SERIAL:HNP-02-052
10CFR50.54(f) United States Nuclear Regulatory Commission
ATTENTION: Document Control Desk
Washington, DC 20555搬家要注意什么
SHEARON HARRIS NUCLEAR POWER PLANT
DOCKET NO. 50-400/LICENSE NO. NPF-63
15-DAY RESPONSE TO NRC BULLETIN 2002-01, REACTOR PRESSURE VESSEL HEAD DEGRADATION AND REACTOR COOLANT PRESSURE BOUNDARY INTEGRITY
Dear Sir or Madam:
By the letter dated March 18, 2002, the U. S. Nuclear Regulatory Commission (NRC) issued NRC Bulletin 2002-01, “Reactor Pressure Vesl Head Degradation and Reactor Coolant Pressure Boundary Integrity”. The Bulletin directs addres to submit: (1) information related to the integrity of
the reactor coolant pressure boundary including the reactor pressure vesl head and the extent to which inspections have been undertaken to satisfy applicable regulatory requirements, and (2) the basis for concluding that plants satisfy applicable regulatory requirements related to the structural integrity of the reactor coolant pressure boundary and future inspections will ensure continued compliance with applicable regulatory requirements, and (3) a written respon to the NRC in accordance with the provisions of Title 10, Section 50.54(f), of the Code of Federal Regulations (10 CFR 50.54(f)) if they are unable to provide the information or they cannot meet the requested completion dates.
Enclosure 1 to this letter provides Carolina Power & Light Company’s (CP&L) respon to this Bulletin for the Harris Nuclear Plant (HNP). The Harris Nuclear Plant respon to the bulletin provides reasonable assurance that plant inspection and maintenance programs are adequate to prevent degradation as obrved at the Davis-Bes Plant. Harris Nuclear Plant is considered to be in the NRC category of plants with low susceptibility (greater than 30 effective full power years of operation relative to Oconee 3).In addition, HNP has not previously identified either leakage from or cracking in Vesl Head Penetration (VHP) nozzles.
HNP-02-052/ Page 2
早上起来恶心干呕>肚子疼便血Plea refer any questions regarding this submittal to Mr. John Caves at (919) 362-3137.
Sincerely,
RTG/rtg
Enclosure
James Scarola, having been first duly sworn, did depo and say that the information contained herein is true and correct to the best of his information, knowledge and belief, and the sources of his information are employees, contractors, and agents of Carolina Power & Light Company.
________________________________
Notary (Seal)
excel乘法函数My commission expires:
c: Mr. J. B. Brady, NRC Sr. Resident Inspector
项目运营方案
Mr. Mel Fry, Director, N.C. DENR
Mr. J. M. Goshen, NRC Project Manager
Mr. L. A. Reyes, NRC Regional Administrator
HNP-02-052/ Page 3
SHEARON HARRIS NUCLEAR POWER PLANT
NRC DOCKET NO. 50-400/LICENSE NO. NPF-63
15-DAY RESPONSE TO NRC BULLETIN 2002-01, REACTOR PRESSURE VESSEL HEAD DEGRADATION AND REACTOR COOLANT PRESSURE BOUNDARY INTEGRITY The Harris Nuclear Plant, HNP, was licend for commercial operation in 1987, at about the same time as the nuclear industry’s awareness was heightened regarding the concerns addresd in NRC Generic Letter 88-05, “Boric Acid Corrosion of Carbon Steel Reactor Boundary Components in PWR Plants”. HNP committed to the establishment of a formal program governing the control of boric acid corrosion in respon to NRC Generic Letter 88-05 provided by CP&L, dated May 27, 1988, rial number NLS-88-110. Inspections of susceptible components are directed by a program, which is described in Plant Programs procedure PLP-600, “Boron Corrosion Program”. PLP-600 states that t
初中生自我陈述he boron corrosion program has been implemented at HNP to “prevent boric acid attack of pressure boundary components and equipment important to safety.” The program is bad on identifying, evaluating, and repairing borated water leaks and the effects of the leaks from all sources that could result in a boric acid corrosion problem. This approach includes the u of high standards for cleanliness to leave the metal clean of corrosives including the cleaning of the affected components, and using the appropriate process and qualified people to execute the program.
The Harris Nuclear Plant has been analyzed for susceptibility relative to Oconee 3 using the time-at-temperature model and plant-specific input data reported in EPRI’s Material Reliability Project, MRP-2001-48. This evaluation showed that it would take HNP 115.5 effective full power years (EFPY) of additional operation from March 1, 2001, to reach the same time at temperature as Oconee 3 at the time that leaking nozzles were discovered in March 2001. Harris Nuclear Plant falls into the NRC category of plants with low susceptibility (greater than 30 effective full power years of operation relative to Oconee 3).
The following ctions include the HNP respons to the specific items as required by NRC Bulletin 2002-01:
NRC Item 1.A:
Provide a summary of the reactor pressure vesl head inspection and maintenance programs that have been implemented at your plant.
HNP Respon for Item 1.A:
The Harris Nuclear Plant has two principle elements to the overall boron corrosion program for inspection, documentation, and resolution of borated water leaks or boric acid build-up on the reactor pressure vesl, RPV, head. They are PLP-600 (described above) and Engineering Surveillance Test procedure EST-227 (ASME Section XI Class 1 System Pressure Test).
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The purpo of PLP-600 is to address the concerns identified in Generic Letter 88-05. This program is bad on walkdown inspections during shutdown outages, inspection during maintenance activities, trending the daily reactor coolant system leakage evaluations, and monitoring for leakage during power operations.
吃了螃蟹不能吃什么Three plant procedures implement PLP-600 requirements. Operations Periodic Test procedure (OPT-1519) requires a visual inspection of the pressure boundary components inside containment building prior to cooldown for every Refueling Outage (RFO). Corrective Maintenance procedure (CM-M0070) requires inspection of the Control Rod Drive Mechanism (CRDM) area for any evidence
of leakage. Operations Surveillance Test procedure (OST-1026) provides for a daily reactor coolant system evaluation for leakage. Corrective actions are taken to repair any identified borated water leakage in accordance with Work Package Planning procedure (WCM-002) and ASME Section XI requirements. Incidents of borated water leakage onto the reactor vesl head are documented in the Corrective Action Program.
In light of recent industry events, a bare metal visual examination was performed on the accessible portion of the Reactor Pressure Vesl (RPV) head and CRDM penetrations. Qualified Visual Testing (VT-2) examiners using approved plant procedures performed the examinations. The VT-2 examiners had been provided specific training regarding CRDM leakage. This training followed the training guideline, “Visual Examination for Leakage of Reactor Head Penetrations On Top Of Head” provided by Electric Power Rearch Institute (EPRI). The inspections of the “uphill” portions of the CRDM penetrations were limited to what could be en from below and from the side. A circular area approximately 3 feet in diameter was not readily accessible for direct visual examination without the u of special tools or insulation removal. A 100% bare metal inspection has not been conducted at HNP. However, during RFO-10 approximately 85% of the reactor vesl head penetration nozzles were examined.
The purpo of EST-227 is to fulfill the pressure test requirements for Class 1 pressure retaining components (including RPV head penetrations) in accordance with the 1989 Edition of ASME Boiler and Pressure Vesl Code Section XI. The acceptance criteria and inspection requirements of ASME XI code are ud to disposition any relevant indications. EST-227 is performed at the end of every refueling outage.
NRC Item 1.B:
Provide an evaluation of the ability of your inspection and maintenance programs to identify degradation of the reactor pressure vesl head including, thinning, pitting, or other forms of degradation such as the degradation of the reactor pressure vesl head obrved at Davis-Bes.
HNP Respon for Item 1.B:
The HNP programs and procedures for RPV head inspection and maintenance, as summarized in Item 1A above, are appropriate and provide assurance that degradation of the RPV head, including thinning, pitting, or other forms of degradation, will be identified and corrected.
Plant procedures and surveillances, summarized in 1A above, prescribe the actions necessary to bot
h inspect and disposition borated water system leakage and any resultant corrosion of primary pressure boundary components. The procedures and surveillances, which include the programmatic implementation of NRC Generic Letter 88-05 via PLP-600, provide a framework for the systematic monitoring of locations where boric acid leakage could occur, and measures to prevent the degradation of the RCS pressure boundary by boric acid corrosion.
Certified VT-2 personnel using qualified plant procedures perform the visual inspections. Inspection of the RPV head, including the CRDMs and mechanical connections, are specific inspection items identified in EST-227 and CM-M0070. Any evidence of boric acid leakage (active or inactive) found during inspections, operator/system engineer walkdowns, or maintenance activities require evaluation. The evaluation consists of the following:
A. Identifying the source of leakage
B. Determining if leakage is active or inactive (with nsitivity to the leakage around
CRDM penetrations)
C. Decontaminating (removing & cleaning) the boron.
D. Inspecting the component to identify degradation. If degradation is found, additional
examinations (surface or volumetric) may be necessary to quantify the extent of damage. The adequacy of the inspection and maintenance programs is evidenced by successful detection of evidence of leakage during RFO-08 (10/98-11/98) and RFO-10 (09/01-01/02) as described in Item 1C.
