ML100110577
| ML100110577 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 01/11/2010 |
| From: | Zeller L Blue Ridge Environmental Defense League |
| To: | NRC/SECY |
| SECY RAS | |
| References | |
| 50-438-CP, 50-439-CP, Construction Permit 1, CPPR-122, CPRR-123, RAS 16960 | |
| Download: ML100110577 (24) | |
Text
1 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE SECRETARY In the Matter of Tennessee Valley Authority Bellefonte Nuclear Power Plant Units 1 and 2 Construction Permits CPPR-122 and CPPR-123 Docket Nos. 50-438 and 50-439 January 11, 2010 JOINT PETITIONERS SUPPLEMENTAL BASIS FOR PREVIOUSLY SUBMITTED CONTENTION 6 - TVA HAS NOT AND CANNOT MEET THE NRCs QUALITY ASSURANCE AND QUALITY CONTROL REQUIREMENTS In accordance with 10 CFR § 2.309(f)(2), the Blue Ridge Environmental Defense League, its chapter Bellefonte Efficiency and Sustainability Team and the Southern Alliance for Clean Energy (Petitioners) hereby submit this new and supplemental basis for Contention 6 which was submitted on May 8, 2009. Contention 6 stated: The re-instatement was improper because TVA has not and cannot meet the NRCs Quality Assurance and Quality Control requirements.
I.
BACKGROUND In the filing of May 8th, Petitioners noted that NRC had withdrawn the construction permits (CPs) for BLN Units 1 and 2 on September 14, 2006 and that Bellefonte Units 1 and 2 were therefore outside of the agencys jurisdiction for an extended period. During this time, the plant had been subject to TVAs cannibalism of
2 vital structures, systems and components. The lapse is acknowledged in a safety evaluation by the Office of Nuclear Reactor Regulation:1 Upon reinstatement of the CPs, TVA will resume preservation and maintenance activities consistent with the Commissions Policy Statement on Deferred Plants. (emphasis added)
Petitioners contend that the NRC has ignored, or minimized without justification, regulations codified in 10 CFR 50. Petition at 25.
II.
DISCUSSION Nuclear power plant construction permits are subject to federal regulations which require the prompt identification, evaluation and reporting of defects and failures of nuclear reactor structures, systems and components to the Commission by the holder of the construction permit. It is the responsibility of the director or responsible officer of a firm constructingany facilitywho obtains information reasonably indicating that the facility, activity, or basic component supplied to such facility or activity contains defects, which could create a substantial safety hazard, to immediately notify the Commission of such failure to comply or such defect. 10 CFR § 21.1. Such notification must be timely; i.e., in all cases within 60 days of discovery. 10 CFR § 50.55(e). If such identification and evaluation cannot be done within the specified time, an interim report must be submitted in writing within 60 days of discovery of the deviation.
Failure to provide such notification carries a penalty: Any director or responsible officer of an entitysubject to the regulations in this part who knowingly and consciously fails to 1 Safety Evaluation by the Office of Nuclear Reactor Regulation Relating to the Request for Reinstatement of Construction Permit Nos. CPPR-122 and CPPR-123, Bellefonte Nuclear Plant, Units 1 and 2, Docket Nos. 50-438 and 50-439 (March 9, 2009)
3 provide the notice required as by §21.21 shall be subject to a civil penalty equal to the amount provided by section 234 of the Atomic Energy Act of 1954, as amended. 10 CFR § 21.61(a)
On December 1, 2009 the Tennessee Valley Authority provided notification in writing of a Containment Vertical Tendon Coupling Failure which TVA had discovered on August 24, 2009, 108 days previously.2 According to TVA, the failure of the containment tendon occurred one week earlier, on August 17th. The actual time of the incident was deduced by TVA based on reports from as yet unidentified individuals who heard a loud noise. However, this incident is but the latest example of problems at Bellefonte Units 1 and 2. A 1985 Information Notice details failures same structures at Bellefonte:
During 1975 and 1976 a series of eight rock anchor heads, supplied by INRYCO for the containments at Bellefonte Units 1 and 2, failed during construction installation. In the phased construction process these 170-wire assemblies were sealed for long periods in a highly alkaline water environment. These anchor heads were to be coupled to the posttensioned containment vertical tendons to serve as a direct tie between the containment and the rock foundation material.
In these instances the anchor head also broke into several pieces. The licensee's investigations completed on these failures cited several possible contributors.
These included: (1) high anchor head stress as a result of a 1.4-inch-diameter hole in the head for grout passage, (2) inclusions in the steel found oriented parallel to the final failure plane, (3) bending of shims and anchor plate, and (4) unknown environmental conditions which facilitated stress corrosion cracking.
The NRC had an independent study made that concluded possible stress corrosion cracking as the initiator.
The resolution of the problem resulted in the removal of all the anchor heads and replacement with new anchor heads made from a vacuum degassed (cleaner) steel with the center grout hole eliminated and the anchor head coated for 2 Letter from Tennessee Valley Authority Vice President Jack A. Bailey to US Nuclear Regulatory Commission, December 10, 2009, ADAMS Accession No. ML093480158
4 temporary environmental protection. The NRC is aware of no further failures at Bellefonte after this corrective action. 3 The construction period, before nuclear reactor operation has begun, is a critical time for quality assurance and quality control, when some structures receive their greatest stress:
The previous history of anchor head failures before the event at Farley Unit 2, in nuclear applications, has been confined to occurrences during the construction phase (during or shortly after posttensioning). It is during this time that the tendon system, including the anchor head, undergoes the maximum loading force.4 Neither TVA nor the Commission can be certain of conditions at Bellefonte during the period after September 2006 when preservation and maintenance activities at Bellefonte had ceased. This lapse may have contributed to the August failure because rust never sleeps:5
[B]ecause the tendons are fabricated from high-strength steels [>1.6 GPa (230 ksi)] in the form of many relatively small-diameter wires or several strands fabricated from small-diameter wires, and the tendons can be subjected to stresses up to 70% of their ultimate tensile strength, they are more susceptible to corrosion than ordinary reinforcing steels and must be protected.6 The failure of the nuclear reactor containment tendon mirrors the failure of TVA to adhere to construction permit conditions which require the permit holder to implement quality assurance criteria. 10 CFR § 50.55.
3 Information Notice No. 85-10: Posttensioned Containment Tendon Anchor Head Failure, IN 85-10, February 6, 1985, Page 2 4 Id 5 Rust Never Sleeps (1979) Neil Young and Crazy Horse 6 Overview of the Use of Prestressed Concrete in U.S. Nuclear Power Plants, H. Astar, NRC Office of Regulatory Research and DJ Naus, Oak Ridge National Laboratory, page 3
5 In its recent decision regarding Bellefonte, the Commission has determined that it has the authority to reinstate the Bellefonte Construction Permits for Units 1 and 2. The decision was not unanimous. In his dissent, Chairman Jaczko said, Without continuous regulatory authority, and the associated requirements for maintenance activities and record keeping, the staff loses any assurance of the integrity or reliability of existing structures.
And further, The potential that undocumented work activities, introduction of unapproved chemicals, corrosion and other unknown degradation has occurred since the QA program was halted calls into question the integrity of and reliability of safety related structures, components and systems.
CLI-10-06 at 24.
The improper environment in the nuclear reactors containment tendon area, the loss of configuration management program and the history of prior failures all point to further problems at Bellefonte if the Commission were to allow the completion of the virtually moth-eaten 35-year old reactors following years of salvage operations and lack of maintenance and oversight.
III.
SATISFACTION OF 10 C.F.R. § 2.309(f)(2).
This supplemental filing satisfies the requirements of 10 C.F.R. § 2.309(f)(2) in the following respects:
First, the information on which the supplemental basis is based, i.e., TVAs letter to NRC was not available to Petitioners until December 10th, well after Petitioners submitted the Petition for Intervention.
Second, the information upon which the new contention is based is materially different than information that was previously available.
6 Third, this filing has been submitted in a timely fashion because neither the NRCs Power Reactor Event Report No. 45559 nor TVAs letter was available to Petitioners until 30 days ago.
IV.
CONCLUSION For the foregoing reasons, TVAs letter of December 10th and the reference documents cited herein (attached) should be made a part of the record in this proceeding and considered in the context of Petitioners Contention 6, which asserts that TVA has not and cannot meet the NRCs Quality Assurance and Quality Control requirements.
Respectfully submitted, Louis A. Zeller Blue Ridge Environmental Defense League PO Box 88 Glendale Springs, NC 28629 Phone: (336) 982-2691 Fax: (336) 977-0852 E-mail: BREDL@skybest.com
7 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE SECRETARY In the Matter of Tennessee Valley Authority Bellefonte Nuclear Power Plant Units 1 and 2 Construction Permits CPPR-122 and CPPR-123 Docket Nos. 50-438 and 50-439 January 11, 2010 CERTIFICATE OF SERVICE I hereby certify that copies of the Joint Petitioners Supplemental Basis for Previously Submitted Contention 6TVA Has Not and Cannot Meet the NRCs Quality Assurance and Quality Control Requirementswere served this day on the following persons via Electronic Information Exchange.
Office of the Secretary ATTN: Docketing and Service Mail Stop 0-16C1 US Nuclear Regulatory Commission Washington, DC 20555-0001 (E-mail: hearingdocket@nrc.gov)
Office of Commission Appellate Adjudication US Nuclear Regulatory Commission Washington, DC 20555-0001 (E-mail: ocaamail@nrc.gov)
Patrick A. Moulding, Esq.
Ann P. Hodgdon, Esq.
US Nuclear Regulatory Commission Mail Stop O-15 D21 Washington, DC 20555-0001 (E-mail: patrick.moulding@nrc.gov, ann.hodgdon@nrc.gov)
Louise Gorenflo Bellefonte Efficiency & Sustainability Team 185 Hood Drive Crossville, TN 28555 (E-mail: lgorenflo@gmail.com)
Steven P. Frantz, Esq.
Stephen J. Burdick, Esq.
Morgani, Lewis & Bockius LLP 1111 Pennsylvania Ave., NW Washington, DC 20004 (E-mail: sfrantz@morganlewis.com, sburdick@morganlewis.com)
Edward J. Vigluicci, Esq.
Scott A. Vance, Esq.
Tennessee Valley Authority 400 West Summit Hill Dr., WT 6A-K Knoxville, TN 37902 (E-mail: ejvigluicci@tva.gov, savance@tva.gov)
8 Maxwell C. Smith, Esq.
Counsel for NRC Staff US Nuclear Regulatory Commission Office of the General Counsel Mail Stop: O-15 D21 Washington, DC 20555-0001 (301) 415-1246 maxwell.smith@nrc.gov Sara Barczak, Representative of SACE Southern Alliance for Clean Energy 428 Bull Street Savannah, GA 31401 (912) 201-0354 sara@cleanenergy.org Signed this day in Glendale Springs, NC Louis A. Zeller Blue Ridge Environmental Defense League PO Box 88 Glendale Springs, NC 28629 (336) 982-2691 (336) 977-0852 (E-mail: BREDL@skybest.com)
January 11, 2010
NRC: A Prioritization of Generic Safety Issues (NUREG-0933) - ISSUE 118: TENDON AN...
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NUREG-0933 > ISSUE 118: TENDON ANCHOR HEAD FAILURE (REV. 1)
ISSUE 118: TENDON ANCHOR HEAD FAILURE (REV. 1)
DESCRIPTION Historical Background On January 27, 1985, a dented and leaking tendon grease cap was found during inspections at Farley Unit 2 prior to the integrated leak rate test of the prestressed concrete containment structure. Subsequent detailed inspection revealed that three lower vertical tendon anchor heads were broken. Several anchor heads were then removed from the vertical tendons and magnetic particle testing revealed cracks in the ligaments between the holes in the back of the anchor heads.
Metallurgical analysis of the anchor head material indicated that the failures had been caused by hydrogen stress-cracking (HSC). There was evidence of corrosion caused by hydrogen generation from the anodic reaction of zinc and steel in the presence of water since quantities of water ranging from a few ounces to about 1.5 gallons were found in the grease caps; most of the water was found in the vertical tendon lower anchor grease caps. Concerns for the generic implications of the tendon anchor failure at Farley Unit 2 resulted in the identification of this issue by DL/NRR.1352 A Task Force was assembled by the NRC to evaluate the anchor failures, including their failure mechanism and the safety significance on Farley and other plants with tendons supplied by the same vendor (INRYCO). The Task Force was to propose corrective action, determine the need for long-term generic action, prepare generic correspondence, and study the potential changes in Regulatory Guide 1.35.481 At the time the anchor head cracks were found, Regulatory Guide 1.35 was undergoing revision and the supplemental Regulatory Guide 1.35.11360 was being developed.
Work on these guides was suspended until review of the Farley tendon anchor head failure was completed.
By August 1985, the Farley anchor head failure was also studied by: (1) Inland Steel Laboratory/INRYCO, manufacturer of the Farley post-tension system; (2) Battelle Columbus Laboratories, consultant to INRYCO; and (3) BNL. In November 1985, the Task Force completed its review of the studies by these three laboratories and concluded that cracking of the anchor heads occurred in areas of high stress, was hydrogen-induced, and initiated because of the presence of water, zinc, and sulfur.
Although the Farley Unit 2 problem was concluded to be plant-specific because of the moisture-traveling path to the anchor heads, further study of the contributing factors continued.
These factors, in conjunction with the incidence of HSC of anchor heads at Bellefonte and of stress Google Custom Search About NRC Nuclear Reactors Nuclear Materials Radioactive Waste Nuclear Security Public Meetings
& Involvement Protecting People and the Environment UNITED STATES NUCLEAR REGULATORY COMMISSION
NRC: A Prioritization of Generic Safety Issues (NUREG-0933) - ISSUE 118: TENDON AN...
http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0933/sec3/118r1.html 2 of 3 1/11/2010 3:17 PM corrosion cracking of anchor bolt material at Midland, prompted the staff to investigate the potential generic implications and an action plan was developed for resolution of the issue.1358,1359 This resolution also addressed the concerns of Issue 156.2.3, "Containment Design and Inspection."
Safety Significance The failed tendon anchor heads were found to be losing the capability of carrying tendon design force. Tests on cracked anchor heads showed them to be capable of taking the original design force. However, the mechanism of crack initiation and propagation is time-dependent and eventually these anchor heads would not be able to carry the loads. Their failure could jeopardize the containment structural integrity.
Possible Solution A tendon inspection, repair, and surveillance program was initiated for both Farley Units 1 and 2.
The licensee evaluated the containments and concluded that the structural integrity had been maintained continuously for both units. Issuance of Regulatory Guides 1.35481 and 1.35.11360 would provide guidance for future p1ants.
PRIORITY DETERMINATION A regulatory analysis1353 of the proposed revision 3 to Regu1atory Guide 1.35 showed that, although the changes in the guide were determined to produce an unquantifiable change in risk, they wou1d lower the possible risk and enhance containment availability. Additional costs might be incurred by the industry (e.g., visual inspection of bottom grease caps of vertica1 tendons, and requirements for lift-off tests on the second containment where two identical containments exist at a site), but the relaxed requirements in other areas (i.e., tendon sample size and tendon detensioning) could produce a net cost savings, estimated to be small. It was concluded that backfitting of the revised guide would be very difficult for plants licensed before 1974 and would have to be done on a case-by-case basis, e.g., certain p1ants do not permit random se1ection of tendons for detensioning to remove a wire sample for material tests (See Section 6.2, NUREG/CR-4712).1353 However, the staff believed that backfitting most plants licensed after 1974 was possible. Regulatory Guide 1.35.11360 provided essentially new guidance on predicting and evaluating prestressing forces.
Ten licensee/applicants committed to various provisions of Regulatory Guide 1.35, Rev. 3 (NUREG/CR-4712, Table 4).1353 Therefore, the staff's recommendation was to apply the provisions of Rev. 3 to Regulatory Guide 1.35 to new licensing applicants only and allow other licensees to use it on a voluntary basis.1361 The proposed Regulatory Guides 1.35, Rev. 3, and 1.35.11360 were reviewed by CRGR in December 1989. CRGR concluded that there did not appear to be any substantial safety improvement in backfitting nor did the matter appear to qualify as a compliance or an adequate protection backfit.
CRGR recommended in Meeting No. 175 that the proposed guides be issued for forward-fit only.
The guides were issued in July 1990 and only affected future plants and those operating plants that voluntarily committed to the provisions of the guides.
NRC: A Prioritization of Generic Safety Issues (NUREG-0933) - ISSUE 118: TENDON AN...
http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0933/sec3/118r1.html 3 of 3 1/11/2010 3:17 PM Privacy Policy l Site Disclaimer Friday, February 23, 2007 CONCLUSION A number of licensees voluntarily adopted the provisions of Regulatory Guides 1.35,481 Rev. 3, and 1.35.11360; some SEP plants also developed ISI programs. These actions by some operating plants and the application of these guides to future plants addressed the concerns raised by the Farley Unit 2 tendon anchor head failure. The CRGR decision on the issuance of Regulatory Guides 1.35, Rev. 3, and 1.35.1 indicated that there was no need to backfit operating plants. Thus, this issue was RESOLVED and new requirements were issued. In an RES evaluation,1564 it was concluded that consideration of a 20-year license renewal period did not affect the resolution.
SSINS No.: 6835 IN 85-10 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 February 6, 1985 Information Notice No. 85-10: POSTTENSIONED CONTAINMENT TENDON ANCHOR HEAD FAILURE Addressees:
All nuclear power reactor facilities holding an operating license (OL) or a construction permit (CP).
Purpose:
This information notice is provided to alert recipients of current information relating to a potentially significant problem regarding recent failures of 170-wire posttensioned containment tendon anchor heads at Unit 2 of the Farley Nuclear Station. It is expected that recipients will review the information for applicability to their facilities and consider actions, if appropriate, to detect a similar problem at their facilities. However, suggestions contained in this information notice do not constitute NRC requirements; therefore, no specific action or written response is required.
NRC is continuing to obtain and evaluate pertinent information. If specific actions are determined to be required, an additional notification will be made.
Description of Circumstances:
Farley Unit 2 On January 28, 1985, while conducting a preintegrated leak rate test walkdown of the exterior of the containment structure at the Farley Unit 2 facility, an alert utility worker noted grease leakage and a deformed vertical tendon anchor grease cap on the top of the containment ring beam.
When the grease cap on the same tendon was inspected in the tendon access gallery, it also revealed a deformed grease cap. Removal of the grease cap showed that the field anchor head had broken into seven pieces. The posttensioning force (approximately 1.5 x 10-6 pounds) also had been released and numerous broken wires from the 170-wire tendon were found.
On the basis of this finding, the utility removed some additional tendon anchor grease caps. Of the first eight anchor heads uncovered for inspection, one was found to be cracked. Inspection was curtailed until the cracked anchor head can be detensioned. The tendon associated with this anchor head is still transmitting posttensioning force to the containment.
The utility determined from their records that the broken anchor head and the cracked anchor head have the same fabrication lot control number.
8502060136 IN 85-10 February 6, 1985 Page 2 of 3 Google Cus Index l Site Map l FAQ l Facility Info l Reading Rm l New l Help l Glossary l Contact Us Home > Electronic Reading Room > Document Collections > General Communications > Information Notices > 1985 > IN 8 About NRC Nuclear Reactors Nuclear Materials Radioactive Waste Nuclear Security Pub Protecting People and the Environm UNITED STATES NUCLEAR REGULATORY COMMISSION Page 1 of 3 Information Notice No. 85-10: Posttensioned Containment Tendon Anchor Head Failure 1/11/2010 http://www.nrc.gov/reading-rm/doc-collections/gen-comm/info-notices/1985/in85010.html
Additionally, the utility has sent some of the pieces of the broken anchor head to two laboratories for a series of tests for failure analysis, including tests on metallurgical, mechanical, chemical and other physical properties. Testing of the corrosion inhibitor grease is under way.
Currently, the utility has personnel from the architect-engineer and the material supplier on-site in the continuing investigation. Neither the NRC nor the licensee has yet fully integrated the information regarding the results of previous tendon surveillance activities at the Farley site into this information notice. Oral information from the licensee indicates the tendons at Farley Unit 2 were posttensioned in early 1977. The unit has been operational since May 1981. The specific tendon whose anchor head failed and the one found with a cracked anchor head were not included in the sample of tendons that were subjected to surveillance activities since the plant began operation. Thus, there is no definitive information currently available on the time of occurrence of the breakup of the one anchor head or the crack formation in the other anchor head.
While no specific conclusions have been reached at this time regarding the cause of the failures, the NRC believes that based on the conversations with the supplier, INRYCO, that all material from the same fabrication lot control number as the failed heads was utilized exclusively at Farley Unit
- 2.
The previous history of anchor head failures before the event at Farley Unit 2, in nuclear applications, has been confined to occurrences during the construction phase (during or shortly after posttensioning). It is during this time that the tendon system, including the anchor head, undergoes the maximum loading force.
As background information,, previous 170-wire tendon anchor head failures during construction at other facilities are briefly summarized below.
Bellefonte Units 1 and 2 During 1975 and 1976 a series of eight rock anchor heads, supplied by INRYCO for the containments at Bellefonte Units 1 and 2, failed during construction installation. In the phased construction process these 170-wire assemblies were sealed for long periods in a highly alkaline water environment. These anchor heads were to be coupled to the posttensioned containment vertical tendons to serve as a direct tie between the containment and the rock foundation material. In these instances the anchor head also broke into several pieces. The licensee's investigations completed on these failures cited several possible contributors. These included: (1) high anchor head stress as a result of a 1.4-inch-diameter hole in the head for grout passage, (2) inclusions in the steel found oriented parallel to the final failure plane, (3) bending of shims and anchor plate, and (4) unknown environmental conditions which facilitated stress corrosion cracking. The NRC had an independent study made that concluded possible stress corrosion cracking as the initiator.
The resolution of the problem resulted in the removal of all the anchor heads and replacement with new anchor heads made from a vacuum degassed (cleaner)
IN 85-10 February 6, 1985 Page 3 of 3 steel with the center grout hole eliminated and the anchor head coated for temporary environmental protection. The NRC is aware of no further failures at Bellefonte after this corrective action.
Byron Units 1 and 2 In November of 1979 two 170-wire anchor heads on horizontal tendons were reported to have failed during construction of the Byron containments. One failure occurred one day after stressing and seating the tendon and the other occurred 13 days after stressing and seating. By the end of January 1980, two additional anchor heads had been reported as having failed. The supplier of the anchor heads was INRYCO. Investigations were made by INRYCO on the material from seven separate fabrication lots. It was found that the basic steel material used in several of the batches had been manufactured by Page 2 of 3 Information Notice No. 85-10: Posttensioned Containment Tendon Anchor Head Failure 1/11/2010 http://www.nrc.gov/reading-rm/doc-collections/gen-comm/info-notices/1985/in85010.html
a process that utilized vanadium grain refinement causing an incompatibility with the postfabrication heat treatment. This resulted in a different steel chemistry that would have required a higher temperature for proper heat treatment. As a result of this conclusion all anchor heads that had received improper heat treatment for the basic steel chemistry were removed and replaced. The NRC is not aware of any failures at Byron since the corrective action.
Discussion Because the integrity of the posttensioned concrete containment structure is based on a highly redundant system of numerous tendon elements (several hundred), the failure of one such element in a family of tendons does not jeopardize containment structural capability. It does, however, necessitate a determination that a mechanism or systematic problem has not arisen under service conditions when one such failure in a tendon is revealed. Specific tendon geometry, tendon size, containment design details, and location of individual tendons with lost or lowered strength properties would dictate the critical number of tendons that could be lost before containment integrity is jeopardized.
No specific action or written response is required by this information notice. If you have any questions about this matter, please contact the Regional Administrator of the appropriate regional office or this office.
Edward L. Jordan Director Division of Emergency Preparedness and Engineering Response Office of Inspection and Enforcement Technical
Contact:
R. Shewmaker, IE (301) 492-7432
Attachment:
List of Recently Issued IE Infomation Notices Page 3 of 3 Information Notice No. 85-10: Posttensioned Containment Tendon Anchor Head Failure 1/11/2010 http://www.nrc.gov/reading-rm/doc-collections/gen-comm/info-notices/1985/in85010.html