NRC Generic Letter 81-07, Control of Heavy Loads

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February 3, 1981

TO ALL LICENSEES OF OPERATING PLANTS AND APPLICANTS FOR OPERATING LICENSES AND HOLDERS OF CONSTRUCTION PERMITS*

SUBJECT: CONTROL OF HEAVY LOADS (Generic Letter 81-07)

Gentleman:

By our leter dated December 22, 1980, you were requested to review your controls of the handling of heavy loads to determine the extent to which the guidelines of NUREG-0612 are presently satisfied at your facility and to identify the changes and modifications that would be required in order to fully satify these guidelines.

To expidite your review, three enclosures were included with the letter. One of the enclosures was Request for Additional Information on Control of Heavy Loads (Enclosure 3). We have found that five pages from Enclosure 3 were missing due to a reporduction error. The missing pages are enclosed with this letter. In addition the December 22, 1980, letter on Page 2 in Item 1 required that information identified in Section 2.1 through 2.4 of Enclosure 3 be included in a report documenting the results of your review. This requirement should be modified to read: "Sections 2.1 through 2.4 for PWR plants and Sections 2.1 through 2.3 for BWP plants."

Because of these errors we are extending the Enclosure 2 90-day implementation requirement to May 15, 1981.

Sincerely,

Darrell G. Eisenhut, Director Division of Licensing

Enclosure:

"Enclosure 3" missing pages

• With the exception of licensees for Indian Point 2 and 3, Zion 1 and 2 and Three Mile Island 1

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Attachment

(4) ANALYSIS OF PLANT STRUCTURES

The following information should be provided for analysses conducted to demonstrate compliance with Criteria III and IV of NUREG 0612, Section 5.1.

1. INITIAL CONDITIONS/ASSUMPTIONS

Discuss the assumptions used in the analysis, including:

a. Weight of heavy load

b. Impact area of load

c. Drop height

d. Drop location

e. Assumptions regarding credit taken in the analysis for the action ofimpact limiters

f. Thickness of walls or floor slabs impacted

g. Assumptions regarding drag forces caused by the environment

h. Load combinations considered

i. Material proporties of steel and concrete

2. METHOD OF ANALYSIS

Provide the mthod of analysis used to demonstrate that usfficient load-

carrying capability exists within the wall(s) or floor slab(s).

Identify any computer codes employed, and provide a description of their capabilities. If test data was employed, provide it and describe its applicability.

3. CONCLUSION

Provide an evaluation comparing the results of this analysis with Criteris III and IV of NUREG 0612, Section 5.1. Where safe-shutdown equipment has a ceiling or wall separating it from an overhead handling system, provide an evaluation to demonstrate that postualted load drops do not penetrate the ceiling or cause secondary missiles that could prevent a safe-shutdown system from perfoming its safety function.

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(3) A description of any Engineered Safety Feature filter system which includes information sufficient to demonstrate compliance with the guidelines of USNRC Regulatory Guide 1.52, "Design, Testing, and Maintenance Criteria for Engineered Safety Feature Atmosphere Cleanup System Air Filtration and Absorption Units of Light-Water-Cooled Nuclear Power Plants."

(4) A discussion of any intial conditions (e.g., manual values locked shut, containment airlocks or equipment hatches shut) necessary to ensure that releases will be terminated or mitigated upon Engineered Safety Feature actuation and the measure employed (i.e., Technical Specification and administractive controls) to ensure that these intial conditions are satisfied and that Engineered Safety Feature systems are operable prior to the load lift.

2. METHOD OF ANALYSIS

Discuss the method of analysis used to demonstrat that post-accident dose will be well within 10CFR100 limits. In presenting methodology used in determining the radiological consequences, the following imformation should be provided.

a. A description of the mathematical or physical model employed.

b. An identification and summary of any computer program used in this analysis.

c. The consideration of uncertainties in calculational methods, equpment performance, instrumentation response characteristics, or other indeterminate effects taken into account in the evaluation of the results.

3. CONCULSION

Provide an evaluation comparing the results of the analysis to Criterion I of NUREG 0162, Section 5.1. If the postulated heavy-load-drop accident analyzed bounds other postulated heavy-load drops, a list of these bounded heavy loads should be provided.

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bound other postulated heavy-load drops, alist of these bunded heavy loads should be provided.

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