ML18058A978

Responds to NRC Re Violations Noted in Safety Insp Rept 50-255/92-12.Corrective Actions:All Longitudinal Welds on Main Steam Sys Requiring Insp,Examined by Volumetric & Surface Methods

ML18058A978
Person / Time
Site:	Palisades
Issue date:	07/22/1992
From:	Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9207290163
Download: ML18058A978 (18)

Text

...

consumers Power

~-91' PDWERINli NllCHlliAN'S PRDliRESS Palisades Nuclear Plant:

27780 Blue Star Memorial Highway, Covert, Ml 49043 July 22, 1992 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

GB Slade General Manager REPLY TO NOTICE OF VIOLATION - NRC INSPECTION REPORT No. 92012 - INSERVICE INSPECTION AND VENTILATED CONCRETE CASK TEMPORARY FUEL STORAGE FACILITIES NRC Inspection Report No. 92012, dated June 22, 1992, forwarded the results of an NRC inspection of the ventilated concrete cask (VCC) temporary fuel storage facilities at Palisades, and the results of a special safety inspection conducted by the NRC Region I Nondestructive Examination mobile team.

The inspection report identified two apparent violations of NRC requirements and eight unresolved items in the Inservice Inspection (ISI) area and one unresolved item concerning the VCC.

Our reply to the Notice of Violation is provided in Attachment 1 to this letter. The replies to the unresolved items from the ISI inspection are provided in Attachment 2, and the reply to the unresolved item identified during the VCC inspection is provided in.

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Gerald B Slade O General Manager CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachments

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CONSUMERS POWER COMPANY To the best of my knowledge, information and belief, the contents of this submittal are truthful and complete.

P Hoffman, Vi e Nuclear Operat1 Sworn and subscribed to before me this.>/#it'"day of ~ 1992.

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ATTACHMENT 1 Consumers Power Company Palisades Plant Docket 50-255 REPLY TO NOTICE OF VIOLATION NRC INSPECTION REPORT No. 92012 - ISi July 21, 1992 3 Pages

REPLY TO NOTICE OF VIOLATION Violation 1 10 CFR, Part 50.55a, requires, in part, that inservice inspection (ISI) of plant components be conducted in accordance with the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (Code),Section XI.

Section XI of the Code requires that longitudinal pipe welds be included in the ISI program and inspected at the intersection with circumferential pipe welds.

Contrary to the above, as of March 30, 1992, longitudinal pipe welds which intersect circumferential pipe welds MSS-36-MSL-lSl-211, MSS-36-MSL-2Sl-212 and MSS-36-MSL-2Sl-219 on the main steam system were not included in the licensee's ISI program and had not been inspected (50-255/92012-10).

Reason for the Violation 1

The root cause of this violation was personnel error in that the main steam system longitudinal welds were inadvertently left out of the ISI database when the database was developed. This issue was previouslj addressed in licensee event report (LER)92-025, dated April 29, 1992.

Corrective Actions and Results Achieved The corrective actions for this violation are addressed in LER 92-025.

All the longitudinal welds (30 total) on the main steam system that required inspection were examined by volumetric and surface methods prior to the plant leaving cold shutdown from the 1992 refueling outage. All welds were found to be satisfactory.

In addition, all longitudinal welds on the main steam system have been added to the ISI 40 Year Master Plan.

Corrective Action to Avoid Future Non-Compliance The corrective actions taken, as outlined in LER 92-025 are considered adequate to prevent this condition from re-occurring and, therefore, no further corrective action is required as a result of this violation.

Date of Full Compliance Full compliance has been achieved.

Violation 2 10 CFR, Part 50, Appendix 8, Criterion XVII, requires, in part, that inspection records include, as a minimum, the results, the acceptability, and action taken resulting from any deficiencies noted.

Contrary to the above, as of March 25, 1992, the inspection record for weld ESS-12-SIS-281 did not include the results and acceptability of the examination in that the inspection record failed to identify that the Code required inspection volume was not examined in full (50-255/92012-07).

Reason for the Violation ASME Section XI, Mandatory Appendix Article 111-4430 requires that when performing ultrasonic examinations the weld be scanned in two directions with an angle beam transducer to identify reflectors transverse to the weld seam.

2 During the performance of the weld examination on weld ESS-12-SIS-281-1 the 45° transverse scan could not be performed due to the weld crown being in an as welded configuration (i.e., the weld surface was too rough for the transducer to ride smoothly over the weld without loss of transducer contact to the metal surface.) However, when the CPCo NDE examiner completed the data sheet for this examination he failed to document this limitation for the 45° transverse scan.

When the NRC Mobile Laboratory technicians attempted to repeat the CPCo examination, they identified that the 45° transverse scan of this weld was limited and the required volume for examination could not be achieved.

As a result of this NRC finding, CPCo's NDE technicians calculated that only 14% of the required 100% volume was examined in the transverse direction, based on the transducer that was used for the examination.

The ultrasonic examination procedure used for the examination required that when performing angle beam examinations the NDE examiner list access limitations on the data sheet.

The NDE examiner listed two limitations on the data sheet when the exam was performed; however, the NDE examiner failed to list the limitation for the 45° transverse scan.

This was a failure to document a limitation as required by the procedure.

Additionally, Inservice Inspection personnel failed to identify the limited examination and that the weld examination was incomplete.

Another factor which led to this violation was that the data sheets which were used in this procedure only required that the NDE examiner list the starting point and ending point of the required scan path.

Limitations to the required scan path could not be easily documented within the data sheet.

The data sheets were also in error in that the surface from which examination is conducted was not clearly established on the data sheet.

Corrective Actions and Results Achieved ASME Section XI credit was not taken for weld ESS-12-SIS-281-1.

A weld count was completed to insure that period requirements of ASME Section XI, Table IWC-2412, Inspection Program 8, were satisfied.

Corrective Action to Avoid Future Non-Compliance 3

1.

The ultrasonic procedures will be revised to strictly require that limitations be documented.

Also, the data sheets, which are an attachment to the ultrasonic procedures, will be revised so that limitations can be easily documented and that the surface from which examination is conducted is clearly *identified.

2.

A review of all completed ultrasonic data sheets from the present Inservice Inspection interval will be performed to identify if any other data sheets may exist where a limitation did not allow a complete examination.

If any data sheets are identified, these examinations will be re-performed during the 1993 refueling outage.

3. All NDE technicians who perform ultrasonic examinations will be re-indoctrinated to the revised ultrasonic procedures to insure that their understanding of the procedures is satisfactory.

4.

Examination of weld ESS-12-SIS-281-1 will be added to the Inservice Inspection scope of examinations for the 1993 refueling outage. This weld will be ground so that the required volume of examination may be satisfied.

Date of Full Compliance Full compliance has been achieved.

ATTACHMENT 2 Consumers Power Company Palisades Plant Docket 50-255 REPLY TO UNRESOLVED ITEMS NRC INSPECTION REPORT No. 92012 - ISI July 21, 1992 Pages

1 Unresolved Item 92012-01 NDE Procedures Before a license's program of inspection is used, it must be approved by the Nuclear Regulatory Commission under the authority embodied in 10 CFR 50.55a (g) (4) (iv).

The required inspections are detailed in the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI for Inservice Inspection as embraced in 10 CFR 50.55a (b).

For any inspection program, the code edition and addenda used is determined in accordance with the requirements of 10 CFR 50.55a (g).

For Palisades Power Station the applicable code edition is 1983 with the Summer of 1983 addenda (a.k.a.,

83S83).

It was found during this inspection that the following procedures had been revised to comply with the 1983 Edition with Winter of 1984 Addenda (a.k.a.,83W84) edition of the ASME code even though this edition was not approved for use at the plant by the NRG: NDT-PT-01, Rev 9; NDT-PT-02, Rev 5; NDT-RT-01, Rev 8; NDT-MT-01, Rev 7; NDT-UT-02, Rev 4; NDT-UT-08, Rev 2.

These procedures were revised in this manner in order to be able to use them uniformly through out the Consumers Power system; both at Big Rock Nuclear Power Station, Palisades Power Station in addition to their fossil fueled plants.

No evidence was available showing that a technical review of the procedures had been undertaken to determine if the revision impacted any technical specification or quality commitment at the plant. This is unresolved (50-255/92012-01) pending the licensees review.

Palisades Position We agree that at the time of the revision of the NDE procedures, no technical review was documented.

However, in the procedure review process we believe we adequately reviewed the requirements of both the 1983 Edition of the code through the summer 1983 Addenda (83S83) and the 1983 Edition through the 1984 Winter Addenda (83W84) and ensured no 83S83 requirements were deleted in conducting the required specifications.

Since the time when this unresolved item was identified, a second technical review of the NDE procedures has been completed and documented.

Our review concluded that no technical specification or quality commitments were impacted.

For further clarification, all procedures are being revised to be site specific and to state th'at they are written to satisfy the ASME Boiler and Pressure Vessel Code 1983 Edition with the Summer 1983 Addenda.

Unresolved Item 92012-02 NDE Procedures Paragraph IWA 2120 and Mandatory Appendix III, Paragraph 2300 (p) requires the approval of the ANI for a71 NDE procedures.

This requirement for approval includes, in the former paragraph, the requirement that each procedure "sha71

2 include, as a m7n1mum, the following information:... (p) approval of the procedure as required by IWA 2120." This requires some form of testimony on the procedure, that the ANI has approved the procedure.

The simplest way of fulfilling this obligation is by having the ANI sign off the procedure as a matter of course.

Palisades had no such testimony on the procedures.

The only proof that the ANI was involved in the process was a sheet with his signature listing a number of instances where each procedure had been used during an actual inspection.

These inspections were dated approximately 1~ to 5 months after the procedure was issued. Although the code does not state specifically that the procedure must be approved by the ANI before use, the method submitted by Palisades does not preclude the use of the procedure for 5 months without ANI approval.

Had the ANI disapproved the procedure it would fall to Palisades to prove that the procedure had not been used in the interim or, failing that, reinspect all the items that had been inspected in the interim.

Pending the licensees revision of the procedure to make them plant specific, this will remain an unresolved finding (50-233/92012-02).

Palisades Position ASME Section XI, IWA 2120(d) requires that the Authorized Nuclear Inspector (ANI) verify that the NOE procedures meet the techniques specified in Section XI.

Palisades does not believe that ASME Section XI, IWA 2120, specifically requires that the ANI approve the NOE procedures prior to their use.

Palisades does believe it is prudent to document the verification that the NOE procedures are adequate prior to their use, and that appropriate actions will be taken.

In the future, to provide documented verification of procedure review, Palisades Administrative Procedure 10.42, "Procedure/Document Matrix," will be revised to require that the ANI review all NOE procedures used at the Palisades Nuclear Plant. This will insure that the ANI review of the procedures is performed before the procedures are used at Palisades.

Unresolved Item 92012-03 NDE Procedures The radiographic procedure at Palisades (NDT-RT-01, Revision 8) listed a table in paragraph 10.6.3.1 for double wall radiography.

This procedure, as noted earlier, was revised to the Winter '84 Addenda to Section XI.

The table of paragraph 10.6.3.1, is a reflection of an earlier edition of ASME Section V, Article 2.

The code has since dropped the table.

It is no longer applicable to Section V (referred to by Section XI for radiography) either for the Summer

'83 or Winter '84 Edition of the code.

According to the licensee the table remained since the procedure was used in a fossil plant where it was still applicable under ANSI 831.1 for power piping.

The table did not conform to the current requirements of ASME Section XI and Section V, since it required the use of a 25 penetrameter at 2T sensitivity for the thickness range of 1 to and including 1~ inches and the code requires that a 20 penetrameter at 4T

sensitivity be used in the range of 1 to and including 1% inches.

The licensee was unable to give a satisfactory technical justification for this deviation from the code and it remains as an unresolved item (50-255/92012-03}.

Palisades Position 3

We agree that in radiography procedure NDT-RT-01 Revision 8, Section 10.6.3, "Penetrameter Selection," the double wall radiographic technique identified is not addressed in the Winter 1984 Addenda of the 1983 Edition ASME Section V, Article 2; however, we do not agree that the table listed in paragraph 10.6.3.1 is no longer applicable to Palisades.

The penetrameter selection for double wall radiographic technique "Table T-272" of ASME Section V, Article 2, 1983 Edition, was not deleted until the Summer 1984 Addenda and is, therefore, applicable to the Palisades Plant.

Based on Table T-272 of ASME Section V, Article 2 being applicable to ASME Section XI, 1983 Edition Summer 1983 Addenda, it was determined that it would remain in procedure NDT-RT-01, Revision 8 due to the technical aspects of meeting code requirements and its applicability to Palisades. Also, as identified in the table of paragraph 10.6.3.1 of procedure NDT-RT-01, Revision 8 the penetrameter selection for double wall radiographic technique is 25 at 2T sensitivity for a material thickness range of over 1.00 through 1.50 inches. Additionally, when taking into account penetrameter equivalence, a number 25 penetrameter at a 2T sensitivity is 0.005% more sensitive than a number 20 penetrameter at 4T sensitivity.

With respect to the licensee making a statement that the table remained in the procedure because the procedure was being used at fossil plants (where Table 10.6.3.l was still applicable) was a misunderstanding. Although the procedure is used at facilities other than Palisades, the penetrameter selection for fossil activities is based on the 1989 ASME Code,Section VIII, and is Attachment "F" in procedure NDT-RT-01, Revision 8.

As a result of the reviews conducted in the development of the response to this unresolved item, the NDE procedures will be revised to be site specific procedures, using the 1983 Edition with the Summer 1983 Addenda.

Unresolved Item 92012-04 ISI Program It is the intent of ASME in formulating the requirements of Section XI for an inservice inspection program to track indications for trends; as well as detect them.

This is reflected in ASME Section XI, Paragraph IWB 3131 (for class 1 and 3 piping) and Paragraph IWC 3131 (for class 2 welds). Detailed in these references is the stipulation to compare the current state of an indication with its previous state. Volumetric and surface examination results "shall be compared with recorded results of the preservice examination and prior inservice examinations." This is further strengthened in IWB 3131.1

4 and IWC 3131.1 when it states that if the "volumetric or surface examination either reconfirms the absence of flaw indications or reveals flaw indications that do not exceed the acceptance standards listed... "the component sha77 be deemed acceptable for continued service. Palisades was not doing this analysis for a77 indications; just those that were rejected. This makes Palisades far Jess able to trend indications in the plant and develop an early warning system for any generic category of indication. This is an unresolved finding pending the licensees review of reports (50-255/92012-04).

Palisades Position We agree that the results of all recorded examinations shall be compared to previous examination results and that Palisades was only comparing rejectable indications to previous recorded results. This past practice did not satisfy the intent of the code.

Therefore, the results of the examinations that were completed during the 1992 refueling outage were compared to previous examinations and the results were determined to be acceptable.

To assure that the requirements of Section XI, Paragraphs IWB-3131 and IWC-3131 are met, a review of all previously completed data sheets from this inspection interval will be performed. Also, the Palisades Inservice Inspection Outage Plan will be revised to develop an administrative method for comparing and documenting these required reviews.

Unresolved Item 92012-05 ISI Program The licensee has a written system that identifies a method of orientation for the recording of indications on the final reports as required in ASME Section XI, Paragraph IWA-2610, and this system meets the intent of the requirement.

However, the identification system does not include any requirement to permanently mark the weld centerline. This is an important basis for repeatability of the NDE and is further required in mandatory appendix Ill, paragraph III 4320.

It is important enough for the code to dedicate a full page supplement to appendix III describing suggested ways of accomplishing the marking system.

The licensee has centerline marked welds as part of modifications in safety systems but does not mark existing welds.

Pending the licensees evaluation of a method for conclusively determining the centerline of existing welds this will remain an unresolved item (50-255/92012-05).

Palisades Position.

As identified above, Palisades does use a written reference system which meets the intent of ASME Section XI, Paragraph IWA-2610.

Use of this reference system has been a requirement within each NDE method procedure.

5 The NDE procedures are currently being revised to strengthen the reference system, and part of this revision will be to remove the weld reference system from the NDE procedures and replace it with a new procedure that is similar to the example reference system provided in ASME Section XI, Appendix III, Supplement 2.

With respect to determining the method for marking the centerline of existing welds, ASME Section XI, Mandatory Appendix III, Article III-4320 states

"... Low stress stamps or vibratooling, or both, may be used to permanently identify each weld." This article does not mandate that a weld be stamped to identify the zero reference point. Article III-4330 states in part that

"... Circumferential and longitudinal welds requiring volumetric examination shall be marked once before or during the pre-service examination to establish a reference point." This was not a requirement during the Palisades pre-service examinations.

Palisades has begun a marking system for the pre-service inspection of newly created welds that require volumetric inspection; however, Palisades is not planning on permanently marking existing welds due to the fact that the weld crowns are easily visible and the NDE technicians can quickly locate the weld centerlines.

Palisades believes that the NDE examinations on existing welds are repeatable without marking weld centerlines. With the zero reference system provided in the new general procedure, Palisades is confident that repeatable examinations can be achieved and that no benefit will be realized by marking the centerlines of the existing welds in comparison with dose received to mark all existing welds.

Unresolved Item 92012-06 ISI Data Review The NDE evaluation of weld flaws, for acceptance, under Section XI is based on the stress of the indication in a plane. If two flaws are located sufficiently close to each other they are considered to be one flaw.

This evaluation is required in Paragraph IWA 3300 as diagramed in Figure IWA 3330-1.

The final Palisades ISI penetrant report for weld ESS-12-SIS-281-1 noted two, with the assumption that round penetrant indications are as deep a 1/2 their diameter.

This is also an unresolved finding pending the licensees revision of the report form and/or penetrant procedure to include the requirement to determine flaw separation (50-255/92012-06).

Palisades Position We agree that if two flaws are located sufficiently close to each other they are considered one flaw.

As a result of the evaluation of this unresolved item the following actions have been taken or are planned:

1.

Weld number ESS-12-SIS-281-1 was re-examined in the area where the indications at the same location were noted and it was verified that they could be classified as individual indications.

6

2.

Consumers Power Company NDE procedures and Inservice Inspection Specification will be revised to reflect the ASME Section XI, IWA-3000 requirements.

Unresolved Item 92012-08 ISI Performance An 80% of DAG reflector (intermittent in length) was not recorded for weld FWS-18-FWL-251-243 per the requirements of ASME Section XI, paragraph IWA-2232{b}, GP Procedure NDT-UT-01 Rev 8, paragraph 11.1 and ISI plan Rev 3, Appendix 6A, Parts B and E.

The licensee was unable to duplicate the NRG's results in this regard.

The equipment used by the licensee and the NRG was essentially the same and the transducer was the same type, brand, size and frequency from the same manufacturer.

The NRG Mobile NDE Laboratory subjected the two transducers to a frequency spectrum analysis.

The NRG transducer displayed an evenly changing bell curve that contained no lobes, while the licensee transducer showed side lobes.

The spectrum displayed clearly showed that the damping material in the licensee transducer has loosened to such a degree as to create ringing.

This ringing leads to a reduction of sensitivity of the transducer and explains why the licensee was unable to duplicate the results of the NRG.

The spectrum analysis performed by the NRG is available on the instrument used.by the licensee.

The NRG considers this another unresolved item since the licensee needs to dispose of the indication in the above weld and determine what other transducers might be in inventory that suffer from the same deterioration.

{50-255/92012-08).

Palisades Position During the examination of weld FWS-18-FWL-2Sl-243 CPCo's NDE technicians also noted an intermittent geometrical indication; however, the indication was below 50% full screen height on the Distance Amplitude Correction (DAC) Curve and was not required to be recorded on the data sheet for the examination.

During the system calibration on the plant calibration block, the performance parameters of the flaw detection unit along with the search unit for a particular examination are verified. Also, when establishing the DAC curve the search unit is directed toward the calibration reflector in the plant calibration block that yields the maximum response.

The reference gain of the flaw detection unit is then adjusted to bring that signal to 80% of full screen height.

By adjusting this reference gain the variations in performance characteristics between search units are compensated for.

The search unit in question (KBA 2.25mhz x 0.5 inch diameter) serial number 43920, which was used to examine weld FWS-18-FWL-2Sl-243, was sent back to the manufacturer (Krautkramer Branson) for analysis.

The analysis showed that the performance parameters for this search unit are acceptable.

Based on the performance characteristics being verified during calibration, and calibration

_J

7 verifications, and the acceptability of the manufacturers analysis, we have no reason to suspect that the search unit suffers from a loss of sensitivity and that the search unit would not have detected a recordable indication.

To explain the difference in the size of the indication which CPCo saw and the indication which the NRC recorded, it is possible that the differences in the equipment used and/or the use of different gain settings may have attributed to the different examination results.

We do not believe that the transducer which was used suffers from a loss of sensitivity; however, we will review previous radiographs to confirm that the indication is due to geometry and not a fl aw.

To address the question of other transducers that are in CPCo's inventory that potentially suffer deterioration, CPCo will also have these transducers performance parameters re-verified in an attempt to identify any transducer which may suffer from a loss of sensitivity. Based on these results, we will either continue to use the subject transducers or replace them.

In any case they will not be used at Palisades until their performance parameters are verified.

Regarding the NRC comment "... The spectrum analysis performed by the NRC is available on the instrument used by the licensee...," it is true that the instruments which CPCo uses are capable of performing the spectrum analysis; however, CPCo has not purchased the software to accomplish this task.

Before the next refueling outage CPCo will evaluate upgrading the equipment which we use to perform non-destructive examinations.

Unresolved Item 92012-09 ISI Performance Consumers Power procedure NDT-UT-01 Rev 8, para 7.2.2.2 D. states: "Search unit size, frequency, and angle shall generally be selected according to Table 1." Table 1 for a nominal material thickness of 1.00" to 1.5" lists a transducer size of 3/8" to 1/2" in size at an angle of 45° or 60°.

The thicknesses listed on the final ultrasonic examination reports for welds MSS-36-MSL-251-219, MSS-36-MSL-251-217 and MSS-36-MSL-251-218, are less than 1.5".

According to the Consumers Power procedure a 1/2" or less transducer would have been used.

There are no weld, geometry or interference restrictions which would have caused any other choice of transducer.

However, the welds were examined with a l" diameter transducer.

The large 45° shoe of this transducer (2 1/8" long by 1 11/16" wide) along with the wide crown of the minimally prepared surface of the weld meant that the required coverage of the 1/3 zone could not be obtained on the first 1/2 node.

Instead of exercising the options contained in ASME Section XI Para III-3230 (a) (1) and/or (2) along with Consumers Power procedure NDT-UT-01, Rev 8, para 7.2.3 A. and/or 8., which would have guided them back to the smaller transducer of their Table 1, they decided to extend the scan to a full 1 and 1/2 nodes in order to obtain coverage.

This means a sound path that is 3 times longer than a smaller transducer with the inherent loss of sensitivity to small indications.

8 The NRG examined weld 219 with a 1/2n diameter transducer using the first 1/2 node.

This examination revealed an indication that is 25n long and up to 100%

of the reference level.

The nature of the indication seems to be geometric but would require further examination to more fully categorize. Consumers Power was made aware of this discovery and repeated the examination with the in transducer and the transducer that was later determined by the NRG to suffer from a loss of sensitivity. This remains an unresolved item pending further evaluation by the licensee (50-255/92012-09).

Palisades Position We agree that the NOE technician's choice to use a I-inch diameter transducer instead of a I/2-inch or smaller transducer, which the procedure seemed to require, was not prudent; however, ASME Section XI does not specify the size of the search unit required to perform ultrasonic examinations.

In response to the NRC's question on the 26-inch long indication, weld 2I9 on line MSS-36-MSL-2SI was re-examined by CPCo's NOE group. This re-examination, performed with a 60° wedge, re-confirmed the geometric condition that was originally seen by CPCo's NOE technicians.

The indication was not recorded during the first examination due to the fact that the indication was found to be smaller than 50% full screen height on the Distance Amplitude Correction (DAC) Curve.

A review of previous radiographs, and the visual misalignment on the outside diameter of the pipe confirms the internal geometrical indications that were observed during the examination.

To ensure that the search unit used in the examination did not suffer from deterioration, the search unit (KBA 2.25 mhz x 0.5-inch diameter) serial number 43920, was sent to Krautkramer Branson for analysis and was found to be working properly.

We acknowledge that the NOE program at Palisades is in need of upgrading.

The ultrasonic procedures used at Palisades will be revised to upgrade the quality and detail of the examinations performed.

The revised procedures will not allow the use of I-inch diameter transducers and will require that the NOE technicians use the transducers specified in the body of the procedure.

We are confident that with the procedure revisions and equipment enhancements improved results will be forthcoming.

ATTACHMENT 3 Consumers Power Company Pali sades Pl ant Docket 50-255 DISCUSSION OF OPEN ITEM VENTILATED CONCRETE CASK FUEL STORAGE INSPECTION July 21, 1992 2 Pages

1 Unresolved Item 92012-11 Ventilated Concrete Cask for Dry Fuel Storage In summary, contractor oversight and QA/QC implementation was weak.

Examples of weaknesses identified during this inspection include failure to follow procedures, insufficient training of craft, and inadequate definition of QA/QC responsibilities. These weaknesses are collectively considered an unresolved item and a written response describing the licensee's evaluation of the extent of the problems and corrective actions taken is requested.

Palisades Position This unresolved item involves-observed weaknesses in CPCo's oversight of Pacific Sierra Nuclear's (PSN) work activities and QA/QC implementation during Ventilated Concrete Cask (VCC) fabrication at the Palisades Plant site. These weaknesses or inadequacies resulted from the unusual circumstance that, although CPCo was purchasing the VCCs from PSN as a finished product, PSN was fabricating the VCCs at the Palisades Plant site.

Although the PSN QA program stated that CPCo is responsible for on-site inspection of concrete work performed by PSN, to provide better continuity for the project, CPCo's Project Management and PSN's Project Management had agreed that PSN would perform on-site inspection of the VCC fabrication; however, no revision to the PSN QA program was made to reflect this change in responsibilities until after the first four casks were fabricated. This situation was further complicated during the concrete pour for cask No. 4 when CPCo agreed to perform the QC activities for that pour to alleviate PSN scheduling conflicts.

Any weaknesses or inadequacies in CPCo's oversight of PSN's work activities or implementation of their QA/QC program and any possibility of misunderstanding as to who is responsible for QA/QC during PSN's VCC fabrication at the Palisades site have been eliminated by:

1.

Revising the PSN QC/QC plan to state that PSN is responsible for all QC activities during VCC fabrication;

2.

Implementing CPCo vendor source verifications during PSN's cask fabrication at the Palisades site; and

3.

Increasing the detail of review performed by CPCo on PSN documentation.

. I 2

These actions have resulted in a clearer understanding by both PSN and CPCo of the level of QA/QC required, the presence of both a PSN QC inspector and an independent CPCo inspector (from the Nuclear Performance Assessment Department) at the concrete pours for casks Nos. 5 through 8, and increased management attention to all activities involved in or by this project.

Proof of the effectiveness of these actions to eliminate those pre-existing weaknesses was evident as determined by subsequent review of documentation of the fabrication of VCCs 5 through 8 and observation of the concrete pours for VCCs Nos. 5, 6, 7, and 8 where documentation was found to be complete and the pours performed in compliance with the applicable ACI standard.