In accordance with 5 CFR 1320, the information collection is approved for 3 years. Upon resubmission, the agency has committed to a rigorous reevaluation of their burden estimate, including reevaluating estimation through direct feedback from respondents. In particular, in relation to comments received, NRC has committed to evaluating the burden increase and any issues with duplication in information collection due to the requirement for embedded flaws violating the sizing criteria.
The NRC is proposing to amend its regulations in 10 CFR Part 50.61, to provide updated fracture toughness requirements for protection against pressurized thermal shock (PTS) events for pressurized water reactor (PWR) pressure vessels. These amended regulations will be captured in the mew 10 CFR 50.61a. The final rule would require new PTS requirements based on updated analysis methods. this action is being taken because the existing requirements are based on unnecessarily conservative probabilistic fracture mechanics analyses. This action would reduce a regulatory burden for licensees, specifically those licensees that expect to exceed the existing requirements before the expiration of their licenses. These new requirements would be voluntarily utilized by any PWR licensees as an alternative to complying with the existing requirements.
The requirements in 10 CFR 50.61a will only apply to those licensees that voluntarily choose compliance with this section as an alternative to compliance with the requirements specified in 10 CFR 50.61. Of the 69 currently operating PWR's, the staff projects that eight reactor vessels could exceed the screening criteria specified in 10 CFR 50.61 during their extended (60 year) lifetime. The NRC expects that each of these licensees will elect to apply the less stringent embrittlement correlations and screening criteria in 10 CFR 50. 61a rather than applying the compensatory measures of 10 CFR 50.61(b)(3) through (b)(7). Because it could take approximately up to 3 years to prepare the package for initial submittal to the NRC, the NRC estimates that only one licensee is expected to apply during the initial 3 year clearance period. The NRC assumes that, 3 years subsequent to the effective date of the final rule, one operating reactor licensee per year will choose to comply with 10 CFR 50.61a for the following eight years. Thus, in the three years following the effective date of this rule, one operating reactor would be affected by the RT max-x assessment and inservice testing and none would perform the flux reduction analyses nor the reactor vessel thermal annealing. Therefore, the estimated number of annual respondents is expected to be 0.333 per year and each respondent would provide two responses (i.e., one for the RT max-x assessment and one for the analysis of ASME Code inservice ultrasonic testing results).
On behalf of this Federal agency, I certify that the collection of information encompassed by this request complies with 5 CFR 1320.9 and the related provisions of 5 CFR 1320.8(b)(3).
The following is a summary of the topics, regarding the proposed collection of information, that the certification covers:
(i) Why the information is being collected;
(ii) Use of information;
(iii) Burden estimate;
(iv) Nature of response (voluntary, required for a benefit, or mandatory);
(v) Nature and extent of confidentiality; and
(vi) Need to display currently valid OMB control number;
If you are unable to certify compliance with any of these provisions, identify the item by leaving the box unchecked and explain the reason in the Supporting Statement.
10CFR50 PTS Final Rule SS 091709.doc
10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities