IR 05000443/1998002

Insp Rept 50-443/98-02 on 980329-0516.No Violations Noted. Major Areas Inspected:Operations,Engineering,Maint & Plant Support

ML20249B065
Person / Time
Site:	Seabrook
Issue date:	06/12/1998
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20249B063	List: IR 05000443/1998002 ML20249B062
References
50-443-98-02, 50-443-98-2, NUDOCS 9806220027
Download: ML20249B065 (20)

Text

\

.

.

U. S. NUCLEAR REGULATORY COMMISSION

REGION I

Docket No.: 50-443 License No.: NPF-86 l-Report No.: 50-443/98-02 Licensee: North Atlantic Energy Service Corporation Facility: Seabrook Generating Station, Unit 1 Location: Post Office Box 300 Seabrook, New Hampshire 03874 Dates: March 29 - May 16,1998 Inspectors: Ray K. Lorson, Senior Resident inspector Javier Brand, Resident inspector Approved by: Curtis J. Cowgill, Chief, Projects Branch 5 Division of Reactor Projects

"

9906220027 990612 PDR ADOCK 05000443 G PDR i

.

. , .

I EXECUTIVE SUMMARY Seabrook Generating Station, Unit 1 i NRC Inspection Report 50-443/98-02 This integrated inspection included aspects of licensee operations, engineering, maintenance, and plant support. The report covers a 8-week period of resident inspectio _

. Ooerations:

• Routine operations were performed in accordance with station procedures and plant evolutions were completed in a deliberate manner with clear communications and effective oversight by shift supervisio * The field walkdown program continued to be effective at identifying minor equipment issues as highlighted by the large number of equipment deficiencies tags generate * Several performance deficiencies were noted during review of the steamline pressure channel calibrations. This issue remains unresolved pending resolution of the calibration methodology questions being investigated by the license (Unresolved item 98-02-01).

Maintenance:

• The troubleshooting of the personnel access hatch hydraulic control valves and replacement of the mechanicalinterlock cable were performed well. Excellent briefings were observed, and the mechanics were well prepared to perform the planned evolution * The licensee implemented an aggressive inspection criteria for detecting sparking emergency diesel generator brushes. Upon identification of minor sparking, the licensee promptly evaluated the condition, determined that operability of the EDG was not affected, and conservatively decided to replace the affected brushe * The electricians performed well during refurbishment of a safety battery breake * The licensee promptly initiated an investigation for a failed pressurizer sample valve position indication, and implemented appropriate corrective action Enoineerino:

• . The licensee promptly and adequately evaluated the inspector's concerns, and determined that no immediate concern regarding degradation of the EDG exhaust il

.

.

piping existed. However, the inspector noted some weaknesses in the licensee's method to evaluate the long term reliability of the subject pipin e The system engineer provided good support and analysis of a degraded charging pump drive pin / bushing. The licensee's actions to replace the components and continue with the inspection program were appropriat e The licensee performed well by identifying and investigating questions pertaining to their previous lead / lag ca.d calibration methodology. This issue will remain unresolved pending review of the impact of the initial method on the channel operability. (Unresolved item 98-02-01)

Plant Suonort:

e The radiological controls technicians were observed to be attentive and provided high quality assistance to plant workers. Plant workers were observed to be following proper radiological work practices iricluding use of dosimetry and protective equipment. Personnel briefings prior to containment entries were thorough and informativ * The inspectors observed good security force performance during inspection activities. Protected area access controls were found to be properly implemented during random observations. Proper escort control of visitors was observe Security officers were alert and attentive to their duties.

l l iii

- - - _ - _ _ _ _ __ _ _ - _ ,

.

.

TABLE OF CONTENTS EXECUTIVE SUM M ARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

. TA BLE O F C O NT E NTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv 1. Operations ....................................................1 O1 Conduct of Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 01.1 General Comments (71707) ...........................1 02 Operational Status of Facilities and Equipment ................... 1 02.1 = Facility Tours (71707, 62707) . . . . . . . . . . . . . . . . . . . . . . . . . . 1 04 Operator Knowledge and Performance ' . . . . . . . . . . . . . . . . . . . . . . . . . 1 04.1 Resnonse to Inonerable Steam Generator Pressure Protection Channels

...............................................1 08 Miscellaneous Operations issues (92901) . . . . . . . . . . . . . . . . . . . . . . 3 08.1 (Closed) Insoection Followuo item (IFI) 50-443/97-03-01: ...... 3 11. M ai nt e n a n c e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 .

M1 Conduct of M aintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 M1.1 Containment Personnel Hatch Troubleshooting and Cable Replacement

...............................................4 M1.2 Soarkina of "B" Emeroencv Diesel Generator Rotor Shaft Brushes Durina Surveillance Testina . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 M1.3 Refurbishment of Safety Related 125 Volt DC Breaker . . . . . . . . . 5 M1.4 Pressurizer Gas Soace Samole / Vent Valve Position Indication Failure

...............................................5 M8 Miscellaneous Maintenance issues (92902) .....................6 M8.1 (Closed) Violation 50 443 /9 7-0 3-02 . . . . . . . . . . . . . . . . . . . . . . 6 M8.2 (Closed). Violation 50-44 3 /9 7-06-0 5 . . . . . . . . . . . . . . . . . . . . . 7 M8.3 (Closed) LER 50-44 3/9 8-0 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

.Ill. Engineering ...................................................7 E2 Engineering Support of Facilities and Equipment .................. 7 E Emeroency Diesel Generator Exhaust Pioe . . . . . . . . . . . . . . . . . . 7 E2.2 2B Coolant Charaina Pumo Drive Pin and Bushina . . . . . . . . . . . . 9 E2.3 Lead / Lao Circuit Card Testina . . . . . . . . . . . . . . . . . . . . . . . . . . 9 E8 Miscellaneous Engineering issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 E8.1 (Closed) LER 5 0-44 3 /9 8-02 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 E8.2 (Closed) LER 50-443/97-02-01 ........................11 E8.3 (Closed) LER 50-443/97-016-00. and 97-016-01 ...........11 E8.4 (Closed) Violation 50-44 3/97-04-02 . . . . . . . . . . . . . . . . . . . . . 1 1 IV. Plant Support ...................-............................12 R1 Radiological Protection and Chemistry Controls . . . . . . . . . . . . . . . . . . 12 R1.1 General Comments ................................12

.S1 1 Conduct of Security and Safeguards Activities . . . . . . . . . . . . . . . . . . 12 S1.1 General Comment (71707. 71750) .....................12 iv

_ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ - _ _

_ _ _ _ _ _ _ _ _ - _ - _ - - - - _ - _ _ _ _ - - _ _ _ _ _ -

.

.

V. Management Meetings ..........................................13 X1 Exit Meeting Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 PARTIAL LIST OF PERSONS CONTACTED ' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 '

INSPECTION PRO CEDURES USED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

~ lTEMS OPENED, CLOSED, AND DISCUSSED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 LIST OF ACRONYMS USED .........................................15 l- v-l t:

l-

!

l ..

I'

!

.

.

Report Details Summarv of Plant S' tatus The facility.was operated at approximately 100% of rated thermal power throughout the inspection period with routine minor power reductions performed to support instrument

. calibrations and testin . Operations 01 Conduct of Operations 01.1 General Comments (71707)

Using inspection Procedure 71707, the inspectors conducted frequent reviews of ongoing plant operations. In general, routine operations were performed in

. accordance with station procedures and plant evolutions were completed in a deliberate manner with clear communications and effective oversight by shift supervision. Control room logs accurately reflected plant activities and observed shift turnovers were comprehensive and thoroughly addressed questions posed by

~

the oncoming crew. Control room operators displayed good questioning perspectives prior to releasing work activities for field implementation. The inspectors found that operators were knowledgeable of plant and system statu Operational Status of Facilities and Equipment 0 Facility Tours (71707. 82707)

The inspectors routinely conducted independent plant tours and walkdowns of selected portions of safety-related systems during the inspection report perio These activities consisted of the verification that system configurations, power

- supplies, process parameters, support system availability, end current system

operational status were consistent with TS requirements and UFSAR description Additionally, system, component, and general area material conditions and housekeeping status were noted. The inspectors identified some minor material deficiencies that were appropriately addressed by the licensee. Additionally, the licensee's field walkdown program continued to be effective at identifying minor equipment issues as highlighted by the large number of deficiencies tags generate Operator Knowledge and Performance 04.1 Resoonse to Inonerable Steam Generator Pressure Protection Chanr els Insoection Scone (71707/62707)

The inspector reviewed the plant staff response after three of six "B" and "C" steamline pressure protection channels were found to be outside the procedural calibration limits during surveillance testing. . - _ - _ _ _ _ . _ _ _ _ _ _ - _ _ _ _ _ - _ ---

.

. . -

Observations and Findinas

Each steamline contains three pressure sensing channels that provide input signals into the~steamline low pressure isolation and safety injection logic circuits. Two of the three steamline channels are required to be operable per technical specifications (TSs) to initiate the logic circuitry.'.The channels 'nclude a control card (NLL) that conditions the instrument output signal to allow the protective system response to-lead the process parameter (e.g. steam line pressure). The NLL card response is controlled by lead (T1), and lag (T2) time constants which are set per TS On' April 30 and May 1, instrumentation and controls (l&C) technicians checked the calibration of three of the six "B" and "C" steamline pressure channels and determined that the cards were within the calibration limits. The l&C technicians subsequently reperformed these checks after a supervisor. determined that the

,

existing station method had not been implemented for analyzing the NLL card output

~

response data.' The follow-up calibration checks indicated that the three NLL card lead time constants were outside the procedural calibration limits. The technicians adjusted these cards to within the proper time constant limits. The remaining three

"B" and "C" steamline channels were checked and found to be within the required calibration limits. The licensee did not recognize, at this time, that the required NLL time constant values were specified in TS Table 3.3- On May 4, an engineer reviewed this event and noted that the three initial "as found" NLL lead time values had not satisfied the TS Table 3.3-4 limit. The licensee determined that the three "B" and "C" steamline pressure channels had been

' inoperable, and reported this condition to the NRC on May 5. The inspector noted the high percentage of channels found to be inoperable (three of six) , and

'

questioned the licensee regarding the schedule for checking the calibration of the

. remaining ("A" and "D") steamline pressure channel The licensee indicated that the remaining channels were scheduled to be checked within a week or two. The inspector noted that TSs required an inoperable channel

.to be placed in the " trip" condition within six hours, and was concerned that the s licensee's planned schedule for checking the remaining channels was not adequate

'given the time allotted to complete the TSs required compensatory actions. The-inspector discussed this concern with Station Management, and the licensee subsequently elected to immediately check the calibration of the remaining ll steamline pressure channels. - This testing identified that the lead time constant was out of tolerance on one pressure channel on each of the remaining steamline The inspector noted a number of performance deficiencies during this event including:

• ' The I&C technicians initially analyzed the NLL card response data differently from the approved station method.

y

,

_

_ _ _ . _ _ _ _ . _ _ _ _ _ _ _ _ _ _

.

(

i

.4

• The licensee was slow to recognize that the NLL lead time constants (found out of calibration on May 1) affected the TS operability (recognized on May 4) of the steamline pressure channels.

,

• The licensee did not initiate action to confirm the operability of the remaining l channels after determining the extent of the initial problems until questioned

! by the NRC.

The licensee formed an event team to review this condition. The investigation was on-going at the completion of the inspection period. One of the issues under review (discussed in Section 2.3), involves the calibration methodology utilized to determine the NLL card time constants. The resolution of this issue is central to understanding the potential regulatory nature of this event. This item will remain unresolved pending determination of the impact of the different calibration methodologies on the operability of the instrument channels. Unresolved item (URI)

98-02-01, Conclusions Several performance deficiencies were noted during review of the steamline pressure channel calibrations. This issue remains unresolved pending resolution of the calibration methodology questions being investigated by the license l

'

08 Miscellaneous Operations issues (92901)

08.1 (Closed) Insoection Followuo item (IFI) 50-443/97-03-01: Inadvertent Steam j Generator Draining )

. This issue refers to inadvertent draining of the "C" and "B" Steam Generators (SG's), on June 13,1997, while the unit was in a refueling outage, and the SG's were not required or credited for heat removal. This issue was first documented as an IFl in inspection report 97-03. Additiona'lly, the licensee documented this issue in LER 97-012, dated July 11. This LER was previously reviewed and closed in inspection Report 97-04. The inspector reviewed the licensee's root cause analysis for ACR 97-1543, and verified the corrective actions to be reasonable and complete. These corrective actions included: training operators on the event and associated root cause; continued implementation and development of the human error reduction technology and reinforcement of error reduction techniques, and incorporating the lessons learned into future outage planning. However, the inspector noted a minor deficiency in the licensee's root cause analysis due to the failure to document the potential for and amount of radioactivity released to the environment, during the draining evolutions. The inspector verified that the chemistry department did routinely sample the steam pipe chases for radioactivity, and that samples taken prior to and after the SG draindown showed that lodine (1-131) levels were much lower than the required limit of detection. This inspection  ;

followup item is close I

l

_ _ _ . _ __ _ __ a

.:

.

4-

- II. Maintenance M1' .' Conduct of Maintenance .

- M1.1. Containment Personnel Hatch Troubleshooting and Cable Replacement inspection Scope

- On April 20 and 22, the inspector observed portions of maintenance activities to troubleshoot the personnel hatch hydraulic fluid control valves and to replace the damaged mechanical interlock cabl Observations and Findmgs Troubleshooting of the subject hydraulic fluid control valves was performed to determine the root cause for premature personnel hatch mechanical interlock cable failures. The inspector attended several pre-work briefings, and found them to be excellent. Special mockups, tools, and pre-training sessions were held to minimize the radiation exposure to personnel.- As a result, the licensee was able to satisfactorily reduce the expected overall personnel radiation exposure for the jo The mechanics removed, inspected and cleaned each of the hydraulic control valves. The inspector found that mechanics were well prepared to perform the planned evolutions, and diligent. All expected work, including replacement of the mechanicalinterlock cable, was completed satisfactoril Conclusions The inspector concluded that all personnel performance was good for the troubleshooting of the personnel access hatch hydraulic control valves and replacement of the mechanical interlock cable. Excellent briefings were observed,-

and mechanics were well prepared to perform the planned evolutions, and were diligent in their activitie M1.2 Soarkina of "B" Emeroencv Diesel Generator Rotor Shaft Brushes Durina Surveillance Testino On April 15, during a monthly "B" emergency ' diesel generator (EDG) surveillance

,

test, the licensee observed minor sparking on two (2) of the four (4) EDG rotor shaft h brushes. Surveillance acceptance criteria specified that a minor amount of sparking was acceptable. The inspector observed the surveillance activities and noted that

.. the licensee had implemented an aggressive inspection criteria for detecting sparking brushes. In addition, upon identification, the licensee promptly evaluated the condition, determined that operability of the EDG was not affected, and concluded l

< -5 , that the proper course of action was to replace the affected brushes. The inspector concluded that the licensee's actions were appropriate.

L jr

!#

<

h

.

M1.3 Refurbishment of Safety Related 125 Volt DC Breaker Insoection Scone On April 8, the licensee refurbished a safety-related, low voltage ABB, K-line type breaker (mar'ufactured by ABB Services Inc.). The inspector observed portions of the refurbishment and interviewed applicable personnel. In addition, the inspector evaluated the licensee's response to a broken secondary disconnect guide pin, which was identified by the inspector on April 17, during observation of the breaker post-maintenance testing, Observations and Findinas At Seabrook, safety related breakera are refurbished every 12-years, and are functionally tested every five (5) years. The subject breaker had been in operation since original installation and was being refurbished for the first time. The breaker serviced the 11 A safety battery since it's last functional test; and, following (refurbishment, was scheduled to be installed to service the 118 safety batter Refurbishment involves a complete disassembly, inspection, clean-up and reassembly of all major breaker component The inspector found that the electrical technicians were knowledgeable and exercised good control and parts inventory techniques during disassembly. The ,

'

technicians properly used the required procedure, demonstrated good communication practices and were detailed in their activities and subsequent 3 testin l l

During the post-maintenance testing, the inspector identified a broken secondary disconnect guide pin. The technicians immediately evaluated the condition, notified the system engineer and their supervisor, and initiated an Adverse Condition Report (ACR). The system engineer inspected the component and determined that although operability of the beaker was not affected, it was prudent to replace the affected disconnect mechanism. Following this repair, the breaker was tested satisfactoril Conclusions The inspector found that Seabrook's electricians performed well, during a first-time evolution to fully refurbish a safety battery breake M1.4 Pressurizer Gas Soace Samole / Vent Valve Position Indication Failure insoection Scoce i

! On May 4, during surveillance testing of the inside containment pressurizer gas L space sample line isolation valve RC-FV-2830, the licensee identified the loss of l position indication, and declared the valve inoperable as directed per technical

. _ _ _ _ _ _ _ _ _ _ -

-- ._ - _ _ - - - - - _ - _ - - _ _ - - _ _ - - _ _ - _ _ .

.

..

specification (TS) Section 3.6.3. The inspector reviewed these activities and

' evaluated the licensee's response to this issu Observations and Findings Valve RC-FV-2830, is a % inch solenoid operated valve used to periodically sample i: .the pressurizer gas space. This line is also used to vent gases from the pressurizer-as needed to prevent buildup of a hard bubble in the pressurizer. The licensee promptly isolated the penetration as directed per the TS, by closing the outside containment isolation valve RC-V-2840. Inspection of the valve internals revealed -~

that 6 of the 20 screws in the valve's electrical cable terminal board had separate A team was quickly formed by the licensee to determine the Root Cause and to

. provide required corrective actions to prevent recurrence. The licensee concluded that the valve is a fail safe valve and it's operation was not affected by the "as found" condition. The licensee's final root cause analysis for the screw (s) failure is ongoing. However, the licensee has preliminarily determined that the failed screws were not the cause for the loss of valve position indication. . That problem was attributed to temperature effect on the associated magnet, which can cause the switch not to change state. The licensee implemented a vendor recommendation to use a more sensitive switch to address this issue. Post-maintenance tests proved '

satisfactory valve position indicatio Conclusions The inspector concluded that the licensee responded well to this event. Adequate briefings and followups were observed. The licensee promptly initiated an investigation for the failed pressurizer sample valve position indication, and implemented corrective actions. The inspector had no further question M8 Miscellaneous Maintenance issues (92902)

M8.1 - (Closed) Violation 50-443/97-03-02: burst tubing as a result of using inadequate pressure rated tubing during emergency core cooling system (ECCS) valve testin I Inspection Report 97-03 identified several cases of incorrect tubing installation by the l&C department which revealed a significant weakness in the licensee's corrective action program. The inspector verified the corrective actions described in the licensee's response letter, dated August 29,1997, to be reasonable and

. complete. Among the corrective actions verified were: l&C department guidance ]

'

developed to ensure that only high pressure rating tubing is used for connections to inservice components; training of the individuals involved; site discussions on the event and associated root cause; continued implementation and development of the human error reduction technology and reinforcement of error reduction techniques;

~

and the establishment nf a new organization, led by the corrective action program  ;

manager, to implement the corrective action program using the Pil technology. No .l similar problems have been identified since the implementation of the cormctive actions. This violation is closed.

K u

'

)

- __________=_____A

.

.

7~

< ' M8.2 (Closed). Violation 50-443/97-06-05: This violation involved two examples of failure to follow maintenance procedures including the lifting of electrical leads, and the improper substitution of a replacement springs in safety-related check valves. The inspector reviewed Seabrook's corrective actions for this violation which included:

coaching and training of personnel, a revision to procedure MA 3.0, " Work Control Practices" to clarify the expected actions of engineering personnel, and verification that all other potentially affected components had the proper spring installed. The inspector found that the licensee's actions were reasonable and complete. This violation is close M8.3 (Closed) LER 50-443/98-03: improper substitution of battery performance testing for battery service testing. The inspector performed an in-office review of this event which discussed three examples between 1990 to 1995.where battery performance testing had been substituted for battery service testing more than once in a sixty month period as allowed by Technical Specification (TS) surveillance requirement 4.8.2.1e.. This resulted in instances where battery service testing was not performed every eighteen months as required by TS surveillance requirement 4.8.2.1 The licensee attributed the root cause for this failure to an inadequate review of the

. surveillance requirements when developing the testing schedule. The corrective actions for this event included: training of personnel, clarification of the applicable procedures, and a plan to revise the surveillance requirements. The inspector concluded that the significance of this event was minimal as highlighted by the fact that the batteries passed all subsequent service tests. This failure to conduct the battery service testing at the required periods constitutes a violation of minor significance and is not subject to formal enforcement actio Ill. Engineering E2 Engineering Support of Facilities and Equipment E Emeroencv Diesel Generator Exhaust Pine Inanection Scone On April 1, during a monthly surveillance test of the "A" emergency diesel generator (EDG), the inspector identified steam and water coming out of tiie EDG exhaust piping insulation. The inspector notified the system engineer and questioned the impact the this condition may have on the EDG operation. The inspector noted that the licensee had recently identified, on March 4,1998, the possibility of internal corrosion on the EDG's exhaust piping due to rain water entering the pipe past the

< protective exhaust hood cap. .This condition was self disclosed by debris exiting the EDG exhaust piping. .The inspector met with the system engineer, reviewed applicable documentation, and evaluated the licensee's response to this issue.

V p

t

'? .

. .I

. e

.

b.- Observations and Findings The EDG combur. tion air intake and exhaust system is required to supply adequate

' combustion ' air and dispose of resultant exhaust products to support EDG operatio The exhaust portion consists of a safety-related, carbon steel,40 inch diameter

. pipe, operating in a temperature environment of 900 to 1000* F.

!.

! Technical Specification (TS), Section 4.8.1.1.2, requires the exhaust pipe lagging be

'

inspected for leakage every 31 days. This requirement is accomplished via surveillance procedure OX1426.01. The inspector noted a minor weakness in that -

' the operator did not identify and question the pipe condition. Upon notification by the. inspector, the system engineer promptly performed a field walkdown, and

< l initiated an adverse condition report (ACR) to evaluate this conditio The licensee determined that no thru wallleak existed, and attributed the steam water mixture to heating of wetted lagging caused by rain water leakage through

'

the roof. Two exhaust line sample points were selected and ultrasonically teste .

The data and subsequent evaluation were documented in an operability determination, which concluded that the EDG exhaust piping was operabl The inspector reviewed these documents and found them to be adequate. The

- present condition was evaluated by the licensee as not an immediate concern,

_however, the inspector noted some potential weaknesses in the licensee's methods for evaluating the long-term exhaust line reliability. These included:

-= . Currently, the operators perform weekly draining of the EDG exhaust pipe per l surveillance procedure OS1426.12. However, the line is not drained following periods of heavy rain. Therefore, rain water could remain inside the pipe for a full week prior to being drained, thereby potentially increasing the effects of erosion / corrosio +^ The licensee performed a base line UT inspection in 1991, and a subsequent UT in 1996, as required. This UT identified a thinning area which was evaluated to be acceptable, and a new inspection was scheduled to be performed in 1999, at the end of Cycle 6. However, the inspector noted lthat due to interference with a pipe support, the UT did not include all of the area of the exhaust pipe elbow which was identified by the licensee as

. having the highest potential for erosion / corrosio * The licensee did have provisions to repair the roof leaks during this summer L to prevent wetting of the insulation and reducing the potential for external corrosion.' However, the inspector noted, that the licensee did not have any

planned corrective actions to prevent the intrusion of rain water into the EDG

< ) exhaust piping,'via the exhaust hood cap, to reduce the effects of internal corrosion / erosion.-

,

,

-

( *'

..)

.

t 9 Conclusions

. The licensee promptly and adequately determined that no degradation of the EDG exhaust piping existed. However, the inspector noted some weakness in the licensee's method to evaluate the long-term reliability of the subject piping. The licensee has initiated an adverse condition report (ACR) to review these issue E2.2 . '2B Coolant Charaina Pumo Drive Pin and Bushina a; Insoection Scope The inspector reviewed the system engineering support provided to resolve an issue-involving a worn drive pin and bushing on the 2A coolant charging pump shaft-driven lubricating oil pump. The drive pin and bushing were inspected as part of a routine maintenance inspection and the licensee elected to replace these components after the planned inspection identified wea b. ' Observations and Findinas The inspector discussed this issue with the system engineer who indicated that the

-

drive pin / bushing had been installed during design change request (DCR) 95-04 ;The affected components were designed to be replaced periodically based on the inspection results. The system engineer concluded that the drive pin and bushing

- were operable at the time of the inspection, but replaced these components to ensure future reliability. The inspector looked at the pin and bushing and concluded that the licensee's actions were appropriat Conclusions

- The system engineer provided good support and analysis of a degraded charging pump drive pinibushing. The licensee's actions to replace the components and continue with the inspection program were appropriat E2.3 Lead /Laa Circuit Card Testina Insoection Scope

.The inspector' reviewed the licensee's follow-up to issues identified involving the calibration of the lead / lag control circuit (NLL) cards. Licensee engineers identified

. questions regarding the NLL card calibration methodology while investigating the

.steamline pressure channel calibration event discussed in Section 0 . Observations and Findings

'

As discussed in Section 04.1, the NLL cards are used in several safety-related circuits including the steamline pressure and the overpower /overtemperature delta temperature (DELTA T) channels. _ The NLL cards ensure that the applicable

.c -

_

.

,

,

- protective system response leads the process variable input. Seabrook engineers

identified questions regarding the method used to determine the NLL card lead (T1)

and lag (T2) time constant .The NLL card time constants were determined by measuring and analyzing the card output voltage response versus time following a step input voltage change. The output voltage response was graphically recorded and analyzed to determine the T2

_

value. The T1 value was then analytically determined based on the T2 value and the ratio between the peak and input voltage Prior to the investigation, Seabrook determined the T2 value by measuring the time difference between the initial voltage peak and the voltage level corresponding to approximately 36% of the difference between the initial peak and the final steady state voltage. Seabrook noted, following NLL card bench top testing, that this method would be expected to introduce some error since the initial portion of the output response curve is characteristic of a second order time constant curve rather than the assumed exponential decay curve. The error would tend to produce a higher indicated T2 constant (conservative direction), resulting in a longer calculated T1 constant (non-conservative direction).

Seabrook discussed the test method question with the NLL card vendor (Westinghouse). Seabrook engineers noted, and the vendor engineers concurred, that the measured time constants would be more conservative if they were

' determined ur.ing the data on the exponential portion of the output voltage curv Seabrook questioned whether the non-conservative error introduced by the initial data analysis method would result in any of the NLL cards not meeting the TS time constant limits. The bench test results indicated that the time constants for the DELTA T cards were closest to a TS operability limi Seabrook sent the output voltage data for one DELTA-T card to the vendor for analysis. The vendor independently determined that the card met all TS limit ' Seabrook reviewed this information and concluded that the error introduced by the initial test method would not result in any TS limits being exceeded. Although not an operability concern, Seabrook recalibrates the DELTA-T channels using the new methodology, and initiated a work request to calibrate the steamline pressure channels using the more conservative metho Seabrook obtained additional data and has continued to work with the vendor to -

L better understand the potentialimpact of the initial calibration method. The )

f inspector noted that the licensee's operability determination was based on vendor l'

review of the data for one channel and questioned whether the operability determination could be applied generically to all channels calibrated by this metho ' The inspector does not consider this issue a current operability concern since the

DELTA-T channels have been calibrated using the more conservative method. The

!. Issue of whether the initial calibration method was adequate will remain unresolved

.

pending further investigation. (URI 98-02-01)

.i ll _ - _ _ _ _ - _ - - _ _ _ _

.

e ,

-

,.

,

11 Conclusions The licensee performed well by identifying and. investigating questions pertaining to their previous. lead / leg card calibration methodology. This issue will remain unresolved pending review of the impact of the initial method on the channel operabilit E8- L Miscellaneous Engineering issues E (Closed) LER 50-443/98-02-00: Potential safety injection (SI) pump runout condition. The licensee reported that the Si system had been operated in a configuration that could have resulted, given several design basis assumptions, in exceeding the "A" Si pump runout limits. The licensee subsequently determined

- that the initial' analysis did not consider that the Si system test header piping downstream of valve SI-V-131 was seismically capable. This information was incorporated into a revised analysis and the licensee concluded that the Si system

- configuration would not have resulted in exceeding any SI pump runout limits. The licensee subsequently retracted the event report. The inspector reviewed this event and concluded that the event retraction was appropriat l E8.2 ~ (Closed) LER 50-443/97 02-01: Containment penetration piping overpressure potential. The licensee identified the potential for overpressurization of several containment isolation valves due to the heatup of trapped fluid in the line connected

- to the inside containment isolation valve. .This condition was identified in response to NRC Generic Letter 96-06. The licensee's short-term actions were to vent the affected lines to the containment sump. The long-term corrective action was to install a relief valve in each line. The inspector performed an in-office review of this event and concluded that the licensee's actions were acceptabl . E8.3 (Closed) LER 50-443/97-018-00, and 97-018-01: Non-conservative anticipated transient without scram (ATWS) mitigation system setpoint. The licensee reported, as discussed in NRC Inspection Report 97-07, that the ATWS mitigation system

^

,

actuation ~setpoint was based on 40% turbine versus 40% reactor power. A subsequent analysis determined that the system actuation was not required until 50% reactor power. The licensee concluded that the initial system design was adequate, and within the design basis, and retracted the event report. The

! '

inspector performed an in-office review of this event and concluded that the L licensee had an adequate basis for retracting the event report.

l~

h E8.4 (Cloned) Violation 50-443/97-04-02: failure to revise two safety related procedures, to incorporate the new Cycle 6 boron concentrations required to be injected in the

. event that more than one control rod failed to fully insert into the reactor core

!

during a reactor trip. : The inspector verified the corrective actions described in the licensee's response letter, dated October .23,1997, to be reasonable and complet .

. Among the corrective actions verified were: revision to procedures ES-0.1 and

• : OS1202.04, to require use of Figure RE-18 for obtaining the correct boron-

.

concentration values; verification of the review performed by Seabrook personnel to o

i 3 ._

l

'

+

'

.m __ ____.i__________ _ _ . . _ . _

, .

.

.

.. determine whether any other documentation was affected by the implementation of the Cycle 6 core design; revision of the basis for setpoint ID A25 in the Seabrook Setpoint Study to reference the value of Figure RE-18; and verification of the

checklist developed by Seabrook for future core reload DCR's to assist in the

.. identification of variables that will require revie Although no similar problems were identified, the inspector'noted that on April 2,

.1998, the licensee identified a failure to update Figure RE-19, to reflect updated rod insertion limit (RIL) information. The licensee evaluated this condition and concluded that use of the incorrect RE-19 could have lead to a non-conservative shutdown

' margin determination for stuck rod calculations below 50 % power, however, sufficient excess shutdown margin existed to offset any non-conservatism. The inspector verified that the specified shutdown margin limit was met, and noted that the licensee's attributed this failure to revise RE-19 to a human performance

' deficiency. The inspector concluded that the failure to revise the RE-19 procedure was not indicative of a programmatic problem and concluded that this was a violation of minor significance and not subject to formal enforcement actio Therefore, violation 50-443/97-04 02 is close IV. Plant Sunnart

'R1 Radiological Protection and Chemistry Controls R1.1 General Comments (71750)

During the period the inspectors frequently toured the radiologically controlled area (RCA) and observt J radiological controls practices. The radiological controls technicians were observed to be attentive and provided high quality assistance to plant workers. Plant workers were observed to be following proper radiological work practices including use of dosimetry and protective equipment. Personnel briefings conducted prior to containment entries were thorough and informativ Conduct of Security and Safeguards Activities S1.1 General Comment (71707. 71750)

The inspectors observed security force performance during inspection activities.

f Protected area access controls were found to be properly implemented during random observations. Proper escort control of visitors was observed. Security officers were alert and attentive to their duties.

b c

______-______L_--_______-

- - _ _ _ - _ - - _ _ - _ _ _ _ _ _ _ - - _ _ _ - - _ _ - _ - _ _ _ _ - _ _ - _ _ _ _ _ _ - _ _ _ - _ _ _ - _ - _ _ _ _ _ - _ _ _ _ - - _ _ - _ , _ _ - - - - _ _ _ _ - _ _ _ _ _ _ _ _ _ - _ - _

.

.

V. Management Meetings X1 Exit Meeting Summary The inspectors presented the inspection results to members of licensee management, following the conclusion of the inspection period, on May 22,199 The licensee acknowledged the findings presente l

)

g ,

- - - - - _ - . _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ , _ _ _ _ _ _ _ _ _

r

.

.

PARTIAL LIST OF PERSONS CONTACTED Licensee W. Diprofio, Unit Director J. Grillo, Technical Support Manager l

R. White, Design Engineering Manager J. Peterson, Maintenance Manager G. StPierre, Operations Manager B. Seymour, Security Manager J. Linville, Chemistry and Health Physics Manager HilC Craig Smith, Project Manager INSPECTION PROCEDURES USED IP 37551: Onsite Engineering IP 61726: Surveillance Observation IP 62707: Maintenance Observation IP 71707: Plant Operations IP 71750: Plant Support Activities IP 92700: Onsite Followup of Written Reports of Nonroutine Events at Power Reactor Facilities IP 92902: Followup - Engineering IP 92903: Followup - Maintenance IP 93702: Prompt Onsite Response to Events at Operating Power Reactors ITEMS OPENED, CLOSED, AND DISCUSSED Ooened Unresolved item, 98-02-01, Performance Deficiencies During NLL Card Calibrations

. Closed:

LER 98-03-00, Class 1E 125 VDC Battery Surveillance Testing LER 98-02-00, and 98-02-01; Potential Safety injection Pump Runout Condition LER 97-016-00, and 97-016-00; Non-Conservative AMSAC Arming Setpoint LER 97-02-00; Containment Penetration Piping Overpressure Potential IFl 97-03-01; Inadvertent Steam Generator Drainings VIO 97-03-02; Burst Tubing Event VIO 97-06-05: Failure to Follow Maintenance Procedures

- VIO 97-04-02; Failure to Revise Two Safety Related Procedures VIO 97-06-04; improper Parts Substitution, (This issue was initially opened due to an administrative oversight and is closed)-

,

,---._ _ - - - - _ _ - - - _ - . - _ - - . - - _ _ - - _ - - - - - . - - - - _ _ - - _ _ . _ - - - - - - .

..

.

LIST OF ACRONYMS USED ACR Adverse Condition Report ASME' American Society of Mechanical Engineers CAS Central Alarm Station CBS Containment Building Spray EDG Emergency Diesel Generator EFW Emergency Feedwater FME Foreign Material Exclusion -

gpd gallons per day gpm gallons per minute LCO Limiting Condition for Operation MOV motor operated valve

.MPCS Main Plant Computer System NSARC Nuclear Safety and Audit Review Committee NSARC OS NSARC Operations Subcommittee psig pounds per square inch gauge OC - Quality Control

' RHR Residual Heat Removal SG eteam generator SIR Station Information Report SORC Station Operations Review Committee SUFP Startup Feedwater Pump SW Service Water TDEFW Turbine Driven Emergency Feedwater Pump TS Technical Specifications UFSAR Updated Final Safety Analysis Report WR work request i

.

l i

i I

'

.