ML030850136
| ML030850136 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 04/23/2003 |
| From: | Vissing G NRC/NRR/DLPM/LPD1 |
| To: | |
| Vissing G, NRR/DLPM, 415-1441 | |
| References | |
| TAC MB7609 | |
| Download: ML030850136 (6) | |
Text
April 23, 2003 LICENSEE:
Calvert Cliffs Nuclear Power Plant, Inc.
FACILITY:
Calvert Cliffs Nuclear Power Plant, Unit No. 2
SUBJECT:
SUMMARY
OF MARCH 18, 2003, CATEGORY 1 MEETING WITH CALVERT CLIFFS NUCLEAR POWER PLANT, INC. TO DISCUSS THE LICENSEES ONGOING UNIT NO. 2 REACTOR PRESSURE VESSEL HEAD INSPECTION AS REQUIRED BY THE ORDER DATED FEBRUARY 11, 2003 (TAC NO. MB7609)
On March 18, 2003, a public meeting was held between the U.S. Nuclear Regulatory Commission (NRC), and representatives of Calvert Cliffs Nuclear Power Plant, Inc. (CCNPPI or the licensee) at NRC Headquarters, One White Flint North, 11545 Rockville Pike, Rockville, MD. The purpose of the meeting was to discuss the ongoing inspection of the Calvert Cliffs Nuclear Power Plant, Unit No. 2 reactor pressure vessel (RPV) head. This inspection was in response to the NRC Order dated February 11, 2003.
The licensee presented information on their inspection results to date. They will continue the inspections during a second window of opportunity during the current refueling/steam generator replacement outage. The licensee has removed the insulation off of the RPV head and a 100%
bare metal visual inspection indicated no indications of cracks, leakage or boron deposits. The licensee has performed ultrasonic testing (UT) on 13 of 65 control element drive mechanism (CEDM) nozzles to date, with coverage results less than expected and less than required by the Order. The Order requires a 100% UT inspection of each nozzle. The licensee could not inspect 2 inches above the weld or 360 degrees around the nozzles in most cases. The clearance between the thermal guide sleeve and the nozzle did not, in all cases, allow complete access of the UT probes. In some cases, the guide sleeves were distorted such that there was insufficient clearance for insertion of the UT probes between the nozzles and thermal sleeves.
With a goal of inspecting every nozzle, the licensee is working on improving probe coverage with modifications to the probes. The licensee recognizes that they may need to remove the thermal guide sleeves since they may not be able to obtain 100% coverage in all cases, and reweld funnels onto the end of the CEDM nozzles. The licensee would like relief from the requirement of 360 degree coverage. However, the licensee could not get relief from 100% UT coverage and made it clear that the structural integrity of the CEDM nozzles was not the critical issue as much as meeting the requirements of the Order of 100% coverage. The licensee is looking at resolving the issue for operation only during the upcoming cycle. They are considering replacement of the RPV head some time in the future. With improvements in the inspection coverage, the licensees goal is to inspect every nozzle during the next window of opportunity in early April. Then they will make an assessment of the results. Compensatory measures have not been addressed yet. Another meeting with the NRC staff will be planned to provide information on the results of the inspections including the percentage of the area achieved above each weld, the results of the UT leak path assessment and drawings showing the actual geometry of the physical restriction in the nozzles that limits inspection coverage.
The meeting concluded with the identification of four issues that needed further discussion at a later time. Those issues include:
1.
Were the yield strengths of the reactor vessel nozzles that experienced primary water stress corrosion cracking higher or lower than the two heats at CCNPP?
2.
For the 13 penetrations inspected to date, what percentage of the area above the weld required by the Order has been covered?
3.
For the 13 penetrations inspected to date, explain the results of the UT leak path assessment.
4.
The staff requested a drawing that shows the actual geometry of the physical restriction in the nozzles that limits inspection coverage.
Subsequent to the meeting, the licensee provided additional information regarding these issues:
1.
The licensee identified that all CEDM cracking in Combustion Engineering plants has been in material with higher yield strengths than that at CCNPP. Cracks have been identified in plants from other vendors with yield strengths both higher and lower than that at CCNPP.
2.
The question is moot with the completion of inspections at CCNPP.
3.
During several discussions with the licensee and their inspection vendor, the analysis method for the leak path data, and in particular application to CCNPP data, was described to the NRC staff. These discussions included a description of the basis for misinterpretation of the data provided initially by the licensee that indicated limited coverage by this approach. The licensees inspection vendor stated that there was sufficient data to perform the leak path analysis for each nozzle.
4.
The licensee provided sketches that illustrate the step on the nozzle inside diameter that limits the annulus between the CEDM nozzles and the thermal guide sleeves.
Three members of the public were in attendance. is a list of the meeting attendees, and Enclosure 2 is a copy of the licensees slides presented at the meeting.
Please direct any inquiries to Guy S. Vissing, Senior Project Manager at 301-415-1441 or Allen Hiser, Jr., Technical Reviewer at 301-415-1034.
/RA/
Guy S. Vissing, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-318
Enclosures:
- 1. List of Attendees
- 2. Licensee Handouts cc w/encls: See next page Please direct any inquiries to Guy S. Vissing, Senior Project Manager at 301-415-1441 or Allen Hiser, Jr., Technical Reviewer at 301-415-1034.
/RA/
Guy S. Vissing, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-318
Enclosures:
- 1. List of Attendees
- 2. Licensee Handouts cc w/encls: See next page DISTRIBUTION:
PUBLIC JZwolinski/TMarsh SBloom PDI-1 Reading SRichards AHiser GVissing RLaufer TChan OGC SLittle BBateman ACRS/ACNW MKotzalas HNieh ADAMS Accession Number: ML030850136 OFFICE PDI-1/PM PDI-1/LA EMCB/SC PDI-1/SC NAME GVissing SLittle TChan RLaufer DATE OFFICIAL RECORD COPY
Calvert Cliffs Nuclear Power Plant Unit Nos. 1 and 2 cc:
President Calvert County Board of Commissioners 175 Main Street Prince Frederick, MD 20678 James Petro, Esquire Counsel Constellation Power Source 111 Market Street Baltimore, MD 21202 Jay E. Silberg, Esquire Shaw, Pittman, Potts, and Trowbridge 2300 N Street, NW Washington, DC 20037 Mark Geckle Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702 Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 287 St. Leonard, MD 20685 Mr. Richard I. McLean, Manager Nuclear Programs Power Plant Research Program Maryland Dept. of Natural Resources Tawes State Office Building, B3 Annapolis, MD 21401 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Kristen A. Burger, Esquire Maryland Peoples Counsel 6 St. Paul Centre Suite 2102 Baltimore, MD 21202-1631 Patricia T. Birnie, Esquire Co-Director Maryland Safe Energy Coalition P.O. Box 33111 Baltimore, MD 21218 Mr. Loren F. Donatell NRC Technical Training Center 5700 Brainerd Road Chattanooga, TN 37411-4017 Mr. P. E. Katz, Vice President Calvert Cliffs Nuclear Power Plant, Inc.
Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702 ATTENDEES - MEETING WITH REPRESENTATIVES OF CALVERT CLIFFS NUCLEAR POWER PLANT, INC.
REGARDING DISCUSSIONS RELATED TO THEIR RPV INSPECTION PROGRAM FOR CALVERT CLIFFS UNIT NO. 2 TUESDAY, MARCH 18, 2003 Name Affiliation Phone Number Getachew Tesfaye CCNPP (410)-495-3736 William Holston CCNPP (410)-495-4466 Tim Lupold CCNPP (410)-495-2283 Bernard C. Rudell CCNPP (410)-495-4815 Bob Hardies CCNPP (410)-495-6577 Daniel Horner McGraw Hill (202)-383-2164 John Hosmer CEG (410)-206-0787 Mike Milbradt CEG (410)-897-5074 Leslie Collins Westinghouse (301)-887-7040 Mark Geckle CEG (410)-495-2451 Jim Petro CEG (410)-468-3456 Mark Wetterhahn Winston & Strawn (202)-371-5703 Guy Vissing NRR/DLPM (301)-415-1441 Richard Laufer NRR/DLPM (301)-415-3036 Steven Bloom NRR/DLPM (301)-415-1313 Allen Hiser NRR/DE (301)-415-1034 Terence Chan NRR/DE (301)-415-2768 Bill Bateman NRR/DE (301)-415-2795