ML20140E933
| ML20140E933 | |
| Person / Time | |
|---|---|
| Site: | Portsmouth Gaseous Diffusion Plant |
| Issue date: | 06/09/1997 |
| From: | John Miller UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | Paperiello C NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| GDP-97-0092, GDP-97-92, NUDOCS 9706120255 | |
| Download: ML20140E933 (14) | |
Text
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United Statzs Enrichm ntCorporation 2 Democracy Center 6903 Rockledge Drive Bethesda, MD 20817 b
Tel: (301)S64-3200 Fax:(301) 564-3201 Uniteti Slates lUlrichinent CorlH> ration i
JAMES H. MILLER Dir: (301) 564-3309 VICE PRESIDER, PRODUCTION Fax: (301) 571-8279 1
June 9,1997 Dr. Carl J. Papeliello SERIAL: GDP 97-0092 Director, Office of Nuclear Material Safety and Safeguards Attention: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Portsmouth Gaseous Diffusion Plant (PORTS)
Docket No. 70-7002 Certificate Amendment Request-Autoclave Containment Valve Pressure Decay Testing
Dear Dr. Paperiello:
In accordance with 10 CFR 76.45, the United States Enrichment Corporation (USEC or Corporation) hereby submits a request for amendment to the certificate of compliance for the Portsmouth, Ohio Gaseous Diffusion Plant (GDP). This certificate amendment request revises Technical Safety Requirement (TSR) Section 2.1.3.5, Autoclave Shell High Pressure Containment Shutdown, to reflect that both the inner and onter loop containment valves have the ability to be independently tested during the autoclave pressure decay test.
Issue 3 of the Plan For Achieving Compliance with NRC Regulations for the Portsmouth Gaseous Diffusion Plant, requires in part that the capability be provided to separately test both the inner and outer loop containment valves on the autoclaves in X-342A, X-343 and X-344A. The revision to TSR 2.1.3.5 provided in this Certificate Amendment Request reflects the capability to perform this testing.
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fGC FILE CEMEB COPY
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9706120255 970609 PDR ADOCK 07007002 g
C PDR Offices in Paducah, Kentucky Portsmouth. Ohio Washington. DC
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D'r. Carl J. Paperiello June 9,1997
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l GDP 97-0092 Page 2
- to this letter provides a detailed description and justification for the proposed changes I
to TSR 2.1.3.5. Enclosure 2 is a copy of the revised TSR pages for your review and approval. Enclosure t
3 contains the basis for USEC's determination that the proposed change associated with this certificate l
1 amendment request is not significant.
l Since this certificate amendment request is not required to support continued plant operation, USEC i
i requests NRC review and approval of this certificate amendment request at your earliest convenience.
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The amendment should become effective 60 days from issuance.
l Any questions related to this subject should be directed to Mark Smith at (301) 564-3244.
Sincerely, i
/20-es H. Miller i
Vice President, Production
Enclosures:
As Stated cc:
NRC Region Ill Office NRC Resident Inspector - PGDP NRC Resident Inspector - PORTS DOE Regulatory Oversight Manager
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OATH AND AFFIRMATION l
I, James H. Miller, swear and affimi that I am Vice President, Production, ofthe United States i
Enrichment Corporation (USEC), that I am authorized by USEC to sign and file with the Nuclear 3
l 1-Regulatory Commission this Certificate Amendment Request for the Portsmouth Gaseous Diffusion 1
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. Plant, that I am familiar with the contents thereof, and that the statements made and matters set forth therein are true and correct to the best of my knowledge, information, and belief.
bames H. Miller i
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Subscribed to before me on this day of b,
,1997.
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Notary Public t w x E c.tich r:I pot /r/ T4*E STATE CMMiAC Cor6ce Ik<1in Mct130" /C:cet/
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GDP97-0092 Page 1 of 2 United States Enrichment Corporation (USEC)
Proposed Certificate Amendment Request Autoclave Containment Valve Pressure Decay Testing Detailed Description of Change 1
Specific TSR Sections Affected The proposed change would revise TSR Section 2.1.3.5, Autoclave Shell IIigh Pressure Containment Shutdown, to reflect that both the inner and outer loop containment valves will be independently tested during the autoclave pressure decay test. In addition, the Required Action table for TSR 2.1.3.5 will be revised to indicate that upon inoperability of a single containment valve on one or more autoclave penetrations, the operating cycle in progress may continue.
TSR 2.1.3.5, Required Action A.1 was revised to clarify the previous statements and to utilize the term " Operating Cycle", which is defined m TSR 1.2.14, instead of referring to the applicable operating modes.
A new Condition C was added to the Required Actions for the purpose of re-establishing the condition to address the times when there is only one comainment valve within an autoclave penetration inoperable. Issue 3 of the Compliance Plan required that until such time as the inner and outer containment valves were tested separately, the TSR was to indicate that the inoperability of a single containment valve also required the autoclave to be declared inoperable. The existing Condition C was relabeled as Condition D and revised to apply to the inoperability of both containment valves in any one autoclave penetration. The existing Condition D was relabeled Condition E.
TSR 2.1.3.5 surveillance requirement SR 2.1.3.5.3 was revised to incorporate the requirement to test separately the inner and outer containment valve loops as part of the autoclave decay test.
Reason for Change Issue 3 of the Plan For Achieving Compliance with NRC Regulations for the Portsmouth Gaseous Diffusion Plant, requires in part, that modifications be performed to allow separate pressure decay testing for both the inner and outer loop containment valves.
i GDP97-0092 Page 2 of 2 P
United States Enrichment Corporation (USEC)
Proposed Certificate Amendment Request Autoclave Containment Valve Pressure Decay Testing Detailed Description of Change 1
1 Justification of the Change The autoclaves in buildings X-342, X-343 and X-344 were designed and constructed in accordance with ASME Section VIII and are utilized to contain the contents of a UF cylinder in the event of a 6
major UF release within the autoclave. Each line which penetrates the autoclave boundary has 6
isolation valve (s) which close to isolate the autoclave in the event of high autoclave pressure, preventing an external release of UF, except that which may be released due to the proper operation i
6 of the autoclave pressure relief system. The containment function is in part, demonstrated by the j
periodic pressure decay test of the autoclaves as delineated in TSR 2.1.3.5.
As noted in Issue 3 of the Compliance Plan, the capability to test the containment valves (i.e., inner and outer loop valves) separately for the autoclaves in X-342, X-343 and X-344 was not provided.
This certificate amendment request revises TSR 2.1.3.5 to require that the inner and outer loop containment valves be tested separately at the peak credible accident pressure that could be attained, based upon the existing accident analysis. The capability to separately test the inner and outer loop containment valves will enhance the TSR pressure decay test surveillance by prov: Jing additional assurances that the autoclave containment function will perform as assumed in the accident analyses.
GDP97-0092 Page 1 of 4 Proposed Certificate Amendment Request Portsmouth Gaseous Diffusion Plant Letter GDP97-0092 Removal / Insertion Instructions Remove Page Insert Page VOLUME 4 TSR 2.1.3.5 TSR 2.1.3.5 Page 2.1-11 and 2.1-12 Page 2.1-11 and 2.1-12
TSR-PORTS PROPOSED June 9,1997 RAC 97X0288 (RO)
SECTION 2.I SPECIFIC TSRs FOR X-342, X-343, AND X-344 FACILITIES 2.1.3 LIMITING CONTROL SETTINGS, LIMITING CONDITIONS FOR OPERATION, SURVEILLANCES 2.1.3.5 Autoclave Shell Ifigh Pressure Containment Sliutdown APPLICABILITY:
Autoclave Operational Modes II, IV, VI LCO:
The autoclave shell high pressure containment system shall be operable:
ACTIONS:
i Condition Required Actions Completion Time A.
One instrument A.1 Restore instrument channel to operable status.
Prior to initiating channel inoperable a new Operating NOTE Cycle The current Operating Cycle may be completed.
B.
Both instrument B.1 Place autoclave in Mode VII 1 Hour channels inoperable C.
One containment C.1 Restore containment isolation valve to operable Prior to initiating isolation valve on status.
a new Operating one or more NOTE Cycle autoclave The current Operating Cycle may be completed, penetration inoperable D.
All containment D.1 Place ai.toclave in Mode VII 1llour l
isolation valves on any one autoclave penetiation inoperable E.
Steam leakage E.1 Place autoclave in Mode Vil 1 flour l
around autoclave locking rmg j
2.1-11
4.
TSR-PORTS PROPOSED June 9,1997 RAC 97X0288 (RO)
SECTION 2.1 SPECIFIC TSRs FOR X-342, X-343, AND X-344 FACILITIES 2.1.3 LIMITING CONTROL SETTINGS, LIMITING CONDITIONS FOR OPERATION, SURVEILLANCES 2.1.3.5 Autoclave Shell Iligh Pressure Containment Shutdown (continued)
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SURVEILLANCE REQUIREMENTS:
Frequency Surveillance Quarterly SR 2.1.3.5.1 Perform channel functional test to verify the liigh Pressure Containment system will actuate at or below 15 psig Semiannually SR 2.1.3.5.2 Calibrate shell high pressure shutdown instrumentation at s 15 psig Quarterly SR 2.1.3.5.3 Leak rate the autoclave by pressurizing the autoclave to at least 90 psig and verify that the system pressure loss is less than or equal to 10 psig/hr for each of the following autoclave loop containment valve conditions:
1.
Inner loop valves closed and Outer loop valves open 2.
Inner loop valves open and Outer loop valves closed OR Perform a leak rate test where the maximum acceptable leakage shall not exceed 12 scfm at a minimum test pressure of 90 psig for each of the same conditions as stated above.
l Note: Allowable test tolerance to cover instrument drift and uncertainties during normal operation
= +2 psig BASIS:
The steam used to heat a cylinder within an autoclave is controlled at approximately 5 psig. Therefore, when the autoclave internal pressure reaches 15 psig, the operating logic assumes that a UF. release has occurred within the autoclave and causes the containment valves to close, preventing an external release of UF.. The 15 psig represents the lowest pressure at which it can be assumed that it is not due to a steam control failure and yet gives the early indication that a UF. release is in progress. Testing the containment system at 90 psig is representative of the peak credible accident pressure that could be attained assuming functioning of safety systems, design features and administrative controls to prevent rupture of a cylinder or pigtail. The set point value correrponds to the trip set point established under DOE 5481.1B in 1985 and amended by DOE approval in 1995 to allow a 2 psi tolerance to comply with the defimtion of
" Allowable Value" in ANSI /ISA-S67.04-1988 [SAR Seciion 3.2.1.1.1].
2.1-12
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GDP97-0092 Page 1 of 3 United States Enrichment Corporation (USEC)
Proposed Certificate Amendment Request j
Autoclave Containment Valve Pressure Decay Testing Significance Determination The United States Enrichment Corporation (USEC) has reviewed the proposed changes associated with this certificate amendment request and provides the following Significance Determination for consideration.
1.
No Significant Decrease in the Effectiveness of the Plant's Safety. Safeguards or Security Programs The testing of the autoclave containment function by performing a pressure decay test of the autoclave and the inner / outer loop containment valves is not addressed in plant safety, safeguards or security programs contained in Volume 3 of the Application for United States Nuclear Regulatory Commission Certification for the Portsmouth Gaseous Diffusion Plant.
Therefore, the effectiveness of these programs is unaffected by these changes.
2.
No Significant Change to Any Conditions to the Certificate of Comnliance None of the Conditions to the Certificate of Compliance for Operation of Gaseous Diffusion Plants (GDP-2) specifically address TSR required actions or related surveillances. Thus, the proposed change has no impact on any of the Conditions to the Certificate of Compliance.
3.
No Significant Change to Any Condition of the Annroved Comnliance Plan Issue 3 of the Plan For Achieving Compliance with NRC Regulations for the Portsmouth Gaseous Diffusion Plant, requires in part, that modifications be performed to allow separate pressure decay testing for both the inner and outer loop containment valves. The proposed changes are submitted in accordance with the Compliance Plan and create no additional changes to the Compliance Plan nor to any conditions of the Compliance Plan.
4.
No Significant Increase in the Probability of Occurrence or Consecuences of Previousiv Evaluated Accidents Installing the capability to separately test the inner and outer loop containment valves will enhance the TSR pressure decay test surveillance by providing additional assurances that the autoclave containment function will perform as designed. The operation of ~the autoclave containment valves is not defined as an accident initiator in the SAR analysis and therefore,
GDP97-0092 Page 2 of 3 Uni;cd States Enrichment Corporatioin (USEC)
Proposed Certificate Amendment Request Autoclave Containment Valve Pressure Decay Testing Significance Determination 4
the testing of the valves will not affect the probability of occurrence of any postulated accident in the SA R.
Since the proposed testing changes provide enhanced assurance that the containment function will be available, if required, the consequences of previously evaluated accidents for which credit was taken for the containment function, will remain unchanged.
I 5.
No New or Different Tyne of Accident 1
The revision of TSR 2.1.3.5 to provide for the separate testing of the inner and outer loop 4
containment valves will not create a new or different type of accident than those previously analyzed. The change will not add any new accident initiator or plant configuration that could j
lead to a new or different type of accident.
6.
No Sienificant Reduction in Marcins of Safety i
Testing of the inner and outer loop containment valves demonstrates the ability to establish containment in the event of a UF. release within the autoclave. The proposed changes enhance the availability of the autoclave containment function and therefore, the proposed changes will increase the margin of safety over that previously experienced under the existing pressure decay testing criteria.
7.
No Significant Decrease in the Effectiveness of any Programs or Plans Contained in the Certificate Annlication The TSR changes that require the independent testing of the inner and outer loop containment valves are not specifically addressed in any programs or plans contained in the Certificate Application. Therefore, the revision of TSR 2.1.3.5 to enhance the testing of the autocleve containment function will not decrease the effectiveness of these programs or plans.
8.
The Pronosed Changes do not Result in Undue Risk to 1) Public Health and Safety. 2)
Common Defense and Security. and 3) the Environment.
The proposed changes to TSR 2.1.3.5 permit the independent testing of the umer and outer loop containment valves. Independent testing of these valves demonstrates the ability to establish containment in the event of UF leakage from the cylinder into the autoclave. As such, these changes represent a reduction in risk to the public health and safety. In addition, these revisions have no impact on plant effluents or on the programs and plans in place to
GDP97-0092 Page 3 of 3 j
Unitc<l States Enrichment Corporation (USEC)
Proposed Certificate Amendment Request Autoclave Containment Valve Pressure Decay Testing Significance Determination
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implement physical security. Consequently, these proposed changes only enhance safety and pose no undue risk to the environment or the common defense and security.
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9.
There is No Change in the Tynes or Significant Increase in the Amounts of Anv Effluents that l
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may be Released Offsite.
This change has no effect on the generation of effluents and therefore, it does not change the type ofeffluents that may be released offsite. Since the independent testing of the inner and outer loop containment valves will provide added assurance that in the event of an internal autoclave UF release the UF. will be contained, there should not be any increase in the amount of effluents released offsite.
10.
There is No Significant Increase in Individual or Cumulative Occunational Radiation Exoosure.
The consequences of a UF release associated with any postulated accident currently identified in the SAR will not increase as a result of enhancing the autoclave containment valve testing.
This change does not increase the probability of a UF. release in an autoclave. The independent testing of the inner and outer loop containment valves will not affect the radiological protection program actions in place to minimize occupational exposures.
Therefore, there is no increase in individual or cumulative occupational radiation exposure as a result of this proposed change.
I1.
There is No Significant Construction Imnact.
In order to perform the independent testing of the autoclave inner and outer loop containment valves, a plant modification is required. Since this change can only occur after the modification is complete, it will not impact construction, and, therefore, there is no significant construction impact.
12.
There is No Significant Increase in the Potential for R.adiological or Chemical Consecuences from Previousiv Analyzed Accidents.
The revision of TSR 2.1.3.5 will not increase the probability of occurrence or consequences (radiological and/or chemical) of any postulated accident currently identified in the SAR. The enhancing of the autoclave containment valve testing does not alter the assumptions used in the accident analysis. Therefore, there is no significant increase in the potential for radiological or chemical consequences from previously analyzed accidents.
Fr(OM sUSEC 301-564-3210 1997.06-10 13: 45
- 565 P 01/03 UNITED STATES ENRICHMENT CORPORATION Two Democracy Center
- 4th Floor a 6903 Rockledge Drive e Bethesda, MD 20817 i
Fax Memorandum DATE:
June 10.1997 TIME:
12:37 om TO:
Yawar Faraz FAX:
PHONE:
FROM:
Mark Lombard FAX:
301 564-3210 PHONE:
301 584-3248 NUMBER OF PAGES (including cover shoot): 3
SUBJECT:
Attached is an agenda for this afternoon's conference call at 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br /> to discuss the HEU cylinder valve changeout issue, and a copy of the planned revision to SAR Section 3.7.1. Please call if you have any questions, otherwise we will talk this afternoon. Thank you.
() C f( C h b ' ] b b Q
FQOM IUSEC 301-564-3210 1997.06-10 13:45
- 565 P.02/03 Aaenda for 6/10/97 Conference Cail Explanation of the issue-why change out of the HEU cylinder valves is i
necessary Why X-705 is the safest place to do the change out What are the Application changes that are necessary SAR Section 3.7.1 Changes can be done under 76.68 SAR Section 3.3.1.3.1.3 already discusses this activity i
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FROM IUSEC 301-564-3210 1997.06-10 13:45
- 5E5 P.02/03 SAR-PORTS May 31,1996 Rev.3 After a cylinder has been fed, it is removed from the feed position and weighed to determine the amount of uranium fed to the LEU enrichment process. A relatively smali amount of non-volatile uranium typically remains in the cylinders after feeding. This " heel" is removed by a cleaning process conducted in a DOE-regulated X-705 Small Cylinder Cleaning area or slupped offsite for cleaning. Solutions resulting from the cleaning process are blended with solutions comWng normal, depleted or LEU to reduce the assay to less than 10 wt-% "U. The solution is then transferred to the uranium recovery area where it is converted to urannun oxides; finally the oxides are stored for future disposition. The cleaned cylinders and any cylinders destroyed during the cleaning process are returned to DOE.
As a part of the normal operation of the gaseous diffusion process, cells are treated whh oxidant gases to remove deposits of uranylIluoride and other compounds from the cascade equipment surfaces in a manner descr bed in Section 3.1.1.12. Generally, these treatments hterate a few hundred to several thousand grams i
of uranium from deposits. The treatment gases, including any uranmm liberated from deposits as UN are evacuated to surge drums and then returned to the enndunent cascade at a point near its origin.
Cell treatment may result in the liberation of small quantities of residual HEU that was left in USEC process equipment following completion of the DOE cleanup process. This may occur at any point during the remaining operational life of the enrichment cascade. The liberated HEU material will mix with the LEU material in the process equipment and surge drums and the treatment gases T.ill be returned to the cascade, where it will be mixed with the much larger quantities of uranium present in the interstage flow at LEU enrichments. This process ensurcs that the blended stream remains whhin the "U possession limits defined in Table 1-3. Analysis of uramum enrichment is not performed prior to returmng the mixtures to the cascade.
Any changes in uramum inventory due to " recovery" of the relatively small amounts of HEU would be reflected in USEC's enrichment cascade'Invemory Difference (ID) during periodic inventories.
In addition to the HEU downblending activities, there may be occasions when equipment or components removed from the LEU cascade, X-705 Building or other leased areas contain moderately (10-20 wt-% *U) enriched or highly ennched urantum due to the presence of residual deposits of material that were not completely removed during the HEU Suspension program. On those limited occasions when this occurs, the equipment will be disassembled and decontaminated in an area in the X-705 Bitilding which is placed temporarily under DOE regulation with appropriate afeguards in place. This procedure will also apply in those limited occasions when HEU cylinder valves require changeout due to bent stems or other valve problems which prevent the valves from being manipulated. The valve changeout will be handled in an area of the X-705 building which is temporarily mrned over to DOE regulation with appropriate safeguards in placc. Any material removed during these operations which exceeds 10 wt-% *U will be retained by DOE or will be blended with LEU solution urnil the overall enrichment is less than 10 m-% *U. DOE regulation and associated safeguards will cease to la applied when material equal to or greater than 10 wt-% *U is no
'onger present. The blended <bwn solution would be processed through uranium recovery as described above.
3.7.2 Organization and Responsibilities DOE will retain regulatory authority over HEU, except for inaccessible residaal holdap and Category S
III quanuties (or less) of other HEU. Up to 50 kg of U, contained in uranium enriched from 10 wt-% up to 20 wt-% "U, may be present in Units X-25-7 and X-27-2, interconnecting piping and the X-326 surge drums in the gas phase during routine operations, as a result of HEU refeed. This equipment, its inventory 3.?-2