy current inspection using a plus point probe. Field experience led CE to discover that weld suckback and circumferentially oriented oxide inclusions would not be detected by ultrasonic inspection techniques.- CE has shown the plus point probe reliably detects the various fabrication-induced weld defects, including blowholes, weld suckback, and circumferentially i

oriented oxide inclusions. The vendor has also shown that eddy current methods can locate the position of a fabrication defect with respect to the weld centerline which is considered the -

4 pressure boundary. Thus, for an FDTS sleeve upper weld, indications located above the weld -

centerline that are acceptable with other inspection techniques may be left in service. However, any indication found below the weld centerline requires the tube to be plugged For the lower' welds on tube support sleeves, this criterion is appropriately rr.cdified so that indications below the weld centerline may be left in service.

- During a recent installation of welded sleeves at Kewaunee Nuclear Power Plant, the Kewaunee licensee visually identified weld zone indications that were not identified with either eddy current or ultrasonic inspection techniques. Therefore, this finding may indicate that all three inspect on methods are needed to ensure acceptable sleeve welding. The licensee for

- Prairie Island will perform a 100-percent visual examination of all sleeve welds in the fall 1w97 F

Prairie Island Unit i refueling outage. The licensee has indicated that visual inspections of a

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aleeve welds in other future outages may become optionalif a high degree of weld acceptability can be demonstrated.

2.2.3 Inservice Inspection Requirements

' nciudod in the licensee's proposed amendment request are changes that would require the i

e licensee to perform an inspection of a number of sleeves at each refueling outage. The minimum sample requirements for tube inspections, which are specified in " Steam Generator Sample Selection and inspection

• within TS 4.12, are established to assess the overall candition of the steam generator. Because slecyed tubes are of a slightly different configuration and may be more susceptible to stress-corrosion cracking than unrepaired tubing, the inservice inspection requirements currently specified in the TS may not be sufhcient to -

address the condition of these tubes.

r The licensee has prcposed to include additional inservice inspection requirements in the TS to address sleeves. The changes would require the inspectiun of at least 20 percent of all installed sleeves. This proposal is consistent with current industry guidance for steam generator sleeve examinations. EPRI recommends a 20-percent sample inspection for sleeves; in addition to this licensee proposal, the results from inspections would be classified and, depending on the classification, may require the performance of additionalinspections of

sleeves, j

2.2.4 Post Weld Heat Treatment One primary eleme,J in the development of service-induced stress-corrosion cracking in steam generator tubing is the residual stresses in the material. In unrepaired tubing, these stresses could originate from the original fabrication of the tubing or from deformation of the tube material at low temperatures (e.g., tubesheet expansion). The installation of sleeve welds will also introduce residual stresses from the weldmg process in both the sleeve and the tube.

These stresses have the potential for increasing the susceptibility of the welded materials to stress-corrosion cracking. - A PWHT can reduce these stresses thus potentially increasing the L

time for the initiation of crackirm within a welded joint.

. The licensee for Prairie Island has indicated that the PWHT of sleeve welds is optional to reduce stresses in the welds above the tubesheet. At this time, the licensee has indicated it intends to implement a PWHT for sleeve welds. However, this position will be evaluated at -

each outage that sleeves are installed. Although the omission of a PWHT step may reduce the potential service life of a repaired tube, operational experience with sleeve welds that have not received a PWHT has been good to-date. In addition, the relatively low hot leg operating temperature (590*F) of Prairie Island Units 1 and 2 minimize the potential for the initiation of stress-corrosion cracking.

2.2.5 Sleeve Plugging Limits The sleeve minimum acceptable wall thickness is determined using the criteria of Regulatory

- Guide (RG) 1,121, " Bases for Plugging Degraded PWR Steam Generator Tubes," and ASME Code Section til allowable stress values and pressure stress equations. According to RG 1.121 L

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i 6-criteria, an allowance for NDE uncertainty and postulated operational growth of tube wall

' degradation within the sleeve must be accounted for when using NDE to determine sleeve plugging limitsi Therefore, a conservative tube wall combined allowance for postulated

- degradation growth and oddy current uncertainty of 20-percent through-wall per cycle was assumed for the purpose of determining the sleeve plugging limit. The sleeve structural limit, which was calculated based on the most limiting of normal, upset, or faulted conditions for; 7/8-inch outside diameter steam generator tubes in Westinghouse Model 44 and 51 steam 4

_ generators, was determined to be 51 percent of the sleeve nominal wall thictoiess based on

' ASME Code minimum material properties in accordance with staff posi' ions. Removal of sleeved tubes from service when degradation in the sleeve pressure boundary reaches a depth of 31 percent provides assurance that the minimum acceptable wall thickness will not be violated during the next cycle'of operation.

2.2.6 Qualification of Eddy Current Inspection Techniques

- In the submittal dated October 3,1997, the licensee requested that the NRC incorporate CE Engineering Report 97-TR-FSW-001, Revision 0, " Sleeve Data Comparison for Motorized Rotating Plus Point Coil at Various Rotational and Axial Sample Speeds in 0.875[-inch) Tubing,"

into the review of the license amendment request to install CE welded sleeves. The referenced topical report provides qualification test results that demonstrate the ability to acquire eddy current inspection data at a higher rate than originally qualified in ABB/CE report 96-OSW-003-P, Revision O. The original qualification report is referenced in CE topical report CEN-629-P, Revision 1, and qualified a rotating probe pull speed of 0.1 inch per second. The licensee has proposed to inspect CE-welded sleeves for detection of sleeve indications at pull speeds greater than 0.1 inch per second, specifically 0,45 inch per second. In order to characterize the nature of any detected indications using eddy current methods, the licensee would acquire data using probe pull speeds consistent with the original qualification documented in 96-OSW-003-P, Revision 0 (0.1 inch per second).

3.0 EVALUATION The staff concludes the proposed sleeving repairs as described in the topical report,

' Combustion Engineering Leak Tight Sleeves" (CEN-629-P), can be accomplished to produce sleeved tubes of acceptable metallurgical properties, corrosion resistance, and structural and leakage integrity. As indicated previously, recent experience has indicated the need to evaluate additional areas that were either not relevant to previous CE sleeving amendments or l addressed in detail in previously approved CE sleeving amendments. The staff evaluation of these issues is discussed below.

Visual surface examinations of the tube inside diameter surface will be used to confirm the adequacy of the cleaning process. The licensee indicated in its amendment that this requirement may be relaxed if the cleaning process appears to be effective. The use of the visual examination will enable the vendor to detect inadequately cleaned surfaces prior to sleeve installation and welding. Welding the sleeve to a poorly cleaned tube surface may result in weld zone indications and possible rejection of the sleeve weld. Experience has-

demonstrated that the indications that arise from inadequate cleaning are detectable using eddy current and ultrasonic inspection methods. Should the licensee elect to eliminate the visual A.:.

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structural and leakage integrity) of the sleeve weld will eventually be assessed through post-weld examinations. Because the visual inspection of cleaned tube surfaces does not affect the final disposition of sleeve welds, the staff concludes that td licensee's proposal to make these inspections optional is acceptable.

The licensee's proposal to delete the optional visual inspection of sleeve welds depends on its ability to demonstrate that the visual examination does not detect fabrication indications that are

-- detrimental to the structural and leakage integrity of sleeved tubes. The decision to implement visual examination requirements stems from one instance at another plant where indications were identified only by visual inspection methods. At this time, experience with these indications is limited. Consequently, the licensee will assess the need to continue visual examinations based on experience gained in the upcoming refueling outage. The NRC staff agrees that, given the limited experience with_ visual sleeve weld acceptance examinations, the performance of visual inspections may not be necessary once additional data from this method of inspection become available. Therefore, the staff concludes that the licensee's proposal to optionally inspect sleeve welds with visual examination techniques is acceptable.

The Prairie Island stearn generator tube surveillance requirements cunently require an examination of at least 3 percent of the inservice steam generator tubes. The proposed

- requirement to :nspect a 20-percent sample of sleeves at each refueling outage mandates additional inspection sampling that specifically addresses the potential for degradation in repaired steam generator tubing. Because the proposed scope for the inservice inspection of sleeves increases the probability that sleeve / tube degradation is identified during the course of inspections, the staff finds the licensee's proposal for the sleeve inservice inspection requirements acceptable.

A PWHT of sleeve welds may reduce the residual stresses in the vicinity of the sleeve / tube weld and thus decrease the susceptibility of the assembly to stress-corrosion cracking.

However, the staff recognizes that, based on previous operating experience, sleeve welds installed without the benefit of a PWHT have demonstrated considerable resistance to stress-corrosion cracking. In addition, the staff notes that sleeve welds should have adequate resistance to the development of service-induced degradation so as to prevent the initiation and growth of flaws that could challenge the structural and leakage integrity of repaired tubes dering an operating cycle. If cracking develops within sleeve welds in the future, the requirement to inspect a 20-percent sample of sleeved tubes will improve the likelihood that degraded sleeves are identified and dispositioned according to the TS Repair Limit.

L CE Report 97-TR-FSW-001, Revision 0, documented the qualification of eddy current probe l-pull speeds up to 0.6 inch per second. The staff previously reviewed a proposal from Wisconsin Public Service Corporation (WPSC) to use higher eddy current probe speeds in the l

- inspection of CE-welded sleeves at Kewaunee referencing this same qualification report. The NRC approved a maximum pull speed of 0.45 inch per second for the inspections at Kewaunee.

Based on the results of the performance demonstration documented in 97-TR-FSW-001, Revision 0,' the NRC concluded that this pull speed was acceptable for dctection only. Data

' obtained to characterize the nature of indications with eddy current were to be acquired at a pull speed of 0.1 inch per second. Because the proposal by the licensee to inspect sleeves at L

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Preio Island is consister, a the inspection parameters previously reviewed for sleeve inspections at Kewaunee, the staff concludes that the use of an elevated data acquisition rate

- of 0.45 inch per second is acceptable for the detection of sleeve indications with oddy current.

inspection methods, if the licensee should desire to utilize probe pull spoods in excess of 0.45 and 0.1 inch per second for detection and characterization, respectively, a roqualification would l

be necessary to demonstrate equivalent or improved inspection capabilities at the higher speeds.

The structural analysis of sleeve / tube assemblies in CEN-629-P, Revision 02, assumes a material ultimate tensile strength of 90 kai for Alloy 690 sleeves. According to the topical report, this value was determined based on actual test data. The sleeve design description in the report specifies that the Alloy 690 tubing 'is procured to the requirements of the ASME Boiler 4

and Pressure Vessel Code, Section 11 SB-163, Code Case N 20." In addition, Section 2 of the topical report states that the sleeve dimensions, materials, and joints were designed to the applicaole ASME Boiler and Pressure Vessel Code. The staff notes that ASME Code Case N-20-3 states, " nickel-chromium-iron Alloys 600 and 690...may be used in the construction of Class 1 components in accordance with Section Ill, Division 1, provided the tensile, yield -

strength, and design stress intensity values as listed in Tables 1,2, and 4, respectively are used." Table 1 in Code Case N 3 lists the ultimate strength of Alloy 600 and 690 as 80 ksi.

Therefore, the staff has coaciuded that the use of 90 kaiin the calculations to evaluate sleeve margins of safety is inconsistent with the design requirements stated in CEN-629-P, Revision 2.

The staff notes that the use of a 90-ksi tensile strength does not afioct the conclusion that the sleeve design will provide adequate structural and leakage integrity for repaired steam generstor tubes, in addition, the proposed slesve repair limit is also unaffected by the use of an incorrect value for material tensile strength.

The licensee has proposed to amend the Prairie Island Unit 1 and 2 TS to permit the installation of CE leak tight sleeves per topical report CEN-629-P, Revision 2 and CEN-629-P, Addendum 1, Rev.1. Other requirements as specified previously are also proposed for the installation and inspection of welded sleeves. The NRC staff has concluded, based on previous evaluations of CE sleeve reoairs and the discussion included Section 3.0 of this SE, that the L

amendments to the Prairie lwand TS to allow the installation of CE sleeves are acceptable and

. will ensure that steam generator tube integrity is maintained. Although some of the calculations in the referenced topica! report are in error due to the use of invalid material properties, the staff notes that the overall results obtained from the analysis are correct. Therefore, the conclutilon of acceptability of the proposed TS changes remains unchanged.

4.0 Summary The NRC staff concludes that the proposed sleeving repairs, as described in the CE sleeve topical reports CEN-629-P, Rev. 2 and CEN-620-P, Add.1, Rev.1 will produce sleeved tubes with acceptable metallurgical properties, structural and leakage integrity, and corrosion resistance. Therefore, the NRC staff concludes that the repair of SG tubes using sleeves designed by CE and described in the aforementioned topical reports is acceptable.

= The licensee proposed the following changes in the TSs to implement the CE sleeving repair methodologies discussed above:

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1. Proposed Changes to TS 4.12.B, " Steam Generator Tube Sarnple Selection and inspection"

- A new requirement is added to specify that a minimum sample inspection of 20 percent of the total number of sleeves in service in both steam generators is required. In addition, the results of the sleeve inspections are to be classified and addttional actions taken, if -

necessary, per Table TS 4.12-2.

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2. Proposed Changes to TS 4.12.B.4, " Steam Generator Tube Sample Selection and Inspection' This section is modified to require additional Inspections of sleeved tubes based on the re'sults classification of the initial sample inspection.

3. Proposed Changes to TS 4.12.D.1(f), ' Repair Limit" The definition of Repair Limit is modified to specify that the repair limit for the pressure boundary region of any sleeve is 31 percent of the nominal sleeve wall thickness.

4. Proposed Changes to TS 4.i2.D.1(i), " Sleeving" The definition of Sleeving is modified to permit tube repair by,nserting Alloy 690 sleeves inside the parent tube over degraded tube areas and securing the sleeve in place by welding or mechanically rolling. The new sleeve then becomes the pressure boundary.

S. Proposed New TS 4.4.12.D.3 Section is added to specify that tube repair using CE-welded sleeves shall ise in accordance with the methods described in CE topical reports CEN-629-P, Revision 2, and CEN-629-P,

. Addendum 1, Revision 1.

6. Proposed New Table TS 4.12-2, ' Steam Generator Tube Sleeve inspection" Table TS 4.12-2 is added to the TS to specify that a 20-percent sample inspection is required for tube sleaves, in addition, the table also states the actions (i.e., additional inspections) necessary based on the results classification from the initial sample.

7. ~ Proposed Changes to B 4.12, " Bases

• The bases for including additional inservice inspection requirements for sleeved tubes is added, in addition, the section is modified to indicate that the NRC has approved the installation of CE le.k tight sleeves per CEN-629-P for sleeves installed after January 1, 1997.

- The staff has reviewed the TS changes discussed above and finds that they consistently incorporate the CE sleeving repair processes previously discussed in this SE and will provide adequate assurance of SG tube integrity. Therefore, the proposed changes are acceptable.

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5.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Minnesota State official was notified of the ptaposed issuance of the amendments.1The Sti.e official had no comments.

6.0 ENVIRONMENTAL CONSIDERATION

- The amendments change a requirement with respect to installation or use of a facility component located within the restric'ad area as defined in 10 CFR Part 20 and change.

surveillance requirements. The NRC staff has determined that the amendments involve no significant increase in the smounts, and no significant change in the types, of any effluents that may oe 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 amendments involve no significant hazards consideration and there has been no public -

comment on such finding (62 FR 43370). Accordingly, the amendments meet 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 amendments.

7.0 CONCLUSION

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 j

Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: P. Rush Date: November 4, 1997 l

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