ML20058N471
| ML20058N471 | |
| Person / Time | |
|---|---|
| Issue date: | 07/26/1990 |
| From: | Carr K NRC COMMISSION (OCM) |
| To: | Geoffrey Miller HOUSE OF REP., INTERIOR & INSULAR AFFAIRS |
| Shared Package | |
| ML20055H726 | List: |
| References | |
| FRN-53FR49886, RULE-PR-CHP1 CCS, MILLER-900726, NUDOCS 9008140152 | |
| Download: ML20058N471 (6) | |
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..t QUESTION-14.
The Commission's letter of-June 29,'1990, states that the i
individual dose criterion for the BRC policy.was raised from 1 mrem per year to 10. mrem per year at the direction of.
Mr. Yictor Stello, who was Executive Director _ for Operations at the~ time this' change was madE to the-draf t BRC policy. The 1
letter states that Mr.'Stello, "... questioned whether the 4
proposed individual dose criterion value:of,1 mrem /yr would.
provide sufficient flexibility in practical. application of the i
poli cy. "
l Please provide a full explanation of Mr. Stello's objections to the 1 mrem /yr individual dose criterion and the rationale for.
increasing the individual dose criterion to 10 mrem /yr.
Please~
address the following questions lin your explanation:
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t At the time the individual dose criterion was raised to 10 mrem, did the Commission share Mr. Stello's concern that the l' mrem individual. dose criterion did-not " provide sufficient-flexibility?in practical
. application' of the policy?"
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Why would an individual-dose criterion of 1 mres/yr not " provide sufficient flexibility in practical 4
application of the policy?"
9008140152 900720 PDR COMMS NRCC CORRESPONDENCE PDC 1
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QUESTION 14.(Continued)
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Please identify what,lif any,' practices would be more likely to be exempted from regulation using h
the 10 mrem /yr criterion rather than; the ~ 1. mrem /yr.
criterion originally proposed by the NRC staff.
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ANSWEP:
As you are aware, Mr. Stello is presently unployea by the U.S. Department of _
Energy. We did not attempt to contact him to confirm the basis for his preference for the 10 mrem / year criterico.
Based on our understanding.of the discussions surrounding the decision to increase the individual-dose criterion from 1 to 10 mrem /yr, a 10 mrem /yr criterion was selected-for-several reasons.
l It ensures a safe and consistent level:of protection for the_public.
It is more consistent with dose levels previously _ established for site cleanup and _
decommissioning projects and it is feasible for implementation in these applications. -In addition, ti.s cost of dose reductions below 10 mrem /yr may not be connensurate with the corresponding reduction in risk.
i At the time the decisior, was made in July and-August-of 1988, the staff had i
developed a graded approach to guide regulatory exemption decisions, including -
three individual dose levels at.100,10, and 1 mrem / year. This' approach was based on the fundamental concept that the-rigor of analyses required to i
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.l OVESTION14.(Continued),
3-l support an exemption would be reduced proportionally as the individual dose' decreases.
Between 100 and 10 millirem / year, exemptions would have to be supported by a demonstration that both the individual and collective doses 1
Below 1 mrem / year, the demonstration were as-low as reasonably-achievable.
r would be considerably less demanding provided that'the collective dose was below 100 or 1000 person-rem / year (both. levels were considered in developing thepolicy). Exemptions between 10 and 1 mrem / year would require an intermediate level of support.
The'10 mrem / year criterion appeared to be the more appropriate value for~ the l
individual dose criterion because the distinction between exemptions at the 10 and-1 mrem / year level could not be, justified on a health and safety basis.
The icvel of effort required to review analyses of dose reductions below 10 mrem / year would not be balanced by the resulting decrease in risk considering the limited number of people who might be exposed, let alone.the' effort L
required to assess the potential dose reductions and the actual implementation-of the dose reduction features, i
l-L In addition, at the time the 10 mrem / year criterion was selected, staff-l considered-that a 10 mrem / year level _would be more consistent with ct ' rent practices involving'the safe releases of radioactive materials to.thi i
environment. For example, the 10 mrem / year-value was generally _ consistent!
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with effluent-release guidance established by the NRC in 10 CFR.Part 50, i
Appendix I for nuclear power reactor effluents, which was supported by a rigorous cost-benefit analysis. The 10 mrem / year-level was also consistent.
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QUESTION 14..(Continued) -
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with cleanup levels used in decomissioning projects,- such as the 5' microRoentgen/ hour level established for cleanup of reactor. components containing gasuna-emitting radionuclides (e.g.,~ Cobalt-60).
Furthermore, it was unclear whether cleanup: levels based on an individual' dose criterion of I mrem / year could be reasonably imposed on.decomissioning
- projects because of technological limitations-in the onsit'e detection and L
. implementation of such low levels, difficulties in distinguish'ing these low F
. levels from natural-background, large uncertainties associated with:the health
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significance of these levels, and the large. incremental increase.in effort required to remove and dispose of such contamination. Translation of the 1 mrem / year or lower dose levels'into the radiological field. parameters used to guide decomissioning (e.g., microcuries per gram or disintegrations per minute per 100 square centimeters) would result in values for these parameters-i that would be difficult to detect and, thus,. difficult to utilize and verify in cleanup projects. This concern is exacerbated at sites with uranium,.
thorium, and radium contamination, where it may.not be feasible to attain' cleanup levels less than the 10 mres/ year criterion.- For perspective, EPA's ~
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. cleanup criterion for radium-226 in-contaminated soils at uranium mill i-l tailings sites corresponds to a level of risk that'is one hundred times larger than that associated with 10 mrem / year [ EPA 520/4-82-013-1].
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QUESTION 14.-(Continued)
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Mr. Stello informed the Commission of his reconmiendation to adopt the 10 mrem / year criterion-in a Comission paper dated September 9,1988 l
[$ECY88-257). Even if he had not recommended 10 mres/ year.it is reasonable l
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to believe that the Comission may have selected an individual dose criterion' of 10 mrem / year considering the feasibility of ~ demonstrating cleanup at lower
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levels and balancing the incremental reductions in health risk with the large' increase'in regulatory burden.
In fact, Mr. Stello provided the recoraendation specifically in response to a Comission request for " options for a Comission policy which establishes a generic number for exposures that-are below regulatory concern"- (see March 30, 1988, memorandum:from Samuel Chilk to Victor Stello). This Comission request also directed the staff to consider "de,,, facto" BRC levels that appear in current NRC regulations, which have already been protecting the public for-years.
l No practices would be more likely to be exempted using1the 10 mrem / year criterion rather than the 1 mres/ year criterion.
If the more restrictive level were established, it would just support lower release levels for exempted practices.- However, as. indicated above, the lower level may not be=
appropriate for-such activities as: decommissioning comercialinuclear.
facilities.
In addition, under the BRC policy,;the Comission could approve exemptions in excess of the individual dose criterion provided that the proponent of the practice demonstrates that (1) th' potential doses to e
4-individual members of the public are sufficiently small or:unlikely,
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OVESTION~14.(Continued)
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1 (2)furtherreductions'indosesareneither-significantintermsofprotecting the public health and safety and_ the environment nor readily achievable, and (3)thecollectivedosefromtheexemptedpractice'isaslowasreasonably J
achievable.
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i Finally, it is important to recognize that the final BRC policy does indeed -
adopt the 1 mrem / year criterion for-practices -involving widespread distribution, such as consumer products, j
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