Letter Sequence Other |
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Results
- Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval, Approval
Other: ML19325E833, ML19327A643, ML19327A644, ML19327A651, ML19327A658, ML19327A660, ML19327A663, ML19327A664, ML19327A665, ML19327A666, ML19327A667, ML19327A670, ML19327A671, ML19327A672, ML19327A673, ML19327B596, ML19327B598
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MONTHYEARML19327B5951989-05-10010 May 1989
Safety Evaluation Accepting Util 860221 Proposed Amend to Licenses DPR-39 & DPR-48,revising Tech Specs to Limit Purge & Vent Valve Operation Above Cold Shutdown
Project stage: Approval
ML19327A6411989-05-10010 May 1989
Forwards Safety Evaluation Accepting Proposed Tech Spec Changes Re Purge/Vent Operation.Licensee Should Verify That Positive Stop Installed on Valve to Prevent Opening Beyond Tech Spec Angle
Project stage: Approval
ML19327A6611989-05-11011 May 1989
Discusses Differing Professional View Re Issuance of SER to Plant Allowing Full Power Operation W/Open 42 Containment Isolation Valves & Methodology Use for Calculating Related Offsite Doses
Project stage: Approval
ML19327B5881989-05-11011 May 1989
Safety Evaluation Concluding That 42-inch Containment Purge & Supply Valves Should Remain Closed in Modes l,2,3 & 4 Since Consequence of Offsite Dose to Thyroid from Iodine During LOCA Unacceptably High
Project stage: Approval
ML19327A6621989-05-11011 May 1989
Forwards SER Re Licensee Proposal Allowing Full Power Operation of Facility w/42 Inch Purge Supply & Exhaust Containment Isolation Valves
Project stage: Approval
ML19327A6431989-05-18018 May 1989
Ack Receipt of Containing Differing Prof Opinion Re Methodology Used for Calculating Related Offsite Doses. List of Persons to Be Considered as Third Member of Standing Review Panel Requested
Project stage: Other
ML19327A6441989-05-25025 May 1989
Submits List of Nominees for Third Member of Standing Review Panel,Per 890519 Request
Project stage: Other
ML19327A6661989-05-26026 May 1989
Forwards 890511 Memo Expressing Differing Professional View of B a Licciardo Re Containment Isolation Valves,For Review & Recommendation by J Miraglia
Project stage: Other
ML19327A6671989-06-0202 June 1989
Informs of Adequate Info Being Supplied to Initiate Review by SRP Re Differing Professional View
Project stage: Other
ML19327A6471989-06-23023 June 1989
Requests Notification of When Requested Info Re Containment Isolation Valves W/Regard to Fuel Failure for LOCA Analyses, Clarification of Mechanisms Used for Transporting Fission Products & View on Safety Significance Will Be Provided
Project stage: Approval
ML19327A6681989-06-30030 June 1989
Advises That Specific Issues Identified in 890623 Memo Would Be Further Clarified by 890717
Project stage: Approval
ML19327A6691989-07-14014 July 1989
Corrected Memo Advising That 890717 Submittal,Re Clarification of Differing Prof View,Will Be Provided on 890723
Project stage: Approval
ML19327A6701989-07-14014 July 1989
Advises That Info Provided by Memo Will Be Submitted by 890720
Project stage: Other
ML19327A6601989-07-20020 July 1989
Discusses Differing Professional View Re Plant Containment Isolation Valves
Project stage: Other
ML19327A6721989-07-20020 July 1989
Evaluation of Criteria for & Calculation of Offsite Doses Deriving from Open Containment Purge Valves During LOCA at Zion Units 1 & 2
Project stage: Other
ML19327A6711989-07-21021 July 1989
Notifies EDO of Status Re Differing Professional View Filed on 890511.Chronology Documents Status Encl
Project stage: Other
ML19327B5991989-07-27027 July 1989
Requests Listed Clarifying Info Supporting Standing Committee on Differing Prof Views (Dpv) Review of Licciardo Dpv Re Containment Isolation Valves at Plant.Info Requested by C.O.B. on 890727
Project stage: Approval
ML19327A6731989-08-10010 August 1989
Discusses Differential Professional View Re Plant Purge Operation
Project stage: Other
ML19327A6511989-08-10010 August 1989
Forwards N Lauben Memo Re Technical Issues Raised in Dpv Concerning Containment Isolation Valves at Facilities. Rupture of High Burnup Fuel Pins During Blowdown Transient Not Credible for Existing Fuel Designs
Project stage: Other
ML19327A6521989-08-10010 August 1989
Comments on Dpv Concerning Early Blowdown Cladding Rupture During Large Break Loca.Table Listing Gapcon Pin Pressure Calculations Encl
Project stage: Approval
ML19327A6631989-08-11011 August 1989
Discusses View on Purging Re Plant Containment Isolation Valves
Project stage: Other
ML19327A6571989-08-21021 August 1989
Forwards Comments on Differing Prof View Re Early Blowdown Cladding Rupture During Large Break Loca.Comments Address Issues Re Cladding Rupture of High Burnup High Pressure Fuel Early in Blowdown Prior to Containment Isolation
Project stage: Approval
ML19327B5981989-08-22022 August 1989
Advises of Apparent Fundamental Misunderstanding in Preparation of Document Contributing to Resolution of Differing Prof View Re Containment Isolation Valves at Plant,Per 890821 Telcon W/W Hodges
Project stage: Other
ML19327B5961989-08-22022 August 1989
Summarizes 890822 Telcon from Licciardo Re Matl Provided to Review Panel,By Nrc,Concerning Licciardo Differing Prof View on Containment Isolation Valves at Plant.Licciardo Asked to Provide Concerns in Written Form by C.O.B. on 890822
Project stage: Other
ML19327A6561989-08-23023 August 1989
Forwards Revised Comments from Gn Lauben on Differing Prof View Re Early Blowdown Cladding Rupture During Large Break Loca.Rupture of High Burnup Fuel Pins During Blowdown Transient Not Credible for Existing Fuel Designs
Project stage: Approval
ML19327A6641989-08-24024 August 1989
Advises That 890811 Note Providing Revised Analyses to Recognize Higher Linear Heat Generation Rates for Zion, Remain Unchanged
Project stage: Other
ML19327A6581989-08-25025 August 1989
Informs That Author Reviewed R Licciardo 890822 Memo to F Miraglia Re Adequacy of N Lauben Analysis of LOCA Using Low Burnup,Low Pressure Fuel & Which Have High LHGR than Analyzed by Lauben.Early Rupture of Fuel Pins Remains Valid
Project stage: Other
ML19327A6651989-08-29029 August 1989
Forwards Response to Question Addressed in 890822 Memo Re Containment Isolation Valves
Project stage: Other
ML19327A6931989-09-13013 September 1989
Lists Actions Needed to Be Taken Re Review of 890511 Differing Prof View,Including Issuance of Evaluation of Zion Tech Specs
Project stage: Approval
ML19327B5701989-09-19019 September 1989
Discusses R Licciardo 890511 Differing Prof Opinion.Action Requested Per Encl Murley 890913 Memo Directing NRC to Ensure That Pressure & Temp Effects During LOCA Cosidered in Review of New & Advanced Fuel Designs
Project stage: Approval
ML19325E8331989-10-31031 October 1989
Forwards Chronology Re R Licciardo Differing Prof View on Containment Isolation Valves at Plant.Encl 2 Is NRR Records Associated W/Differing Prof View.W/O Encl 2
Project stage: Other
1989-07-21
[Table View] |
Similar Documents at Zion |
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Text
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ENCLOSURE 3 1
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8/10/09 NOTE TO:
Ashok Thadani
- FROM:
Ted Quay
/
SUBJECT:
DPV CONCERNING ZION PURGE OPERATION Without going over each specific item in detail. Mr. Licciardo's DPV stems from hit misapplication of an instantaneous release of fission products to the containment (and to the environment) through the open purge valves.
The LOCA Regulatory Guides (1.3 and 1.4)'were intended to establish the source' term to be used for evaluation of -the containment design f eatures f or. mitigation of the radiological consequences of the LOCA.
The " Instantaneous" Source term used in accidents such as LOCA was established to ensure containment isolation features incorporated either f ast ' acting valves or f eatures that would ensure that containment integrity was not compromised during operation (e.g.,
dual doors on personnel t
locks).
Use of the instantaneous source term prevented a case-by-case analysis of each containment incorporating slow isolation features.
This simplified approach was never intended to be applied to purge valves except for those purge systems that incorporated-extremely slow closing valves.
No opening in containment could be justified using the instantaneous source term.
Consequently, no purge / vent system design could be found acceptable using a simplified instantaneous release assumption. Without purge vent capability plant operations would be tremendously restricted.
The SRP recognized the luck of realism of the " instantaneous" l
release assurrption and - established that 1) purge / vent systems heeded ex tremely f ast acting valves (and in most cases, this means air operated so that power failure results in closure without reliance on any ac/dc power source such as the diesels): and 2) a more realistic source term, maximizing the fission product content of the primary coolant during opeqational conditions, (spike i
l coolant activity for a PWR-60 uC1/gm) should be employed.
l A number of years ago, Limerick had a two inch " vent" line that l
had extremely slow acting isolation valves (closure time on the l'
order of two minutes).
NRC imposed the instantaneous source term on the evaluation of the doses from this line for two reasons. The first is that for a 2" line there is no reason 0.g1 to incorporate a fast acting valve.
Second, the risk from failure to isolate the I
containment increases the longer a line is left open due to LOCA produced debris.
The Zion DPV analysis argues that substantial l'
core damage occurs f ast.
The information provided by Wayne Hodges L
disputes this. Complete core damage does not occur instantaneously and even assuming the fast releases of substantial amounts of fission products, the DPV ignores orogression of fuel damage with hoatup and consequently, any transport time to the break.
The first pound of primary coolant released to the containment (and f or 1
8 % IM W2XA s
I
e 1
V l p.
that matter to the environment) is assumed to contain the same amount of fission products as a cound released from the primary system much later in the blowdown phase.
Taking this argument to the extreme, all the fission products would be released during the blowdown phase which in some cases could be as short as ten seconds.
Although the SRP specifies 5 seconds, (iEB accepted closure times up to 15 seconds based on inf ormal discussions we had with Research on their severe accident analyses.
We were told that even up to 20 seconds that no substantial releases would occur.
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