IR 05000269/1987014
| ML16161A815 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 05/11/1987 |
| From: | Bernhard P, Jape F, Mathis J, Matt Thomas NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML16161A814 | List: |
| References | |
| 50-269-87-14, 50-270-87-14, 50-287-87-14, NUDOCS 8705280300 | |
| Download: ML16161A815 (4) | |
Text
REG(,,UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTA STREET, N.W., SUITE 2900 ATLANTA, GEORGIA 30323 Report Nos.:
50-269/87-14, 50-270/87-14, and 50-287/87-14 Licensee:
Duke Power Company 422 South Church Street Charlotte, NC 28242 Docket Nos.: 50-269, 50-270, License Nos.: DPR-38, DPR-47, and and 50-287 DPR-55 Facility Name:
Oconee 1, 2, and 3 Inspection Conducted:
April 2-3, 1987 Inspectors: to
_5-//-7 ernhar Date Signed J. L. Mathis Date Signed
M. Thomas Date Signed Approved by:
Chi///&.
'
F. Jape, Chi f, Test Program Sec ion Date Signed Engineering Branch Division of Reactor Safety SUMMARY Scope:
This special unannounced inspection was conducted in the areas of low pressure service water (LPSW)
system fouling problems and related corrective action Results:
No violations or deviations were identifie PDR ADOCK 05000269 G
REPORT DETAILS 1. Persons Contacted Licensee Employees
- R. T. Bond, Performance Engineer
- J. M. Davis, Technical Services Superintendent
- C. L. Harlin, Compliance Engineer
- F. E. Owens, Regulatory Compliance
- R. L. Sweigart, Operations Superintendent
- M. S. Tuckman, Plant Manager Other licensee employees contacted included engineers, technicians, operators, mechanics, security force members, and maintenance personne NRC Resident Inspector J. C. Bryant, Senior Resident Inspector, Operations
- Attended exit interview 2. Exit Interview The inspection scope and findings were summarized on April 3, 1987, with those persons indicated in paragraph 1 above. The inspectors described the areas inspected and discussed in detail the inspection finding No dissenting comments were received from the license The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspectors during this inspectio.
Licensee Action on Previous Enforcement Matters This subject was not addressed in the inspectio. Unresolved Items Unresolved items were not identified during this inspectio. Low Pressure Service Water System Fouling The purpose of this inspection was to review licensee corrective actions and observe cleaning activities of the low pressure service water (LPSW)
system, low pressure injection (LPI) coolers, and reactor building cooling units (RBCUs).
The licensee stated that test results indicated that the performance of the LPI coolers and RBCUs had degraded from their original design capacitie The licensee attributed the degraded performance to fouling in the coolers due to the raw lake water utilized by the LPSW
syste Due to the fouling of the LPI coolers and RBCUs, Units 1 and 2 were being operated at reduced power levels. Unit 3 was in the process of restarting from a refueling outage, but it was decided to clean the Unit 3 LPI coolers and RBCUs prior to returning Unit 3 to powe Specific areas examined during this inspection included abnormal operating procedures for the LPI system; surveillance procedures for the LPI coolers and RBCUs; and cleaning of the RBCUs. These areas are discussed belo a. Abnormal Operating Procedures As a result of the fouling problems, the licensee performed an evaluation of the operability of the LPI coolers and RBCUs and developed a justification for continued operation (JCO)
of Units 1 and 2. Unit 3 restart from a refueling outage was delayed to complete cleaning of the Unit 3 LPI coolers and RBCU The JCOs discussed operator actions which are required to be performed in the event that a single failure results in the loss of the most effective LPI coole The inspectors reviewed abnormal operating procedures AP/1/A/1700/07, AP/2/A/1700/07, AP/3/A/1700/07, Loss of Low Pressure Injection System, for Units 1, 2, and 3, respectivel The procedures for Units 1 and 2 were revised March 31, 1987, and the procedure for Unit 3 was revised March 27, 198 The procedures were reviewed to verify that provisions were included to increase LPSW flow (from 3000 gpm nominal to 5400 gpm) to the operable LPI cooler following a loss of coolant accident if one cooler is inoperable, and to align a second LPI pump to the operable LPI coole The inspectors also performed a walk through of the above procedural actions with operations personne These actions are performed from the main control roo b. Surveillance Procedures A review was performed of the procedures used to gather data to determine the heat exchangers heat transfer coefficient The procedures reviewed were PT/O/A/0160/06 Revision 0, "Reactor Building Cooling Units Heat Exchanger Performance" and PT/0/A/0251/18, Revision 0, "Decay Heat Cooler Test."
Test procedure PT/0/A/0160/06 used permanently installed flow instrumentation and temperature instruments, where availabl Resistance temperature detectors (RTDs)
were used for temperatures for which permanent plant instruments were not available. A 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> soak period was used to let conditions stabilize after changes in system configuration prior to data being take The procedure was used for taking data only. The Engineering Evaluation was performed by the licensee's design engineering personnel at the corporate office and the results transmitted to the sit The test is to be performed each refueling or as needed. Test procedure PT/0/A/0251/18
required all temperatures and the LPSW side differential pressure across the decay heat cooler to be measured by test equipmen Flow through the heat exchanger was measured using permanent plant instrumentatio As this system uses a water to water heat exchanger, a 15 minutes soak period was used prior to data being take Data were taken at five minutes intervals for a minimum of one hou An engineering evaluation of the data is performed by design engineering personnel and is not part of this test. The test is required each refueling outage or as neede The inspectors did not review the licensee's engineering analyses, as this function was not performed on site. The inspectors will review the engineering analyses during a followup inspectio c. Maintenance Observation The inspectors observed cleaning activities for Unit 3 Reactor Building Cooling Units (RBCUs) at the OconeeFacility. Instruction for back flushing coils, rodding out tubes and visually inspecting coils prior to and following cleaning were described in procedure TM/3/A/1100/08. The inspector reviewed the procedure to ensure that administrative approval was obtained before initiating the work. In addition, the inspector verified that limiting conditions of opera tion were met while the component was removed from service and that the personnel performing the cleaning activity were qualifie The cleaning process of the RBCUs consisted of back flushing within a closed-loop thereby making it difficult to see the crud that was backflushed from the syste The RBCUs are supplied by individual lines from the separate LPSW supply header Prior to cleaning both the supply and return headers were isolated in accordance with procedure MP/O/A/1800/ Upon removal of accessible cleaning plugs, a video inspection was performed prior to cleaning RBCU coil Back flushing and chemical cleaning consisted of opening chemical addition valves and adding Trisodium Phosphate (TSP)
as directed by the accountable enginee The licensee allowed the TSP to remain stagnant for approximately two (2)
hours before the backflushing started. Demineralized water was used in the backflushing proces Backflushing was performed for approximately 30 minutes under the direction of the accountable enginee Following the backflushing process a final inspection of the RBCUs coils was performe The accountable engineer made a determination as to whether further cleaning and backflushing was necessary. The cleaning process appeared to be effective in removing crud from the coils, however, not until performance tests are perform will the licensee know how effective the cleaning process increases efficiency of the coils. The testing had not been completed prior to the conclusion of this inspectio The inspector will review the test results at a later inspectio No violations or deviations were identified in the area inspected.