|
---|
Category:INTERNAL OR EXTERNAL MEMORANDUM
MONTHYEARML20217M6061999-10-20020 October 1999 Notification of 991102 Meeting with Util in Port Gibson,Ms to Discuss Bases for Emergency Preparedness Plan Change Submitted in & Supplemented by 990120 & 0715 Ltrs IR 05000416/19990021999-09-10010 September 1999 Notification of Significant Licensee Meeting with Entergy Operations,Inc on 991018 to Discuss Listed Topics Identified in NRC Insp Repts 50-416/99-02,99-03 & 99-06 ML20211K7171999-09-0202 September 1999 Forwards Ineel Technical Ltr Rept, Evaluation of Fuel Pin Failure Timing in Boiling Water Reactors Dated 990730.Rept Used for Review of BWROG Rept on Revised Source Term Accident Analysis ML20211H4441999-08-27027 August 1999 Notification of Significant Meeting with Util on 990916 & 17 in Arlington,Tx to Improve Utility & NRC Understanding of Industry & Regulatory Perspectives on Current Issues ML20209G2421999-07-14014 July 1999 Notification of 990722 Meeting with License in Rockville, MD to Discuss Changes in EOI Licensing Organization Including Division of Responsibilities within New EOI Corporate Licensing Group ML20196F0391999-06-23023 June 1999 Notification of 990707 & 08 Meeting with EOI in Conference 1 at GGNS Energy Svc Ctr to Discuss Low Power Shutdown Risk Assessment Methods & Associated Probabilistic Risk Assessment Model ML20207A2551999-05-18018 May 1999 Notification of 990603 Meeting with EOI in Rockville,Md to Discuss EOI Submittal on BWROG Source Term Analysis & Possible Related Future Amend Requests from EOI ML20205R8871999-04-20020 April 1999 Notification of 990504 Meeting with Util in Rockville,Md to Discuss Proposal to Submit Consolidated Security Plan for Util Sites ML20205B8871999-03-26026 March 1999 Notification of 990415 Meeting with Utils in Knoxville,Tn to Visit Test Site & Discuss Test Program for ECCS Suppression Pool Suction Strainer.Context of Meeting Considered Entirely Proprietary ML20204B3041999-03-15015 March 1999 Notification of Licensee Meeting with Util in Energy Svc Ctr,Grand Gulf Site on 990415 to Discuss Plant Performance Review Results.Meeting Open to Public ML20195G1121998-11-17017 November 1998 Notification of 981201-02 Meeting with Entergy Operations in Taft,Louisianna to Conduct Joint Workshop for Licensing Personnel from Entergy & Nrc,Project Directorate IV-1 ML20151X1651998-09-14014 September 1998 Notification of Significant Licensee Meeting W/Util on 980929 to Discuss Emergency Preparedness Activities & Issues ML20151U7971998-09-0808 September 1998 Notifies of 980929 Meeting with Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring Quality Assurance Plan Details from Current Program Plans at Four Sites to Std Quality Assurance Program Plan ML20153H6671998-09-0808 September 1998 Revised Notification of 981007 Meeting with Util to Discuss Level of Instructions & Details for Transferring QA Plan Details from Current Program Plans at Four Sites to Std Program Plan at All Sites.Originally Scheduled for 980929 ML20238F5861998-08-28028 August 1998 Notification of 980909 Meeting w/BWR/6S:EOI & Listed Utils in Rockville,Md to Discuss W/Nrc Planned Applications by Licensees to Reduce Operability Requirements During Refueling Outages ML20237A2811998-08-12012 August 1998 Notification of 980827 Meeting W/Nrc & Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring QA Plan Details from Current Program Plans at Four Sites ML20249A2101998-06-11011 June 1998 Notification of 980702 Meeting W/Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring Quality Assurance Plan Details from Current Program Plans at Four Sites to Std Quality Assurance Program Plan for Site ML20248M0751998-06-0909 June 1998 Notification of 980625 Meeting W/Util in Rockville,Md to Discuss Installation & Design of Suppression Pool ECCS Strainer to Meet NRC Bulletin 96-003 IR 05000416/19983011998-05-26026 May 1998 Forwards NRC Operator Licensing Exam Rept 50-416/98-301 for Tests Administered on 980330-0403 ML20248B4181998-05-26026 May 1998 Forwards NRC Operator Licensing Exam Rept (Including Completed & Graded Tests) for Tests Administered on 980330- 0403 ML20216D6351998-04-13013 April 1998 Notification of 980416 Meeting W/Util in Rockville,Md to Discuss Entergy Operations,Inc Initial Proposal to Standardize Security Plans for Listed Plants ML20217E8471998-03-26026 March 1998 Notification of Significant Licensee Meeting W/Util on 980402 to Discuss Entergy Operations,Inc Annual Performance Assessment ML20216H9441998-03-19019 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md for Licensee to Brief Staff on Risk Mgt for Upcoming 9th Refueling Outage Scheduled to Begin on 980411.Licensee Will Do Presentation to Meet NRC Bulletin 96-003 ML20216J4051998-03-18018 March 1998 Forwards SER Authorizing Licensee 980211 & 0310 Ltrs, Requesting Approval of Alternative Reactor Weld Exam,Per Provisions of 10CFR50.55a(a)(3)(i) & 10CFR50.55a(g)(6)(ii) for Plant for Next 2 Operating Cycles ML20216C8601998-03-11011 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md to Discuss Design of Suppression Pool Strainer to Meet Bulletin 96-03 ML20217F2521998-03-11011 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md to Discuss Design of Suppression Pool Strainer to Meet NRC Bulletin 96-003.Meeting Cancelled as of 980326 ML20197B8721998-03-0505 March 1998 Notification of 980401 Meeting W/Util in Jackson,Ms to Discuss Licensing Issues & Regulatory Performance Efficiencies W/Licensing Staff for Plants.Meeting Agenda Encl ML20203B4131998-02-0505 February 1998 Notification of 980319 Meeting W/Entergy Operations,Inc,In Rockville,Md to Discuss Level of Instructions & Details of Transferring QA Plan Details from Current Program Plans at Four Sites to Standard QA Program Plan for Use at All Sites ML20198M8351998-01-12012 January 1998 Notification of 980122 Meeting W/Util in Rockville,Md to Discuss Site Licensing Status for Listed Plants & to Explore Ways to Standardize Licensing Submittals & Issuances ML20198M7531998-01-12012 January 1998 Notification of Meeting W/Entergy Operations,Inc,On 980123 in Rockville,Md to Discuss Plans to Change Radiological Emergency Response Plan ML20198K0791997-10-15015 October 1997 Notification of 971022 Meeting W/Entergy Operations,Inc in Rockville,Md Re Standard Quality Assurance Manual for Entergy Sites ML20217D0461997-09-29029 September 1997 Notification of Significant Licensee Meeting W/Util on 971029 to Discuss Systematic Assessment of Licensee Performance ML20141E8501997-06-27027 June 1997 Notifies of 970710 Meeting W/Licensee in Rockville,Md Re Appeal of Decision by Nrc,In ,That Changes in Rev 28.001-95 of Plant Emergency Plan Not within 10CFR50.54(q) & Can Not Be Implemented W/O Prior NRC Approval ML20137W6841997-04-15015 April 1997 Notification of 970502 Meeting W/Listed Attendees in Jackson,Mi.Meeting Agenda Encl ML20137F2351997-03-24024 March 1997 Summary of 970207 Meeting W/Listed Attendees in Rockville,Md to Discuss Nuclear Energy Inst Concerns Re Graded Quality Assurance Activities W/Volunteer Plants ML20137C9201997-03-20020 March 1997 Forwards Documentation of Meeting Conducted in Region 4 Office on 970225 to Discuss NRC Enforcement Policy as Applied to Nonescalated Enforcement ML20135F8581997-03-13013 March 1997 Notification of 970424 Licensee Meeting W/Util in Arlington, Tx to Discuss Current Performance ML20135F0921997-03-0606 March 1997 Notification of Significant Licensee Meeting W/Util on 970319 to Discuss Current Performance.Meeting Cancelled ML20135D8531997-03-0303 March 1997 Notification of 970325 Meeting W/Util in Port Gibson,Ms to Discuss MOV Thurst Methodology Developed by Util.Subj Methodology Being Applied in Licensee Response to GL 95-07 ML20135D7791997-02-27027 February 1997 Notification of Significant Licensee Meeting W/Entergy Operations,Inc on 970319 in Arlington,Tx to Discuss Current Performance ML20134M2471997-02-14014 February 1997 Submits List of Plants Not Meeting Selection Criteria for Ti 2515/118 Insp on Basis of Factors Such as SWS Operating Experience,Contribution of SWS to Plant Risk Assessment, Licensee Programs in Response to GL-89-13 ML20135B6231996-11-27027 November 1996 Notification of 961217 Licensee Meeting W/Util in Arlington, Tx to Discuss Evaluation Approach & Results of UFSAR Assessments at Each Facility ML20134L6121996-11-19019 November 1996 Notification of 961121 Meeting W/Entergy Operations,Inc,In Rockville,Md to Discuss Views on Funding for Decommissioning Costs of Nuclear Power Plants as May Apply for Each of Four Nuclear Plant Sites ML20129K1821996-11-0606 November 1996 Notification of 961121 Visit to Plant to Review Component Procurement Packages Using Graded Quality Assurance That Have Been Completed by Licensee ML20134C9121996-10-0808 October 1996 Notification of 961114 Meeting W/Util in Rockville,Md to Discuss Results of Self Assessment of Accuracy of Info in FSAR for Each Plant Site ML20134B5061994-04-13013 April 1994 Submits Plants Which Will Be Discussed in Categories Indicated Re Results of Screening Meetings for June 1994. Partially Deleted ML20149D7871993-12-20020 December 1993 Provides Interim Guidance to Regions for Review of Licensee Action to Address Pressure Locking & Thermal Binding of Valves Until New Generic Communication Issued ML20058G5601993-11-30030 November 1993 Notification of 931206 Meeting W/Util in Rockville,Md to Discuss Licensee 931021 Request to Be Allowed to Use Alternatives to Requirements of 10CFR50.55a(f) & (G) ML20057B1281993-09-14014 September 1993 Forwards Page 33 of Rev 5 to GGNS Training & Qualification Plan,Transmitted Via .Page Inadvertently Omitted from Subj Transmittal.Page Withheld ML20057A4581993-09-0101 September 1993 Notification of Significant Meeting W/Util in Atlanta,Ga on 930916 to Discuss Refueling Outage Number 6 Plan & Current Plant Issues 1999-09-02
[Table view] Category:MEMORANDUMS-CORRESPONDENCE
MONTHYEARML20217M6061999-10-20020 October 1999 Notification of 991102 Meeting with Util in Port Gibson,Ms to Discuss Bases for Emergency Preparedness Plan Change Submitted in & Supplemented by 990120 & 0715 Ltrs IR 05000416/19990021999-09-10010 September 1999 Notification of Significant Licensee Meeting with Entergy Operations,Inc on 991018 to Discuss Listed Topics Identified in NRC Insp Repts 50-416/99-02,99-03 & 99-06 ML20211K7171999-09-0202 September 1999 Forwards Ineel Technical Ltr Rept, Evaluation of Fuel Pin Failure Timing in Boiling Water Reactors Dated 990730.Rept Used for Review of BWROG Rept on Revised Source Term Accident Analysis ML20211H4441999-08-27027 August 1999 Notification of Significant Meeting with Util on 990916 & 17 in Arlington,Tx to Improve Utility & NRC Understanding of Industry & Regulatory Perspectives on Current Issues ML20209G2421999-07-14014 July 1999 Notification of 990722 Meeting with License in Rockville, MD to Discuss Changes in EOI Licensing Organization Including Division of Responsibilities within New EOI Corporate Licensing Group ML20196F0391999-06-23023 June 1999 Notification of 990707 & 08 Meeting with EOI in Conference 1 at GGNS Energy Svc Ctr to Discuss Low Power Shutdown Risk Assessment Methods & Associated Probabilistic Risk Assessment Model ML20207A2551999-05-18018 May 1999 Notification of 990603 Meeting with EOI in Rockville,Md to Discuss EOI Submittal on BWROG Source Term Analysis & Possible Related Future Amend Requests from EOI ML20205R8871999-04-20020 April 1999 Notification of 990504 Meeting with Util in Rockville,Md to Discuss Proposal to Submit Consolidated Security Plan for Util Sites ML20205B8871999-03-26026 March 1999 Notification of 990415 Meeting with Utils in Knoxville,Tn to Visit Test Site & Discuss Test Program for ECCS Suppression Pool Suction Strainer.Context of Meeting Considered Entirely Proprietary ML20204B3041999-03-15015 March 1999 Notification of Licensee Meeting with Util in Energy Svc Ctr,Grand Gulf Site on 990415 to Discuss Plant Performance Review Results.Meeting Open to Public ML20195G1121998-11-17017 November 1998 Notification of 981201-02 Meeting with Entergy Operations in Taft,Louisianna to Conduct Joint Workshop for Licensing Personnel from Entergy & Nrc,Project Directorate IV-1 ML20151X1651998-09-14014 September 1998 Notification of Significant Licensee Meeting W/Util on 980929 to Discuss Emergency Preparedness Activities & Issues ML20151U7971998-09-0808 September 1998 Notifies of 980929 Meeting with Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring Quality Assurance Plan Details from Current Program Plans at Four Sites to Std Quality Assurance Program Plan ML20153H6671998-09-0808 September 1998 Revised Notification of 981007 Meeting with Util to Discuss Level of Instructions & Details for Transferring QA Plan Details from Current Program Plans at Four Sites to Std Program Plan at All Sites.Originally Scheduled for 980929 ML20238F5861998-08-28028 August 1998 Notification of 980909 Meeting w/BWR/6S:EOI & Listed Utils in Rockville,Md to Discuss W/Nrc Planned Applications by Licensees to Reduce Operability Requirements During Refueling Outages ML20237A2811998-08-12012 August 1998 Notification of 980827 Meeting W/Nrc & Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring QA Plan Details from Current Program Plans at Four Sites ML20249A2101998-06-11011 June 1998 Notification of 980702 Meeting W/Util in Rockville,Md to Discuss Level of Instructions & Details for Transferring Quality Assurance Plan Details from Current Program Plans at Four Sites to Std Quality Assurance Program Plan for Site ML20248M0751998-06-0909 June 1998 Notification of 980625 Meeting W/Util in Rockville,Md to Discuss Installation & Design of Suppression Pool ECCS Strainer to Meet NRC Bulletin 96-003 ML20248B4181998-05-26026 May 1998 Forwards NRC Operator Licensing Exam Rept (Including Completed & Graded Tests) for Tests Administered on 980330- 0403 IR 05000416/19983011998-05-26026 May 1998 Forwards NRC Operator Licensing Exam Rept 50-416/98-301 for Tests Administered on 980330-0403 ML20216D6351998-04-13013 April 1998 Notification of 980416 Meeting W/Util in Rockville,Md to Discuss Entergy Operations,Inc Initial Proposal to Standardize Security Plans for Listed Plants ML20217E8471998-03-26026 March 1998 Notification of Significant Licensee Meeting W/Util on 980402 to Discuss Entergy Operations,Inc Annual Performance Assessment ML20216H9441998-03-19019 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md for Licensee to Brief Staff on Risk Mgt for Upcoming 9th Refueling Outage Scheduled to Begin on 980411.Licensee Will Do Presentation to Meet NRC Bulletin 96-003 ML20216J4051998-03-18018 March 1998 Forwards SER Authorizing Licensee 980211 & 0310 Ltrs, Requesting Approval of Alternative Reactor Weld Exam,Per Provisions of 10CFR50.55a(a)(3)(i) & 10CFR50.55a(g)(6)(ii) for Plant for Next 2 Operating Cycles ML20217F2521998-03-11011 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md to Discuss Design of Suppression Pool Strainer to Meet NRC Bulletin 96-003.Meeting Cancelled as of 980326 ML20216C8601998-03-11011 March 1998 Notification of 980331 Meeting W/Util in Rockville,Md to Discuss Design of Suppression Pool Strainer to Meet Bulletin 96-03 ML20197B8721998-03-0505 March 1998 Notification of 980401 Meeting W/Util in Jackson,Ms to Discuss Licensing Issues & Regulatory Performance Efficiencies W/Licensing Staff for Plants.Meeting Agenda Encl ML20203B4131998-02-0505 February 1998 Notification of 980319 Meeting W/Entergy Operations,Inc,In Rockville,Md to Discuss Level of Instructions & Details of Transferring QA Plan Details from Current Program Plans at Four Sites to Standard QA Program Plan for Use at All Sites ML20198M8351998-01-12012 January 1998 Notification of 980122 Meeting W/Util in Rockville,Md to Discuss Site Licensing Status for Listed Plants & to Explore Ways to Standardize Licensing Submittals & Issuances ML20198M7531998-01-12012 January 1998 Notification of Meeting W/Entergy Operations,Inc,On 980123 in Rockville,Md to Discuss Plans to Change Radiological Emergency Response Plan ML20198K0791997-10-15015 October 1997 Notification of 971022 Meeting W/Entergy Operations,Inc in Rockville,Md Re Standard Quality Assurance Manual for Entergy Sites ML20217D0461997-09-29029 September 1997 Notification of Significant Licensee Meeting W/Util on 971029 to Discuss Systematic Assessment of Licensee Performance ML20141E8501997-06-27027 June 1997 Notifies of 970710 Meeting W/Licensee in Rockville,Md Re Appeal of Decision by Nrc,In ,That Changes in Rev 28.001-95 of Plant Emergency Plan Not within 10CFR50.54(q) & Can Not Be Implemented W/O Prior NRC Approval ML20137W6841997-04-15015 April 1997 Notification of 970502 Meeting W/Listed Attendees in Jackson,Mi.Meeting Agenda Encl ML20137F2351997-03-24024 March 1997 Summary of 970207 Meeting W/Listed Attendees in Rockville,Md to Discuss Nuclear Energy Inst Concerns Re Graded Quality Assurance Activities W/Volunteer Plants ML20137C9201997-03-20020 March 1997 Forwards Documentation of Meeting Conducted in Region 4 Office on 970225 to Discuss NRC Enforcement Policy as Applied to Nonescalated Enforcement ML20135F8581997-03-13013 March 1997 Notification of 970424 Licensee Meeting W/Util in Arlington, Tx to Discuss Current Performance ML20135F0921997-03-0606 March 1997 Notification of Significant Licensee Meeting W/Util on 970319 to Discuss Current Performance.Meeting Cancelled ML20135D8531997-03-0303 March 1997 Notification of 970325 Meeting W/Util in Port Gibson,Ms to Discuss MOV Thurst Methodology Developed by Util.Subj Methodology Being Applied in Licensee Response to GL 95-07 ML20135D7791997-02-27027 February 1997 Notification of Significant Licensee Meeting W/Entergy Operations,Inc on 970319 in Arlington,Tx to Discuss Current Performance ML20134M2471997-02-14014 February 1997 Submits List of Plants Not Meeting Selection Criteria for Ti 2515/118 Insp on Basis of Factors Such as SWS Operating Experience,Contribution of SWS to Plant Risk Assessment, Licensee Programs in Response to GL-89-13 ML20135B6231996-11-27027 November 1996 Notification of 961217 Licensee Meeting W/Util in Arlington, Tx to Discuss Evaluation Approach & Results of UFSAR Assessments at Each Facility ML20134L6121996-11-19019 November 1996 Notification of 961121 Meeting W/Entergy Operations,Inc,In Rockville,Md to Discuss Views on Funding for Decommissioning Costs of Nuclear Power Plants as May Apply for Each of Four Nuclear Plant Sites ML20129K1821996-11-0606 November 1996 Notification of 961121 Visit to Plant to Review Component Procurement Packages Using Graded Quality Assurance That Have Been Completed by Licensee ML20134C9121996-10-0808 October 1996 Notification of 961114 Meeting W/Util in Rockville,Md to Discuss Results of Self Assessment of Accuracy of Info in FSAR for Each Plant Site ML20134B5061994-04-13013 April 1994 Submits Plants Which Will Be Discussed in Categories Indicated Re Results of Screening Meetings for June 1994. Partially Deleted ML20149D7871993-12-20020 December 1993 Provides Interim Guidance to Regions for Review of Licensee Action to Address Pressure Locking & Thermal Binding of Valves Until New Generic Communication Issued ML20058G5601993-11-30030 November 1993 Notification of 931206 Meeting W/Util in Rockville,Md to Discuss Licensee 931021 Request to Be Allowed to Use Alternatives to Requirements of 10CFR50.55a(f) & (G) ML20057B1281993-09-14014 September 1993 Forwards Page 33 of Rev 5 to GGNS Training & Qualification Plan,Transmitted Via .Page Inadvertently Omitted from Subj Transmittal.Page Withheld ML20057A4581993-09-0101 September 1993 Notification of Significant Meeting W/Util in Atlanta,Ga on 930916 to Discuss Refueling Outage Number 6 Plan & Current Plant Issues 1999-09-02
[Table view] |
Text
l DISTRIBUTIO" l g Docket File WR Butlcr RP Reading J. Stoir
^ Local Reading R. Ireland
~I' G. Lainus R. Clark yy 3 3 g R. Tedesco V. Stello J. Hendrie T. Novak W. Haass W. .Minne rr RS Boyd R. Cudl 4 (
Voss A. lioore, Assie tant Di rec tor for Boiling WaIlir Ye'a'clors, L . shy niRU: Walter R. Butler, Chief. Boiling Water Reactors Branch 1,"L M8 8"E CONSIDEP/,TIO.i W IFil'r10 GEN GENET!ATION FRQ1 METAL-WATER REACTION - i!ARX III CLTIAINMENT SlMMARY The Staff has made the decision
- that the new G.E. product line, BkR/6 Reactor - Mark III Ceataiment, will be required to meet the coebustible nos centrol provisions of Safety Guide 7. This Safety Guide prevides certain limitations en hydrocen and oxygen concentrations in the contelrt'ent to prevent a combustible mixture of these two gases, and specifies that the sh or t- te rt.-
hydrogen release shuuld be based on 5% of the zircaloy fuel cladding reactim.;
with water. As described in an amendment to the PSAR for the Grand Gulf application tne t ark III Contattraent design has been changed to cceply with Safety Guide 7. IMuever, the design basis for hydrogen evolution contains certain assuruptions as to the rate at which the metal-water reaction proceeds.
(Safety Guide 7 does not address metal-water reaction rate censiderations.)
No decision has yet been rade by the Staf f in regard to the acceptability of this desi;n nasic for establishing the time rate of metal-water reaction and the resultin;; flew of hydrogen out of the pressure vessel. Ue are concerned that further delay in decemining the acceptability of the hydrogen evolution design basis could effect the Grand Gulf review schedule.
_DI S CUS SI O.11
^
In the Mark III Gontainment design, as incorporated in the Gran t Gulf applien-tion, short-tetr cen.bustiole s;as control is accomplished by providing a ferced circulattun system thich mixes the dryvell atmosphere ( 2P.0.000 Co. ft.)
! with the lara,er containment voltce ( 1,400,000 Cu. Ft.). 'the volume of the l drywell is insufficient to maintain the hydrogen concentratiun below the level of frtr per cent. as specified in Safety Guide 7. 11owever, the total volure of the centairment and the dryvell is suf ficient to dilute the potentiel i hy drogen released f ros a 5". metal-water reaction to an acceptable level.
In previous BWR containment designs an inerted atmosphere is relied en te l prevent a combustible mixture; the Mark III Contaircent cannot be inerted j primarily because personnel access into the containment is recessary duelug l normal operation. The tir.e rate of hydrogen relecse from the retal-vater i
- "Safety Evaluation by the Directorate of Licensing, US AEC, in the tatter of General Electric Company Mark III Containment Concept," issued 10/ 5/72.
= -. - - - - - ..
1
, 1 1
~ "' ^- -**- -
8806160125 000606
' '~ ~
PDR FOIA CONNOR GB-91 PDR
'"~
N30 :
lI ;
Voss A. Moore t reaction in en inerted containment has no effect on the desiqu requiremente.
However, in the bark III containment, atmosphere mixing must be delayed until the "blow-down" is co=pleted and the energy in the drywell is reduced to an acceptably low level to avoid over-pressurization and excesnive temperatures in the contaiment when acrosphere mixing (which bypasses the suppression pool) is initiated. Thus the r axium time rate of hydrogen generation must be nefined so that the containment cea be designed to meet the requirements for both energy s'appressicn and atmosphere mixing.
In amendments to the Grand Gulf application MP&L has proposed a particular design basis and calculational model, developed by G.E., for csiculating the caximud rate of hyriregen evolution. Briefly, the assumption is 'nade in the model that the peak clad temperatu:e following a LOCA goes ir.nediately to 2300 F and stays at that temperature indefinitely. The resulting hydrogen evolution rate is calculated using the procedure given in the G.E. Topical Report FEDO-11013-77, "An Analytical Procedure For the Conservative Calculation of Core betal-;iater Reaction Following a Design Basis Loss-of-Coolant Accident",
dated May, 1972. It should be noted that no mechanistic rationale has been suggested to support this 2300 F assumption. The originally submitted centainment design has been ciodified to maintain the hydrogen concentration
. (as calculated from this nedel) within the Safety Guide 7 limits. Using this m3 del for the Grand Gulf design the calculated hydrogen concentration in the drywell reachen the combustible gas control limit in about one hcur. Then, the atmosphere mixing and energy suppression features of the containment are designed assuming that atmosphere mixing between the drywell and the containment to control the hydrogen concentration will not be initiated entil af ter a significant f raction nf an h1ur elapses frcs:rthe time of the desi<;n basis LOCA. j 1
Although the staff has completed the first round review of the centainment I design and has issued appropriate questiers to HP&L, the responsible Branch, Con ta inre n t Sys tems, has stated that they ne continuing their "review of the .. . codelim; to include a time dependent metal-water rea : tion rate suitable to me ict the provisions of Safety Guide 7." In a recent dig cussion on this uatter G. Lainus stated that a decision on an accepte51e hydrogen generation basis had not yet been made but he, assured us ennt if the applicant l were preceeding down the "wrong path" in their contaiteent design he would have i so informed Re.getor Projects. Although this assurance by Leinus is helpful, a firm and definitive Staff position is needed. MP&L and the prospective
~
BWR/6 - Mark III applicants are expending considerable resources in developing l designs based on this prenosed basis and model. We believe further dela y in l formulating a firm policy not only could affect the Grand Gulf reviev schedule
-- - m --- = ~ -- . . _ __ x . __ -
l c
L
), -. - _
1 a
1 Voss A. Itoore but reduces the Staf f's flexibility to issue an independent judge'1ent shich might result in a si>;nificantly different hydrogen evolution c'esinn basis tlian the basis giveu in clie Grand Gulf application.
Higher management attention needs to b. focused on this key decision to reduce the possibility that significant redesigu will be required or that our review of the ': rand Gulf application might be delayed. If 3cu scree that it is appropriate and uculd be useful in expediting a decision, I will arrange a meeting betreen IP & RP i'ersonnel to discuss the current statue of the problem and, impefully, to establish a schedule for reachinr, a (tem staff pesition in this rate.er.
Ori.daal kned by G e rni.1 0 .ui.r-Getald F. Owsley, Project P.anager Boiliur; t,'ater Reactor Branch 1 D'.sectorate of Licensing I
l l
l 1
1 i
1 crnet > .L:NR ,1. .. l. ..L.g WS,.l.. .. . . . . . . . . . . . . . . . . . . . . . . . ..... .. . . . . . . .
Ujil ; C/ . . v sur.wr > .g . M. J .'ey.:.Ln
..,...L R.v e l.e r.. . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . .
%rr > l 5/ 2.3/ 7 3. 2
. 5M i .7.3 . . ..... . . . . . . . . . . . . . . . . . . . . . . . . _ . . . . . . . .
- . _ _ - _ . ._. _ __ _ . _