ML20294A145
| ML20294A145 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 03/07/2017 |
| From: | Stephanie Blaney NRC/OCIO/GEMSD/FLICB |
| To: | Hixson L Enformable |
| Shared Package | |
| ML20294A138 | List:
|
| References | |
| FOIA, NRC-2016-000731 | |
| Download: ML20294A145 (68) | |
Text
Dear FOIA Requester:
The FOIA Improvement Act of 2016, which was enacted on June 30, 2016, made several changes to the Freedom of Information Act (FOIA). Federal agencies must revise their FOIA regulations to reflect those changes by December 27, 2016. In addition to revising our regulations, we intend to update the Form 464, which we use to respond to FOIA requests.
In the interim, please see the comment box in Part I.C of the attached Form 464. The comment box includes information related to the recent changes to FOIA that is applicable to your FOIA request, including an updated time period for filing an administrative appeal with the NRC.
Sincerely yours, S~ B~ ISi Stephanie Blaney FOIA Officer
NRC FORM 464 Part I (12-2015)
REQUESTER:
!Lucas Hixson U.S. NUCLEAR REGULATORY COMMISSION RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) REQUEST DESCRIPTION OF REQUESTED RECORDS:
FOIA 1
2016-0731
RESPONSE
TYPE RESPONSE NUMBER II q
INTERIM FINAL DATE:
11 JIM o, 2011 Records corresponding to items 38 (ML16204A001), 51 (ML16236A0I8), and 57 (MLI6237A006) of your request, as further explained in the Comments Section, below.
0 0
0 PART I. - INFORMATION RELEASED Agency records subject to the request are already available in public ADAMS or on microfiche in the NRC Public Document Room.
Agency records subject to the request are enclosed.
Records subject to the request that contain information originated by or of interest to another Federal agency have been referred to that agency (see comments section) for a disclosure determination and direct response to you.
We are continuing to process your request.
See Comments.
AMOUNT*
PART I.A - FEES D You will be billed by NRC for the amount listed.
[{] None. Minimum fee threshold not met.
D Fees waived.
$11..!:=:=I=====.JI I D You will receive a refund for the amount listed.
- see Comments for details 0
0 PART 1.8 -INFORMATION NOT LOCATED OR WITHHELD FROM DISCLOSURE We did not locate any agency records responsive to your request. Note: Agencies may treat three discrete categories of law enforcement and national security records as not subject to the FOIA ("exclusions"). 5 U.S.C. 552(c). This is a standard notification given to all requesters; it should not be taken to mean that any excluded records do, or do not, exist.
We have withheld certain information pursuant to the FOIA exemptions described, and for the reasons stated, in Part II.
Because this is an interim response to your request, you may not appeal at this time. We will notify you of your right to appeal any of the responses we have issued in response to your request when we issue our final determination.
You may appeal this final determination within 30 calendar days of the date of this response by sending a letter or email to the FOIA Officer, at U.S. Nuclear Regulatory Commission, Washington, D.C. 20555-0001, or FOIA.Resoun;:e@nrc.gov.
Please be sure to include on your letter or email that it is a "FOIA Appeal."
PART I.C COMMENTS ( Use attached Comments continuation page if required)
In conformance with the FOIA Improvement Act of 2016, the NRC is informing you that you have the right to seek assistance from the NRC's FOIA Public Liaison.
This interim response addresses three more of the records enumerated in your request. Since the date of your request, MLI6204A001, ML16236A018, and MLI6237A006 have been removed from ADAMS. However, because the NRC was able to locate them by the accession numbers when your request was received, we have processed the records,
[ continued on next page]
SIGNATURE - FREEDOM OF INFORMATI Stephanie..'A.. 'Bfaney NRC Form 464 Part I (12-2015)
Page 2 of 3
NRC FORM 464 Part I U.S. NUCLEAR REGULATORY COMMISSION (12-2015)
REQUESTER:
jLucas Hixson RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) REQUEST Continued PART I.C COMMENTS (Continued) except as noted below.
FOIA 1
2016-0731
RESPONSE
TYPE RESPONSE NUMBER I I g
INTERIM FINAL DATE:
11 MAR O 7 :tf111 I
MLl 6204A00 I was determined to be a personal, rather than agency, record. It is an email, dated September 14, 2012, that you sent to various congressional staff members. Although two items are shown to have been attached to that email, neither was included in ML16204A001. Since NRC has not located another copy of the email received in the course of any NRC staff member's assigned duties in any of its records systems, we have determined that the email is a personal record. As such, it is not subject to the FOIA and has not been processed.
ML16236A018 is an email exchange between staff members in the Offices of Nuclear Regulatory Research (RES) and New Reactors (NRO), to which a red-lined draft of a "Style Sheet", including personal advice and recommendations about writing style by its author, was attached. This draft was not finalized, although it is similar to NUREG-1379 NRC Editorial Style Guide. It is also noted that the focus of the email exchange was a particular template NRO used to write reviews of post-Fukushima Recommendation 2. 1 Flood Hazard Reevaluation Reports, which is different altogether from the red-lined draft the originating RES staff member had attached to his email. A copy of the email exchange is enclosed.
ML16237A006 is a letter from a third party individual (who has provided a privacy waiver) to then-EDO Bill Borchardt and then-ChiefFOIA Officer Darren Ash, following up on a pending FOIA appeal, FOIA-2013-009A, including seven enclosures. The enclosures consist of: ( 1) an acknowledgment letter; (2) a Form 464 response package to 2013-0126 (which is already publicly available as ML13106A167), including an appendix listing the already publicly available redacted records responsive to the request; (3) ML13099A247 (as redacted); (4) ML13039A084 (as redacted); (5)
ML13039A0086 (as redacted); (5) a copy of the U.S. Army Corps of Engineers (ACE)'s Engineer Manual, "General Design and Construction Considerations for Earth and Rock-Fill Dams," (which is publicly available at ACE's website) and a Continuing Education & Development, Inc. cover sheet for a program on this subject; (which is also publicly available at its website); and (7) an unredacted copy of the cross-section diagram of the Jocassee Dam. With the exception of enclosure 7, the pages of this record are enclosed. As for enclosure 7, this diagram has already been addressed in interim response 5 (relating to the slides in items 25, 55, and 58), wherein it was redacted on the basis of exemption 7F.
NRC Form 464 Part I (12-2015)
Page 3 of 3
NRC FORM 464 Part II U.S. NUCLEAR REGULATORY COMMISSION FOIA (12-2015)
RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) REQUEST 1
2016-073 l#q DATE:
I I 1111.0 n 7 '11117 PART II.A -- APPLICABLE EXEMPTIONS Records subject to the request are being withheld in their entirety or in part under the FOIA exemption(s) as indicated below (5 U.S.C. 552(b)).
D Exemption 1: The withheld information is properly classified pursuant to an Executive Order protecting national security information.
D Exemption 2: The withheld information relates solely to the internal personnel rules and practices of NRC.
D Exemption 3: The withheld information is specifically exempted from public disclosure by the statute indicated.
D Sections 141-145 of the Atomic Energy Act. which prohibits the disclosure of Restricted Data or Formerly Restricted Data (42 U.S.C. 2161-2165).
D Section 147 of the Atomic Energy Act, which prohibits the disclosure of Unclassified Safeguards Information (42 U.S.C. 2167).
41 U.S.C. 4702(b), which prohibits the disclosure of contractor proposals, except when incorporated into the contract between the agency and the submitter of the proposal.
Exemption 4: The withheld information is a trade secret or confidential commercial or financial information that is being withheld for the reason(s) indicated.
The information is considered to be proprietary because it concerns a licensee's or applicant's physical protection or material control and accounting program for special nuclear material pursuant to 10 CFR 2.390(d)(1).
The information is considered to be another type or confidential business (proprietary) information.
The information was submitted by a foreign source and received in confidence pursuant to 10 CFR 2.390(d)(2).
[{] Exemption 5: The withheld information consists of interagency or intraagency records that are normally privileged in civil litigation.
[{] Deliberative process privilege.
D Attorney work product privilege.
D Attorney-client privilege.
Exemption 6: The withheld information from a personnel, medical, or similar file, is exempted from public disclosure because its disclosure would result in a dearly unwarranted invasion of personal privacy.
[{] Exemption 7: The withheld information consists of records compiled for law enforcement purposes and is being withheld for the reason(s) indicated.
D (A) Disclosure could reasonably be expected to interfere with an open enforcement proceeding.
D (C) Disclosure could reasonably be expected to constitute an unwarranted invasion of personal privacy.
(D) The information consists of names and other information the disclosure of which could reasonably be expected to reveal identities of confidential sources.
(E) Disclosure would reveal techniques and procedures for law enforcement investigations or prosecutions, or guidelines that could reasonably be expected to risk circumvention of the law.
[{] (Fl Disclosure could reasonably be expected to endanger the life or physical safety of an individual.
D Other I I
PART 11.B -- DENYING OFFICIALS In accordance with 10 CFR 9.25(g) and 9.25(h) of the U.S. Nuclear Regulatory Commission regulations, the official(s) listed below have made the determination to withhold certain information responsive to your request DENYING OFFICIAL TITLE/OFFICE RECORDS DENIED APP£LlA TE OFFICIAL EDO SECY I
Stephanie A. Blaney I I FOIA Officer 11 draft and security-sensitive information I 0 I
I 11 I
I 11 I
I Appeals must be made in writing within 30 calendar days of the date of this response by sending a letter or email to the FOIA Officer, at U.S. Nuclear Regulatory Commission, Washington, O.C. 20555-0001, or FOIA.Resource@nrc.gov. Please be sure to include on your letter or email that it is a "FOIA Appeal."
NRC Form 464 Part II (12-2015)
Page 1 of 1 I
Criscione, Lawrence From:
Sent:
To:
Cc:
Subject:
Attachments:
- Larry, Cook, Christopher Monday, August 22, 2016 7:35 AM Criscione, Lawrence; Salley, MarkHenry; Peters, Sean Rivera-Varona, Aida; Harvey, Brad; Correia, Richard RE: response: Style Sheet for JLD Flooding Review Documents R2.l_SA_ Template_FINAL_ML13218A150.pdf The 66-page red lined draft is withheld in full under exS.
The file you attached is a draft job aid that Mark McBride created (he called it a Style Sheet), but he did not finish it before he retired. No one has worked on the job aid since he retired.
Our staff assessment template is ML13218A150 (attached) and was completed in September 2013. Please note that the template is a non-public document in ADAMS.
Since 2014, we have issued approximately 22 staff assessments. Over the years, our staff assessments have evolved as a result of Commission direction and as we have tried to improve our products. For example, all staff assessments issued in 2016 were written after issuance of an Interim Staff Letter (ISR) to the licensee (for example, here's Salem Generating Station's ISR Letter: ML15244B266). In 2013 and when the template was finished, the concept of an ISR did not exist. Therefore, if you compare our most recent staff assessment to the template, you will see that our staff assessments generally follow the 2013 template. However, we also evolved as the process changed in response to Commission direction plus we're always trying to improve.
In summary, the best guidance I can provide is a reference to our most recent staff assessments plus the attached 2013 template.
- Regards, Chris From: Criscione, Lawrence Sent: Friday, August 19, 2016 12:56 PM To: Cook, Christopher <Christopher.Cook@nrc.gov>; Salley, MarkHenry <MarkHenry.Salley@nrc.gov>; Peters, Sean
<Sean.Peters@nrc.gov>
Cc: Rivera-Varona, Aida <Aida.Rivera-Varona@nrc.gov>; Harvey, Brad <Brad.Harvey@nrc.gov>; Correia, Richard
<Richard.Correia@nrc.gov>
Subject:
RE: response: Style Sheet for JILD Flooding Review Documents
- Chris, I got the document from an NRO colleague who received it from Mark McBride in 2015.
I'm reviewing the Chairman's response to the Office of Special Counsel's referral regarding my disclosure on the NRC's handling of flooding hazards.
The flooding reviews are being conducted as "staff assessments" vice as "safety evaluations". Safety evaluations are handled under LI C-101. I'm trying to determine what the guidance is for "staff assessments".
The purpose of my questions to you are two-fold:
- 1. To find out if the attached document is the only guidance there is for conducting staff assessments and, if there is other guidance, to find out where it is at so I can review it.
- 2. To find a clean copy of the attached document so that I can reference it in my comments on the Chairman's response to the Office of Special Counsel.
So, that being said:
Do you know of any guidance your staff uses when conducting their staff assessments of the flooding reviews (other than the attached document)?
Do you know if the attached version is in ADAMS and-if not-can you tell me who the current document owner is and where I can find the latest version of the document?
- Thanks, Larry 573-230-3959 From: Cook, Christopher Sent: Friday, August 19, 2016 12:32 PM To: Criscione, Lawrence <Lawrence.Criscione@nrc.gov>; Salley, MarkHenry <MarkHenry.Salley@nrc.gov>; Peters, Sean
<Sean.Peters@nrc.gov>
Cc: Rivera-Varona, Aida <Aida.Rivera-Varona@nrc.gov>; Harvey, Brad <Brad.Harvey@nrc.gov>
Subject:
response: Style Sheet for JLD Flooding Review Documents
- Larry, Where did you find this document? I think it was produced as a job aid for my branch and it lives out on the JLD SharePt site, but I'm not sure. Can you also let me know the purpose for your question?
I'm also trying to understand the nexus between your 3 questions, our other ORA activities (primarily in DRA/FXHAB), and what you're trying to accomplish.
I've included Mark Salley and Sean Peters in case they prefer to respond instead.
- Thanks, Chris Christopher B. Cook, Ph.D., P.E.
Chief, Hydrology and Meteorology Branch 1 US NRC, Office of New Reactors (301) 415-6397 Christopher.Cook@nrc.gov From: Criscione, Lawrence Sent: Friday, August 19, 201611:47 AM To: Cook, Christopher <Christopher.Cook@nrc.gov>
Cc: Rivera-Varona, Aida <Aida.Rivera-Varona@nrc.gov>; Harvey, Brad <Brad.Harvey@nrc.gov>
Subject:
RE: Style Sheet for JLD Flooding Review Documents
- Chris, I was told Aida is out sick today and it looks like she is on vacation next week. Mark McBride has apparently retired.
I am attempting to find the guidance used by the NRC staff to conduct the "Staff Assessments" of the flooding reviews. I just spoke with Brad HaNey and he doesn't think we have any such guidance-other than the out-of-date style guide attached to this email.
Do you know of any guidance that your staff uses when conducting their staff assessments of the flooding reviews? Do you know if the attached document is in ADAMS? If not, can you tell me who the current document owner is and where I can find the latest version of the document?
Thank you, Larry Lawrence S. Criscione 573-230-3959 From: Criscione, Lawrence Sent: Friday, August 19, 201611:18 AM To: Rivera-Varona, Aida <Aida.Rivera-Varona@nrc.gov>
Subject:
Style Sheet for JLD Flooding Review Documents
- Aida, The person listed as the owner of the attached document (Mark McBride) no longer works for the NRC but he was in your branch. Do you know where the attached document is located? Is it in ADAMS? Is it possible for me to get the most current revision (i.e. one without unaccepted changes)?
I am trying to find guidance on conducting Staff Assessments. Other than this document, where is the guidance for conducting a Staff Assessment?
- Thanks, Larry Lawrence S. Criscione Reliability & Risk Engineer RES/ DRA/HFRB Tl0-844 (573) 230-3959
1412 Dial Court Springfield, IL 62704 Bill Borchardt, Executive Director for Operations (EDO)
Darren Ash, Chief Freedom of Information Act Officer United States Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Update to FOIA Appeal 2013-009A
Dear Mr. Borchardt and Mr. Ash:
April 11, 2013 This letter is an update to a FOIA appeal the NRC acknowledged on March 29, 2013 concerning FOIA/PA 2013-0126. The NRC's acknowledgment letter to that appeal is included as Enclosure 1. Today (2013-04-11), I received a response to FOIA 2013-0126, which I have included as Enclosure 2. Note that this response has come 40 working days after my initial request and 9 working days after I submitted an appeal in accordance with 10 CFR §9.25.
On Tuesday, February 12, 2013 I requested five records from tile NRC:
- 1. ML103490330, Oconee Nuclear Site, Units 1, 2, and 3. Oconee Response to Confirmatory Action Letter (CAL) 2-10-003, dated Nov. 29, 2010
- 2.
ML111460063, Oconee Nuclear Site, Units 1, 2, and 3. Response to Confirmatory Action Letter (CAL) 2-10-003, dated April 29, 2011
- 3.
ML100780084, Generic Failure Rate Evaluation for Jocassee Dam Risk Analysis
- 4.
ML101610083, Oconee Nuclear Station, Units 1, 2, and 3, - External Flood Commitments
- 5.
ML101900305, Identification of a Generic External Flooding Issue Due to Potential Dam Failures My incoming FOIA request can be found in ADAMS as ML13044A487.
Today, I was provided the following documents in your response to FOIA 2013-0126:
- 1. ML103490330 (released without redactions so not part of FOIA Appeal 2013-009A)
- 2.
ML13099A247 instead of M L111460063 (included with this appeal as Enclosure 3)
- 3.
ML13039A084 instead of ML100780084 (included with this appeal as Enclosure 4)
- 4. ML101610083 (released without redactions so can be removed from FOIA Appeal 2013-009A)
- 5.
ML13039A086 instead of ML101900305 (included with this appeal as Enclosure 5)
For the records denied, Exemption 7F of the Freedom of Information Act is claimed. I disagree with this decision and in this letter am providing you the reasons for that disagreement so that, if you chose, you can take this information into account when evaluating FOIA Appeal 2013-009A.
I see nothing in the records requested which indicate they were compiled for law enforcement purposes nor do I see anything which would indicate to me that disclosure could reasonably be expected to endanger the life or physical safety of an individual. It appears to me that the NRC is using Exemption 7F as a means to withhold information which it believes may be beneficial to terrorists or saboteurs yet none of the information withheld pertains to security processes or hardware. The information withheld
merely pertains to the nuclear safety hazards which deficiencies in the Oconee Station's flooding defenses pose to the American public. These safety risks are present due to the risks of natural disasters and latent engineering/construction flaws and have nothing specifically pertaining to terrorist activities.
As a specific example, consider ML100780084, the Generic Failure Rate Evaluation of Jocassee Dam Risk Analysis, submitted by James Vail, Fernando Ferrante, and Jeff Mitman on March 15, 2010. This document was a formal write up of analyses done by NRR in 2007 /2008 to support Region !l's efforts to get Duke Energy to address safety concerns regarding flooding protection at Oconee. In this document, the Reliability & Risk Analysts at NRR estimated the failure frequency of the Lake Jocassee Dam to be 2.8E-4/yr which equates to a 1 in 3600 chance of failing in any given year. Given that the catastrophic failure of the Lake Jocassee Dam would likely lead to a meltdown of the three reactors at the Oconee Nuclear Station, the dam failure rate calculated by Vail, Ferrante & Mitman suggests that the probability of a nuclear accident at Oconee Nuclear Station is ten times what it is at a typical US reactor plant. This is the type of important information which President Obama expects us to share with the American public (see the President's 2009-01-19 memo on Open Government). Yet the NRC did not share this information with the public. Instead, we stamped the Vail et. al. analysis as "Official Use Only-Security-Related Information" and for years never publicly mentioned its existence. Then, in response to a FOIA request by Dave Lochbaum, we released a redacted version of this supposed "Security-Related" report as ML13039A084. The only redaction in this 15 page report was a figure on page 1 showing the generic construction of Jocassee Dam - a figure very similar to what one can find in any Civil Engineering text book. I have included similar publicly available figures as Enclosure 6. Despite the fact that this figure did not provide any insight to terrorists, it apparently kept this important report from the public for nearly three years. On March 25, 2013 I attended a public meeting with Duke Energy in which this very same figure was presented by [)uke Energy as a slide (see Enclosure 7). The slide show from this meeting was forwarded to me by Jim Riccio of Greenpeace and was posted by the NRC on their public website (ML13084A022). So this supposedly "Security-Related" figure, which caused NRR to keep the Vail et. al. analysis from the public for nearly three years and which NRR had redact from Dave Lochbaum's FOIA response in February 2013, was by March 2013 being emailed by NRR to Greenpeace and being posted by NRR on the world-wide web.
The world-wide web gets that name for a reason: it is truly world-wide. Iran, North Korea, Pakistan, Saudi Arabia, and the host of other countries which sponsor terrorist activity against the United States have access to this world-wide web. So why can NRR email this generic drawing to Greenpeace and post it on the web for our enemies to see yet must redact it from the version of the Vail et. al. analysis that it sent to David Lochbaum, Tom Zeller and Paul Blanch in response to their separate FOIA requests? Is this figure "Security-Related" or not? If it is, why are we sharing it on the world-wide web? If it is not, why did we keep the Vail et. al. report from the public for nearly three years and why do we still refuse to release it in its entirety? These are rhetorical questions. Please do not delay answering FOIA Appeal 2013-009A due to these questions. I merely wish to point out to you some inconsistencies in your control of information in the event you would like to consider those inconsistencies while addressing FOIA Appeal 2013-009A.
Additionally, information redacted from the documents supplied to me today has already been publicly release to Greenpeace in our 2013-02-06 partial response (ML130520858) to FOIA 2012-0325 (ML12263A087).
Under FOIA Appeal 2013-009A, please release the following three records to me with no redactions.
ML111460063, Oconee Nuclear Site, Units 1, 2, and 3. Response to Confirmatory Action Letter (CAL) 2-10-003, dated April 29, 2011 ML100780084, Generic Failure Rate Evaluation for Jocassee Dam Risk Analysis ML101900305, Identification of a Generic External Flooding Issue Due to Potential Dam Failures Again, this letter is an update to FOIA Appeal 2013-009A in response to documents I received today from the NRC. The information I received came in response to FOIA Request 2013-0126 and not FOIA Appeal 20013-009A. I expect FOIA Appeal 2013-009A to be answered within 30 working days from March 29, 2013 (i.e. by May 10, 2013). I am providing the information in this letter for you to consider if you so choose.
Although I live in Springfield, IL, I work in Rockville, MD. Please do not send documents to my home in Springfield, IL as I will not get them in a timely manner. Please send all written correspondence to me via email at LSCriscione@hotmail.com. If your processes will not allow you to do this, then please contact me via phone or email and I will come by the FOIA desk to pick up the correspondence.
Very respectfully, d,..,.,,,_ s Ct.*
Lawrence S. Criscione, PE (573) 230-3959 Enclosures (7)
Cc:
Billie Garde, Esq., Clifford & Garde Louis Clark, The Government Accountability Project Fernando Ferrante, NRC/NRR/DRA Jeff Mitman, NRC/NRR/DRA Dave Lochbaum, Union of Concerned Scientists Jim Riccio, Greenpeace Tom Zeller, Huffington Post Paul Blanch, consultant
Lawrence Criscione 1412 Dial Court Springfield, IL 62704
Dear Requester:
of Update to FOIA 2013f09A UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555- 0001 March 29, 2013 FOIA/PA-2013-00009A FOIA/PA-2013-00126 FOIA/PA-2013-0001 0A FOIA/PA-2013-00127 FOIA/PA-2013-00011 A FOIA/PA-2013-00128 We have logged your March 29, 2013 correspondences as appeals for Lack of Response to you under FOIA/PA-2013-00126, FOIA/PA-2013-00127 and FOIA/PA-2013-00128.
Your appeals have been assigned the following reference numbers that you should use in any future communications with us about your appeals: FOIA/PA-2013-00009A, FOIA/PA-2013-0001 0A, and FOIA/PA-2013-00011 A.
The following person is the FOIA/PA Specialist who has been assigned responsibility for your appeals: Linda Kilgore at 301-415-5775.
If you have questions on any matters concerning your FOIA/PA appeals, please feel free to contact the FOIA/PA Specialist assigned to your appeals or me. I can be reached at 301 -415-7169.
Enclosure:
Incoming Request Sincerely, ISi Donna L. Sealing FOIA/Privacy Act Officer Office of Information Services of Update to FOIA 2013-009A U.S. NUCLEAR REGULATORY COMMISSION FOIA/PA RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) / PRIVACY ACT(PA)REQUEST 2013-0126
RESPONSE
TYPE RESPONSE NUMBER
[Zj FINAL PARTIAL REQUESTER Lawrence Criscione OATE APft 11 2013 PART I. - INFORMATION RELEASED D No additional agency records subject to the request have been located.
D Requested records are available through another public distribution program. See Comments section I
Agency records subject to the request that are Identified in the listed appendices are already available for pubhc inspection and copying at the NRC Public Document Room.
- ====,
I APPENO!ccs I Agency records subject to the request that are Identified in the listed appendices are being made available for
. public inspection and copying at the NRC Public Document Room.
Enclosed is Information on how you may obtain access to and the charges for copying records located at the NRC Public Document Room, 11555 Rockville Pike, Rockville, MO 20852-2738.
I APPENOICES I
____......, Agency records subject to the request are enclosed.
Records subject to the request that contain information originated by or of interest to another Federal agency have been referred to that agency (see comments section) for a disclosure determination and direct response to you.
We are continuing to process your request.
See Comments.
AMOUNT*
PART I.A -- FEES D You will be billed by NRC for the amount listed.
D You will receive a refund for the amount listed.
[Z] None. Minimum fee threshold not met D Fees waived.
s I I
- See ccmments for details 0
0 PART I.B - INFORMATION NOT LOCATED OR WITHHELD FROM DISCLOSURE No agency records subject to the request have been located. For your information, Congress excluded three discrete categories of law enforcement and national security records from the requirements of the FOIA. See 5 U.S.C. § 552(c)
(2006 & Supp. IV (2010). This response Is limited to those records that are subject to the requirements of the FOIA. This Is a standard notification that is given to all our requesters and should not be taken as an indication that excruded records do, or do no~ exist.
Certain Information in the requested records is being withheld from disclosure pursuant to the exemptions described In and for the reasons stated in Part 11.
This determination may be appealed within 30 days by writing to the FOIA/PA Officer, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. Clear1y state on the envelope and In the letter that It is a "FOIA/PA Appeal."
PART I.C COMMENTS ( Use attached Comments continuation page If required)
The incoming FOIA request will be available in ADAMS at MLI 3044A487.
SIGN U ~ ~AN~lp~A!=T OFFICER D nrn I.;. Sealing
- ~-j NRC FORM 464 Part 1 (10-2012) of Update to FOIA 2013-009A NRC FORM 464 Part II (4-2011)
U.S. NUCLEAR REGULATORY COMMISSION FOIA/PA DATE RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) / PRIVACY ACT (PA) REQUEST 2013-0126 APft 1 1 2013 l~PPENOICES PART II.A** APPLICABLE EXEMPTIONS I
Records subject to the request tha1 are described In the enclosed Appendices are being wl1hheld in their entirely or In part under the
. Exemption No.(s) ol 1he PA and/or the FOIA as Indicated below (5 U.S.C. 552a and/or 5 U.S.C. 552(b)).
Exemption 1: The withheld informaUon Is properly classified pursuan1 to Executive Order 12958.
Exemption 2: The withheld lnlorma1lon relates solely to the internal personnel rules and practices of NRC.
Exemption 3: The withheld information is specifically exempted from public disclosure by statute indicated.
Sections 141-145 of the Atomic Energy Act, which prohibits the disclosure of Restricted Data or Former1y Restricted Data (42 U.S.C.
2161-2165).
Section 147 of the Atomic Energy Act. which prohibits the disclosure of Unclassified Safeguards Information (42 U.S.C. 2167).
41 U.S.C.* Section 253b, subsection (m)(1 ), prohibits the dis closure of contractor proposals In the possession and control of an executive agency to any person under section 552 ol TIiie 5, U.S.C. (the FOIA). except when incorporated into the contract between the agency and the submitter of the proposal D
Exemption 4: The wlthheld information Is a trade secret or commercial or financial Information that Is being withheld for the reason(s) Indicated.
D The information is considered to be confidential business (proprietary) information.
The Information Is considered to be proprietary because It concerns a licensee's or applicanrs physical protection or material control and accounting program for special nuclear material pursuant to 10 CFR 2.390(d)(1).
D The Information was submitted by a foreign source and received In confidence pursuant to 10 CFR 2.390(d)(2).
D Disclosure will harm an identifiable private or governmental interest.
Exemption 5: The withheld Information consists of interagency or intraagency records that are not available through discovery during lltlgatlon.
Applicable privileges:
Deliberative process: Disclosure of predecisional Information would tend to inhibit the open and frank exchange of ideas essential lo the deliberative process. 1/vhere records are withheld in their entirety, the facts are inextricably intertwined with the predecisional Information.
There also are no reasonably segregable faeluaf portions because the release of the facts would permit an indirect inquiry into the predecisional process of the agency.
D Attorney work-product privilege. (Documents prepared by an attorney in contemplation of litigation)
D Attorney-client privilege. (Confidential communications between an attorney and his/her client)
Exemption 6: The withheld information Is exempted from public dlselosure because Its disclosure would result in a clearly unwarranted invasion of personal privacy, f7l Exemption 7: The withheld Information consists of records compiled for law enforcement purposes and is being wtthheld for the reason(s) l.!..J indicated.
(A) Disclosure could reasonably be expected to Interfere with an enforcement proceeding (e.g.* It would reveal the scope, direction. and focus of enforcement efforts, and thus could possibly allow recipients to take action to shield potential wrong doing or a violation of NRC requirements from investigators).
(C) Disclosure could constitute an unwarranted Invasion of personal privacy.
(D) The information consists of names of Individuals and other Information the disclosure of which could reasonably be expected to reveal ldentaies of oonfidenlial sources.
D (E) Disclosure would reveal techniques and procedures for law enforcement investigations or prosecutions. or guidelines that could reasonably be expected to risk circumvention of the law.
[Z] (F) Disclosure could reasonably be expected lo endanger the life or physical safety of an individual.
OTHER (Specify)
I PART 11,B ** DENYING OFFICIALS Pursuant to 10 CFR 9.25(g), 9.25(h), and/or 9.65(b) of the U.S. Nuclear Regulatory Commission regulations, It has been determined that the information withheld is exempt from production or disclosure, and !Fiat its production or disclosure is contrary to the public interest. The person responsible for the denial are those officials identified below as denying officials and the FOIA/PA Officer for any denials that may be appealed to the Executive Director for Operations (EDO).
DENYING OFFICIAL TITLE/OFFICE RECORDS DENIED APPELLATE OFFICIAL 1-----------,-------------------+------------+~E_DO-'-il SECY.L!2..._
Victor McCrcc
)Regional Administrator, Region II Sec Appendices A2 IZ] IO 0 Eric J Leeds
!office Director, NRR Sec Appendix A3, AS 0
D D I
DI Appeal must be made in writing within 30 days of receipt of this response. Appeals should be mailed to the FOIA/Privacy Act Officer, U.S. Nuclear Regulatory Commission, Wa*shington, DC 20555-0001, for action by the appropriate appellate officlal(s). You should clearfy state on the envelope and letter that it is a "FOIAIPA Appeal."
NRC FORM 464 Part II (4-2011) of Update to FOIA 2013-009A Re: FOIA-2013-0126 APPENDIX A RECORDS ALREADY AVAILABLE IN THE PDR NO.
ACCESSION NO.
DATE DESCRIPTION/CPAGE COUNT)
- 1.
ML103490330 11/29/10 Oconee Nuclear Site, Units 1, 2 and 3, Oconee Response to Confirmatory Action Letter 2-10-003 (7 Pages) 2 ML13099A247 04/29/11 Oconee Nuclear Site, Units 1, 2, 3, Response to Confirmatory Action Letter (CAL) 2-10-003 (16 pages) Exemption 7F
- 3.
ML13039A084 03/15/10 Generic Failure Rate Evaluation for Jocassee Dam (15 pages) Exemption 7F
- 4.
ML101610083 06/03/10 Oconee Nuclear Station - External Flood Commitments (5 pages)
- 5.
ML13039A086 07 /19/10 Memorandum to Benjamin Beasley, RES from Lois James, NRR,
Subject:
Identification of a Generic External Flooding Issue Due to Potential Dam Failures (9 pages) Exemption 7F of Update to FOIA 2013-009A
' ~Duke
,&Energy,...
April 29, 2011 Mr. Victor McCrea, Regional Administrator U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, Georgia 30303-1257
Subject:
Duke Energy Carolinas, LLC Oconee Nuclear Site, Units 1, 2, and 3 T. PRESTON GILLESPIE, JR.
Vice President Oconee Nuclear Station Duke Energy ONO J VP I 7800 Rochester Hwy.
Seneca, SC 29672 864-873-4478 864-873-4208 fa~
T. Glllesp/e@duke-energy.com Renewed Facility Operating License, DPR-38, DPR-47, and DPR-55 Docket Numbers 50-269, 50-270, and 50-287 Oconee Response to Confirmatory Action Letter (CAL) 2-10-003
References:
- 1. Nuclear Regulatory Commission (NRC) letter from Luis A. Reyes to Dave Baxter (Duke Energy), "Confirmatory Action Letter - Oconee Nuclear Station, Units 1, 2, and 3 Commitments to Address External Flooding Concerns (TAC Nos. ME3065, ME3066, and ME3067)" dated June 22, 2010
- 2. Nuclear Regulatory Commission (NRC) letter from Eric Leeds to Preston Gillespie (Duke Energy), "Staff Assessment of Duke's Response to Confirmatory Action Letter Regarding Duke's Commitments to Address E~ernal Flooding Concerns at the Oconee Nuclear Station, Units 1, 2, and 3 (ONS) (TAC Nos. ME3065, ME3066, and ME3067)"
dated January 28, 2011
- 3. Duke Energy letter from T. Preston Gillespie to Luis Reyes (Nuclear Regulatory Commission), "Oconee Response to Confirmatory Action Letter (CAL) 2-10-003" dated November 29, 201 O
- 4. Duke Energy letter from Dave Baxter to U.S. Nuclear Regulatory Commission, "Oconee External Flood Interim Actions" dated January 15, 201 o The purpose of this letter is to respond to the NRC's request, as noted in the Confirmatory Action Letter dated June 22, 201 O (Reference 1 ), for a list of all modifications necessary to adequately protect the Oconee site from the impact of a postulated failure of the Jocassee Dam.
www. duke-ener8f. com
Victor Mccree Nuclear Regulatory Commission April 29, 2011 Page 2 of Update to FOIA 2013-009A Duke Energy agreed to provide this list and the associated implementation dates by April 30, 2011 (Reference 3).
In Reference 2, the NRC found that the documentation previously supplied by Duke Energy provided sufficient justification that the parameters and analysis used to evaluate the inundation of the Oconee Nuclear Station (ONS) site, resulting from the postulated failure of the Jocassee Dam, were bounded. The Information provided by Duke Energy was in response to one of the NRC's requests in Reference 1. is a proposed strategy for mitigating the external flood impacts from a postulated failure of the Jocassee Dam. Calculations supporting this strategy are in progress and have not been finalized. Attachment 2 is a description of proposed site modifications necessary to implement the mitigation strategy. During design and implementation of these modifications, the actions required by Reference 1 will remain in place. Also, periodic independent assessments and emergency response organization drills of the interim actions will be conducted to verify continued viability.
Design of the modifications is in progress and details may change as the process continues.
The capability to provide adequate protection of the Oconee units and the spent fuel from a postulated failure of the Jocassee dam will be documented within the Updated Final Safety Analysis Report (UFSAR).
Duke Energy will submit the design of the Intake Dike Diversion Wall and the Intake Dike Tie Section modification (discussed in Attachment 2) to the Federal Energy Regulatory Commission (FERC). Duke Energy will also submit any License Amendment Requests (LARs) to the NRC that are necessitated by the power block flood wall modification. The modifications identified in will be completed within a time frame of thirty (30) months plus FERC and NRC LAR review and approval time.
Duke Energy is committed to an orderly and thorough approach to resolution of the external flood mitigation issues at ONS so that the dates provided above and completion of the related modifications can be achieved. Duke Energy is proceeding, consistent with Its corporate governance requirements, to obtain necessary internal approvals to fund the Implementation of these commitments. Additionally, Duke Energy must undergo additional land acquisitions for relocation of the 100 kV (Fant) line towers.
Since this letter contains security sensitive information, Duke Energy hereby requests the NRC withhold the letter and its attachments from public disclosure pursuant to 10 CFR 2.390(d)(1),
"Public Inspections, exemptions, requests for withholding.*
If you have questions concerning this matter, please contact Bob Meixell, Oconee Regulatory Compliance, at 864-873-3279.
Victor Mccree Nuclear Regulatory Commission Aprll 29, 2011 Page3 of Update to FOIA 2013-009A I declare under penalty of perjury that the foregoing is true and correct. Executed on April 29, 2011.
Sincerely, rr~,,c.ca 4plC T. Preston Gillesple, Jr.
Vice President Oconee Nuclear Station Attachments: - Jocassee Dam Failure Flood Mitigation Strategy - Description of Modifications
Victor Mccree Nuclear Regulatory Commission April 29, 2011 Page4 cc:
Mr. Joseph G. Giitter, Director Division of Operating Reactor Licensing U. S. Nuclear Regulatory Commission Mail Stop 0-8 E1A Washington, D. C. 20555 Mr. John Stang, Project Manager Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop 0-8 G9A Washington, D. C. 20555 Mr. Andy Sabisch Senior Resident Inspector Oconee Nuclear Site Susan E. Jenkins, Manager Radioactive & Infectious Waste Management Division of Waste Management SC Dept. of Health and Environmental Control 2600 Bull Street Columbia, SC 29201 of Update to FOIA 2013-009A d)(1) of Update to FOIA 2013-009A ATTACHMENT 1 JOCASSEE DAM FAILURE FLOOD MITIGATION STRATEGY
Withhold from Publlc Olsclosu Nuclear Regulatory Commission of Update to FOIA 2013-009A - Jocassee Dam Failure Flood Mitigation Strategy Page 2 Jocassee Dam Failure Flood Mitigation Strategy The strategy proposed within this attachment will continue to ensure adequate protection of the Oconee units and spent fuel in the unlikely occurrence of a Jocassee Dam failure. This strategy is provided based on the following Initial Oconee site conditions:
All three units are at power operation Unit 1 &2 and Unit 3 Spent Fuel Pools (SFP) heat rates are consistent with that associated with all three units at power operation (no full core offload)
Condenser Circulating Water (CCW) is not dewatered The Standby Shutdown Facility (SSF) is available
- I (b )(7)(F)
Credited Systems, Structures, and Components are in normal alignments When the Oconee site is not within these initial conditions or associated mitigation systems are unavailable, appropriate compensatory measures will be taken based on the insight provided through the 10 CFR 50.65(a)(4) program, as applicable.
Furthermore, the mitigation strategy assumes the following:
The Jocassee Dam failure does not occur concunrent with design basis accidents, design events, or transients.
The Jocassee Dam failure does not occur concurrent with an earthquake.
The occurrence of a single failure, as well as the failure of a control rod to fully insert, is not assumed.
Systems, Structures, and Components (SSCs) to mitigate a Jocassee Dam failure are not required to be QA~1.
UFSAR Section 2.4.2.2 documents the Flood Design Considerations for both the Keowee and Jocassee Reservoirs. The dams and other hydraulic structures were designed with adequate freeboard and structural safety factors to safely accommodate the effects of Probable Maximum Precipitation (PMP). UFSAR Section 2.4.4 documents that Jocassee has been designed to the same seismic input conditions as Oconee Nuclear Station (ONS). Flooding due to the potential failure of the Jocassee Dam or Keowee Dam was not addressed and was considered to be beyond design basis. Thus, the current ONS licensing basis defines protection from external flooding caused by a Probable Maximum Flood (PMF) applicable to ONS which was analyzed based on the PMP. This basis satisfied General Design Criterion 2 of the UFSAR (Section 3.1.2).
Criterion 2 of the UFSAR Imposes design criteria on select (designated as Essential) SSCs associated with the forces and conditions associated with natural phenomena. As such, natural phenomena events are not design basis events at Oconee, instead they impose design criteria of Update to FOIA 2013-009A Wrthho,"""1.\\1!!lJ"'VII Nuclear Regulatory Commission - Jocassee Dam Failure Flood Mitigation Strategy Page 3 on SSCs identified for mitigation of accidents. As was the original site design for flooding conditions, these design criteria are to remain within the constraints of the PMF applicable to ONS which was analyzed based on the PMP. Therefore, the original PMF analysis will remain as the flood design criteria for the Essential SSCs.
A Jocassee Dam failure can subject the Oconee Nuclear Site to adverse conditions beyond the plant design basis. Specifically, the postulated failure of the Jocassee Dam could result In a loss of off-site and emergency power, loss of external water sources and Inundation of a majority of the station's SSCs. As described and accepted within Reference 1, compensatory measures are in place to mitigate these potential adverse consequences. Modifications are planned and discussed In Attachment 2 to improve the capability to maintain the three Oconee units as well as both SFPs in a condition that adequately protects the fuel. Upon completion of these modifications and implementation of the mitigation strategy within station procedures and processes, the compensatory measures described within Reference 1 will no longer be required.
Flood barriers will be designed to protect the credited SS'),l,lil.-l!,. ~'"-"-"w....>LLI,\\ Turbine Building, Auxiliary Building and the SSF, and the surrounding ard (b)(7)(F) followin the power source for p ant sys1ems.
protected power source would also allow the SSF to be owered without startin the SSF diesel enerator thus (b)(7)(F)
(b)(7)(F)
'---------:=----:--::------:-:-:-----.,.,..----:--:------------=-----__,..-.11 Thus, mitigation of the Jocassee Dam failure would be limited by the loss of external water sources to ONS. The water inventory trapped in the CCW system piping system would be the credited source of water for core decay heat removal and SFP makeup.
The planned modifications have been assumed to be implemented in the mitigation strategy for establishing and maintaining the three Oconee units as well as both SFPs in a condition that adequately protects the fuel. The mitigation strategy for this scenario has been subdlvid'ed into the following phases:
Phase 1: Reactor shutdown and establishment of Mode 3 Phase 2: Initiation of Natural Circulation Cooldown of the Reactor Coolant System (RCS) to 250°F Phase 3: Maintain RCS at S250°F of Update to FOIA 2013-009A
- n.
Withhold from Pu-....._,--""--
vn.....w_..-......,w.1* (d){1)
Nuclear Regulatory Commission - Jocassee Dam Failure Flood Mitigation Strategy Page4 Phase 1: Reactor shutdown and establishment of Mode 3 (b)(7)(F)
.__ ________________ __,! Actions are taken to establish the flood protective features, such as Isolating Turbine Building and yard drain flowpaths and closing flood barrier access openings.
L-------~- Following notification, the ONS Switchyards are assumed to remain a v a ii ab I e to each unit's startup transformer which provides power to normal and emergency systems.
The operators will take actions to shutdown the reactor(s) and establish Mode 3 with T _ and RCS pressure at approximately 525°F and 2155 psig respectively, using normal plant systems.
Operator actions will be undertaken to begin boration of the RCS for cold shutdown conditions.
Normal secondary plant systems will remain in operation during this phase.
The operators will take actions to disable the Essential Siphon Vacuum System and vent it to prevent reverse siphon flow from the CCW inlet piping back to the Intake Canal when it is lost.
The emergency CCW discharge flow path will be disabled by operators to prevent any loss of CCW. Actions will be taken to isolate the High Pressure Service Water {HPSW) outside of the flood protected area to ensure its capability to provide cooling water to the High Pressure Injection (HPI) pump motors.
Phase 2: Initiation of Natural Circulation Cooldown of the Reactor Coolant System to 250°F (b)(7)(F) results In a momentary loss of power to ea are lost due to the loss of ower to the sta (b)(7)(F)
.__ _______________________,... The SSF is normally powered from Unit 2's MFB, but it is load shed. Operator action wlll be taken to restore power to the SSF from Unit 2's MFB. Following reset of the load shed, power for the SSF would be provided from Unit 2's MFB to minimize any usage of the CCW inventory for SSF diesel operation.
The rising flood water in the ONS Intake Canal is postulated to result in failure of the Lake Keowee impoundment including the Intake canal. This requires the shutdown of the Low Pressure Servie:e Water (LPSW) pumps to conserve water inventory in the CCW piping.
of Update to FOIA 2013-009A etter Wlthhold from Public Dlsdosure Nuclear Regulatory Commission -Jocassee Dam Failure Flood Mitigation Strategy Page 5 Heat removal from the Spent Fuel Cooling system is normally provided by the Recirculated Cooling Water (RCW) system. Following the overtopplng of the Keowee Dam, the loss of CCW flow results in a loss of RCW cooling. This leaves the Units 1 & 2 shared SFP and the Unit 3 SFP without cooling. The SFP will eventually heat up to the point of boiling. When boiling occurs, the SFP level will decrease. Makeup to the SFP would be initiated from available sources including the water contained within the CCW buried piping to maintal n a sufficient water level above the spent fuel stored in the pools.
The shutdown of the LPSW pumps results in a loss of cooling to such items as the Reactor Building, HPI pumps, the Component Cooling System, the motor-driven EFW pumps, and the Low Pressure Injection coo'lers.
With the shutdown of the CCW and LPSW systems, environmental conditions within the plant would be established as needed by the use of temporary equipment and operation of necessary existing and temporary ventilation systems. The temporary equipment will be powered from a 4160VAC electrical bus tha1 receives power from CT5.
The HP1 pumps can continue to operate because backup cooling is provided from the HPSW system via the Elevated Water Storage Tank (EWST}. Power to an HPSW pump would be restored and the pump would be operated to replenish the EWST to maintain cooling water to the HPI pump motor coolers. The HPI system operates to maintain pressurizer level at the desired setpoint.
A loss of normal secondary systems is experienced due to the temporary loss of power to the main feeder buses. Decay heat removal would initially be maintained by the EFW System. The motor-driven EFW pumps must be secured due to the loss of LPSW cooling. The turbine-driven EFW pump does not require LPSW for cooling and is therefore allowed to continue to operate to feed the SGs. The loss of condenser cooling will result in the SGs being steamed to atmosphere using the Atmospheric Dump Valves which results in depletion of the condensate Inventory.
Upon a loss of normal RCS letdown capability a cooldown is initiated. Since RCPs cannot be operated based on a loss of cooling and power to the pumps, a natural circulation cooldown must be performed. Oepressurization of the RCS would be accomplished by means of the Power Operated Relief Valve and/or auxiliary spray.
Core decay heat removal would eventually be transferred to the SSF Auxiliary Service Water (ASW) system to utilize the trapped water inventory in the CCW piping. With the use of tlhe SSF ASW system, valve alignments would be made to maximize the available trapped water inventory in the CCW piping to the SSF ASW pump suction. This would be accomplished by cross-connecting the CCW inlet and discharge piping between all three units.
of Update to FOIA 2013-009A This letter conntlll:Ml&Curily nsll In nnation Withhold from Public Disclosure un 1 OCFR.3 d)(1)
Nuclear Regulatory Commission - Jocassee Dam Failure Flood Mitigation Strategy Page6 When the cooldown has been completed, the operating HPI pump would be stopped. The SSF ASW system would continue to supply the steam generators (SGs) to maintain decay heat removal.
Phase 3: Maintain RCS at S250°F Core decay heat removal will be maintained by natural circulation of the RCS with the SSF ASW system providing decay heat removal by means of SG feeding and steaming through the ADVs.
The HPI system will be operated as needed to maintain RCS water level within an acceptable band. Pressurizer heaters will be operated as necessary to maintain RCS pressure. Water level In the SFP will be maintained at a sufficient level above the spent fuel stored in the pools.
The suction source for the SSF ASW system and the SFP makeup system is the water inventory trapped In the CCW piping.
of Update to FOIA 2013-009A ATTACHMENT 2.
DESCRIPTION OF MODIFICATIONS of Update to FOIA 2013-009A Wi old """"'..,,.,.,
Nuclear Regulatory Commission - Description of Modifications Page 2 Based on the mitigation strategy discussed within Attachment 1, the following table Identifies proposed modifications to mitigate site flooding following the postulated failure of the Jocassee Dam.
Specifically, modifications will be required to protect the required SSCs to meet the mitigation strategy and provide a dedicated flood protected power supply following a postulated Jocassee Dam failure. Protection of the credited SSCs including the Turbine Building, Auxiliary Building, SSF, and the surrounding yard (including CT5 Substation) will be accomplished with flood barriers and associated infr st (b)(7)(F)
No Category Description 1
(b)(7)(F)
(b)(7)(F)
~
1A (b)(7)(F)
~
1B CT5 Substation Modify CTS Substation to supply the standby bus and a new recovery eauipment bus.
2 Protect Required Protect required SSCa and the surrounding yard due SSCs and the to Keowee lmpoundment failures and rising waters In Surrounding Yard the tallrace area 2A Power Block Flood Wall Install a new flood wall located on the east side of the Oconee site.
28 Intake Dike Diversion Install a new diversion wall along the northern side of the Wall ON$ intake dike 2C Turbine Building Drain Install barriers to minimize flood waters from entering Into Isolation the Turbine Building from rising waters in the tailrace area 2D Yard Drain Isolation Install barriers to minimize flood waters from entering the site 3
SFP Makeup Utilizes stored water Inventory for makeup to the SFP 3A SSF Service Water SSF ASW minimum flow line diverted to outside SSF for Discharge Flow Path transfer to SFP 3B SFP Level Install new SFP level Instrumentation rated for post-flood Instrumentation conditions of Update to FOIA 2013-009A tter co
- s security se In Withhold from Public o_,.,,ouu...,,,,iler 10CF Nuclear Regulatory Commission - Description of Modifications Page3 Description of Modifications:
1-Dedlcated, Flood Protected Power In order to ensure an adequate dedicated power path to the Oconee site after a Jocassee Dam failure, the following modifications are required:
(b)(7)(F) 1 B - CT5 Substation (b)(7)(F) r-,::~~~~l I The Jocassee Dam L------------------------'
failure requires modification of the CT5 Substation to add multiple power paths for mitigation. The Initial function of the CT5 Substation will be to provide emergency power to loads required to mitigate the Jocassee Dam failure from the Oconee Standby Buses.
Isolation for CT5 to the Standby Bus power path will be provided by a new breaker in the CT5 Substation. A secondary function of the CT5 Substation will be to provide an additional power path to temporary loads used for mitigation. These loads will be powered by a new recovery equipment bus designed for the CTS Substation. This bus wlll provide power to portable distribution tra1ilers at voltage levels of 4160V, 600V, 480V, 208V, and 120V for these temporary loads. Isolation/protection of this bus will be provided by a new breaker.
Individual loads wlll be isolated/protected by load-specific fusible gang switches on the load side of this bus.
General Design Parameters:
Loading of CT5 transformer does not exceed the 12/16/20MVA rating consistent with UFSAR Section 8.2.1.4.
2-Protect Required SSCa and the Surrounding Yard In order to prevent flood waters from flowing Into the site from the Keowee impoundment failure and from rising waters In the tallrace area, the following modifications are required:
Nuclear Regulatory Commission - Description of Modifications Page4 2A - Power Block Flood Wall of Update to FOIA 2013-009A (1)
The new Power Block flood Wall will envelope the eastern side and the southern end of the ONS protected area. The wall is comprised of 3 sections: The Discharge Diversion Section, The East Wall, and the Intake Dike Tie Section. The wall will have at least one vehicular access and one personnel access located at the north road crossing, each of which will have flood protection capability.
General Design Parameters:
Classification: Class 3, consistent with UFSAR Section 3.2.1.1.3 Design Loadings:
Dead + Wind (UFSAR Section 3.3.2.4) or Dead + Hydrodynamic (Flood) (Reference 2)
Additional Design Considerations: General erosion; flood scour; debris; leakage from access gates, expansion joints, and unidentified locations (details to be determined); site drainage; and soil exploration and characterization. Interactions of non-seismic SSCs with seismic SSCs will be addressed.
Discharge Diversion Section (approximately 300 ft long)
Wall Height: Top Elev.1.-l(b_l(_7_l(F_) _________ _.
Protection Height Margin: Approximately 2 ft.
Wall Thickness: Material dependent Design Codes: Similar to UFSAR Section 3.8.5.4.3 Design Methodology: UFSAR Section 3.8.5.4.3 East wall Section (approximately 2000 ft. long)
Wall Height: Top Etev. lL-(b_l(_7
)_(F_) ----------~
Protection Height Margin: Approximately 2 ft.
Wall Thickness: Material dependent Design Codes: Similar to UFSAR Section 3.8.5.4.3 Design Methodology: UFSAR Section 3.8.5.4.3 Access Barriers: Vehicular access closure is planned to be a gate (sliding or hinged, possibly designed with some mechanical sealing devices), or stop logs (concrete or steel),
similar to standard flood gates or other similar barriers.
Withho*.....,_.,,=......,61 Nuclear Regulatory Commission - Description of Modifications Pages Intake Dike Tie Section (approximately 160 ft. long) of Update to FOIA 2013-009A Wall Height: Top Elev.1l(b)(7l(F)
~apering to zero height Protection Height Margin: Approximately 2 ft.
Wall Thickness: Material dependent. Wall ls planned to be a combination of Power Block.
Wall transitioning to an embankment (compacted fill) wall tied to the existing Intake Canal Dike embankment.
Design Codes: Similar to UFSAR Section 3.8.5.4.3 Design Methodology: UFSAR Section 3.8.5.4.3 28 - Intake Dike Diversion Wall This wall will prevent the rising waters on Lake Keowee, more specifically the Oconee Intake Canal, from flowing over the northern crest of the dike and directly into the yard. The wall will be located on the northern side of the dike crest, going from the northeast comer of the dike to the northwest comer of the dike where it will tie to higher ground. One access gate is planned for the exist~ng roadway connecting the western portion of the nuclear site to the crest of the dike. Design parameters for the Intake Dike Diversion Wall are described below:
General Design Parameters Classification: Class 3, consistent with UFSAR Section 3.2.1.1.3 Design Loadings:
Dead + Wind (UFSAR Section 3.3.2.4) or Dead + Hydrodynamic (Flood) (Reference 2)
Additional Design Considerations: General erosion; flood scour, debris; leakage from access gates, expansion joints, and unidentified locations (details to be detennined); and soil exploration and characterization. Interactions of non-seismic SSCs with seismic SSCs will be addressed.
Wall Height: Top Elev.l{bl(7l(F)
Protection Height MargL.i-n:_,A... p-p-ro_x..,.im_a....,.te_,l,-
y"""2..,.ft,.... _____ _ _..
Wall Thickness: Material dependent Design Codes: Similar to UFSAR Section 3.8.5.4.3 Design Methodology: UFSAR Section 3.8.5.4.3 Access Barriers: Vehicular access closure Is planned to be a gate or stop logs similar to standard flood gates or other similar barriers.
of Update to FOIA 2013-009A This tette11,1:9~1S-S411Catify'le*
W h Id
- 1)
Nuclear Regulatory Comm sion - Description of Modifications Page6 2C - Turbine Building Drain Isolation The free-flowing capability of the Turbine Building drain will be restricted during the site external flood by a flood gate or other similar barrier to minimize water flowing into the Turbine Building from the flooded tallrace area. Design parameters are described below:
Classification: Class 3, consistent with UFSAR Section 3.2.1.1.3 Design Loadings: Dead + Hydrodynamic (Flood) (Reference 2)
Design Code: Sluice gate or valve, standard to be determined 2D - Yard Drain Isolation This modification adds. a flood gate or other similar barrier to minimize the amount of water entering the flood protected area via the yard drains. Design parameters are described below:
Classification: Class 3, consistent with UFSAR Section 3.2.1.1. 3 Design Loadings: Dead + Hydrodynamic (Flood) (Reference 2)
Design Code: Sluice gate or valve, standard to be determined 3-SFP Makeup In order to provide makeup to the Spent Fuel Pools after a Jocassee Dam failure, the following modifications are required:
3A - SSF Service Water Discharge Flow Path The capability to remove water from the CCW pipe by means of the SSF ASW Minimum Flow Line will be added for collection and transfer to the Units 1 & 2 shared SFP and the Unit 3 SFP.
38 - SFP Level !nstrumentatlon SFP level instrumentation will be designed to monitor the SFP level to ensure proper level ls maintained during SFP boiling conditions.
of FOIA Appeal 2013-009A Update Letter
~U.S.NRC UNITED STATES NUCLEAR. I\\EGm.ATORY COMMISSION Protecting People and the Environment Generic Failure Rate Evaluation for Jocassee Dam March 15, 2010 Probabilistic Risk Assessment {PRA) Analyst:
James Vail, Reliability and Risk Analyst, NRR/DRA/APOB Probabilistic Risk As~essment (PRA) Analyst:
Probabilistic Risk Assessment (PRA) Analyst:
Peer Reviewer:
Fernando Ferranle, Reliability and Risk Analyst, NRR/ORA/APOB Jeff Mitman, Senior Reliability and Risk Analyst, NRR/DRAIAPOB Steven A. Laur, Senior Technical Advisor NRR/DRA of FOIA Appeal 2013-009A Update Letter GENERIC FAILURE RATE EVALUATION FOR JOCASSEE DAM BY DIVISION OF RISK ASSESSMENT'S PRA OPERATIONAL SUPPORT BRANCH The following documents a generic dam failure rate analysis applicable to the Jocassee Dam performed by the PRA Operational Support Branch (APOB) of the Division of Risk Assessment (DRA) in the Office of Nuclear Reactor Regulation {NRR). The analysis, technical justifications, and databases used in support of the calculations for the derived value are briefly discussed.
Portions of this evaluation were initially performed in 2007 but not formally documented at that time.
Approach The approach used in deriving a generic failure rate value applicable to the Jocassee Dam included: (I) an evaluation of the physical characteristics and description o1 the dam, (ii) an assessment of the overall U.S. dam population for those with similar features to the Jocassee Dam, (iii) a study of U.S. dam perfonnance information for failure events that may be applicable to this subset of the overall population, and (iv) a calculation of a point estimate, as well as consideration of the uncertainty involved, for the failure rate given the observed failure events and the observed time period (in dam-years),
Jocassee Dam Description The Jocassee Dam is located In northwest South Carolina, forming a reservoir (Lake Jocassee) with a 7565-acre surface area, a water volume of 1,160,298 acre-feet, and a total drainage area of 147 sq-miles at full pond (1,110 feet elevation above mean sea level). The reservoir was created in 1973 with the construction of the dam. The Jocassee Dam is an embankment dam with an earthen core and rockfilled and random rockfilled zones (see Figure 1 ).
(b)(7)(F)
...§fNSITl1/Efl'qPORMATION-OFFICIAL O~Y 1
of FOIA Appeal 2013-009A Update Letter The dam is 385 feet in height (1,125 crest elevation above mean sea level) and 1,825 feet in length and, along with two homogeneous earthfill dikes and a reinforced concrete spillway, is part of a hydroelectric station and pumped storage project. The underground powerhouse generating units receive water from two cylindrical intake towers through eight openings. The water is channeled from the intake towers to four hydro turbines by two bifurcated power tunnels which are constructed through the bedrock of the east abutment. Two gates 33 feet in height and 38 feet in width control the outflow of the spillway.
Databases The staff used two databases to obtain information about the population of dams in the US: the National Inventory of Dams (NID}, maintained by the US Army Corps of Engineers, and the National Performance of Dams Program (NPDP), developed by the Department of CMI and Environmental Engineering at Stanford University. The NIO database-contains data describing multiple attributes such as dimensions, type, impoundment characteristics, etc. The NPDP database contains a collection of dam incident reports searchable by various parameters including dam type, incident type, and consequences.
Failure Events Table 1 lists the applicable dam failures initially derived from the NPOP database. To choose these 13 failures, the analysts used criteria based on the previously discussed dam characteristics (i.e., dam type and height). However, due to the ambiguity in the classificatfon of.
the dam type (i.e., based on material composition) between and within the NIO and NPDP databases, as well as the lack of information to establish an exact link with the Jocassee Dam characteristics for every data point, the staff considered both rockfill dams and mixed-rockfill dams (i.e., those classified exclusively as rockfill dams as well as mixed dam types that include rockfill in their categorization). It should be noted that the NPDP database does not list any failures post-2006 and at least two well-known large dam failures in the U.S. are not included:
the Big Bay Dam in Mississippi (March 2004) and the Taum Sauk Rese,voir (December 2005) in Missouri. While the Big Bay Dam was an earthen dam (i.e., excluded based on dam type).
the Taum Sauk Reservoir consisted of a concrete-faced rockfill dam approximately 100 feet in height and was, therefore, included in the current analysis.
Additionally, the list was screened to take into consideration (i) failure events observed between 1900 and 2005, and (ii) failure events observed between 1940 and 2005; under the assumption that events prior to these construction periods could produce different results representative of distinct design practices. In part, this choice was due to the lack of information on the exact construction date of several dams in the database. The staff expended an extensive effort to determine th~ construction completion date for several dams for which the information was missing in the NPOP database (this information is included in Table 1 ).
Several failures listed in Table 1 have (or are assumed to have) occurred within a few years of either the start or completion of construction (e.g., the Lower Hell Hole Dam and the Frenchman Dam failures). Based op the information available and the estimated completion dates, the staff screened out such failures since the occurrence of the events was assumed to be related to the construction phase and, therefore, not applicable to a mature dam such as Jocassee.
Finally, the analysts chose to include the Dresser No. 4 Dam failure, because they deemed this dam to be similar to the Jocassee Dam in composition (i.e., a large mixed earthJill-rockfill dam),
SFI\\IS!JIUE 11413'0~MPiTION OFFICIAL USE ot*LY..
2 of FOIA Appeal 2013-009A Update Letter despite the fact that it is listed as a tailings dam (i.e., a dam theoretically built under lower standards of quality and maintenanc~)-
Therefore, the final list of failures of dams similar to, and therefore applicable to, the Jocassee Dam includes 6 failures occurring between 1900 and 2005. These six failures are highlighted in Table 1. The staff included these failures based on the following criteria: (i) rockfill or mixed-rockfill dam type, (ii) dam height above 50 feet. (iii) failure occurring after 1900, and (iv} no failures during or within a few years of completion of construction. Note that if failures occurring prior to-1940 are screened, then only 4 events remain: (1) Taum Sauk, (2) Dresser No.4 Dam, (3) Skagway, *and (4) Kem Brothers Reservoir. It should be noted that there are 1 to 3 failures of dams bullt between 1940 and 2005 depending on whether the entries with unknown construction dates are excluded or not, respectively (in similar fashion, there are 3 to 5 failures for dams constructed between 1900*2005 excluding or not entries with unknown construction dates, respectively).
Total Dam-years Calculation
. To calculate the dam failure rate, the staff needed to obtain the total number of dam.years of both failed and non-failed dams. The analysts extracted a subset of dams from the NID database based on a set of parameters to narrow the US population of dams to those reflecting the characteristics of the Jocassee Dam discussed above, i.e., large rockfill dams. They assumed that dams above 50 feet in height appropriately reflect design practices and structural characteristics of larger dams such as Jocassee. This height criterion was consistent with the large dam definition (WCD, 2000) established by the International Commission on Large Dams (ICOLD) which ~defines a large dam as a dam with a height of 15m or more from the foundation." If dams are between 5*15 meters high and have a reservoir volume of more than 3 million cubic meters, ICOLD also classified such dams as large. Hence, the staff used this definition as a screening criterion. The dams considered for calculation of the total dam-years were those in the NID database that were categorized exclusively as 'Rocl<fill' dams (i.e., those listed under the 'ER' abbreviation, intended to correspond to rockfill dams for NID cataloguing purposes).
The staff included the dam-year contributions from SkagwaY-and the replacement for the failed Frenchman Dam, while those from Kern Brothers Reservoir, Dresser No. 4 Dam, Penn Forest, and the failed Frenchman Dam were not included. This was because the staff judges that including the dam-year contribution from these specific dams would not significantly impacl the resulting dam-year total. The staff calculated the final result using the difference between the last year in the available data (2005) and either 1900 or 1940. For the 1900-2005 period, the staff" obtained a total of 21,490 dam-years; while for 1940-.2005 the result was 13,889.dam~
years. See Appendix A for a tabulation of the dams and the associated dam-years.
3 of FOIA Appeal 2013-009A Update Letter.
SENSlllVE INFORM;t(fl61* OFFIGIAt-USE.QNl.¥ Tbl11'fll'tfd f'I a e : m1a IS 0 am a1 ure even app11ca e o e ocassee am ts l'bltthJ D
Dam Name Incident Completion Year Year(Esl)
Taum Sauk 2005 1963 Dresser No.4 Dam 1975 Unknown Skagway 1965 1925 Hell Hole 1964 1964 Penn Forest 1960 1gsc Frenchman *
- 1952 1951 Da:11 Ker.: Brothers 1949 Unknown Reservoir lake Francis 1899
- 1sgg Lafayette
!928 1928 Manitou 1924 1917 Lyman 1915 1912 Lower Olay 1916 1897 Blad\\ Rock 1909 1908 i~rtType Dam Type Heignl OesCllptlon From NPDP Dl!tabase (Except Taum Sau~);;'
.(ft}..
j-Overtopping Rockfill 94 Dvertopped due to over-pumping of niservoir. !ndependent ana~is indicated sewral root causes (e.g., lad of mon~oring, spillway).
EarthRockfill Piping
/Tailings 105 Catastrophic failure thai created a breach 300 feet 'Mde in the lellee.
Inflow Food
- Rockfill 79 The dam lai~d curing a ftood in 1965.
Hyijrologic Event Nol Known Rockfill 410 Dam failed du'ing construction. Overtopped by 100 leet -washing out most or tlie fill.
Piping Concrete Earth 151 Partial failJre. Sin'<hole occurred in ups1ream slope of dam.
Rockf*II Inflow Flood
- Rocknll 63 Runoff from r,etti'lg snow, A dike section was overtoppad early Hydrologic Event morning April 15, 1952. Later lhat day, dam breached.
Selllement Earth Roddill 54 Failure due to excessive settlement of fill.
Blowou1 fa:.ure under concrete spillway weir struclure during period Piping Earth -~0Ckfill 79 of heavy spil~ay How. Spillway failure thought lo be due to piping in soft saturated fcundation.
Emoankment Slide Earth Rockfill 132 Foundat~n slide during oonstruction (at 120 feet). Height raised to 170 feet in 1932. Not sure if this is ronsidered a failure.
Seepage Earth Rodmll.
123 Partial fa~ure Wc!S disintegrating and c:onve~ed into gra~el fill.
Failure by µiiing through abutment;* undermined by passage of water Piping Earth Rockfill 76.4 under cap of lava rock which Hanked dam and exlended beneath spillway. Man pM of dam uninjured.
Spillway Earth Rod(fill 154 Foundation $;ide during rons1ruclion {al 120 feet). Height raised to 170 fool in 1932. Not sure if !his is oonsldered a failure.
Failure by piping through abutment; undermined by passage ol waler Piping Earth Rockfill 70 under cap of,aw ~ck which Hanked dam and exlended beneath spillway. PortKl" of spillway dropped 7 feel; some fill at soulh end washed ou:. Mair, part of dam uninjured.
SQl!Sl+II" IHF9RMMION -OfFlel:~L USE Ol'ftV 4
of FOIA Appeal 2013-009A Update Letter SENSITIVE INmRMATl~Fr lCIAL U5E ONLY Generic Point Estimate of the Dam Failure Rate The staff calculated the point estimate by dividing the number of applicable dam failures (see Table 1 above) by the total applicable dam-years (derived as described previously). Assuming a 1900-2005 range for the year of occurrence of the failure events and the dam-year estimation (based on completion year), the analysts obtained a failure rate of 2.BE-4 per dam-year. When considering a 1940-2005 rainge, the staff obtained a result of 2.9E-4 per dam-year.
Because the.NID database does not give Information regarding the quality of design, construction and/or maintenance, and the NPDP database does not consistently supply information on the dam health (i.e., is It well maintained?) at time of failure, the staff could not derive failure rates for above or below average built and maintained dams. This lack of information precluded the staff from making any judgment as to whether Jocassee is or is not an above average designed, constructed and maintained dam deserving of a failure frequency different than an average failure frequency.
Additionally, the staff recognizes that ambiguity and lack of complete information with respect to dam type, construction completion data, and darn incident reporting, may result In variations in the failure rate estimation. Therefore, the staff performed a simple sensitivity study in order to evaluate the changes due to screening failure events and cut-off year criteria. The results are shown in Table 2 for an assumed number of failures and clearly indicated that the results exhibit small variations for the period cut-off selected ( 1900-2005 and 1940-2005) and the number of failures considered (6 and 4, respectively). Additionally, the extent of the variation in the point estimate is shown for other number of failures and cut-off years based on the subset of darns selected. The table illustrates that the order-of-magnitude failure frequency estimate does not change significantly if the number of failures is increased or decreased slightly.
Table 2: Failure Rate Sensitivity Analysis ASSUMED NUMBER OF FAILURES CUT-DAM-OFF YEARS
- DAMS 2
3 4
5 6
7 ALL 25137 484 4.0E-05 8.0E-05 1.2E-04 1.6E*04 2.0E-04 2.4E-04 2.8E-04 1900 21490 466 4.7E-05 9.3E-05 1.4E-04 1.9E-04 2.3E-04 2.8E-04 3.3E-04 1910 19778 449 5.1E-05 1.0E-04 1.SE-04 2.0E-04 2.SE-04 3.0E-04 3.SE-04 1920 18389 434 5.4E-05 1.1 E-04 1.6E-04 2.2E-04 2.7E-04 3.3E-04 3.8E-04 1930 16475 410 6.1E-05 1.2E-04 1.8E-04 2.4E-04 3.0E-04 4.2E-04 1940 13889 373 7.2E-05 1.4E-04 2.2E-04 2.9E-04 5.0E-04 1950 12269 346 8.2E-0S 1.6E-04 2.4E-04 3.3E-04 5.7E-04 1960 8453 270 1.2E-04 2.4E-04 3.SE-04 4.7E-04 8.3E-04 1970 3242 143 1980 1339 82 1990 381 36 FAILURE RATE GIVEN# NUMBER OF FAILURES AND CUTOFF YEAR 5
of FOIA Appeal 2013-009A Update Letter Bayesian Estimate of the Dam Failure Rate To evaluate the dam failure rate uncertainty, the staff conducted a Bayesian analysis of the failure rate for the 1900-2005 period via a Bayesian analysis approach (Atwood et al, 2003). 1n this approach, a prior distribution was assumed from the number of failures and dam-years for all large dams {according to the !COLD definition) identified in the NID and NPOP databases, Failures identified as 'infantile failures' in NPDP were excluded and only dams built since 1900 according to NID were used for total dam-year calculation. Under these assumptions, the total number of failures for all large dams for 1900-2005 was 84 with a total of 260,960 dam-years.
This corresponds to a point estimate of the failure rate equivalent to 3.2E-4/dam-year. A distribution was fitted around this mean. The number of dam failure events was modeled as a Poisson distribution for which its conjugate prior was assumed to follow a Gamma distribution (i.e.. the conjugate prior in a Gamma-Poisson model). The staff, based on judgment, chose a Gamma distribution with the point estimate obtained from the large dam failure rate above and a 51h percentile corresponding to 1 E-5/dam-year. With these assumptions, the staff obtained a prior Gamma distribution with parameters a= 0.8333 and~= 2589, which has a 5th percentile equivalent to 1 E-5/dam-year and a 95th percentile corresponding to 1 E-3/dam-year. The staff updated this prior distribution with the data used to obtain the large rockfill dam point estimate (e.g., 6 failures in 21,490 dam~years) to calculate the posterior distribution. The resulting posterior has a mean of 2.BE-4/dam-year, a 51~ percentile of 1.3E-4/dam-years, and a 9511' percentile of 4.8E-4/dam-years (with parameters a = 6.8333 and 13.= 24,079). Figure 2 shows both the generic large dam prior and the posterior specific to rockfill dams, Conclusions The staff estimated generic dam failure rates for large rockfill dams, which it considers applicable to the Jocassee Dam, as 2.BE-4/dam-year. Given the nature of the qata and the assumptions involved in narrowing the applicable failure events and subset of the U.S. dam population comparable to this specific dam, the staff performed a Bayesian analysis. Using available data on the domestic inventory of dams and dam failures, the range obtained varies between 1.3E-4/dam-year and 4.SE-4/dam-year (51h - 95th percentile) around a mean of 2.SE-4/dam-year..
A literature review performed by the authors for statistical studies of dam failures appears to corroborate this conclusion. Such studies were found in Baecher et al [ 1980}, Martz and Bryson (1982), Donnelly (1994), ICOLD (1995}, Foster (2000a}, and Foster et al {2000b}.
of FOIA Appeal 2013-009A Update Letter SENSII1V~ INFGRMATIQ~,j -OFFICIAL U~
Figure 2: Failure Rate Probability Distributions Used in Bayesian Updating References 0000,.------,-----.------,-----.---~
4500~
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Baecher, G. B., M. E. Pate, and R. De Neufville (1980), "Risk of Dam Failure in Benefit-Cost Analysis," Water Resource Research, 16(3), 449-456.
Martz, H.F., and M.C. Bryson (1982), "Predicting Low-Probability/High-Consequence Events,"
Proceedings of the Workshop on Low-Probability/High-Consequence Risk Analysis, June 15-17, 1982, Arlington, Virginia.
Donnely, R. (1994), Nlssues in Dam Safety, ACRES International Innovations Autumn Edition":
http://www. hatch. com_ cn/H atchenergy/ In naval ions/ autumn 2004/f eatu re. ht m I ICOLD (1995), "Dam Failures Statistical Analysis," Bulletin 99, International Commission on Large Dams.
WCD (2000), ~oams and Development: A New Framework for Decision-Making - overview," The Report of the World Commission on Dams.
Foster M, Fell R, Spannagle M (2000a), "The statistics of embankment dam failures and accidents," Canadian Geotechnical Journal, 37, 1000-1024.
Foster M, Fell R, Spannagle M (2000b) "A method for assessing the relative likelihood of failure of embankment dams by piping." Canadian Geotechnica/ Journal, 37, 1025-1061
-sENSI flve-tNf:OS:MAT10N Or"EIG+At USE ONl.¥ 7
of FOIA Appeal 2013-009A Update Letter C.L. Atwood, J.L. LaChance, H.F. Martz, O.J. Anderson, M. Englehardt, D. Whitehead, and T.
Wheeler (2003), *Handbook of Parameter Estimation for Probabilistic Risk Assessment."
NUREG/CR-6823, US NRC.
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14
,. of Update to FOIA 2013-009A July 19, 2010 MEMORANDUM TO:
Benjamin Beasley, Chief Operating Experience and Generic Issues Branch Division of Risk Analysis Office of Nuclear Regulatory Research FROM:
Lois James, Chief /RA/
Probabilistic Risk Assessment Operational Support Branch Division of Risk Assessment Office of Nuclear Reactor Regulation
SUBJECT:
IDENTIFICATION OF A GENERIC EXTERNAL FLOODING ISSUE DUE TO POTENTIAL DAM FAILURES INTRODUCTION The NRC's primary function is to license and regulate the safe use of radioactive materials for civilian purposes to ensure adequate protection of public health and safety and the environment.
In performing this function, the Office of Nuclear Reactor Regulation (NRR) identified during a recent review of a regulatory action associated with an operating nuclear power plant (NPP) a higher than expected potential for both the external flooding hazard due to a potential dam failure and its associated consequences to the public health and safety and the environment.
Based on these findings, the Division of Risk Assessment (DRA) and the Division of Engineering (DE) at the Office of Nuclear Reactor Regulation (NRR) began evaluating the potential implications of these findings to other operating NPP sites by:
(i) evaluating the extent to which this hazard has been considered in the past via US NRC's regulatory framework (e.g., 10 CFR 50, Regulatory Guides, Standard Review Plan),
(ii) examining current design flood bases regarding dam-related external flooding issues, (iii) interacting with other federal agencies involved in oversight and risk assessment of dams, and (iv) considering whether this additional knowledge may translate into an increase in risk when compared to the previous understanding of this issue.
TECHNICAL ISSUE External flooding considerations involve a series of hydrological and non-hydrological factors that may impact a NPP site. Hydrological factors include site-specific extreme phenomena characteristics (e.g., high tides, severe storms, wave action) potentially causing flooding, while non-hydrological events include seismic activity and other causes. In both cases, there is a potential hazard due to the effect of hydrological and non-hydrological phenomena on man-made structures such as dams, levees, and dikes as contributors to flooding. Available guidance on dams from entities such as the Federal Energy Regulatory Commission (FERG),
of Update to FOIA 2013-009A US Bureau of Reclamation (USBR), and the US Army Corps of Engineers (USAGE) indicate mechanisms that may trigger the uncontrolled release of the reservoir impounded by a dam.
These generally include (i) overtopping of a dam due to severe precipitation-induced flooding, (ii) seismically-induced failures, (iii) breaches caused by internal erosion/piping phenomena, (iv) operational errors or mechanical failures, and (iv) combinations of these various mechanisms.
Failures other than severe storm and seismic events can be grouped into a subset often referred to as "sunny-day" failures, which can occur during normal operations (e.g., internal erosion and operational failures). Guidance from USBR clearly indicates that these "sunny day" failures may be higher contributors to risk when compared to low-frequency extreme events such as severe storms and earthquakes (USBR, 2010). Additionally, when compared to severe weather events, "sunny day" failures may provide less warning time for mitigating actions to take place. From discussions with these multiple agencies involved in dam risk assessment, it was concluded that the current state-of-art has evolved sufficiently to provide better risk estimates of such contributors.
REGULATORY FRAMEWORK The regulatory requirements for issues related to external flooding are found in Appendix A to 10 CFR 50 (CFR. 1971), where the General Design Criteria (GDC) is described. The GDC was developed to establish minimum requirements for the principal design criteria (i.e., set of necessary requirements to ensure public health and safety) for NPP sites similar to those already licensed. The General Design Criteria 2 (GDC 2) explicitly discusses considerations on the appropriate design bases for structures, systems, and components (SSCs) important to safety expected to withstand the effects of natural phenomena such as flooding. In some cases where the license for a specific reactor site was issued prior to the development of GDC 2, licensees have used criteria similar to GDC 2 to cover natural phenomena considerations in their original license submittals. GDC 2 states that:
"The design bases far these SSCs shall reflect: (1) Appropriate consideration of the most severe of the natural phenomena that have been historically reported far the site and the surrounding area, with sufficient margin for the limited accuracy, quantity and period of time in which the historical data have been accumulated, (2) appropriate combinations of the effects of normal and accident conditions with the effects of the natural phenomena, and (3) the importance of the safety functions to be performed."
In terms of regulatory guidance, four Standard Review Plans (SRPs) in NUREG-0800 (ML0D3740388, ML062260222, ML070730405) and Regulatory Guide 1.59, "Design Basis Floods for Nuclear Power Plants," (ML003740388) include specific guidance on external flooding at NPPs due to potential dam failures. The guidance provided in Regulatory Guide 1.59 explicitly covers hydrologic and seismic-induced dam failures, as well as considerations for combinations of lesser events.
Upon review by NRR staff of the above references, it has been concluded that existing NRC requirements and guidance is ambiguous on whether certain failure mechanisms such as internal erosion or operational errors should be explicitly considered, which have commonly not been the focus of safety analyses performed for operating sites. In part, an assessment of the risk contribution due to Msunny day" failures may have not been consistently performed due to a lack of understanding of its impact on the safety margins of existing NPP sites. Further guidance can be developed with additional understanding of the actual contribution to NPP risk due to "sunny day" failures individually and in combination with other mechanisms.
2 of Update to FOIA 2013-009A CURRENT DESIGN FLOOD BASES A detailed analysis of dam-related flooding potential and its consequences in the licensing of operating NPPs is limited in the available documentation, which consists primarily of the Final Safety Analysis Reports (FSARs) and the Individual Plant Examinations for External Events
. (IPEEEs) for individual sites. lt is clear however, that emphasis has been placed on the use of conservative screening assumptions to eliminate this flooding hazard from further consideration based on either bounding characteristics of other flooding phenomena, low initiating event frequency and/or sufficient advance warning in case a dam failure does occur.
In multiple FSARs and IPEEEs, dam failures are described as "not credible" (Fort Calhoun Station, Cooper Nuclear Station), "highly unlikely" (McGuire Nuclear Station), or "extremely unlikely" (Arkansas Nuclear One, Sequoyah Nuclear Plant, Watts Bar Nuclear Plant) by taking into account individual or combinations of severe events hydrologic and seismic events. From a preliminary review, at least four sites have considered quantitative dam failure rate: Oconee Nuclear Station (South Carolina), Cooper Nuclear Station (Nebraska), Fort Calhoun Station (Nebraska), and H.B. Robinson (South Carolina). All four sites considered failure rates in the range between 5 x 1 o*5/year and 1 x 1 o-5/year. Flooding requirements are considered for a number of sites, including the use of sandbagging and other mitigative actions which assume ample lead time for implementation. However, a preliminary review of the IPEEEs indicates that, since dam failures were excluded from consideration in most FSARs, its risk contribution has not been addressed to date.
RISK SIGNIFICANCE Due to the limited risk considerations available, NRR further evaluated the dam failure rates considered in the subset of IPEEEs mentioned above. As there were few reliable dam failure data sources when most estimates where derived, it was found that these analyses relied mainly on an estimate published in NUREG/CR-5042, "Evaluation of External Hazards to Nuclear Power Plants in the United States" (ML062260222). In turn, the data source for the dam failure estimate in NUREG/CR-5042 is "NSAC-60 Oconee PRA: A Probabilistic Risk Assessment of Oconee Unit 3" (NSAC/EPRI, 1984). Upon detailed review by NRR staff, it was concluded that the failure frequency value used for large dams in this publication was incorrectly underestimated by an order of magnitude which propagated to the other analyses (e.g.,
IPEEEs). This large difference was in part due to a commingling of different types of large dam population data and a restricted choice of failure data.
From this observation and the fact that most external flooding screening analysis were based on combinations of severe phenomena to screen out this initiating event without significant consideration of the ~sunny day" dam failure mechanisms, NRR staff performed two additional actions: (i) examined current NPP vulnerabilities to dam failure hazards and performed a qualitative assessment of sites more or less Hkely to be impacted based on available information (mostly FSAR and IPEEE information), and (ii) estimated a generic dam failure rate calculation based on the most up-to-date historical data for the specific subset of embankment dams which the NSAC-60 study was intended for (i.e., large rockfill dams).
In the first effort, a study was produced that resulted in a coarse screening and ranking of sites more vulnerable to this hazard (due to both upstream and downstream dam failures). U.S.
commercial nuclear reactors are located in 65 sites adjacent to streams, lakes/reservoirs, or coastal areas. A number of information sources were used to ascertain the location of dams and the corresponding impact to NPPs based on distance to the site and reservoir volume 3
of Update to FOIA 2013-009A impounded. Due to the lack of more up-to-date independent information, this study had to primarily consider design bases flooding elevation, historical flooding records, and flood routing results available from FSARs and IPEEEs submitted by licensees. From the 65 sites available, 45 sites were considered to be less vulnerable to potential dam fa/lures while 20 sites were considered to have a higher vulnerability. Of the remaining 20 sites, a qualitative assessment was applied to evaluate sites which could have high, medium, or low Impact due to a dam failure (see Table 1 ). Particular challenges observed are: (i) lack of independent up-to-date assessments of dam breach analysis and subsequent flood elevations at a site, (Ii) the extensive use of theoretical upper bounds used to approximate the frequency of extreme events such as severe storms and earthquakes (e.g., events with frequencies of 1 in 10,000 years or less), (iii) the complexity Involved in evaluating flood routing at specific watersheds, including estimating dam breach size and time for the corresponding flood wave to impact a site, and (iv) the effectiveness of the flooding protection barriers and site response due to uncertainties in the information above. The scope of this study was preliminary in nature and could greatly benefit from additional short term analysis to evaluate the overall risk at individual sites, since it is recognized that not all dam failures may be sufficiently large to impact a NPP and that significant distances between a site and the impounding structure(s) may attenuate the flood wave and increase the response time available. However it also provided an overview of the generic nature of this issue with a defined subset for further focused analyses.
In the second effort, a generic dam failure rate analysis applicable to a large rockfill dam of modern construction was performed to assess a point estimate and a range that can be supported by available historical data, along the lines of those performed in a subset of IPEEE submittals (ML100780084). Input information included (I) an assessment of the overall US dam population for those with features corresponding to a large rockfill dam, and (ii) a study of U.S.
dam performance information for failure events that may be applicable to this subset of the overall population. The best available databases were used to obtain the total number of dam-years for large dams and documented failures, which also provided insights into limitations and challenges involved In deriving failure rates using this approach. A point estimate calculation produced a value of 2.8 x 104/dam-year, providing a further check on the estimate previously used in the industry. Simple sensitivity analysis Indicates that significantly lower estimates cannot be reasonably supported by the use of historical data alone. Hence, while limitations in historical data represent a challenge to ascertain a more precise estimate, it is clear that screening this hazard exclusively via this methodology is not justified. Additionally, a Bayesian updatin9 analysis with the subset of dam-years and failures corresponding to rockfill dams was performed using an assumed prior distribution for large dams. This resulted in a posterior distribution with a mean of 2.8 x 104 /dam-year, a 5th percentile of 1.3 x 10"4/dam-year, and a 95lh percentile of 4.8 x 104 /dam-year (i.e., a narrow distribution around the mean value).
Additionally, a literature review of similar published statistical studies of dam failures corroborated the conclusion that a generic dam failure rate for large dams is in the order of magnitude of 1 in 10,000 dam-years.
From these two efforts, NRR staff has concluded that (i) there is an increase in the estimated frequency of a potential dam failure of an order of magnitude from the additional preliminary analysis performed, (ii) prior estimates used in the industry underestimated dam failure rates, (iii) multiple sites can be affected by the impact of dam failures, and (iv) the overall risk to NPP sites may not have been fully addressed due to inconsistencies in identifying and appropriately addressing significant failure modes for dams.
4 of Update to FOIA 2013-009A RECENT EXPERIENCE On April 28, 2006, NRC staff identified a performance deficiency involving the Oconee Nuclear Station (CNS) maintenance activities associated with the Standby Shutdown Facility (SSF) to facilitate installation of tern ora electrical ower cables. The im ortance of this find in is that (b)(7)(F)
ONS was issued operating licenses in 1973 (Units 1 and 2) and 1974 (Unit 3), prior to the publication of significant regulation (e.g., GOC 2) and guidance on external flooding hazards applicable to most of the industry. The licensing basis of ONS did not originally evaluate the consequences of a failure of the Jocassee Dam in the plant design flooding analysis. Flooding protection for the SSF was later added as a risk assessment enhancement obtained via insights the IPEEE submittal for ONS. However, after interactions with licensee, it was established that the original elevation (5 feet) to which the SSF flood protection was designed for would be exceeded based on more recent studies. These studies indicate that approximately 18.5 feet of waler could occur at the sitel(b){7)(F}
!after a breach of Jocassee Dam. In this case, the licensee has indicated that a loss of the switchyard, loss of the emergency power supply (hydro units), los ML0827 1
(b}(?}(F)
(b)(7}(F)
(b)(?)(F) ence, based on the varying plant configurations and the loss of the mitigating equipment listed above, the conditional core damage probability (CCDP) given a dam failure for ONS could be as high as 1. Given that ONS had originally used the NSAC*60 study which incorrectly derived a dam failure rate an order of magnitude tower than the NRR analysis indicates, additional reviews, analysis, and actions are expected to affect the licensee on this issue.
Additionally, an NRC inspection on March 2010 at the Fort Calhoun Station (FCS) identified an apparent violation for failure to maintain adequate procedures for flood protection at the site, as stated in its licensing basis (ML101670034 ). Since FCS is located in close proximity to the Missouri River, and its base plant elevation (1004 feet mean seal level (MSL)) is not far above the normal river levels, NRR is currently evaluating the flooding licensing basis with respect to severe precipitation events. Current NRC assessments of external flooding vulnerabilities indicates that all normal plant equipment fails when floods reach 1010 MSL, and that essential safety*related components fail between 1010 MSL and 1014 MSL. Review of flooding extrapolation updates performed by USAGE for the FCS region indicate an increase in potential elevation for floods with a return period of up to 500 years, not previously considered by the licensee (ML101670034). FCS is also located downstream from several large dams, and its IPEEE su mitt t tates that failure of the lar r
m wo I use a floo wave that would reach the site (bl(7)(F)
Based on the increase in estimated flood levels, the use of NSAC*60 dam failure rates, and the recent experience with flood routing analysis in the ONS dam failure studies; a potential for an increase in risk due to this hazard is also expected at the FCS site (attenuated only by the distance to the set of dams located upstream). Furthermore, the original FSAR and IPEEE submittals for Cooper Nuclear Station (CNS) formed the basis for the external flooding analysis performed at FCS. As indicated above, CNS {which is further downstream from FCS) has also used NSAC-60 as a basis and screened this hazard as "not credible."
5 of Update to FOIA 2013-009A Since additional information is limited for other sites, there is a potential that additional regional flooding studies and improvement in the state-of-art assessments of the impact of dam failures at NPP sites may also Indicate an overall change in risk not previously considered in other original studies, applying to more than the facilities identified above.
RECOMENDATION NRC's primary function Is to license and regulate the safe use of radioactive materials for civilian purposes to ensure adequate protection of public health and safety and the environment.
Considering the existing regulatory framework, the safety significance of the issue, the risk increase considerations, and the generic implications provided; the recent information and experience with dam-related external flooding vulnerabilities indicates an issue that needs to be properly addressed to support NRC's mission.
Under these considerations, we recommend that you initiate expeditious action to examine the dam-related external flooding issue under your Generic Issue Program. NRR/DE and NRR/DRA will maintain interaction with your staff. as needed, during the resolution process, and initiate appropriate action in accordance with the findings from the final resolution of this generic issue.
If you have any questions, your staff may contact George Wilson (301-415-1711), Lois James (301-415-3306) or Meena Khanna (301415-2150).
REFERENCES Baxter, Dave, Duke Energy Carolinas, LLC, letter to Joseph G. Giiter, U.S. Nuclear Regulatory Commission, September 26, 2008, ADAMS Accession No. ML082750106.
Nuclear Safety Analysis Center/Electric Power Research Institute, "NSAC-60 Oconee PRA: A Probabilistic Risk Assessment of Oconee Unit 3," Palo Alto, CA, 1984.
US Bureau of Reclamation, "Dam Safety Risk Analysis Best Practices Training Manual,"
Version 2.0, U.S. Department of the Interior, Technical Service Center, Denver, CO, 2010.
U.S. Code of Federal Regulations, "Criterion 2--Design bases for protection against natural phenomena,~ Part 50, Appendix A, Chapter I, Title 10, "Energy."
U.S. Nuclear Regulatory Commission, "Design Basis Floods For Nuclear Power Plants,"
Regulatory Guide 1.59, Rev. 2, 1977, Agencywide Document Access and Management System
{ADAMS) Accession No. ML003740388.
U.S. Nuclear Regulatory Commission, "Evaluation of External Hazards to Nuclear Power Plants in the United States," NUREG/CR-5042, Lawrence Livermore National Laboratory, December 1987, ADAMS Accession No. Ml062260222.
U.S. Nuclear Regulatory Commission, "Probable Maximum Flood (PMF) on Streams and Riverst NUREG-0800, Standard Review Plan, Chapter 2, Section 2.4.3, Rev. 4, 2007, ADAMS Accession No. ML070730405.
6
. ' of Update to FOIA 2013-009A U.S. Nuclear Regulatory Commission, "Floods,R NUREG-0800, Standard Review Plan, Chapter 2, Section 2.4.2, Rev. 4, 2007, ADAMS Accession No. ML070100647.
U.S. Nuclear Regulatory Commission, "Potential Dam Failures.ft NUREG-0800, Standard Review Plan, Chapter 2, Section 2.4.4, Rev. 3, 2007, ADAMS Accession No. ML070730417.
U.S. Nuclear Regulatory Commission, "Generic Failure Rate Evaluation for Jocassee Dam,"
March 15, 2010, ADAMS Accession No. ML100780084.
U.S. Nuclear Regulatory Commission, "EA-10-084, Fort Calhoun Station, Failure to Maintain External Flooding Procedures: May 27 2010, ADAMS Accession No. ML101670034.
7 of Update to FOIA 2013-009A OFF
-RELATED INf=
Table 1. Qualitative preliminary assessment of dam hazard vulnerabilities for operating NPPs Site Name State Area Body of Water s:creening Arkansas Nuclear AR Stream Arkansas River HIGH Fort Calhoun NE Stream Missouri River HIGH McGuire NC Stream/ Lake Catawba River/ Lake HIGH Nonnan Oconee SC Stream/ Lake Keowee River/ Keowee Lake HIGH South Texas TX Lake Cooling Pond HIGH Watts Bar TN Stream Tennessee River HIGH Beaver Valley PA Stream Ohio River MEDIUM Browns Ferry AL Stream Tennessee River MEDIUM Columbia WA Stream Columbia River MEDIUM Cooper NE Stream Missouri River MEDIUM Peach Bottom PA Stream Susquehanna River MEDIUM H.B. Robinson SC Lake Lake Robinson MEDIUM Sequoyah TN Stream/ Lake Tennessee River/
MEDIUM Chickamauga Lake Three Mile Island PA Stream Susquehanna River MEDIUM Vermont Yankee VT Stream Connecticut River MEDIUM Hope Creek/Salem DE Stream Delaware River LOW Indian Point NY Stream Hudson River LOW Prairie Island MN Stream Mississippi River LOW Surry VA Stream James River LOW Waterford LA Stream Mississippi River LOW 8
of Update to FOIA 2013-009A Table 1. Qualitative preliminary assessment of dam hazard vulnerabilities for operating NPPs Site Name State Area Body of Water Arkansas Nuclear AR Stream Arkansas River Fort Calhoun NE Stream Missouri River McGuire NC Stream/ Lake Catawba River! Lake Norman Oconee SC Stream! Lake Keowee River! Keowee Lake South Texas TX Lake Cooling Pond Watts Bar TN Stream Tennessee River Beaver Valley PA Stream Ohio River Browns Ferry AL Stream Tennessee River Columbia WA Stream Columbia River Cooper NE Stream Missouri River Peach Bottom PA Stream Susquehanna River H.B. Robinson SC Lake Lake Robinson Sequoyah TN Stream/ Lake Tennessee River/
Chickamauga Lake Three Mile Island PA Stream Susquehanna River Vermont Yankee VT Stream Connecticut River Hope Creek/Salem DE Stream Delaware River Indian Point NY Stream Hudson River Prairie Island MN Stream Mississippi River Surry VA Stream James River Waterford LA Stream Mississippi River Accession Number* ML101900305 OFFICE NRR/DRAIAPOS NRR/DEIEMCB NRR/DE/EEEB NRR/DRNAPOB NAME FFerrante DATE 7/912010 MKhanna GWilson 711512010 7112/2010 OFFICIAL RECORD COPY 9
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gJacom Continuing Education and Development, Inc.
9 Greyridge Farm Court Stony Point, NY 10980 P: (877) 322-5800 F: (877) 322-4774 info@cedengineering.com
m US Army Corps of Engineers ENGINEERING AND DESIGN of FOIA Appeal 2013-009A Update Letter EM 1110-2-2300 30 July 2004 General Design and Construction Considerations for Earth and Rock-Fill Dams ENGINEER MANUAL of FOIA Appeal 2013-009A Update Letter EM 1110-2-2300 30 Jul 04 IHCLIHEO 011: VERTICAL OIIAIH IF!
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1} Phased crest raise with parapet to maintain traflk flow on crest during construction.
- 2) Wall details to be adapted to existing embankment geometry and zoning. Impervious, filter, slope prot~tion, and other critical clements to be extended upward as necessary.
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