ML070660114
| ML070660114 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 02/23/2007 |
| From: | Chin R Duxbury Nuclear Advisory Committee/Pilgrim Watch |
| To: | NRC/ADM/DAS/RDB |
| References | |
| 71FR75280 00006, NUREG-1437 | |
| Download: ML070660114 (8) | |
Text
rage I OT .5 Doris Mendiola - EIS Statement - Pilgrim's Re-licensing Application From: "Rebecca Chin" <rebeccajchin@hotmail.com>
To: <PilgrimEIS@nrc.gov> // ,
Date: 02/23/2007 12:57 PM
Subject:
EIS Statement - Pilgrim's Re-licensing Application Please find additional comments below and in attachment as to my oral presentation, January 24, 2007, in Plymouth, MA.
Please acknowledge receipt of this statement.
Rebecca J. Chin - rebeccaichin @hotmail.com 31 Deerpath Trail North Duxbury, MA 02332 Rebecca Chin - Vice-Chair - Duxbury Nuclear Advisory Committee NUREG 1437 supplement 29, Draft NRC's Draft SEIS is inadequate in that the NRC staff mistakenly concluded the Applicant's SAMA Analysis was "sound." The SAMA analysis was faulty in that Entergy entered partial and selective data into the model and thereby underestimated consequences to make mitigation alternatives, such as the Direct Torus Vent System, appear not cost effective The purpose of a SAMA review is to ensure that any plant changes that have a potential for significantly improving severe accident safety performance are properly analyzed identified and addressed. One example of how a poorly performed SAMA analysis can lead to erroneous conclusions is the Pilgrim Environmental Report's look at the costs and benefits of installing a Direct Torus Vent filter at Pilgrim.
The Direct Torus Vent System (DTVS) is a method to relieve the high pressure which is generated during a severe accident.
In 1986, it was determined that the Mark I containment, especially being smaller with lower design pressure, in spite of the suppression pool, has a 90% probability of that containment failing. The purpose of the containment is to provide a barrier between the lethal radiation inside the reactor and the public. In order to protect the Mark I containment from a total rupture it was determined necessary to vent high pressure buildup. As a result, the "Direct Torus Vent System" at all Mark I reactors, including Pilgrim, was installed. Operated from the control room, the vent is a reinforced pipe installed in the torus and designed to release radioactive high pressure steam generated in a severe accident by allowing the unfiltered release directly to the atmosphere through the 300 foot vent stack. Use of the vent discharges steam and radioactive material directly to the atmosphere bypassing the standby gas treatment system (SBGTS) filters normally used to process releases via the containment ventilation pathway. There is no radiation monitor on the pipe and valves that comprise the DTV line. Operators now have the option by direct action to expose the public and the environment to unknown amounts of harmful radiation As a result of Pilgrim's design deficiency, the original idea for a passive containment system has been dangerously compromised and given over to human control with all its associated risks of error and technical failure.
There appears to be an internal contradiction in what we are being told. "The NRC believes that the release from a severe core-melt accident would be reduced [by the suppression pool] by a factor of one hundred. This is considerably more optimistic than estimated in the NRC's first study on the subject. Also, file://C:\temp\GW }00001 .HTM 02/27/2007
rage L o0 i the contention is that the reduction by a filtration system would have zero benefit. Here the contenders seem to be assuming that a factor of one hundred equals 100%. That is false. Even a release of 1 percent of the core's radioactive iodine and cesium would be a very severe event.
In its Environmental Report, Entergy analyzes the benefits of installing a filter to the torus vent in the course of reviewing possible severe accident mitigation alternatives.
Their Report states, this analysis case was used to evaluate the change in plant risk from installing a filtered containment vent to provide fission product scrubbing. A bounding analysis was performed by reducing the successful torus venting accident progression source terms by a factor of 2 to reflect the additional filtered capability. Reducing the releases from the vent path resulted in no benefit." The Report then states, "Basis for
Conclusion:
Successful torus venting accident progressions source terms are reduced by a factor of 2 to reflect the additional filtered capability. The cost of implementing SAMA at Peach Bottom was estimated to be $3 million. Therefore this SAMA is not cost effective for [Pilgrim]."
Entergy has determined that in return for a cost of $3 million, there will be no benefit to public health and safety.
How it is possible to find zero benefit from installing a filter that would reduce by a factor of two the radioactive venting to the public in the case of a severe accident?
Unfiltered venting has been judged unsafe by all regulatory agencies outside the United States. In its analysis of several risk contributors to Core Damage Frequency, the disposition of those events frequently included "venting via DTV path to reduce containment pressure." In other words, a filter in the torus vent could reduce the impact in many possible severe accidents. The only conclusion to draw from the outcome of the DTV filter SAMA analysis is that, Entergy has used the MACCS2 code to downplay the health and economic costs of severe accidents and used the Probabilistic Safety Analysis (PSA) model to make the benefits of mitigation appear to be zero.
NRC staff reviewed Entergy's analysis and concluded that the methods used and implementation of those methods was sound. And "the costs of SAMAs evaluated would be higher than the associated benefits.
5.2.5. The NRC staff is wrong to accept Entergy's SAMA analysis in the application.
The SAMA analysis included in the Pilgrim Environmental Report is incomplete.
Not only does the probabilistic modeling for severe accidents artificially make consequences appear insignificant, but the Applicant has used incomplete and incorrect input parameters into the MACCS2 code.
The direct torus vent filter as an example of how this cost benefit equation might have been skewed in favor of no mitigation "While NEPA does not require agencies to select particular options, it is intended to
'foster both informed decision-making and informed public participation, and thus to ensure the agency does not act upon incomplete information, only to regret its decision after it is too late to correct' It then said "if 'further analysis' is called for, that in itself is a valid and meaningful remedy under NEPA." The Applicant has drastically under counted the costs of a severe accident, and this could have led it to erroneously reject mitigation alternatives. Further analysis is called for.
EPA has acceptable standards for exposure, in the real world; there is no safe level of exposure to radiation.
In conclusion, the danger of NRC rubber stamping Entergy's SAMA in the Draft SEIS - accepting the licensee's minimization of consequences that make the cost of adding a filter to the Direct Torus Vent seem unnecessarily high/ not cost effective when it is obvious that the mitigation of installing the filter could indeed serve to protect public health and safety. I repeat, unfiltered venting has been judged unsafe by all regulatory agencies outside the United States.
Generic Environmental Impact Statement for License Renewal of Nuclear Plants Draft Report for Comment- NUREG 1437 supplement 29: Appendix G: Table G-4 SAMA Cost/Benefit Screening file://C:\temp\GW }00001 .HTM 02/27/2007
rage -) or )
Analysis for PNPS:
cost benefit now stated at $1,220,000 Clearly, the Applicant's first analysis wasn't sound and it is equally clear that the second analysis is not sound - both are perfect examples of how a poorly performed SAMA analysis can lead to an erroneous conclusion. The Applicant used incomplete and incorrect input parameters into the MACCS2 code to downplay the health and economic costs of severe accidents and used the Probabilistic Safety Analysis model to limit the benefits of mitigation. It ignored the true off-site radiological and economic consequences of a severe accident at Pilgrim. The Applicant did not fully consider the alternatives that could mitigate consequences including atmospheric releases, fallout onto open bodies of water, releases to ground water, and societal and economic impacts. The regulations require a broad assessment of mitigation not an easy dismissal by "probability weighting." Probabilistic modeling can underestimate the true consequences of a severe accident. The user has total control over the results that will be produced using the MACCS2 Code. Neither the MACCS2 model used to analyze consequence nor the input data provided by the applicant provide an accurate assessment of the off-site dose and economic consequences of a severe accident. Entergy's input to the code, including meteorological data, demographics, emergency response, and regional economic data, were incomplete, incorrect or out of date. These inaccuracies result in incorrect conclusions drawn about accident consequences and minimize the likely risks of a severe accident. The Applicant has drastically under counted the costs of a severe accident, and this could have led it to erroneously reject mitigation alternatives. Further analysis is called for.
It would make no sense for the NRC to require Severe Accident Mitigation Analysis if an Applicant could simply multiply all consequences of an accident by extremely low probability and thus reject all possible mitigation as too costly. The NRC ruled that all testimony on accident consequences must also contain a discussion of accident probabilities. The Commission should not ignore the potential consequences of severe-consequence accidents by always multiplying those consequences by low probability values."
I challenge the Applicant's subsequent second try. It is just as likely the revised number is no more accurate and a gross under estimation. I have not changed my conclusion that the licensee is significantly minimizing the consequences of unfiltered venting. The NRC treats most environmental issues as generic so how then is it fair or reasonable to say $3 million at one reactor is cost effective and here it is not? Look at the value of just the Town of Duxbury's 19,082 acres of aquaculture/shell fishing annual multi million dollar industries; 870.46 acres of Cranberry Bogs yielding $1 million annually, homes, property and businesses assessed at $3,668,240,970. The $3 million cost is a small price to better protect public health and safety file://C:\temp\GW }00001 .HTM 02/27/2007
Rebecca Chin - Vice-Chair - Duxbury Nuclear Advisory Committee NUREG 1437 supplement 29 NRC's Draft SEIS is inadequate in that the NRC staff mistakenly concluded the Applicant's SAMA Analysis was "sound." The SAMA analysis was faulty in that Entergy entered partial and selective data into the model and thereby underestimated consequences to make mitigation alternatives, such as the Direct Torus Vent System, appear not cost effective The purpose of a SAMA review is to ensure that any plant changes that have a potential for significantly improving severe accident safety performance are properly analyzed identified and addressed. One example of how a poorly performed SAMA analysis can lead to erroneous conclusions is the Pilgrim Environmental Report's look at the costs and benefits of installing a Direct Torus Vent filter at Pilgrim.
The Direct Torus Vent System (DTVS) is a method to relieve the high pressure which is generated during a severe accident.
In 1986, it was determined that the Mark I containment, especially being smaller with lower design pressure, in spite of the suppression pool, has a 90%
probability of that containment failing. The purpose of the containment is to provide a barrier between the lethal radiation inside the reactor and the public. In order to protect the Mark I containment from a total rupture it was determined necessary to vent high pressure buildup. As a result, the "Direct Torus Vent System" at all Mark I reactors, including Pilgrim, was installed. Operated from the control room, the vent is a reinforced pipe installed in the torus and designed to release radioactive high pressure steam generated in a severe accident by allowing the unfiltered release directly to the atmosphere through the 300 foot vent stack. Use of the vent discharges steam and radioactive material directly to the atmosphere bypassing the standby gas treatment system (SBGTS) filters normally used to process releases via the containment ventilation pathway.
There is no radiation monitor on the pipe and valves that comprise the DTV line.
Operators now have the option by direct action to expose the public and the environment to unknown amounts of harmful radiation As a result of Pilgrim's design deficiency, the original idea for a passive containment system has been dangerously compromised and given over to human control with all its associated risks of error and technical failure.
There appears to be an internal contradiction in what we are being told. "The NRC believes that the release from a severe core-melt accident would be reduced [by the suppression pool] by a factor of one hundred. This is considerably more optimistic than estimated in the NRC's first study on the subject. Also, the contention is that the reduction by a filtration system would have zero benefit. Here the contenders seem to be assuming that a factor of one hundred equals 100%. That is false. Even a release of 1 percent of the core's radioactive iodine and cesium would be a very severe event.
In its Environmental Report, Entergy analyzes the benefits of installing a filter to the torus vent in the course of reviewing possible severe accident mitigation alternatives.
Their Report states, this analysis case was used to evaluate the change in plant risk from installing a filtered containment vent to provide fission product scrubbing. A bounding analysis was performed by reducing the successful torus venting accident progression source terms by a factor of 2 to reflect the additional filtered capability. Reducing the releases from the vent path resulted in no benefit." The Report then states, "Basis for
Conclusion:
Successful torus venting accident progressions source terms are reduced by a factor of 2 to reflect the additional filtered capability. The cost of implementing SAMA at Peach Bottom was estimated to be $3 million. Therefore this SAMA is not cost effective for [Pilgrim]." Entergy has determined that in return for a cost of $3 million, there will be no benefit to public health and safety.
How it is possible to find zero benefit from installing a filter that would reduce by a factor of two the radioactive venting to the public in the case of a severe accident?
Unfiltered venting has been judged unsafe by all regulatory agencies outside the United States. In its analysis of several risk contributors to Core Damage Frequency, the disposition of those events frequently included "venting via DTV path to reduce containment pressure." In other words, a filter in the torus vent could reduce the impact in many possible severe accidents. The only conclusion to draw from the outcome of the DTV filter SAMA analysis is that, Entergy has used the MACCS2 code to downplay the health and economic costs of severe accidents and used the Probabilistic Safety Analysis (PSA) model to make the benefits of mitigation appear to be zero.
NRC staff reviewed Entergy's analysis and concluded that the methods used and implementation of those methods was sound. And "the costs of SAMAs evaluated would be higher than the associated benefits. 5.2.5. The NRC staff is wrong to accept Entergy's SAMA analysis in the application.
The SAMA analysis included in the Pilgrim Environmental Report is incomplete.
Not only does the probabilistic modeling for severe accidents artificially make consequences appear insignificant, but the Applicant has used incomplete and incorrect input parameters into the MACCS2 code.
The direct torus vent filter as an example of how this cost benefit equation might have been skewed in favor of no mitigation "While NEPA does not require agencies to select particular options, it is intended to 'foster both informed decision-making and informed public participation, and thus to ensure the agency does not act upon incomplete information, only to regret its decision after it is too late to correct' It then said "if 'further analysis' is called for, that in itself is a valid and meaningful remedy under NEPA." The Applicant has drastically under
counted the costs of a severe accident, and this could have led it to erroneously reject mitigation alternatives. Further analysis is called for.
EPA has acceptable standards for exposure, in the real world; there is no safe level of exposure to radiation.
In conclusion, the danger of NRC rubber stamping Entergy's SAMA in the Draft SEIS - accepting the licensee's minimization of consequences that make the cost of adding a filter to the Direct Torus Vent seem unnecessarily high/ not cost effective when it is obvious that the mitigation of installing the filter could indeed serve to protect public health and safety. I repeat, unfiltered venting has been judged unsafe by all regulatory agencies outside the United States.
Generic Environmental Impact Statement for License Renewal of Nuclear Plants Draft Report for Comment- NUREG 1437 supplement 29: Appendix G: Table G-4 SAMA Cost/Benefit Screening Analysis for PNPS:
cost benefit now stated at $1,220,000 Clearly, the Applicant's first analysis wasn't sound and it is equally clear that the second analysis is not sound - both are perfect examples of how a poorly performed SAMA analysis can lead to an erroneous conclusion. The Applicant used incomplete and incorrect input parameters into the MACCS2 code to downplay the health and economic costs of severe accidents and used the Probabilistic Safety Analysis model to limit the benefits of mitigation. It ignored the true off-site radiological and economic consequences of a severe accident at Pilgrim. The Applicant did not fully consider the alternatives that could mitigate consequences including atmospheric releases, fallout onto open bodies of water, releases to ground water, and societal and economic impacts. The regulations require a broad assessment of mitigation not an easy dismissal by "probability weighting." Probabilistic modeling can underestimate the true consequences of a severe accident. The user has total control over the results that will be produced using the MACCS2 Code. Neither the MACCS2 model used to analyze consequence nor the input data provided by the applicant provide an accurate assessment of the off-site dose and economic consequences of a severe accident. Entergy's input to the code, including meteorological data, demographics, emergency response, and regional economic data, were incomplete, incorrect or out of date. These inaccuracies result in incorrect conclusions drawn about accident consequences and minimize the likely risks of a severe accident. The Applicant has drastically under counted the costs of a severe accident, and this could have led it to erroneously reject mitigation alternatives. Further analysis is called for.
It would make no sense for the NRC to require Severe Accident Mitigation Analysis if an Applicant could simply multiply all consequences of an accident by extremely low probability and thus reject all possible mitigation as too costly. The NRC ruled that all testimony on accident consequences must also contain a discussion of accident probabilities. The Commission should not ignore the potential consequences of severe-consequence accidents by always multiplying those consequences by low probability values."
I challenge the Applicant's subsequent second try. It is just as likely the revised number is no more accurate and a gross under estimation. I have not changed my conclusion that the licensee is significantly minimizing the consequences of unfiltered venting. The NRC treats most environmental issues as generic so how then is it fair or reasonable to say $3 million at one reactor is cost effective and here it is not? Look at the value of just the Town of Duxbury's 19,082 acres of aquaculture/shell fishing annual multi million dollar industries; 870.46 acres of Cranberry Bogs yielding $1 million annually, homes, property and businesses assessed at $3,668,240,970. The $3million cost is a small price to better protect public health and safety
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EIS Statement - Pilgrim's Re-licensing Application Creation Date 02/23/2007 12:56:48 PM From: "Rebecca Chin" <rebeccajchin.@hotmail.com>
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