05000317/LER-2018-002, Items Non-Conforming to Design for Tornado Missile Protection
| ML18164A028 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 06/07/2018 |
| From: | Tierney T Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 2018-002-00 | |
| Download: ML18164A028 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability |
| 3172018002R00 - NRC Website | |
text
Exelon Generation June 7, 2018 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Calvert Cliffs Nuclear Power Plant, Units No. 1 and 2 Todd A. Tierney Plant Manager Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657 410 495 5205 Office 484-459-0142 Mobile www.exeloncorp.com todd.tierney@exeloncorp.com 10 CFR 50.73 Renewed Facility Operating License Nos. DPR-53 and DPR-69 NRC Docket Nos. 50-317 and 50-318
Subject:
Licensee Event Report 2018-002, Revision 00 Items Non-Conforming to Design for Tornado Missile Protection The attached report is being sent to you as required by 1 O CFR 50.73.
There are no regulatory commitments contained in this correspondence.
Should you have questions regarding this report, please contact Mr. Larry D. Smith at (410) 495-5219.
Respectfully, QC~
for Todd A. Tierney Plant Manager TAT/PSF/bjm
Attachment:
As stated cc:
NRC Project Manager, Calvert Cliffs NRC Regional Administrator, Region I NRC Resident Inspector, Calvert Cliffs S. Gray, MD-DNR
NRC FORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
, the NRC may not conduct or sponsor, and a person Jt,........
is not required to respond to, the information collection.
3.Page Calvert Cliffs Nuclear Power Plant, Unit 1 05000317 1
OF 4
- 4. Title Items Non-Conforming to Design for Tornado Missile Protection
- 5. Event Date
- 6. LEA Number
- 7. Report Date
- 8. Other Facilities Involved I
Sequential I Rev Facility Name Docket Number Month Day Year Year Number No.
Month Day Year Calvert Cliffs Nuclear Power Plant Unit 2 05000 318 Facility Name Docket Number 05 14 2018 2018 - 002 00 06 07 2018 05000
- 9. Operating Mode
- 11. This Report is Submitted Pursuant to the Requirements of 1 O CFR §: (Check all that apply)
D 20.2201(b)
D 20.2203(a)(3)(i)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
D 20.2201 (d)
D 20.2203(a)(3)(i1)
[8J 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B) 1 D 20.2203(a)(1)
() 20.2203(a)(4)
D so.73(a)(2)(iii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i)
D 50.36(c)(1)(i)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. Power Level D 20.2203(a)(2)(ii)
D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(v)(A)
D 73.71(a)(4)
D 20.2203(a)(2)(iii)
D so.36(c)(2)
D 50.73(a)(2)(v)(B)
D 73.71(a)(s)
D 20.2203(a)(2)(iv)
D so.46(a)(3)(ii)
D 50.73(a)(2)(v)(C)
D 73.77(a)(1) 100 D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A) l8J 50.73(a)(2)(v)(D)
D 73.77(a)(2)(i)
D 20.2203(a)(2)(vi) l8J 50.73(a)(2)(i)(B) l8J 50.73(a)(2)(vii)
D 73.77(a)(2)(ii)
D D Other (Specify in Abstract below or in D.
SAFETY ANALYSIS
There are no actual consequences resulting from this identified non-conforming condition. A tornado that could produce the design basis missile is highly unlikely in the mid-Atlantic region.
The probability of a design basis missile striking the Saltwater System subsystem piping in a fashion to render the SSC inoperable is also very low.
The FSAR described characteristics of the design basis tornado wind hazard and tornado generated missile hazard. These design requirements are stated as:
"Differential bursting pressure between the inside and outside of the containment structure is assumed to be 3 pounds per square inch positive pressure.
Lateral force is assumed as the force caused be a tornado funnel having a peripheral tangential velocity of 300 mph and a forward progression of 60 mph. The provisions for gust factors and variation of wind velocity with height do not apply.
A tornado driven missile equivalent to a 4000 pound automobile flying through the air at 50 mph and at not more than 25 feet above the ground or a 4 inch by 12 inch by 12 foot long piece of wood traveling end-on at 300 mph at any height."
NRG Enforcement Guidance Memorandum, EGM 15-002, Revision 1, provides for the application of NRG enforcement discretion which allows the identified non-conforming conditions on each Unit to be returned to an operable status based on the application of compensatory measures which are intended to reduce the likelihood that th*e tornado event would result in a failure of the Saltwater system subsystem on either Unit. Calvert Cliffs has applied the guidance in EGM 15-002, Revision 1 and NRG DSS-ISG-2016-01, Revision 1, Appendix A to determine the acceptable initial compensatory measures necessary to ensure that the identified non-conforming condition could be treated by the NRG with enforcement discretion.
E.
CORRECTIVE ACTIONS
Compensatory measures were implemented in accordance with NRG guidance contained in EGM 15-002 (revision 1) and DSS-ISG-2016-01 (revision 1) as described earlier. Enforcement discretion provided by EGM 15-002 remains in effect until June 10, 2020 for Calvert Cliffs, at which time modifications, analysis, license amendments, or other actions must be implemented to fully resolve the issue.
F.
PREVIOUS OCCURRENCES
No previous similar events have occurred at the site within the last 5 years.
00 G.
COMPONENT FAILURE DATA
No component failures were identified. Page_4_ of....1.....