ML20138C224

From kanterella
Jump to navigation Jump to search
Responds to NRC Re Violations Noted in Insp Repts 50-338/85-28 & 50-339/85-28.Corrective Actions:Calibr hi-lo Thermometers Obtained & Will Be Used for Monitoring Field Curing Temp in Future Work.Summary Rept Encl
ML20138C224
Person / Time
Site: North Anna  Dominion icon.png
Issue date: 03/21/1986
From: Stewart W
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To: Grace J
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20138C230 List:
References
86-131, NUDOCS 8604020406
Download: ML20138C224 (7)


Text

r s'

YINUINIA 1$LECTMIC AND l'OWI N COMl'ANY Nttnaxoxp.Vinois:A uttunt r

'a W.L STEWANT -

Ne*CLEAm Oramations March 21, 1986 Dr. J. Nelson Grace Serial No. 86'T$1 Regional Administrator N0/DJV/vlh Region II Docket Nos. 50-338 U. S. Nuclear Regulatory Commission 50-339 Suite 2900 License Nos. NPF-4 101 Marietta St., N.W. NPF-7 Atlanta, Georgia 30323

Dear Dr. Grace:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS NO. 1 AND 2 NRC INSPECTION REPORT NOS. 50-338/85-28 and 50-339/85-28

, We have reviewed your letter of February 21, 1986, in reference to the inspection conducted at the North Anna Power Station on October 26 through November 1, 1985. Our response to the Notice of Violation is addressed in Attachment 1.

In response to the oral commitments we made during the enforcement conference on December 18, 1985, we are providing in Attachment 2 a report on design of the select backfill placed around the buried service water piping. In addition, the inspection of the in place concrete surface for the service water valve house structure has been completed and defects will be repaired in accordance with our specification (NAS-2029) for concrete placement.

We have determined that no proprietary information is contained in the inspection report. Accordingly, we have no objection to this report being made a matter of public disclosure.

Very truly yours, t ,.

.[./ I e a .3 / M.

.W. L. Stewart v

Attachments

1. Response to Notice of Violation
2. Report on Design of Select Fill h.

DOC ik

VamotwlA ELrcture ano Powan CowrAwy to Dr. J. Nelson Crace cc: Mr. Lester S. Rubenstein, Director PWR Project Directorate #2 Division of PWR Licensing-A Mr. Morris V. Branch NRC Senior Resident Inspector North Anna Power Station 1

U- )

ATTACIIMENT l' RESPONSE TO NOTICE OF VIOLATION INSPECION REPORT NOS. 50-338/85-28 AND 50-339/85-28 VIOLATION:

10 CFR Part 50, Appendix B, Criterion V, requires that activities affecting quality shall be prescibed by documented procedures or drawings of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, and drawings.

10 CFR Part 50, Appendix B, Criterion XVII, requires that sufficient records shall be maintained to furnish evidence of activities affecting quality.

Contrary to the above, during the period of June 17 through November 1, 1985, modification to the service water intake structure which is listed on the North Anna Q-List was not always accomplished in accordance with instructions or proc.edures and sufficient records were not always maintained as evidenced by the following examples:

1. Specification NAS 2029, Placement of Concrete and Reinforcing Steel, required concrete test cylinders to be controlled in accordance with ASTM C31, Making Curing Concrete Test Specimens in the Field. This ASTM requires cylinders which are initially cured in the field to be maintained at a temperature of 60' to 80'F for the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and -

indicates that a temperature record of the test specimens may be established by means of maximum-minimum thermometers. Following the initial 24-hour curing period, the test cylinders are then required to be stored in a moist condition in the laboratory at 73.4'F 3'F until the moment of test.

However, no temperature records were maintained to verify that the test cylinders were initially cured in the field at 60'F to 80'r for

. the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. In addition, records from October 28 through November 1, 1985, that were kept for the time following the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> curing period showed that the test cylinders were not stored at 73.4'T 13'F.

2. Specification NAS 3003, Excavation Fill and Backfill, Service Water Buried Piping Installation, paragraph 3.5.2, required select fill moisture to be controlled to i 3 percent of the optimum moisture as determined by. ASTM D 698, Moisture Density Relations of Soils using 5.5 lb. Rammer and 12 inch Drop.

~. -

However, examination of records for select fill placed on August 27, 1985, September 18, 1985, September 19, 1985, and September 25, 1985, showed that moisture was not controlled ati 3 percent of the optimum moisture as determined by ASTM D 698 requirements.

3. Specification NAS 2014, Supply of Materials Batching, Mixing, and Delivery of Ready Mix Concrete, specified that tests for slump, air content, and concrete temperature shall be made for each truck delivered; that the amounts of fine and coarse aggregate and water shall be shown on the batch tickets; that aggregate gradation tests shall be performed daily; and that the maximum amount of air entraining agent for the current design mix is 5.4 ounces per cubic yard of concrete or 44 ounces for an 8 cubic yard load.

However, from June to November 1985, Specification NAS 2014 was not followed in that tests for slump, air content, and concrete temperature were not consistently made for each truck of concrete delivered in thatt the amount of fine and coarse aggregate were not shown on batch ticket invoice numbers 31876 to 31879 and 31885 dated June 17,1985 ; the amounts of water and fine and coarse aggregate were not shown on batch ticket invoice numbers 32021 to 32023 dated July 31, 1985; samples for daily gradation tests were being taken, but testing was about one month behind schedule; and the maximum allowable amount of air entraining agent shown on the batch tickets was 48 ounces for an 8 cubic yard load instead of the 44 ounces specified by the design mix.

4. Procedure QC 10.1, Civil Inspection, was used to control the inspec-tion and documentation of work-related civil activities.

However, Procedure QC 10.1 was not appropriate for the circumstances in that it did not reference the current specifications being used to control concrete and compaction of soils in the modifications to the service water intake structure.

Collectively, the above violations have been categorized in the aggregate as a Severity Level III problem (Supplement I).

RESPONSE

1. ADMISSION OR DENIAL OF THE VIOLATION This violation is correct as rtated.

I 4

s -

2. REASON FOR THE VIOLATION The reasons for each of the specific deficiencies noted .in the examples of the Violation are as follows:
1. Temperatures were not monitored in the field during the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as required by the specification because operable hi-lo thermometers had not been supplied to the service water reservoir project job site.

The QC inspector assigned to the civil activities did write a Nonconformance Report (NCR) which identified that the curing room temperature had been outside of the acceptable range. However, the disposition of the NCR, while addressing the immediate concern with the effect of the temperature variation on the affected samples, did not address resolution of the cause of the temperature being outside the acceptable range (i.e. the temperature control system was not operating properly).

Therefore, the inspector was lead to an incorrect conclusion that out-of-specification temperature variations of the curing room could be tolerated. Problems with the temperature control system included clogged spray heads and water filters which reduced the flow of water into the room, and non- functioning heating elements in the hot water heater.

2. The material which failed to meet moisture requirements was reworked and the QC inspector believed that he had adequately ratested the failing materials. However, available documentation does not prove this to be the case since the rework was not properly recorded.
3. Dif ferences in required test f requencies between NAS 20*.4 and NAS 2029 lead to confusion on the part of the QC Inspector. The inspector chose to follow the concrete placement specification (NAS 2029) and f ailed to identify the apparent discrepancy to either his supervision or Engineering for resolution. The concrete supplier's inspector initially was not aware of the importance of showing the actual amounts of fine and coarse aggregates, resulting in blank spots on batch tickets during the i first placements. An insufficient nurber of QC inspectors (1)

I was assigned to perform all field and lab concrete and sot ts

, inspections and tests, thus the reason for gradation samples taken but not tested. Air entrainment dose rates occasionally need to be adjusted to compensate for varying ambient j temperatures and other factors which affect the air content of l fresh concrete, In order to obtain the desired air content, air i entrainment dosages did vary from the laboratory trial batch l design dosages.

{ 4. Procedures were in the process of being developed. liowever, the i

one QC inspector assigned to perform all of the concrete and soils testing and inspection was also the individual assigned to write the concrete and soils procedures. The inspector's time was spent totally on testing and inspection activities, leaving no timo for him to develop the procedures.

The root cause of the Violation has been attributed to a lack of management involvement in the project and control of the QA program.

3. CORRECTIVE STEPS TAKEN AND RESULTS ACHIEVED The actions taken to address the specific deficiencies noted in the examples of the Violation are as follows:
1. Calibrated hi-lo thermometers have been obtained and will be used for monitoring field curing temperatures in future work.

Maintenance has been performed on the temperature control / recording system in the QC lab and the temperature recorder has been recalibrated. The curing room controller /

recorder has been operating correctly (maintaining 73.4'Fi 3'F) since the maintenance was performed. To avoid future problems, the recording chart is monitored more frequently and regular maintenance is performed on spray heads and water filters.

2. Procedures are now in place to control the testing of backfill.

No further Category I fill placement has occurred since the procedures were issued so results achieved cannot t.e measured yet. To assure placement of fill is done correctly in the future, we are stressing procedural compliance to the inspection and testing personnel. Additionally, a test report review cycle is now required by the procedures to further assure compliance.

3. NAS 2014 and NAS 2029 have been revised to eliminate potential confusion in test frequencies. Procedures have been issued to further control testing activities. We will now have an inspector at the batch plant during Category I batching operations to ensure that required data is recorded on the batch tickets. An adequate number of inspectors (minimum of four) have been qualified to perform inspections associated with concrete and soils activities. In addition, an independent testing agency has been hired to perform in process materials testing at the batch plant and on-site production testing of concrete, grout and backfill.

Hence, required tests should be performed in a timely manner.

NAS 2014 has been revised to allow the concrete supplier to make adjustments to the air entrainment dose rate so the air content range is adhered to. To assure there are no future violations, procedural compliance is being stressed to QC personnel, and test and inspectiori reports are now required by procedure to be reviewed for accuracy, completeness and adherence to required frequencies.

J

r.-

s a

~

i .

l I
4. Five new Quality Assurance Department Instructions (QADis) have been issued to control the testing, inspection and documentation

! of concrete and soils activities. They are:

! 1. QADI 10.3.1 Excavation and Backfill Testing

2. QADI 10.3.2 Excavation and Backfill Inspection
3. QADI 10.3.3 Concrete Testing
4. QADI 10.3.4 Concrete Inspection
5. QADI 11.1 Calibration of Soils, Concrete &

Aggregate Testing Equipment Other actions taken to address the root cause of the Violation include:

5. Management's role and supervisory involvement in inspection activities have been improved through establishment of methods
for in process monitoring of inspection activities. The methods

( include: inspector weekly reports, bi-weekly meetings, and l scheduled time for coordinators and supervisors to spend in the i tield.

4. CORRECTIVE STEPS WilICli WILL BE TAKEN TO AVOID FURTifER VIOLATIONS An audit checklist for assessing the adequacy of the concrete and soils program is presently under development. Approximately one month after resumption of the service water construction work, a formal audit will be conducted using this checklist. In addition, two of the new Quality Assurance Department Instructions (QADI) noted in the previous section include monitoring checklists which will be used on an ongoing basis to verify compliance to QA program requirements.
5. DATE WHEN FULL COMPLIANCE WILL BE ACl!!EVED An audit for assessing the adequacy of the concrete and soils program will be conducted af ter resumption of work to confirm that all prework planning is adequately being implemented.