NRC FORM 366

(04-02-2024)

U.S. NUCLEAR REGULATORY COMMISSION

LICENSEE EVENT REPORT (LER) 

(See Page 2 for required number of digits/characters for each block)

(See NUREG-1022, R.3 for instruction and guidance for completing this form 

http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 04/30/2027

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learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden 

estimate to the FOIA, Library, and Information Collections Branch (T-6 A10M), U. S. Nuclear Regulatory 

Commission, Washington, DC 20555-0001, or by email to Infocollects.Resource@nrc.gov, and the OMB reviewer 

at: OMB Office of Information and Regulatory Affairs, (3150-0104), Attn: Desk Officer for the Nuclear Regulatory 

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not required to respond to, a collection of information unless the document requesting or requiring the collection 

displays a currently valid OMB control number.

1. Facility Name

052

050 2. Docket Number 3. Page

1 OF

4. Title

5. Event Date

Month Day Year

6. LER Number

Year

-

Sequential 

Number

-

Revision 

No.

7. Report Date

Month Day Year

8. Other Facilities Involved

Facility Name

Facility Name

Docket Number

Docket Number

9. Operating Mode 10. Power Level

050

052

11. This Report is Submitted Pursuant to the Requirements of 10 CFR §: (Check all that apply)

10 CFR Part 20

20.2201(b)

20.2201(d)

20.2203(a)(1)

20.2203(a)(2)(i)

20.2203(a)(2)(ii)

20.2203(a)(2)(iii)

20.2203(a)(2)(iv)

20.2203(a)(2)(v)

20.2203(a)(2)(vi)

20.2203(a)(3)(i)

20.2203(a)(3)(ii)

20.2203(a)(4)

10 CFR Part 21

21.2(c)

10 CFR Part 50

50.36(c)(1)(i)(A)

50.36(c)(1)(ii)(A)

50.36(c)(2)

50.46(a)(3)(ii)

50.69(g)

50.73(a)(2)(i)(A)

50.73(a)(2)(i)(B)

50.73(a)(2)(i)(C)

50.73(a)(2)(ii)(A)

50.73(a)(2)(ii)(B)

50.73(a)(2)(iii)

50.73(a)(2)(iv)(A)

50.73(a)(2)(v)(A)

50.73(a)(2)(v)(B)

50.73(a)(2)(v)(C)

50.73(a)(2)(v)(D)

50.73(a)(2)(vii)

50.73(a)(2)(viii)(A)

50.73(a)(2)(viii)(B)

50.73(a)(2)(ix)(A)

50.73(a)(2)(x)

10 CFR Part 73

73.77(a)(1)

73.77(a)(2)(i)

73.77(a)(2)(ii)

73.1200(a)

73.1200(b)

73.1200(c)

73.1200(d)

73.1200(e)

73.1200(f)

73.1200(g)

73.1200(h)

OTHER (Specify here, in abstract, or NRC 366A).

12. Licensee Contact for this LER

Licensee Contact Phone Number (Include area code)

13. Complete One Line for each Component Failure Described in this Report

Cause System Component Manufacturer Reportable to IRIS Cause System Component Manufacturer Reportable to IRIS

14. Supplemental Report Expected

No Yes (If yes, complete 15. Expected Submission Date) 

15. Expected Submission Date

Month Day Year

16. Abstract (Limit to 1326 spaces, i.e., approximately 13 single-spaced typewritten lines)
REQUIRED NUMBER OF DIGITS/CHARACTERS FOR EACH BLOCK

BLOCK 

NUMBER

NUMBER OF 

DIGITS/CHARACTERS TITLE

1 UP TO 127 / 2 LINES FACILITY NAME

2

CHECK BOX FOR 050 OR 052 

10 TOTAL 

5 IN ADDITION TO 050 OR 052

DOCKET NUMBER

3 VARIES PAGE NUMBER

4 UP TO 230 / 2 LINES TITLE

5

8 TOTAL 

2 FOR MONTH 

2 FOR DAY 

4 FOR YEAR

EVENT DATE

6

9 TOTAL 

4 FOR YEAR 

3 FOR SEQUENTIAL NUMBER 

2 FOR REVISIONS NUMBER

LER NUMBER

7

8 TOTAL 

2 FOR MONTH 

2 FOR DAY 

4 FOR YEAR

REPORT DATE

8

UP TO 29 -- FACILITY NAME 

CHECK BOX FOR 050 OR 052 

10 TOTAL -- DOCKET NUMBER 

5 IN ADDITION TO 050 OR 052

OTHER FACILITIES INVOLVED

9 1 OPERATING MODE

10 3 POWER LEVEL

11 VARIES 

CHECK ALL BOXES THAT APPLY REQUIREMENTS OF 10 CFR

12 UP TO 90 FOR NAME 

10 FOR TELEPHONE LICENSEE CONTACT

13

CAUSE VARIES (UP TO 8) 

2 FOR SYSTEM (UP TO 8) 

4 FOR COMPONENT (UP TO 8) 

4 FOR MANUFACTURER (UP TO 8) 

IRIS VARIES (UP TO 10)

EACH COMPONENT FAILURE

14 1 

CHECK BOX THAT APPLIES SUPPLEMENTAL REPORT EXPECTED

15

8 TOTAL 

2 FOR MONTH 

2 FOR DAY 

4 FOR YEAR

EXPECTED SUBMISSION DATE

16 13 LINES OF TYPING ABSTRACT

LICENSEE EVENT REPORT (LER) (Continued) NRC FORM 366

(04-02-2024)