IR 05000249/1978012
ML17252B131 | |
Person / Time | |
---|---|
Site: | Dresden ![]() |
Issue date: | 09/01/1978 |
From: | Reed C Commonwealth Edison Co |
To: | Fiorelli G NRC/RGN-III |
References | |
IR 1978012 | |
Download: ML17252B131 (18) | |
Text
,* -:. Commonwealth Edison One First National Plaza. Chicago. Illinois Address Reply to: Post Office Box 767 Chicago, Illinois 60690 September 1, 1978 Mr. Gaston Fiorelli, Chief Reactor Operations and Nuclear Support Branch U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137 Subject: Dresden ........ Supplementa esponse to E Inspection Report No. 50-249/78-12 NRC Docket No. 9 References {a) : letter to B. Lee, Jr. dated August 1, 1978 (b): c. Reed letter to J. G. Keppler dated June 27, 1978
Dear Mr. Fiorelli:
In*response to Reference (a), we agree that Appendix materials which may have a direct effect on the outcome of the containment Integrated Leak Rate Test should be an integral part of the test procedure. Specifically, those equations and assumptions upon which the ILRT computer program is based, and a diagram indicating the number of sensors located in each ILRT subvolume, should be included in the procedure. We also agree that any change in sensor location should receive a review as a temporary procedure change. The Dresden ILRT procedure will be revised by October 1, 1978 to include these items. However, we do not consider it appropriate to include within the procedure those test elements which, by their nature, must remain -flexible in order to respond to unusual test situations or which do not affect the outcome of the test. Data entry methods, formats, and types of computational machines used are all examples of those areas which must remain flexible so as not to inhibit test personnel from the successful and timely completion of the test.
Commonwealth Edison NRC Docket No. 50-249 Mr. Gaston Fiorelli: -2 -September 1, 1978 Therefore, we do not believe that the actual computer program should be a part of the procedure. We will, however, make the program available whenever necessary during the test for informational purposes. As committed in our previous letter, (Reference (b)) regarding changes to the computer program, a change will be made only after a review is performed which is commensurate with the same level of review given other temporary procedure changes. Very truly yours, C . \ Cordell Reed Assistant Vice-President T .. / UNITED STATES NUCLEAR REGULATORY COMMISSION REGION Ill Docket No. 50-249 799 AOOSEVEL T ROAD GLEN ELLYN, ILLINOIS 60137 AUG 1 1978 Commonwealth Edison Company ATTN: Mr. Byron Lee, Jr. Vice President Post Office Box 767 Chicago, IL 60690 Gentlemen: Thank you for your letter dated June 27, 1978, informing us of the steps you have taken to correct the item of noncompliance identified in our letter of June 7, 1978. Your response has been reviewed and discussed within our office. For clarity, the response has also been discussed on the telephone with members of your office. It is our that appendix material which may have an effect on the outcome of the containment integrated leak rate test (CILRT) is an integral part of the procedure. Therefore, on site review and formal temporary procedure change documentation would be required by Technical Specification 6.2.D.3. The use of a temporary procedure change document is warranted for changes to the CILRT procedure but final documentation about mentation sensor placement and location need not be available for review until final containment closeout, just prior to pump up. Use of the temporary procedure change will insure that deficiencies in the test procedure will be corrected and made available for other facilities' consideration throughout your system. Our original classification of the noncompliance as an infraction was based on failure to document a change to a safety related test procedure according to DAP 9-2. At this point in time, with all the information available, we agree with you that a deficiency more accurately describes this event, and we will reclassify this item of noncompliance. f-ILlS
,-. _r ** -2 -AUG 1 1979 PleaM euaine )'Otar June 27, 1978 naponea with regard to oar position tllat appendix -terial l:aaviDg an affect OD the outcome of the CU.RT 18 part of U. orlaiDal procedure and -t be bandled accorcliag to existing Station Tec:haical SpeeifiA:atiODS. Ve will &J,adly *18C"BB any C1Wtions JO* llave regarding U... that have Mell *lacuued 1D this latter. We await Joar respoue. ce: Cercl.U leecl, AaBi.euat Viea Pr .. ident llr. S. I. Stephenson, Statioa S11PC'1Dten4at cc w/ltr dtd 6/27/78: I Ceatral Fil* l.eproductioD Unit nc 20b PDR Local PDR ntc TIC Anthony Jloiamaa, laq ** Attorney SiDctlrely, C..toD Fiorelli, adef 1haetor Operatiou ad lluclear Sapport Branch .... NRC Form 3188 m) (1*78) NRCM 0240 *U.S. OOVERNMENT PRINTING OFFICE* 11171-2U-817 e Commonwealth Edison One First National Plaza. Chicago. Illinois Address Reply to: Post Office Box 767 Chicago, Illinois 60690 Mr. James G. Keppler, Director Directorate of Inspection and Enforcement -Region_ III *June 27, 1978 u.s. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 Subject: Dresden Station Unit 3 Response to IE Inspection Report No. 50-249/78-12 NRC Docket No. 50-249 Reference (a}: letter to B. Lee, Jr. dated June 7, 1978
Dear Mr. Keppler:
The following is in response to an inspection conducted by Messrs J. E. Kohler and L. A. Reyes on May 1-3 and 9, 1978 of activities at Dresden Station Unit 3. Reference (a} indicated that one item appeared to be in noncompliance with NRC requirements. Our response to this item is enclosed in the attachment to this letter. The noncompliance was issued for failure to document a change to the computer model used in the Unit 3 containment leak rate test. The change permitted the reactor vessel flange temperature to be used as temperature indication of the volurne within the reactor vessel, rather than using the shutdown cooling loop as originally intended in the model. This change was necessary because an unusual system valve lineup during refueling maintenance testing resulted in the vessel flange area temperature not being accurately represented by the shutdown cooling temperature. After a review of the event, it is agreed that the change should have been formally documented by an On-Site Review similar to that which would have occurred had the procedure for making temporary procedure changes been followed. The change was not made
\)" e Commonwealth Edison NRC Docket No. 50-249 Mr. James G. Keppler: -2 -June 27, 1978 arbitrarily, however, or without proper consideration of its effect by personnel who could have authorized the change. As discussed at the exit meeting, decision to change temperature recorders was made after review and concurrence by the Tech Staff cognizant engineer, the Tech Staff Lead Engineer for Unit 3, the Tech Staff Supervisor, and the Operating Engineer for Unit 3. These people agreed, as did the inspector, that the change would result in a more accurate determination of the contairunent leak rate. To ensure the change was not the determining factor in meeting the leakage specification, it was decided that the leak rate would also continue to be calculated using the shutdown cooling temperature as originally intended. The leakage rate calculated using this temperature was, in fact, within specification. It is believed a thoroµgh review of the change was made, the change was carefully documented in the CILRT Log Book and that the failure to conduct an official on-site review should be classified as a deficiency. we, therefore, request that your Staff reclassify this item as a deficiency rather than an fraction. As requested in Reference (a), a note will be added to the CILRT procedure requiring that any change to the CILRT instrumentation, sensor placement, or computer program will be made only after a review is performed which is commensurate with the same level of review given other normal temporary procedure changes. The note will further specify that should there be changes to CILRT instrumentation sensor placement or computer program, these changes will be clearly entered into the CILRT Log Book under a separate section titled "Special Changes". Furthermore, the CILRT test director will have on site, and available for inspection, a diagram of sensor placement within the contairunent and a simplified flow diagram of the CILRT computer program. The corporate computer Systems Department has been requested to provide Dresden with that description by September 1, 1978. The procedure will be revised by October 1, 1978. Very truly yours, Assistant Vice-President attachment
<)" .e Commonwealth Edison NRC Docket No. 50-249 ATTACHMENT NONC0MPLIANCE--Technical Specification 6.2.D.3 requires that changes to procedures be documented. Dresden Administrative procedure OAP 9-2 requires that changes to procedures be documented on a QP Form 5-51-3. Contrary to the above, on May 2, 1978, changes were made to the containment integrated leak rate test model referenced in the Integrated Leak Rate Test (ILRT) procedure and there was no formal documentation of the changes. DISCUSSION The Integrated Leak Rate Test (ILRT) procedure which has been used at Dresden for past tests does not include the exact location of each ILRT sensor placed within the containment. Since the placement of these sensors is unique to each ILRT and is a function of many variables, sensor placement is not determined until shortly before the test and usually well after the ILRT procedure has completed on-site review. Historically, therefore, the ILRT procedure has not. included the exact sensor location, although the locations are clearly stated in the test report submitted to the NRC. Reactor temperature is controlled during the test by the shutdown cooling system. During the May 2, 1978 Unit 3 ILRT, shutdown cooling water was inadvertently directed through the reactor recirculation pumps instead of the reactor core. Although the problem was corrected before the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> portion of the ILRT began, valuable critical path time was lost while the reactor containment temperature stabilized. To reduce the necessary stabilization period, and permit accurate measurement of the containment subvolume which is above the reactor core and under the reactor head, the decision was made to measure the subvolume in question by selecting a thermocouple mounted on the reactor head and substituting that temperature into the ILRT calculations rather than using the RTD which exists in the shutdown cooling The decision to change temperature sensors was made only after the test director had verified that the thermocouple temperature recording instrumentation was recently calibrated to NBS standards. The Unit 3 Tech Staff Lead Engineer, the Unit Operating Engineer and the Tech Staff Supervisor reviewed and agreed that the instrument change would yield more accurate test
\;* Commonwealth Edison NRC Docket No. 50-249 -2 -results. To ensure that both sensors would verify that measured containment leakage was well within the Unit 3 Tech Specs, complete leak rate calculations were made using both sensors. As predicted, the containment leakage was well below the maximum allowable leakage for both sets of calculations. The procedure was reviewed by the test director and the Tech Staff Supervisor to determine if a procedure change was needed, but since the location of the temperature detectors was not in the procedure, they decided no temporary change was required * . CORRECTIVE ACTION AND CORRECTIVE ACTION TO PREVENT RECURRENCE To ensure that future Integrated Leak Rate Tests continue to maintain control and documentation of any changes to sensor placement or computer program, a note will be added to the CILRT procedure that will instruct the test director to document any changes in the CILRT Log after conducting a review which is commensurate with the same level of review given other normal temporary procedure changes. To insure that all Dresden . personnel involved in the successful completion of the CILRT can perform a satisfactory review of a change to sensor location or computer program, a simplified flow diagram of the computer program and diagram of sensor location will be made available during T.he CILRT. DATE OF FULL COMPLIANCE The procedure will be revised to include the notation on documentation by October 1, 1978. This date has been determined as to permit a mathematical description of the model programmed into the computer to be developed by our Computer Systems Department.
T r 1; * "--'1'! f':* 1 UNITED STATES NUCLEAR REGULATORY COMMISSION REGION 111-Docket No. 50-249 799 ROOSEVELT ROAD GLEN ELLYN, ILLINOIS 60137 JUN 7 1978 Commonwealth Edison Company ATTN: Mr. Byron Lee, Jr. Vice President P.O. Box 767 Chicago, IL 60690 Gentlemen: This refers to the inspection conducted by Messrs. J. E. Kohler and L. A. Reyes of this office on May 1-3 and 9, 1978, of activities at the Dresden Unit 3 Nuclear Power Station authorized by NRC Operating License No. DPR-25 and to the discussion of our findings with Mr. B. Stephenson at the conclusion of the inspection. The enclosed copy of our inspection report identifies areas examined during the inspection. Within these areas, the inspection consisted of a selective examination of procedures and representative records, observations, and interviews with personnel. During this inspection, certain of your activities appeared to be in noncompliance with NRC requirements, as described in the enclosed Appendix A. It was noted that the detailed description of the containment model and the corresponding computer program used to calculate the tainment leak rate were not included in the procedure used by the station during the Dresden Unit 3 leak rate test. It is our position that the computer model as described or referenced by the procedure is part of the detailed CILRT procedure and changes to the model are subject to technical specifications regarding changes to procedures. In your response to this inspection report, please include your plans to document the leak test model in the Dresden 2/3 CILRT procedure. 'This notice is sent to you-pursuant to the provisions of Section 2.201 of the NRC's "Rules of Practice," Part 2, Title 10, Code of Federal Regulations *. Section 2.201 requires you to submit to this office within twenty days of your receipt of this notice a written statement or explanation in reply, including for each item of noncompliance: (1) corrective action taken and the results achieved; (2) corrective action to be taken to avoid further noncompliance; and (3) the date when full compliance will be achieved.
. s!.\, _,-.f I i Cominonwealth Edison Company --2 -JUN 7 1978 In accordance with Section 2.790 of the NRC's "Rules of Practice," Part 2, Title 10, Code of Federal Regulations, a copy of this letter, the enclosures, and your response to this letter will be placed in the NRC's Public Document Room, except as follows. If the enclosures contain information that you or your contractors believe to be proprietary, you must apply in writing to this office, within twenty days of your receipt of this letter, to withhold such information from public disclosure. The application must include a full *statement of the reasons for which the information is sidered proprietary, and should be prepared so that proprietary information identified in the application is contained in an enclosure to the application. We will gladly discuss any questions you have concerning this inspection.
Enclosures:
1. Appendix A, Notice of Violation 2. IE Inspection Rpt No. 50-249/78-12 cc w/encls: Mr. B. B. Stephenson, Station Superintendent Central Files Reproduction Unit NRC 20b PDR Local PDR NSIC TIC Anthony Roisman, Esq., Attorney
Sincerely,Gaston Fiorelli, Chief Reactor Operations and Nuclear Support Branch r SURNAME ... ----------------------------------__ &70 ______ _ RIII RIII --------------Fiorelli Barker --------------... ____ NRC Form 3188 (Rm) (1-78) NRCM 0240 *U.S. GOVERNMENT PRINTING OFFICE' 1978-253*817
.... Appendix A NOTICE OF VIOLATION Commonwealth Edison Company Docket No. 50-249 Based on the inspection conducted on May 1-3 and 9, 1978, it appears that certain of your activities were in noncompliance with NRC ments, as noted below. This constitutes an item of noncompliance of the infraction level. Technical Specification 6.2.D.3 requires that changes to procedures be documented. Dresden Administrative Procedure DAP 9-2 requires that changes to procedures be documented on a QP Form 5-51-3. Contrary to the above, on May 2, 1978, changes were made to the Containment Integrated Leak Rate Test model referenced in the CILRT procedure and there was no documentation of the changes.
U.S. NUCLEAR REGULATORY C_OMMISSIO_N OFFICE OF INSPECTION AND ENFORCEMENT REGION III Report No. 50-249/78-12 Docket No. 50-249 License No. DPR-25 Licensee: Corrunonwealth Edison Company P. O. Box 767 Chicago, IL 60690 Facility Name: Dresden Nuclear Power Station, Unit 3 Inspection At: Dresden Site, Morris, IL Inspection Conducted: May 1-3 and 9, 1978 Inspectors: J. E. Kohler f.£. L. A. Reyes ----_ _.._ Approved By: J. F. Streeter, Chief Nuclear Support Section 1 Inspection Summary Inspection on May 1-3 and 9, 1978 (Report No. 50-249/78-12) Areas Inspected: Routine, announced inspection of the 1978 CILRT at Dresden Unit 3. The inspection involved 43 inspector-hours on site by two NRC inspectors. Results: One item of noncompliance (infraction failure to document a change to the CILRT procedure -Paragraph 8).
1. DETAILS Persons Contacted B. Stephenson, Station Superintendent D. Farrar, Tech Staff Supervisor M. Wright, Tech Staff C. Sargent, Unit 3 Operating Engineer P. Duggan, CILRT Lead Engineer D. Smith, Tech Staff Engineer M. Parcell, Tech Staff Engineer G. Reimers, Tech Engineer J. Actenberg, Tech Staff Engineer C. Young, Commonwealth Edison Company B. Shelton, Administrative Assistant, Dresden R. Kyrouac, QC Commonwealth Edison, Dresden G. Reardanz, Commonwealth Edison QA Coordinator 2. 1978 Unit 3 CILRT The 1978 Dresden Unit 3 Containment Integrated Leak Rate Test (CILRT) was performed during a. 12-hour period on May 2, 1978. At the conclusion of the test, the licensee measured a leak rate at the 95% confidence level of approximately 0.4505 weight percent per day (W/O/DAY). Technical Specifications and 10 CFR 50 Appendix J requires the containment leak rate to be less than 1.2 W/O/DAY at 48 psig. 3. Supplemental Test At the conclusion of the CILRT, a supplemental test of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> duration was performed. An induced leak rate equivalent to approximately 0.393 W/O/DAY was superimposed. The licensee measured approximately 0.716 W/O/DAY. This is within the 25% La criteria specified in 10 CFR 50 Appendix J and is tory of the measurement obtained during the 12-hour CILRT. 4. Instrumentation Calibration records for the following were reviewed by the inspector: 29 RTD's 2 flow meters 10 dewcells 2 pressure gauges -2 -
. --* A multi-point calibration of all instrumentation and an instrumentation error analysis were performed by the licensee. No problem areas were identified. 5. Inspector Leak Rate Calculation During the test, the inspector randomly selected various data points and checked the mass calculation. There was acceptable agreement between the licensee's mass point leak rate tion and the inspector's as indicated in the following summary of the leak rate calculation. Licensee Inspector 12-hour Test W/O/DAY (95% Upper Confidence Level) .4491 . 4505 6. Shutdown Cooling Valve Lineup Error Supplemental Test W/O/DAY (Calculated Leak Rate) * 7163 . 7175 A deficiency in the valve lineup was detected during.the CILRT which caused an increase in the test duration. At about 1200 on May 1, approximately 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> after reaching test pressure, reactor vessel flange temperature was at approximately 300°F and was discovered to be on an increasing trend. This temperature was recorded in the control room. Because one loop of shutdown cooling was inservice at the time, recording a temperature of approximately 160° F, the flange temperature have been approximately equal to the shutdown cooling shell temperature. The temperature difference between the shell and the flange could not be explained. In order for shutdown cooling to pass through core, recirculation pump discharge and suction valves must either be closed and the recirculation pump off, or both valves open and the recirculation pumps running. Investigation by the station revealed the following: Pumps off, suction and discharge valves open. This lineup resulted in the majority of shutdown cooling water flow circulating through the recirculation pump and not through core. Upon discovery by the licensee, the suction and discharge valves were closed. The licensee investigated the events which contributed to the irregular shutdown cooling water valve lineup. It was mined that the maintenance department had completed ment of the brushes on the recirculation pump M-G sets. As a result of the post maintenance testing, a 36-hour run test had to be performed on the pump motors. -3 -
7. The recirculation pump was uncoupled from the pump motor, and the motors were run. However, the recirculation system logic gives trip signal to the pump motor if the suction and discharge valves are closed and the pump gets a start signal. Consequently, in order to perform a 36-hour test, maintenance personnel opened the suction and discharge valves. Results of Shutdown Cooling Valve Lineup Error on CILRT Because shutdown cooling was not aligned properly, the vessel flange began to heat up. This heatup caused a temperature and pressure increase in the drywell. The computer program used to calculate the containment leak rate was using shutdown cooling temperature as an indication of conditions inside the vessel. Therefore, as the flange began to heat up, the down cooling temperature was not accurately representing this subvolume (reactor vessel) temperature. With the increasing pressure and temperature inputs, the computer program ously concluded that there was a large inleakage condition. Approximately 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> after recording of data pegan, the shutdown cooling valve lineup was restored to the correct mode. At the same time, a change was made to the computer program to use the vessel flange temperature for the vessel subvolume. With shutdown cooling restored, the flange began to cool off. This caused the drywell pressure and temperature to decrease which resulted in the computer program calculating a large leak rate. Based on the station's definition of start time of the test, official data could not be taken until the leak rate had lized. The transient introduced into the drywell atmosphere because of the shutdown cooling valve lineup error considerably lengthened the test. The licensee changed the procedure for aligning shutdown cooling to require positive indications that suction or discharge valves are closed when the recirculation pump and pump motors are off. In addition, the licensee will consider a plant modification to enable an RTD to be placed within the vessel air space so that future approximations of this subvolume temperature and dewpoints do not have to be made. The inspector stated that the licensee should apprise other stations of this transient so that the event is not duplicated during other containment tests. -4 -
--Inadequate CILRT Procedure The licensee did not include in the CILRT procedure a detailed description of the computer model used to calculate the leak rate. During the test the licensee made changes to the computer model but did not make these changes using established trative procedures for a procedure change. The changes to the computer model involved using vessel flange temperature instead of shell temperature for the subvolume within the vessel. Failure to document changes to the CILRT procedure constitutes an item of noncompliance against Technical Specification 6.2.D which deals with temporary procedure changes. By not having a documented, detailed description of the computer model, the licensee was forced to rely on the memory of his people to determine how the computer model worked. Unfamiliarity with the model resulted in erroneous information being given out by station personnel and manpower being directed away from more important functions during the test. 9. Test Coordination Between Various Station Departments There were problems encountered with test coordination between the operating and technical staffs. For example, the technical staff was not informed about a decision which had been made by the operating department not to flood up the vessel to cool the vessel head. In addition, the technical staff was not informed why letting the moderator temperature equilibrate with the flange temperature was disregarded by the operating staff. Failure of the operations staff to keep the technical staff running the test fully resulted in the technical staff not being able to answer questions or properly direct manpower. The inspector stated that test coordination could be improved by analyzing the effect on the test of work performed by other groups during the test. For example, the maintenance department work on the recirculation pumps. 10. RCCCW Valve During the test, it is essential that the shutdown cooling system be in operation to maintain a stable reactor temperature. In no case should the system be cycled on and off as this creates drywell temperature instability. -5 -
The valve used to control shutdown cooling, valve V-3704, is a gate valve. Gate valves do not normally have intermediate opening positions. For the purposes of this test, the leads were lifted from the valve and connected in such a way as to permit intermediate valve position opening. Difficulty was experienced in maintaining shutdown cooling temperature stability throughout the test. The cause could be attributed to the control system and the valve in the shutdown cooling system. The inspector stated that the licensee should consider a modification to the shutdown cooling system which substituted a globe valve for the existing gate valve and a modification of the controller. The licensee stated that just changing the gate valve to a globe valve would be making a considerable improvement and that such a modification would be considered. 11. Equipment The licensee used the latest automated equipment for monitoring the CILRT. Problems developed during the test because of sporadic operation of the paper tape machine. The faulty operation caused the licensee to enter data by hand which resulted in the licensee falling behind in analysis of data during the transient. Decisions were being made during transient analysis with an incomplete record. It was later discovered that some of the paper tape machine malfunctions were attributed to incorrect character definition being input into the tape machine. This resulted in the tape machine incorrectly encoding the data. The licensee is using sophisticated equipment for monitoring the leak rate. The inspector stated that in order for the licensee to use this equipment efficiently, spare parts should be stocked so that equipment malfunctions can be made corrected with minimum impact on the test. The licensee used onsite computer facilities during the test which periodically became unavailable because of other dedicated functions. The inspector stated the licensee should consider obtaining dedicated computer facilities for the CILRT to assure the test can be run in a minimum amount of time. 12. Corporate Involvement Since 1976 the integrated leak rate test has been run at the Dresden Station three times. The inspector has noted each -6 -
time that the test has been run with many new people. In essence, a new tech staff team is per-forming the test each time. The inspector discussed with the licensee the advantages of the corporate office developing leak rate testing expertise in order to assist in the analysis and interpretation of the data. In addition, the corporate office could more usefully feed back problems that are relevant to other stations. The corporate office test expertise could cover data analysis, instrumentation and operation, calibration requirements, and NRC and station regulations. The licensee stated that other complex infrequent surveillance tests were already being performed by the corporate office, such as turbine testing. He stated that the inspector's suggestion regarding corporate involvement in the leak rate testing would be considered. 13. Twelve-Hour Test Duration Technical Specification Change The licensee submitted a *tech spec change to the NRC which defined the acceptance criteria to be used to run a 12-hour integrated leak rate test. This criterion dealt with temperature stabilization, minimum number of data points, and containment leak rate stabilization. After the leak rate stabilized at the station, a 12-hour data interval was used as the official test period. The leak rate test extended through a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as required by Tech Spec 4.7.A.2. 14. Test Duration Although the station revised the procedure for performing the 12-hour test, the containment was at pressure for over 65 hours7.523148e-4 days <br />0.0181 hours <br />1.074735e-4 weeks <br />2.47325e-5 months <br />. The valve lineup error in the shutdown cooling system extended the test duration 30-35 hours. This could have been avoided through better station coordination. 15. Exit Interview An exit interview was conducted on May 9, 1978, in which Mr. Kohler summarized the results of the inspection. -7 -