ML16235A166

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FOIA/PA-2016-0532 - Resp 2 - Final, Agency Records Subject to the Request Are Enclosed and Are Already Available in Public ADAMS or on Microfiche in the NRC Public Document Room
ML16235A166
Person / Time
Site: Indian Point  Entergy icon.png
Issue date: 08/16/2016
From:
NRC/OCIO/CSD/FPIB
To:
References
FOIA/PA-2016-0532
Download: ML16235A166 (62)
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Text

Elkhiamy. Sarah

Frqm:, Pinson, B'ram:lon B:

Sent: Thursday, January 28, 2016 2:16 PM To: RlA.l;LEGATJON RESO.URCE Cc: WARNEK, .NICOLES; Schussler, Jason E; DENTEL, GLENN T; DEFRANQSCd, ANNE E SubJe¢ . **Sensitb~~ Allega~iOir Mat~rfal~* RI~2Q15-A-QQ74 RAC contrq! tqom habitabjllty wi:itelJp

.Attachments:* IP3 CR h~liitability.docx -

    • Updated to remove specific distances. **

Atic1cbed is th~ technical respon~e regartjing the qu~stions sun:o~nding cQntrol rqoro _t)atiit~bilify anq susceptibility to methane ih,.leakage. The document was prepared by the region and edited by Individuals_ from NRR's Plant Syste1J1s _Branch **

RI, l)l'ti>, Bra11ch 2 (610)_-337-5390 1

pipeiines:

Tbere. is:one afl<tltkmal issuf3, from another sourr;e, .related' to .thes.e gf:ls lines a.nd fhf1( cpncerris

,th:e prote9tion. Qftbe c;ontr9/ an<! switchgear r9Qms lo<;ated. al:)oµf$"$0 fef}t from the .exiWng-ga$

lines; NRG regulations (10 CFR 5o; Appen.dix-R and Appendix A, Criterion 3, 4, and 19) anil gµidance

. (Re_gulatory Guides 1. 78, 1.-9.1' and 1.1962) requite protection 6-orr,- intetn;;il and external eyentS that could Impact the operability of the cohttol tooth and other .sscs. MyrevfeW ofthe Current Ucensing Basis (CLB) ~s defined ih 10* Ci=k .M.3 indicates there is no prote,ction fo{the control room and other vital structi.Jres in the_ event ofa methane gas leak from the' existing 64-year-old gas transmission lines. A small leak coMd totally disable the control room and its personnel arid vital SSCs 'necessary to* safely shut down the reactor. The .CLB documents di~cuss the potential ofchlcitihe gas and other toxic gasses located more than a mile from the control' room bi.It totally ignore t/Je ppt~ritia/ for a ga~ leak that 9perates coritin'i.Jously within 380 feet of.the control room:

Some ofthes_e analy~e.s, still part of the CLB;, qssume the pr~sence of non-existenf autQmgtic gas iin~ /splafioo v~lve~. ShQuld a /eq_k ocr;ur*and undetec~e.d metl)~mtl cpncentration~ ent(lr the control rppm, thfs couk:J dis?.ble. bQth the controls an(f operatl<;m personnel and have a severe impact on tbe. on th~ ability to $afely shut dQwn the plant; NRC Response:

The staff has evaluated the potential for* natutai gas fo disable opetafors .in the GPnfrol rtiom ~nd concluded that the potential* is negligible. The NRC gu'idance* cdntained ln*. Regul_afofy ~uid~

1.78, "Evaluating the*Habitabiiity of:~ NuClear Power:PlaritCohtrol Room dunn*g a* Postulated Hazardous Cherhical Release,."- Revision 1 (ML0131000_14), sp*et:ifies consklerations In evaluating the .control room .habitability:; includin~ the dista~ce from the control roQitr, the quanti~ of the. hazardous cheniical,.the atmt>spheric dis*persion of the release, tl:\e. toxicity, the (ibility tc;> detect the". release!. and the isol~tion of the oontroT room*. Alth6ug,h the pipei'ine is

.relatively* close and could release a large quantity .of natural,gas,.'the gas would be unlikely to re~ch the control room;, if it did reach the ,control roan\ the natural gas has low toxicity;* and the g~s is. detectable by its odor at low c*oncentratiblis, whieh woula allow operators tD' isolate the control room.

The. nalural gas would be unlikely to reach the control. room intake because if its low. density. and Jf1e disfa('lce sep;:irating the pipeline from the.control room air intake. The density of'natural gas (rnethane) is sjgnlfica_ntly l~ss th~n-.the density of.air ~t t.he s~me temp!3rature. which will c;illow fo.r nati;iral.gas fo qµiGkly di!?sipfite upwgi_rd .intq fh~ cit1J1qi:;ph*~re jf g l~al< vv.a~ to occµr. TJ:i_e.

  • ciistance_ betwe~o the cpntrQI mom *air intake aflndian PdinLUnit *3.(fP$} and. the. ga§. pfpeih1e~ i~
  • greatei'fhan 5oott, providihg: ari additional .barrier* as.the gas wouid nave fo_ travel a slgnittcant distance.at a relatively rc>w,elevation in oraen to pos~.a.. risk.:of.enterin~rthe control toohi.afr inta:ke'

If natural gas were to atcumulate, it is not toxic at low concentrations, unlike other compounds of concern. Rather, it is hazardous due to its explosive potential above eoncentrations of a few percent by volume and the potential to displace oxygen at even higher concentrations.

Therefore, the natural gas would have to reach the control room with little dilution to be hazardous, which is not credible.

Finally, the control room ventilation system provides for isol~tion of the control room air, if necessary. ihe control room air intake and the control room proper have, as required by NRC regulations, toxic gas monitors that are capable of dete~ting.gases such as chlorine, a_nhydrous ammonia, a.nd, indirectly, carbon dioxide. The oxygen deteqtors that are used to indirectly rn~asure carbon diqxide levels could also ~erve to alert operators if high levels of natural gas were to enter the control room air intake or control room atmosphere and c:Usplace the oxygen pres.ent. The control room cc:inta:in$ alarms that would alert op~rato~s if th~se toxi~ gases were detected, there was equipment trouble, or on a loss of power. Additionally, the natural gas that is transported through the gas pipelines at IP3 i$ odorized with sulfur containing compounds (mercaptans) that would allow detection of the natural gas by personnel on site, as well as operators in the control room, at low concentrations. This would allow operators to place the control ro~m ventilation in a 100% reci~culation mode that would prevent further ingress of outside air.

    • 00 a~ - *** 0 *I** ~ . . . . . . <!<* .. a , *o*1 a 0 .,,.,..., ... - . - .. - . * / * . . . . . . . ~ ..... , ............ ,' ; - - - ..**~***~****-**""""*:*_,,.. ......... -: ............ *, ' " " **~'"

Elkhiamy, Sarah

.From: Pickett, Douglas Sent Thursday, October 22, 2015 8:59 AM To: Mccoppin, Michael; Tammara, Seshagiri Cc: Miller, Chris; Beasley, Benjamin; Dentel, Glenn; Pinson, Brandon; Stuchell, Sheldon; Banic;

  • Merrilee; Cylkowski, David; Beaulieu, David; Carpenter, Robert; Wray, John; Thompson, William; Setzer, Thomas; Burritt, Arthur; Draxton, Mark; Pinson, Brandon

Subject:

Region I Requests Assistance RE: Indian Point ~cis Pipelines Attachments: **Sensitive Allegations Information** IP gas pipeline report for Rl-2015-A-0074;

    • Sensitive Allegations Material** Rl-2015~A-0074 RFI response Mike/Rao-Entergy's 2008 analysis of the existing gas pipelines concluded that a rupture of both pipelines would result in heat flux va.lues exceeding our threshold value of 12.6 kw/m 2 in portions of the Unit 3 protected ar~a. Paul Blanch's allegation included this aspect and Region I issued a Request for Information to the licensee to address this. The bulk of Entergy's response is attached. The remainder, plant procedures, is available and is currently on CD with the Region.

Region I has requested that we review the attached and let them know if we agree with their approach and whether we consider their approach appropriate and conservative. Are you able to assist us (again)?

Thanks - Doug Douglas V. Pickett, Senior Project Manager Indian Point Nuclear Gener:c;iting Unit Nos. 2 & 3 James A FitzPatrick Nuclear Power Plant Douqlas.Pickett@nrc.gov 301-415-1364 1

Bearde, Diane

-Fron): RiAL~EG~TION ~ESOURCE Sent: Thursday, Det:eniber* 10, 2015 3:44 PM T9: .Warne~. Nicole; Cri$den', Ctie.rie; t¥Jct.au-ghlin; Marjorie; Bearde, Dlane; Bolger, Allyce~

Galbreath, Stephanie

  • FW: 201s-a-0074-- ip pipeline - allegation sensitive F~m: alckett, Brice

$ent: Thul'Sday, December 10, 2015- 3:44:16 PM (UTc~os:OO) Eastern Time (US & Canada)

To: RlALLEGATION RESOURCE . .

Subject:

2015-a-0074 - ip pipeline - allegation sensitive Mike did concur - I owe him one response though - he a.sked if we could- acknowledge (in _a one-Jiner) about the c6nservatisms built into our.independent review of the issue (i.e. conservative assumptions. in the ALOHA

.model or the scenario to e,ven begin the mode!). I promised to re\ii_ew lhe NRR respons~/analysis t9 se~ it they indicated that in their response to Glenn/Branch 2 before I would be camfortable in that statement, even though it i~ highly likely true.

  • We can M tn~t head. o_n Monday.

Brice

  • Bearde, *oiane From: RiALLE~A11QN RESOURCE*

Sent: Thursday, De.tember 10, 2015 4:~1 PM

  • To: Warne!<, Nicole; Cri$Qen, Cherie; Mclaugl)lin, Marjorie; Beard:e, piane; Bolger, Allyce; Galbreath~ Stephanie F\,\!: RE: ~i<isting p!peline haz~r(;i eyal1,1~tiqn write-up for IPEC C!llegation From: 'Bickett, Brii::e .

Sent: Thursday, pecelll~r 1P, 2015 4:SQ':SQ PM (LiTC-OS:QO) East~rn T)me {us & canaqa)

To: R1All.EGATION RESOURCE cc: Dentel, Glenn

Subject:

RE;: RE: existing pipeline hazard evaluation write-up for*IPEC allegation

.1 attllally think we can C!t ,least hi~hlight that our ind~pendent review was.based Qn c_onserv~tive assun'fpti_ons an.cl approach since ri'lo says that Jn thi;? *intrc;>_~

Will see how to implement minor noodles to capture on Monday And that would satisfy mike On: 10 D~cemb~r 2015 1S:42, ,;J~iAL~~GATION ~ESQURCE" <~l)\LLEGATION.RES.QURCE@nrc;,goy> w.rqte;

_F,r~in: cfontel, _Glefin * . .

Sent: Thursda_y, December io, '2015 3:42:46 PM. (urc-os:oo) Eastern Time, (US & canada)

To: RiALLEGATION RESOURCE 0 CC: Bid<ett Brice * -

1.:;* . :'*. ~-, ~ '* _.': .; - : ' - ,- .... -* -- . . "

$1,1bj~: fW;, Rj:: ~istii:ig piP,eline h~zcndevall1C;t~i9nWrite-upfor IP.I;~ ~!lega_ti9r1

{J/e,,in D~Nr!.f Branch Chief responsible for oversight of Indian Point and FitzPafrick

.610~331~5233 f '-v) frO.m: McCQppin, Mic;hael

~nt: Tl)ursd;.iy, Qec~t:Jlper Q3, ioiS-3:54 PM Tp: tamrne1rci1. ~eshag!ri <Seshagiri.Tammara@nrc.gov>;*Oentel~ Glenn <Glenn.Dentel@nrt.go:V>:?Pickett, Oouglas <Oouglas.Pii::kett@nrt.gov>

Cc: Hollcrafi:) Zachar'f ~zathacy.H_olicrah@nrc.gov>

Subj~tt=~~-: RE: ~xJstin~ pip:e;ln~~-~~zarg ¢.lt'.cilµatiQn.Writ~-µp for: ~PECallegafio:i;-1 Folks,_

some_
rninof.edlts;*_as discussed bet\ive.en Glenn, Rao. ~fno. !:to~a'f. Plea:~e -f~etf(§~ \q .ma~~ ~ny
~cljfor!gl ~~tts ~l?: Y.91..1 §~~ fit 1

l\1ike Mccoppin, MBA, PMP Branch Chief, Radiation Protection &

Accident Cons*equences JRPAC)

Office of New Rea~tars United States Nuclear Regulatory Commission et Mail S.top: T7 -FO~

Office: T7-F18,

'ii. Ph: 301.41.5.6533 C~ll: l(b)(S) I

<-5l FAX: 301.415.5399

~- Email: :michae!.mccoppin@nfc,gov From: Mccoppin, Michael.

Sent: l).1esday, Decemb.er Oi, 2015 2:5$ PM To: Tammara(Seshagiri . <Seshagiri.Tammara@nrc.gov>;

Dentel, 'Glenn <Glenn.Oentel@nrc.gov;.;

Pl~kett, Douglas.<Dotiglas.Pickett@nrc.gov>

C~: Holl.crcif:t, Zach~rv <Zachary.HoHcraft:@nrc.gov>

Subject:

RE: existing pipeline hazard* evaluation wrltecup for IPEC allegation lmpO.rtance: High Rab... niy edits are included.

Thanks,.

Mike Mc.Coppin, MBA, PMP Branch Chief, Radiation Protection &

_Acqicjent Goos~q!J~!:l~S, (RPAC)

  • Office .of New. Reactors.

2

United States Nuclear Regulatory Commission r=!; Mall Stop: T7-F03 Office: T7-F18 ii Ph: 301.415.6533 Cell: l(blt5l I

~ FAX: 301.415.5399

~ Email: michael.mccoppin@nrc.gov 3

Warnek Nicole From: R1ALLEGATION RESOURCE Sent: Thursday, December 10, 2015 3:43 PM To: Bickett, Brice; Wamek, Nicole; Crisden, Cherie; Mclaughlin, Ma~orie; Bearde, Diane; Bolger, Allyce; Galbreath, Stephanie

Subject:

FW: RE: existing pipeline hazard evaluation write-up for IPEC allegation Attachments: Indian Pt~Rao's Allegation_analysis_writeup (w corrections 12-3-15) (00000002).docx; IPEC_exisitingyipelines_impact_writeup_redac.pdf From: Dentel, Glenn Sent: Thursday, December 10, 2015 3:42:41 PM (IJfC-05:00) Eastern Time {US & canada)

To: RlALLEGATION RESOURCE Cc: Bickett, Brice

Subject:

FW: RE: existing pipeline hazard evaluation write-up for IPEC allegation Glenn Dmtd Branch Chief responsible for oversight of Indian Point and FitzPatrick 610-337-5'.!33 (w) from: Tammara, Seshagiri Sent: Monday, December 07, i015 4:11 PM To: Mccoppin, Michael <Michael.McCoppin@nrc.gov>; Pickett, Douglas <Douglas.Pickett@nrc.gov>; Dentel, Glenn

<Glenn.Dentel@nrc.gov>

Cc: Hollcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

FW: RE: existing pipeline hazard evaluation write-.up for IPEC allegation All I have run ALOHA with maximum operating pressure of 750 psia instead of 67 4 psi a and the change in results are documented as follows:

  • 7 With 67 4 psia the estimated distance to 1 psi is (bl< l<FJ and to 3 psi is (bJ(?J<FJ With 750 psia the estimated distance to 1 psi is and to 3 psi is With 674 psia the estimated distance to 31.5 kw/m 2 , 12.6 kw/m 2 , and 5 kw/m 2 respectively arel(b)(?)(F) l(b)(7)(F) I ,__________.

With 750 psia the estimated distance to 31.5 kw/m 2 , 12.6 kw/m 2 , and 5 kw/m 2 respectively arel(b)(?)(F) l(b)(7)(F) I ----~

Thanks, Rao From: Tammara, Seshagiri Sent: Friday, December 04, 2015 9:27 AM To: Mccoppin, Michael <Michael.McCoppin@nrc.gov>; Pickett, Douglas <Douglas.Pickett@nrc.gov>; Dentel, Glenn

<Glenn.Dentel@nrc.gov>

Cc: Hollcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

FW: RE: exis_ting pipeline hazard evaluation write-up for IPEC allegation 3

JVlikeil:You~/~leh,:

ram orjcblC?l Ifrpm Dec.a, 20.15 throµgh Jan .18 1 2015* and l(bJc~> . I Mike a'ttached afld .transmitted the above*file ye_sterda,y; In case there is. a FOIA reqiJesf, I haveidentifi.ed in yellow/(ed the potential resuJts:

that may be r~da¢t¢d; ~m.d attached that .scanned file (.pdf) for your convenience ahd easy referral.

'Thanks, Raq*

From: McCopjJiri, Michael Se{lt: l'hµrsday, D¢i:ember o3, 20i5 .3:54 PIVi.

To:.Tamm~ra, Seshagiri <Seshagiri.Tammara@nrc.gov>; pentel; Glenn <Glenn.Dentel@nrcgov>; Pickett, Douglas

<Douglas.Pickett@nrc.gov:;.

Cc: Hollctalt; Zachary <Zacllarv.Hblkraft@nrc.gov>

Subje~: R.E: R~: existing pipeline haz~rd eva*luaticm""'.rite~up fQdPEC all¢gation FoJKs, Some m_inor ~Qits_ as disc~s~~d b~tween* Glenn, Rao, anq I tqqay. Please f~et free to make ;~ny ~ditoriat edits.

.as you' see fit Regards, l\1jl~e McCoppi_n, MBA, PMP Branch Chief, Radiation p*rotection &

Ac;:cident ¢onseque11ges (RPAC)

_Qffice ;af N~wRea~t9r$

United States Nuclear Reg*uratory Commission

  • ~~: M~il Stpp; 17-fP~

Office: Tl-F'.1.~

tt Ph: . 301:415,6533 Cel_I: l(bJcsi I

~ f:M: 3Ql.41S ..53~9 1'!* E;maii: _rnicha~L mccoppi!l@nrc:gov

.F_r~r:n: Mc:Coppin,, llJIJcfiae!

'se.r:it: T~_esday, December oi, 2()15 2:55 PM To: Tammara, Seshagiri <Seshagiri.Tammara@nrc.gov>; Dentel, Glerih <Glenn.Dentel@nrc.gov>; Pi.c:Rett, Do~glas

<Douglas.Pickett@nrc.gov>. * * * * ** * - *

  • Cc: Hrillcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

  • RE: existing pipelin.e hazard ev.aluation write~up for IPEC allegation hljportance: High Rao ... my edits are included.

Thanks,

  • Mike l\1cCoppin, MBA, PMP Branch Chief, Radiation Protection &

A~ciq~nt Co~sequences (RPA,C)

OIVJSIO~ Qfr SITE_ SAFETY AWD ~NV!RONM£NTAL !tNAL'VBlS Office of New Reactors

.United Slates Nucle~r Regulatory Cqmrnission

!'. Mail Stop: T7 ~F03 Office: n::F1a:

it Ph: 301.415.6533 cen: l(b)(S) I FAX:' *301A15.5399 Email:** michael.mccoppin@nrc.gQv

Confimiatory Analysis of Allegation concern .Evaluation*

.Of Existing Pipelines Rupture 1m*pact At Indian Poirit Energy Center (IPEC)

  • INTROQUCJ;ION Ttie licensee, _Entergy, provided*a response to NRC Request for Information (Rl-2015-A-0074).

As. *a part 9f fhe .staff;s review and: ~valuatiQn of the response and associated, attachment arid .

en.Glosure, the NRC. staff perfortned independent confirmatory calculations.to ascertain the re.asonability of approach, assumptions .and *methodology that Entergy used in their evaluation of consequences:fot the consideration of resolving the concerns raised in this* RI. The staff's confirmatory calculation$ include the detetminat_ion of the distance; to *1 psi 9verpressure (!ue to potential release of nat~ral gas and ~xplosion at~!;\~ source of release, .c;lue tp vap_or clo_uc;I explosion, and distance to pot~nti~I he,~t flux of 12.6 kw/m 2 due to re!e.a~e of gas as a jet fire.

SU~MARY OF E\IA.L.UATIQN Entergy evaluated tlie p_otential hazards to safety-related structures, systems, 'and components (SSCs).arid also SSCs important to safety (SSC ITS)'usirig the BREEZE-computer model with reasonable approach and assumptions. *Tne staff performed independent.confirmatory calculations with conservative assumptions and rationale u$ing RG *1.91 *methodolqgyfor source expJqsion and also us~dt_he ALOHA ¢omputermod_el for vapor plume explosion .. Tne staff us~d the Al-O_HA. rnm;lel to _perform the c_onfirmatory calculations to determinE!;

1) .OJstaor;e to 1 psi overpr~$st1r.~. ~u~ toJelease and potentiai at $.O_t;irce *(af pip~ 11Jptµre),

2} Distance to 1 p$1 ovewressure due to delayed vapQr cloud. expiosicm, * *

3) Distance .to neat flux of 12.6 kwtmt*from n:atural gas release as jet fire.

The staff's independent eonfirniatory calbulatio"h :restilts are based on. h!ghly eonsetvative assumption and ratfonale ~Y modeling tne g~as:release rate for the potential explosion at the:

source. The rupture of the pipeline is assumed to* be iocated at the closest SS.C. Sim~e the pipeline is buried underground, anaveragerelease rate,.*ascalculated using ALOHA to aetermirte total amount of gas released over tfle time period fo empty' the pipeline, results in a calculated distanee to 1 psi. overpressure of (b)(7)(F) In 9eneral 1 the review criteribn of 1_ psi overpressure prQvides a margin to failure qf safety related SSCs. The .safety-relatec;t sscs. are de$ign~d to withstand overpressur~ of 3 psj or more.without lo?s of th~ir safety functions., ln or.q~r: to esti111~teJh.e di~tance to pol~Dtiaf 3 psi oy~rp.r~ssure* -using the same average releas~

r~_te, the diSt!il}Ce to S p~i overpres~~r:e *is c~lct,1la'teq (q J;Je \bl( l.<Fl 7

The staff's ana'lysis of the distance fa .overpressure of 1 psi duefo a delayed vapor cloud.

explosion assumed c'Drigestion .in the area of release. The.results extend the 1 psi

<:>verP.res.sure to irnp~qt ,some: safezy-related sscs and sscs .importantto safety. However, lhe*

overpr~ss~rn diq not .~xc~ed*-3: psJ a.t ~oy c;ji_~t~n_~ (tp any.$SCs), A se_nsitjyity-~r:i~_l_ysi~, whi_ch,

SENSIT11t! - Sl!!CtJl!lft ft!t*fEB 1Nf6RMMle" *

  • .,. ~ -

more realistically, assumed *no congestiorrin the area, resu.lted in no 1 psi overpressure at any distance due'to vapor cloud explosion, Using the ALOHA_m9del, the:staff calculated .that: the thermal rcadiation lewel of 12.6 kW/m 2 wauid extend to a. distance *of <Rl(7)CF)

Based on the results offhe confirmatory analysis, th~ .staff concludesJhat tne safety ~elate~

SSCs, as well as SSCs important to safety, would potentially be-exposed to 1 ps_i overpressure, and a few SSCs*im_portant to safety may.be exposed to heat flux of 12.6 kw/m2 ! which is comparable to the licensee's conclusions.

TECHNICAL EVALUATION The staff performed an independent confirmatory analysis based on the rupture of th.et existing 30.:inch natural gas pipeline, which consist~ of about 6 miles of pipeline between isolation va_lves. The analysis .ass1.1med that a ruptµre of the na-tural gas pipeline m;:iy re~ult in ari unconfined explosion or jet flame at the source or in a. delayed vapor clpud explosioi:i downwin~t For the assessment of an unconfined explosion, the staff used RG t.91 methodology to calculate the minimum safe distance due to the source explosion. For the jet flame and delayed vapor Cloud explosion, the staff used the ALOHA chemical release modeling computer code to determine the hazard impact distances *to compare with the actual distances to SSCs related to safety or SSC ITS, in ordl3r to assess the impact potentiaL The ALOHA code is used to c~lculate the amoun_t' o.f methane release.d for ,the scenario considered, using conservative 11\efeorolc;>gic~I conditions consisting of ~n ~s$um¢d wind speed of 1. mis in the direction of the SSC, F stability, 25 deg, C a.mbient temp_e,ra.ture, clQlJd cover of o.~ and relative humidify, of SO%. Open t!Ptmtry Qrour:icl ro:ughness condit_ions m_9deling ~st;umptions were chQs~o a.s befog appropriate for the location.

Explosion The ALOHA cade mooel for an explosion-s_cenario conservatively estimated the *gas release:

from a pipe *rupture at the dose.st. location to an SSC by considering the length of pi'peline to be 6 miles, with the .rupture creating a hole equivalent to the dia"rrietef of-the pipe (30 inches diameter) at a maximum .~pen:lting pre*ssure *of. 674 psia. The calculation resultS gn/e an

.estimated total methane release amount over time (to caleulate the average release rate) based on.

the closure of the isolation valves following the rupture, assuming'that the entire vollJm~ of-gas in the pip~line seqtion between the clo~ed valve.s is, b.eing releas_ed; Assµ_ming the _average reiease r~te, and determining the tNT-*equivalent amounrwith a yieid taet<)r of 0;05: (WTNT> {equation given below), the minimum safe distance* (d> to 1 psi overpressure is *calc~i~tedby using RG 1.91.methOdology as follows:* *

..SENSITl\1E seett~IT(l!l!LATl!!t> fNpiO"~Afi6r*

wtNT= (Mf

  • DHC
  • Y)/4500 where WTNT= TNT equivalent Mass, kg Mf = Mass of vapor, kg DHC =Heat *Of combustion, kj/kg (50030)

=

Y Yield Faqor (0.05) and d= 4.5 * (w) 113 where.

d= minimum safe distance (ft.) to 1 psi overpressure w= TNT equivalent mass in pounds As. the pipeline is buried underground, an average rate of gas release based on total amount of ga$ release~ over the time period to empty the pipeline, as calculated u*sing ALOHA is assumed. Using this average gas release rate, the distance to 1 psi overpressure.was I

~alculated to be l(bJ(7J(FJ Genera!ly the ~afety-related S~Cs are designed to withstand overpresi;ure of 3 psi or more. In ord~r to estimate the distani;e to potential 3 psi overpressure, usin the same average release rate, the 9istance to 3 P.si overpr~s$ure is calculated to be (b)(7)(F)

The staff's analysis of the distance to not exceed an* overpressure of 1 psi due to delayed vapor cloud explosion assumeq congestion iri the area of release, which would represent dense forest or bui.ldings. which *enhance gas c;iccumu.lation 9ue to pot~ntial confinement. The re.suits extend the 1 psi' overpressure distance to impact some safety-related SSCs and *sscs important to safety. However, the ov_erpres.sure did notexce~d 3 psi ~tany Qistance (for ~ny $SCs). These resv!ts are comp~r;aqle to th.~t of the !icense~;s ;analysis results. A sensitivity analysis, which*

rnore realisticall¥ assumed no conges~ion in the ~m~a. res.ulted in no 1 psi overpr~ssure at einy distance due to vapor cloud expJosion.

Jet Fire The ALOHA code for jet fire scenarios was run conservc;itively f pr the pipe rupture at a loGatioo closes.t to an.SSC qy considering the length of the pipeline between isolation valves to be 6 miles, with rupture creating a hole: equivalent to the diameter of the pipe (30 inches diameter) at a maximum operating pressure of 674 psia. Methane is assumed to be released from the.

ruptured pipe.as a flammable gas and is assumed to t>e burnin9. The ALOHA ca*rculation resuJted in a maximum burn rate as well as an estimatep total amount burned over time, based on clqsure of the !~qla~ion valye~ following the. rup~ure. Based on the assumption that the entire voiume of gas in th*e pipelin_e sec;tlon between the clP5ed vatve.s is being release.d, the qistances to tt:iermal r~cli;ation le~~ls of 31.5 kW/m2 , 12.6 kW/m.2-; and 5.0.k.W/m2 calcuiated by ALOHA are l(b)(?)(F) . Ir~spe¢tively, A few s.afety related sscs ~nd SSCs important to safety may he impacted. 'These resuJts are, CQl)sisteri\ With th~ 1lce11s~e*~ ana.lysi~ results.

_ 4_.,,

CONCLUSION Based on the resulti;; of the -staff's independent confirmatory ~n:;ily$.is, the *~taff concludes that the safety-related SSC!S as well as SSCs important to safety would poten.ti~lly b~ ~xpos~cftQ 1 psi overpr~ssure, and a Jew -SSCs impprtant to safeJy may be exposed. to he~t f(u:!< of 12.6. kw/m2 , which is comparable to the iicensee's ~onclu~icm, A~hougb th~ licel'.ls.ee's pipeline h~zard impact eYalua.tion used different models, assumptions, and methodology than the staff (Jsec:t in its independent confirmatory ;1nalyses, the staff's results and conclusions are consistent w(th the iicens_ee's results and conclusions. Therefore, the staff considers the licensee's hazard impact evaluation to be reasonable and -ae:c~ptable .

.:-**--~.:.~.--~ ..:.... .

--~~ ..;.......:._.-:..;....;..:.~-----*----***--:.. __ ~~.;_;,..._;...;; .. ~---*--*. ...:..:....... ,.

Bearde, Dian~*

From: RlAL~EGATION RESOURC:E Sent: Thursday; Oetember 10; 2015 3:43 PM To: Bickett, B(ice; Waro~k, Nicol.e; Crisden, Cherie; McLc;iug~fin, M~rJ9rie;: Bear:de; Di_~ne;

'Bolger, Allyce; Galbreath, Stephanie

~ubj~ct FW: *RE~ existing pipellne hazard evaluation w~he:-Up for' IPEC allegation

.Atta~hments*: Indian Pt-Rao's Aliegation_analysis_wi'iteup (w cqrrec;tions q-~-15) {00000002).dbci< .

From: Dentel, Glenn Sent: Thursday, .December 10, 2015 3:42:46 PM (UTC-05:00) Eastern Tim~-.cus*& c:anada) to: R1ALLtGA110N RESOURCE

~: aickett, 6riq~- ' .. ' ' . .

Subjec:t: Fw: RE: ~isting pipeline hazard evaluation write-up for*IPEC aliegation Glenn Dentel B1:anch (:hief rt;>spon~ible for i.)versight qf h~~ian Point ~nd _FitzP~~rick 6'10-337-5233 (w)

Fr!)m: l\t1cCoppin, Micha.~J Sent: Thursday! December 03, 2015 3:54 PM' TQ.:.Tammar:a, s.eshagiri <:Se.shagir:i.Tarrirriara@nrc:gov>;. Dentel! Glenn <_Glenn.Dentel@nrc.gov>; Pickett, Douglas

<<Dougla~.Pickett@nrc.gov> * * - * * -

Cc: Hollcra.ft, Zachary<iachary.Hollcraft~nrc.gov>

Subject:

.RE: RE: 'existin~ 'pipeline haiai':d evaluation write'"upfor IPEC allegation Folks,.

'.Some minor edits"-as*discussed between Gletm, Rao, and I.today. Please fee! free to make any .editorial edits

,as. yqu ~~e fjt

Regards, Mike McCoppin, MBA~ PMP Branch Chief,. Radiation Protection &

Acciqent Coosequences (RPAC)*

      • t@a>e Q!YISl_Dtif PV SITE *Sid"'~ -"~Q f;N~~~[)~M¢1!-1TA_I;. .~ALY.$1s*

Qffjce"Of N.ewR~a,~tpr~_. . *-

Odite.d. States Nµc1~*~r R~Qi.Jlatory Qoo-m:ii?$ion.

(

Mail Stop: T7-FOS Office: T7-F18 ii' Ph: . 301.415.6533 Cell: ltbxsr I Si FAX: 301.415.5399 Email: micha~l.mccoppin@nrc.gov From: Mccoppin, Michael Sent: Tuesday, December 01, 2015 2:55 PM To: Tammara, Seshagiri <Sesha_giri.Tammara@nrt.gov>; Dentel, Glenn <Glenn.Dentel@nrc.gov>; Pickett, Douglas

<Douglas.Pickett@nrc.gov>

Cc: Hollcraft, Zachary <Zacharv.Hollcraft@nrc.gov>

Subject:

RE: existing pipeline hazard evaluation write-up for IPEC allegation Importance: High Rao .... my edits are im;:_luded.

Thanks, Mike McCoppin, MBA_, PMP Branch Chief, Radiation Prote~tion &

Accident Consequences {RPAC) ll'lPAf~e@

OIVtSION OF Sl,.E SAF'£1'Y.~NO. E.NV-RDNM£NTAL ANALYSU!S Office of New Reactors.

United States Nuclear R~gul~tory Commission

!
Mail Stop: T7:.F03 Office: T7-F18 tr Ph: 301.415.6533

. Cell: ltblt5l I'

,ai FAX: 301.415.5399

-'C! Email: michael,m9coppin@_n.rc_.gov 2

...._....., ....____........_________ -"'------~---------~---

3

.El khiamy.; Sar:ah.

From: Newman, Garrett Sent_: T1.Jesday, Aumist :ts, 2ois:1o::i9 AM To: Krohn, Paul; RlALLEGATION RESOURCE

(:c: L.:()rson, .8.aym0 nd; SuQ¢r, G~egory; Br~n:d, J_ayier; Burritt, Arthl:J_r, Setter; Th9m!ls; Rich, Sarah RE: SENSITVE ALLEGATION:INFORMATlON - Indian Point Alleg~tion regarding Qld *G.as Pipeline ~ Aqditional Info to ASsisdn Eyaluating :ucensee's RFI. Respons~ .

The ductwo.rk along c6r'ltainment is the plant vent. Its radiation monitor R-27 has flow transmitters located at a platform about halfWay up; ttie sampling skid and detector$ are inside the fan ho1;.1se below. R~27 is u~.e.d for EALs and dose assessment. *

  • From: Krohn, Paul Sent: Monqay, August 24, 2015 5;22 PM To: R1ALLEGATl9N RESOIJRCE Cc: Lorson, Raymond; Suber, Gregory; Brand, Javier; Burritt, Arthur; Setzer, Thomas; Rich, Sarah; Newman, Garrett Subje~t: SENSl]'vE_ALLEGATION INFORMATION - Indian Point Allegation regarding Old Gas Pipeline -Mc!itiooaf Info. to Assist in Evaluating Licensee.'s RFI Response Nicole anq Jeff, I was om~ite l~s't w.e~k at Indian Poirit for th$ last week ()f Ci CDBI inspection, Javier Brand ancj myselftoo~ ttw
  • opportunity to look at the old IPEC gas plpeline relative to critfcal structures at IP3. I am at HQs on Monday but Will provide a simplified*sket9h of ~orn~ of the el~vation differences for the allegation file. When I return on.

Tuesday, 8/~:s~

We shouJd us~ lhi~ input in evaluciting the adeqt,1aqy of Enfergy's. respons~ to oor RFL .!terns to consider:

  • IP3 EOG exhaus't damper actualors for .all :3 EDGs have ~ome exposure to heat ,fl_u_x. The exheiust

.damp.er a.ctuators, however, are 'inside the iouvers so .some aaditi_onal *protection from heat flux may be*

justified. In any case, the licensee. shpµld discuss the exposure. c;>f the IP3 EOG exhaust damper-

  • CiCtua.tors to h,eat f!µ.x.
  • u_njt 3 *has som~ ciuc~ing ori, U1e $~e.dor of primary contairirn~.nt It {Uns frqm the ba~e. of c9ntainn1eht to the apex. Not sure what is inside. It couid be primary containment vent controls, rad instrumentation, etc. IPEC should address the contents of the d*ucting for any safety-related. EOP, PAR, or post-acciderit fu_nctlons. .
  • Unit 3 main p9~er output line$. (an 3 pt\a$!3S) will be exposed to the tie_at ffµx~ IPEG should eva!~at!3 if this affects the current carrying capacity of ttie power: transmission lines (i.e., affects.*ampadty). If this is the case,, the potential to-trip Unit 3 on overcurr~nt or some at.her protective.electrical:furiction should.

be evaJ1Jated.

  • Impact on s_ecurity fen*ce detection eaLiiomentshoUld be evaluated.
  • . *the Warehouse is withiif-lOO teef t>f old gas pipeline. eo-r1tents ofwarehouse should be evaluated

_relafiVe to {h~ ~bility qf l,ir)ii ~Jo* get to .~ate. s.htJfd9wr:i. N~m~ly, does th~ ware.hoL1~e COIJt~in any eqi:iipn'ient (hoses, chargers, .etc.) that Ip3* .needs to g~t to Safe shutdown? If the warehouse does GOl"1t~in such equiprnen(H will likely b.e. lpsf d.u[ing an pld pipeli_ne qpnfiagration, ev~nt 1

    • Fi_r~fdiesel building (which is ci.ng~r blopk:*GQnsfrocfipn}anq {wg fire tan~s arer expqsed to heat _

flux. These tfre structures are iocated neat the_ 'Unit 3* RWst. Effect ofslte;s firefighting capabflity snoµld be evaluf;lte9. '

Rega:rdirig the Unit 3 RWST level instruments, these:instruments have a: safety:..related function during a LOCA to,t:1elp operations tr~n~ition f~om th_e i_njection to _the :recin;:ul.ation phase of an a~cid.ent (m~m.ial act\ons ~t IP3)~ It appears that the RWST level instruments_ are shielded by ..;5 feet of an adjpcent concrete structure

  • trom direc_t line..:of-sight, heat f!ux from the point of origin of the gas pipeline (i.e., the adjacent c_oncrete builQin_g's roof is about 5 feet higher than tbe RWST l~vei instn,.1me11ts).

Howev.er, wh~t is uncertain is the 'height of the gas flame (like 8' center of gr~vity concept) and if this allows more of a dfrect h*eat _flux on the RWST level instruments (see drawing}. Also; the ievel instrument enclosure Is.

rotated about 30 degrees off from a direct heat flux azimuth.

Again, the purpose of this email to file is to ehsure we get a quality RFI response from IPEC. Please let Javier

.or mysel_f know if you h~ve .any qu13stions. -

Paul

.i

Elkhiamy, Sarah From: LORSON, RAYMOND K Sent Wednesday, June 08, 2016 12:48 PM To: HAAGENSEN, BRIAN C Cc: LEW~ DAVID C; DENTEL, GLENN T; Pickett, Douglas V; NEWMAN, GARRETI A; RIC:H, SARAH C Subject Re: Pis call me ASAP I am not aware of any inspection or analysis where we looke at survivability of the flex building g. May be addressed in our upcoming see on this tand subject to future inspection From: Haagensen, Brian Sent: Wednesday, June 8, 2016 11:23:45 AM To: Haagensen, Brian Cc: Lew, David; Dentel, Glenn; Lorson, Raymond; Pickett, Douglas; Newman, Garrett; Rich, Sarah

Subject:

RE: Pis call me ASAP I just spoke with Brandon Pinson and Joe Schoppy and they do not recall any insp-ection activity or other analysis that looked at the impact of a gas explosion on the Flex Equipment Storage Building.

I have reached out to Entergy to get their input on this question.

If you have any other information relevant to this question please get this to Dave Lew ASAP. He needs this information (if possible) prior to the AAM this evening.

The question was:

'If a gas pipeline (old pipeline or new pipeline) explosion occurred, would the Flex Equipment Building survive the event?'

Brian From: Haagensen, Brian Sent: Wednesday, June 08, 2016 11:09 AM To: Floyd, Niklas <Niklas.Floyd@nrc.gov>

Subject:

FW: Pis call me ASAP

Nik, Please call me ASAP regarding the email below.

From: Haagensen, Brian Sent: Wednesday, June 08; 2016 11:01 AM To: Schoppy, Joseph <Joseph.Schoppy@nrc.gov>

Subject:

Pis call me ASAP

Joe, 1

During the morning Welcome ses*sioh at IPEC, Dave Lew*had c:fuestions regarding an inspection he said you

.did on the impact of a gas pipeline explosion on the IPEC Flex Equipment Storage Builciing. Please call me ASAP tooay if you hav~ a moment.

Dave stated that somebody (he thought it was you) had looked _at the analysis for the pipeline explo!)ion and determined that the Flex Building would not survive the explosion. He could not recall if this was ah explosion from the n~w line - the old line or both.

Brian c. Haagensen Senior Resident Inspector Indian Point Energy Center

.L.914) 739-9360 (OfficP.)

j<bJ(6J j(ceu, .

2

--** ** H ~.: > * *-. ** * * ****

Elkhiamy, Sarah From: HAAGENSEN, BRIAN C Sent: Monday, June 06, 2016 12:46 PM To: RICH, SARAH C; NEWMAN, GARRED A

Subject:

FW: Latest Revision of Slides for the Indian Point Webinar Attachments: IndianPointMediaBriefing 6-6-2016_Rev3.pptx FYI From: Floyd, Niklas Sent: Monday, June 06, 2016 11:26 AM To: Lew, David <David.Lew@nrc.gov>; Sheehan, Neil <Neil.Sheehan@nrc.gov>; Screnci, Diane <Diane.Screnci@nrc.gov>;

Klukan, Brett <Brett.Klukan@nrc.gov>; Dentel, Glenn <Glenn.Dentel@nrc.gov>; Gray, Mel <Mel.Gray@nrc.gov>;

McHale, John <John.McHale@nrc.gov>; McCoppin, Michael <Michael.McCoppin@nrc.gov>; Noggle, James

<James.Noggle@nrc.gov>; Lorson, Raymond <Raymond.Lorson@nrc.gov>

Cc: Tifft, Doug <Doug.Tifft@nrc.gov>; McNamara, Nancy <Nancy.McNamara@nrc.gov>; Haagensen, Brian

<Brian.Haagensen@nrc.gov>

Subject:

Latest Revision of Slides for the Indian Point Webinar Attached is Revision 3 (most recent version), which includes comments from Dave and Jack.

If you have any other minor changes to make, then please email Neil or myself as soon as possible, so that we can incorporate them into the presentation before the webinar.

Thank you, Niklas Floyd Reactor Inspector Division of Reactor Safety USNRC Region I (610) 337-5282

Media Briefing on Recent Issues at Indian Point Nuclear Plant i f

(.

l f

'\

I t

i i

U.S. Nuclear Regulatory Commission June 6, 2016 1

Reactor Radiation Safeguards Safety Safety T T Initiating Occupational Public Mitigating Bauier Emergency Radiation Events Radiation Systems Integrity Preparedness Safety Safety Performance Indicators Unpl.*nn ~d Sc ram s(W)

. L;st Modif1~d: April 24, 2016

NRC PARTICIPANTS David Lew, NRG Region I Deputy Administrator Neil Sheehan, NRC Public Affairs Officer, Region I Jack McHale, Chief of the Vessels & Internals Integrity Branch, NRC's Office i.

I of Nuclear Reactor Regulation

'I r

I t

' Jim Noggle, Branch Chief in the Region I Division of Reactor Safety I I responsible for radiological safety inspections Mike McCoppin, Chief of the Radiation Protection and Accident Consequences Branch in NRC's Office of New Reactors 3

Degradation of Baffle-former Bolts Baffle-Former Assembly Bolts CORE BARREL FO-R~~~

CORE BARREL TO FORMER BOLT BAFFLE TO FORMER BOLT (LONG & SHORT)

CORNER EDGE BRACKET BAFFLE TO FORMER BOLT EP121 I :..-*'  ::**

4

Degradation of Bolts (cont'd.)

Vessel Head Upper Support Plate Upper Support Column Hold Down Sprinc j Control Rod Guide Tube i

Outlet Nozzle f

i Upper Core Plate Core Barrel i

\ Thermal Shield I

lower Core Plate Pressure Venel

.-*-:- *7*~--* ~ -~";~~** ... "'*1

  • Former Plate I Lower Support Column Body Bottom*mounted Instrumentation Lower Core Support Plate 5

Degradation of Bolts (cont'd.)

REA CT OR CO RE BAFFLE BOLTS l'ORM ER PLATE LOWER CORE P LA1"E 6

Degradation of Bolts (cont'd.)

  • . Baffle High Fluence Edge Seams/Edge Bolts i

}

~~1 1 *" L*

..i t' .,, *. I.

23 E,-,c;;, ~:! . *l:;tLI' "

7

Summary of Bolt Degradation

~ The degraded bolts were identified through required inspections.

~Unit 2 is safe to restart based on bolt replacements and supporting analyses.

~There are no immediate safety concerns with the current operation of Unit 3.

8

Indian Point Groundwater Contamination 9

Indian Point Groundwater Contamination (Cont'd.)

10

Indian Point Groundwater Contamination (Cont'd.)

~

I *l l *; -~Jl

~"t:: rfv~t' Jlt l"fl rti -c~arf~l,at pt t) i~ :::. :>

,-c-...,;.Nh*:' fC'J" ~f:tttb1:-:ir"" l .. 11; !~' "f -'1~)

11.., g~.r, ~oe-~ fi:Jtl" .2tQ1., 'ff'e '3S;*f.

1md r1y.>lolir,,. mdo w*P> rl~ r"";1-"!ll<i

' /

,y.:.tti- t;~f\tain4;'1*:f *~r in \U~ ' *f1101W'JlhQ ~ lit:**

  • ' t) "f f~ l lf\!1t1*tif.al ~~ <'! t.~.,,.,

.--~l -- .

11

~ From ~he E~A ~a?t she~t ~n tritium: .~#a~<t\

As with all 1on1z1ng rad1at1on, l ~ ~')

exposure to tritium increases the "1,.4t , ,.,o~c:;!J risk of developing cancer. However, because it emits very low energy radiation and leaves the body relatively quickly, for a given amount of activity ingested, tritium is one of the least dangerous radionuclides."

12

NRC Regulations on liquid

. radioactive releases

~ Nuclear power plant liquid and gaseous releases to the environment are required to be planned, monitored and documented

~ NRC regulations (10 CFR Part 20 and 10 CFR

} Part 50) place limits on these releases to ensure safety standards are being met, such as NRC I

I ~

ALARA limits and EPA drinking-water standards On an annual basis, NRC guidelines require that I

A the release of radioactive liquids from a nuclear power plant not result in a radiation dose of greater than 3 millirems to any individual in an unrestricted area 13

Indian Point Groundwater Contamination Summary

~ No health and safety significance

~ Promptly detected and investigated

~ Building drains and pumping system improvements are underway 14

Installation of Pipeline Spectra EnergY)

}~~ ?'

Partne rs Cro111wctfl C/S

\:__,"i' I ~

O.ford C/ S

V v c r .* 1:.,:,~ . ;;: n

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ir~r

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[ ~~.~.!.~:~~ (~!-.~~

SoU1hHtt (/S Stonv Point C/S ....,

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..... \ \\

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'\ i ', West Roxb\iry late1al

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Z... 0. "" 3&" l v..;p SoU1 h~a st t o MLV-19

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' ..> -.'t;* ~,... \ 4 .S r1:i . & R 26"w/ .\2"

  • f _ _ _ _ __\ 11 ... lu:J.-, Rt f>.l tUJ (0 1 *1 * *:**;)

_i_::::::===:::::::::::-_..;....--~

l rw w ' l" " ! ("f ~. ! ,1f °' , ~

)4 "'1!' '.N <: .1 !"(1 -01 r !'q .1.r(' ""l!'l~*f ~.J~i~n<

Stony Poin t to MP 9 1.2 I ~ 7 ' *r1i l&R 2f. "w i47 "

AIM Project - 342,000 Dth/d I

I r: cl .;<!>11oe\\10. J T t1 .r -iu:lVJ "l 'bvl'I rlDD~

t Fac.ilities OiagrJm Rev: 4-March-2014 15

Thresholds for Damage

..  : .~

1 psi Glass shatters 2-6 psi Serious structural damage to houses 6-9 psi Severe damage to reinforced concrete structures 10 psi Destruction of Buildings

  • No safety-related structure necessary to safely shutdown IPEC exposed to >1 psi
Thermaf Heat Flux*(kWJm2) 2 Pain within 60 sec 5 Tolerable to escaping personnel 12.6 Plastic melts 31.5 Building Damage
  • Max heat flux at SOCA boundary found to be about 1/2 of that which melts plastic*

Installation of Pipeline (Cont'd.)

t 1

i1 i

17

Installation of Pipeline (Cont'd.)

, I

,f

. I J

I 18

Summary of Pipeline Installation

~ Independent and diverse analysis (NRC, Entergy, DOT) demonstrate no safety impacts.

~Actual explosions confirmed NRC analysis l f is conservative.

~ Plant equipment needed to shutdown

'I I

I

\

l would remain available during a pipeline explosion.

19

Q(;

Additional information/questions

~ Contact Neil Sheehan, NRC Public Affairs Officer, at 610-337-5331 or via e-mail at Neil.Sheehan@NRC.GOV t

1 I

I

'i i

i l.

.! I 21

Elkhiamy, Sarah From: Pinson, Brandon Sent Monday, October 19, 2015 8:46 AM To: Pickett, Douglas

Subject:

    • Sensitive Allegations Material** Rl-2015-A~0074 RFI response Attachments: RFI response Rl-2015-A-0074.pdf
Doug, See attached for the RFI response regarding the IP3 gas pipelines.

Brandon Pinson RI, DRP, Br;md1 '.2 (610)-337-5390 1

  • 0 '< IO OMO o ** 0 ? ( > M _ . . ....,. . . ~ . . . . . . . . . . " " ~ ooO 0 *O I<

Elkhiamy, Sarah From: Pickett, Douglas V Sent: Thursday, December 03, 2015 2:10 PM To: DENTEL, GLENN T; Draxton, Mark S; Pinson, Brandon B; Schussler, Jason E Cc: HAA(;ENSEN, BRIAN C; NEWMAN, GARRETT A; RICH, SARAH C

Subject:

Indian Point Gas Pipeline Allegation Support Attachments: Indian Pt-Rao's Allegation_analysis_writeup (w corrections 12-1-15).doc Folk~ -

Attached is the writeup prepared by Rao in support of the Indian Point existing gas pipeline allegation. It was reviewed by both Mike McCoppin and Zachary Hollcraft. Please let me know whether this will be sufficient fQr your response. FYI - Rao will bej(b)(GJ jtor 5 weeks starting Tuesday, December 8.

Doug l

Confirmatcuy Analysis of Allegat*on Concern Evaluation Of Existing Pipelines Rupture Impact At Indian Point Energf C~ntet (IP,ECJ INTRODUCTION The licensee, Entergy, provided a response to NRC Request for Information (Ri:-2015-A-'0074).

As a part bf the staff's review and evaluation of the response and associated attachment and

  • enclosure, the NRC staff *performed independent confirmatory calculations to ascertain the reasonability of approach, assumptions and methodology that Entergy used in their evaluation ofcoilsequertces for the consideration of resolving the concerns raised in this RI. The staff's confirmatory calculations include the determination ofthe distance to 1 psi overpressure due to potential release of natural gas and explosion at the sour~e of re.lease, due to vapor cloud explosion;and c!istanc~ to potential heat flux of 12.6 kw/m 2 due to release of gas as a jet fire.

SUMMARY

OF EVALUATION Entergy evalu~ted the potential hazard.s* to saJety-related s_tructures, systems, and component~

(SSCs) and also SSCs. ir:nport~nt to ~afety (SSC. iTS) using the SREEZE c.omputer rnodelwith rea.sonable approach and ass:umptions. The staff performed independent confirmatory

  • calculations with conservative assumptions and rcationale u*slng RG 1.91 methodology for source explosion and also used the ALOHA computer model for Vapor plume explosion, "the staff used the ALOHA model to perform the confirmatory calculations to determine:
1) Distance to 1 psi overpressu-re due to. release and potential at source (at pipe rupture),
2) Distance to 1 psioverpressure due to delayed vapor cloud explosion,
3) Distance to heat flux of *12.6 kw/m 2 from natural gas release as jet fii'e.

The staffs independent confirmatory calculation results are based on highly conservative assumption ahd rationale by modeling an instantaneous maximum one minute gas release rate

.for the potential explosion at the source. The nlpture ofthe pipeline is assumed to -be located at the closest SSC. Based on this, the staff :eoncludes that.1 psi overpressure is extended to a distance of (bJ! 7l(F) which ooilld potentially impact the safety*related sscs and also the sscs important to safety. Since the pipeline is buried underground, a more reasonable average release rate, as calculated using ALOHA to determine total amount of gas released over the time eriod to 'empty the pipeline, results .in a recalculated distance to :1 psi. overpressure of (b)(7J(FJ !b In general, the review criterion of 1 psi overpressure provides a margin failure Of safety related SSCs~. The safety-related SSCs ar$ designed to withstand .overpress1,1re of 3 psi or more without lo~~ of their-safety functio_n,s. In 9rder tq es1imate the distance to potential3 pi;;i.

overpress.l,lre, using the f?ame ~verage releas.e rat!; 'th~ qistance to 3 psi overpressure is calc~lateg tQ -~~<blC7 l<F> I

  • The staffs analysis of the; distance to bverpressil~e of 1 psi due to a delayed va'por cloud

. SE;NSFfl'Jg SE$i:iRi=rY RE;LATi;I:> iNFORNiAi=1.eu*~

  • -2:-

explosion ~ssumed c0ngestio*n in the ar:ea *of release. The resuits extend the 1 psi overpressure to impact some satetY-"related SSCs. and SSCs i'mportant to safety. However, the ov~rpressure did not exceed 3 psi ~t any distance {to any SSCs). A sensitivity analysis, which, tnore realistically, assumed no congestion in the area, resulted in no 1 psi overpressure at any distance due to vapor cloud explosion ..

Using the ALOHA model, the staff calculated that the thermal radiation level of 12.6 kW/m 2 would extend to a distance 6~(bl<7><f'J I Based on the results of th'e confirmatory analysis, the staff concludes that the safety related SSCs, as Well as SSCs important tci safefy,. would potentially be exposed to 1 psj overpressL1re, and a few SS9s. important to safety rnl:IY be expo~~d to heat flu~.of 12.q kw(rn 2 , whict:l is c9mparable to the liqensee's con.clusions.

TECHNICAL EVALUATION The st13ff perfortn.ed an indepepdent con.finriatory ~nalysis base.cl on ttie. rup.tµre of fhe exl'~ting 30-if'lch natur~I g~~ pipeline, which_ ~onsists of abotJt 6 miles of pipeline between isolation V{:Jl\les. Th~ analysis ass.urned that a rupture qf th~ na.tur~I gas pipeline may result in an unconfined explpslon or jet flame at the*source or in a del~yed vapor-cloud explosion downwind.

For the assessment of an unconfined exp.loslon, the staff used RG 1.91 methodology to

  • calcuiatetlie minimum safe distal')ye d_Ue to the source explosion. For the Jet flame and c:JeJayed vapor clou.d explo.siort, the ~taff .used the Al-OHA chemical reJeas_e modeling computer

'.Co.de to determine the hazard impact dista:nces to compare with the ~actual distances .to S.SCs relatect to s.afety or SSC iTS, in order to as!3e.s.s the impact potential. The ALOHA code is used

.to cai.culate_the amount of meth~lne relea*sed for the scenario conside*reo, *using: conservative meteorological cC>nditions Ccfnsisting of ail. assu*med wind :Spe.ed of 1 m/s, F stability, and 25.

deg. C. arr\bient temperature, Cloud*toVer't>f0.5 and relativ~ humidity ,of 50%. Open countj gr.ounq roughness conditions modeling .assumptions were chosen as being appr:opriate 'fodhe iocatlon. .. * -- -

E~plQsjc;m The ALOHA cbde model for' an expiosion scenario conservatiV.ely estimated the gas relea*se from a pipe rupture attlie clos.est iocation to an SSC by consid~ring the lenQth of pip*enne to be 6 miles, witn the rupture creating a hole equivalent to the diameter of.the pipe (30 inches diameter) at a maximum. operating pressure of 674 psia. The calculation results.give a maximum sustained methane release rate and estimated total release amount over time (to

~lq.llate average release rate), bas ~m tl:l~ clo$ure of the isglation valves followihg the nJpt1..1re,

~ss_urning that the. entire volume of gas _in t'1e pipe.line section !Jetwe.eri .the closed va_lves. i~

bein~ rele9seq.

Con*serv~tivefy as-surning.lhe.rna~im_um one minute relea$e rate; and__determining the_ TNT

.equ(valent a:m6unt wi.th -~ ylE11d factor ot0.05 (WTNT) (~quation given belbw), the* minimum

- SEN81l'n/E 'SESl:IRITY RELA+EB !Nf'3RMl."FION

____.....______________________ _....__________ ....__"'--.;___;,~'------ ..---* *****- ..... -**- ...... .

  • -'>._:-****-.--***:********-*** .* ..._., ... ::..***-**-**:~* ~** . . **:** *.....

s*ENSl'Fi1iE $E6.t:l~i;n' F(EL4EB INFOR.Nhf<Fli:)N safei: distance (d) to 1 *psi overpressure* ls calculated by using RG 1.91 rnethodologf as. foli.ows:

WTNT= (Mf

  • DHC
  • Y)/4SOO where WTNT= TNT equivalent Mass;* kg Mf = M~ss of vapor, kg DHC = Heat of co'mbustion, kj/kg (50030)

Y = Vie.Id Factor (0.05) ano d= 45 * (w) 113 where d= minimum safe distance (ft.) to 1 psi overpres.sure w= TNT equivalent mass in pounds The staff calculated that th*e safety related ~SCs, as well as the SSCs important to safety, lo~ted.

beyond a minimum safe distance b~ <t>J<7J<Fl will not be exp_osed to an overpre$sure of 1 psi. As th.e pipeline.is buried underground, the use b maxilT]um instantane.ous one minute gas. release rate may be overly con*servative. Therefore, *an average rate ofg*as release based on total amount of gas released over the time period to empty the pipeline, as calculated using ALOHA is*

assumed as a reasonable value. Usin this average gas release rate, the distance to 1 psi overpressure was re-calculated to.be (bJ(7l<FJ Generally the safety-related SSCs are designed to wi~hstand overpressure of 3 psi or more. lri order to estimate the distance to potential 3 psi overpr~ssure, usin the same average release rate; the dist~nce to 3 psi qverpressure is calculatE;d *to be (b)(?J(FJ The staff;s analysis of the d.i.starwe to not exceeq ap o.verpressur.e 9f 1 psi due to delayed vapor cloud expli:>"sion C!Ssum.e"d congestion in the area.of rele;;ise, wt-ilch would represent .dense forest or l:>uildings which enha.nce gas accumu!ati9n due tp pot~ntial corifineme.nt The re_suJts extend "the. 1 psi overpressure distance "to impact some safety-related_ SSCs and SSC's imp9rt9nt to safety. However, the overpressure di~ _not exc;eed *3' psi.at any distanGe (f9r any $SCs), These results are cornparable* tp fhaf "Of the licensee's analysis results; A sensitivity analysis, whiGh m.ore reaJi$ti~lly assumed no cqngestipn in the area, res!Jlfed in no 1 psi overpressu~e aj any distance:due to vapor Cloud explosion, Jet Fire*

The ALOHA code for jet fire scenarios was run conservatjveiy for the pipe rupture at a loGC!Jion Closest to ah SSC by corisiderlhg the.length of the pipeline be.tween iso.latlon vaives to be 6 miles, with rupture*creating,a hole eqUivalent to the diameter of the pipe (30 inches* diameter) at a maxim.um operating_ pressure of 674 psia. Methane is assumed to be released from the ruptljred pipe .as a.flam111al:>le ga$ and is assumed to be burning. The ALOHA calculatkm r~sulfed in. a mqxim_urn b1,m1 rate. as well as an, estiinafed t_otal amc;>u,nt burned .over time, baseq

SENSITIVE- SECURITY RELATED INFORMATION

-4" on closure of the isolation valve*s following the rupture. Based on the- assumption that the entire volume of _gas. in the pipeline section between the closed valves is being released, the distances to thermal radiation levels of 31.5 kW/m 2 , 12.6 kW/m 2, and 5.Q kW/m 2 calculated by ALO.HA are

  • 1<t>l<7J(FJ Irespectively. A few safety related SSCs anq SSCs important to safety may be impacted. Thes_e results are consistent with the licensee's analysis results.

CONCLUSION Based on the results of the staff's independenrconfirmatory f:malysis, the staff concludes that the safety-related SSCsas wen as SSCs important to safety would potentially be exposed to 1 psi overpressure, and a few SSCs important to. safety may be exposed to heat flux of 12.() kw/m 2, which is GQmparable to the licensee's conclusion. Although the licensee's pip~line hazard impact evaluation used different models, ;:issumptions, and methodqlogy than the staff used in its independent confirmatory analyses, the staff's results and conclusions are consistent with the licensee's results and conclusions. Therefore, the staff considers the licensee's haz~rd impact eval~ation to b~ reasonable and acceptable.

SEN&ll'l\'li i&e~Rl:rY Aib.Os:r&Q INFQR.MATION

Tammara, Seshagiri From: Tammara, ~eshagiri Sent: Thursday, December 03, 2015 3:22 PM To: McCoppin, Michael

Subject:

RE: RE: existing pipeline hazard evaluation write-up for IPEC allegation Attachments: Indian Pt-Rao's Allegation_analysis_writeup (w corrections 12-1-15) (00000002).docx Mike:

I have addressed the comments and attached herewith the write-up for your review and for further transmittal.

Thanks, Rao From: Mccoppin, Michael Sent: Tuesday, December 01, 2015 2:55 PM To: Tammara, Seshagiri <Seshagiri.Tammara@nrc.gov>; Dentel, Glenn <Glenn.Dentel@nrc.gov>; Pickett, Douglas

<Douglas.Pickett@nrc.gov>

Cc: Hollcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

RE: existing pipeline hazard evaluation write-up for IPEC allegation Importance: High Rao ... my eciits are included.

Thanks, Mike l\*kCoppin. MBA, PMP Branch Chief, Radiation Protection &

Accident Consequences (RPAC)

Office of New Reactors United States Nuclear Regulatory Commission

.:..!.: Mail Stop: T7-F03 Office: T7-F18 2 Ph: 301.415.6533 Cell: j(_b)(6) I

.~, FAX: 301.415.5399

-lj Email: michael.mccoppin@nrc.gov 1

av nlcation in error, please notify me Imm v return e-mail and delete the or of it from your 2

Si:MHTiV,1!-S~et:IRfR' RELATES INFQRMilt:"flON Confirmatory Analysis of Allegation Concern Evaluation Of Existing Pipelines Rupture Impact At Indian Point Energy Center (IPEC)

INTRODUCTION fhe licensee, Er:itergy, p_rovided a re~ponse to NR_C Request for Information (Rl-2015-A-0074).

As a part of the staff's review and evaluation of the response and associated !3tta_chment and enclosure, the NRC staff performed independent co_nfirmatory calculations to ascertain the reasonability of approach, assumptions and methodofo~y that Entergy used in their evaluation of consequences for the consideration of resolving the concerns raised in this RI. The staffs confirmatory calculations include the determination of-the distance to 1 psi overpressure due to potential release of natural gas and explosion at the source of release, due to vapor cloud explosion, and distance to potential heat flux of 12.6 kw/m 2 due to r~lease of gas as a jet fire.

SUMMARY

OF EVALUATION Entergy evaluEjted the potential hazards to safety-related structures; systems, and components (SSCs) and als_o SS-Cs important to safety (SSC IT$) using tne BREEZE c_omputer mod~I with reasona,ble appro~ch and ~ssumptions, Th~ st_aff p~rformed [ndependent confirmatory calculations with Col)servafive assumptions and ra!ionale lJsing RG 1.91 methodology for sol!rce explosion and also used the ALOHA computer model for vapor plume explo$ion. The staff used the ALOHA model. to perform the_ confirmatory calculations to determine:

1) Distance to 1 psi overpressure due to release and potential at source (at pipe rupture),
2) Distance to 1 psi overpressure due to delayed Vapor cloud explosion,
3) Distance to heat flux of.-12.6 kw/m2 from natural gas release as jet fire.

The stcaff's independent confirmatory calculation results are based on highly conservative 8$SUmpt_ion ai'ld r~tio!lale .by modeling ga~ release rate for the potential explosion at the source.

The rupture of the pipeline is assumec:t to be located at the closest SSC. Since the pipeline is buriecj undergroum::l, an average release rate, as calculated using ALOHA to determine .total amount of gas released over the time period to em-pty the pipeline; results in a calculated distanGB to 1 psi overpressure of (b)(?)(F) In general," the review criterion of 1 psi overpressure proviqes a margin t~ failure of sa e y re a ed SSCs. The safety-related SSCs are designed to withstand qverp_ressure.of 3 p~i or more without loss of their safety functions. In order to estimate the djstanc_e to potential 3 psi overpressure -using the same average release rate, the distance to 3 psi ov~rpressure is calculated to be (b)(?)(FJ The staff's analysjs of tbe distance to overpressure of 1 p§i dµe to. a c:telayed vapor cloud explosion assumed congestion* in the area of release. The resuJts extend the 1 psi overpressure to lm*p_act some safety-related S$Cs ~nd S$Qs .frnportant to safety. However, the overpressure did not excee_d 3 psi at any distance (to any SSC,s). A sensitivity arialysi~. which,

~EN$l'fl'1rE = SEOl:lfllTY RELATEB mroRMAfl9H

SENSITl\1E SESl:JRl=rY RELATEB INF8.RMMION more realistically, assumed no congestion in the area, resulted in no 1 psi overpressure at any distance due to vapor cloud explosion.

Using the ALOHA model, the staff calculated that the thermal radiation level of 12.6 kW/m 2 would extend to a distance o~(b)(?)(F) I Based. on the results. of t_he. c;onfirmatory ;:m,aly5is, t_he staff conc;ludes that the safety related SSCs, as well as S$Cs important to safety, would potentially be exposed ~o 1 psi overpressure, and a few SSCs import~nt to safety may be exposed to heat flux of 12;6 kw/m 2 , which is comp_arable to the Jicensee's conclusio.ris.

TECHNICAL EVALUATION The staff performed an *independent confirmatory analysis based on the rupture of the existing 30-inch natural gas pipeline; wh!ch consists of about 6 miles of pipeline between isolation v~lves. The analysis assumed that a rupture of the natural gas pipeline may result in an unconfined explosion or jet flame at the source or in a delayed vapor cloud explosion downwind.

for ttie assessment of an unconfined e?Cplosion, the staff used RG 1.91 methodology to palculate the minimum safe dtstance due to the source explosion. For the jet flame and qelayed vapor cloug e);(plosion, the staff used the ALOHA ~herniG~I release modeling computer

_co_de to de.termine- the ~azard impact di$tances to compare. with the aptual distances to. S$.Cs related to safety or SSC IT$, in order to a_ssess the imp_ac;t potenti!al. The ALOHA code is used.

to calculate the amount of methane. released for the scenari~ considered, u_sing conservative meteorolog.ical c.onditioris consisting of an assumed wind speed of 1 mis in the direction of SSC, F stability, and 25 deg. c ambient temperature, cloud cover of 0.5 and relative humidity of 50%.

Open country ground roughn-ess conditions modeling assumptions Were chosen as being appropriate for the location.

Explosion The ,A.LOHA coqe mqd~I for an exp!os!on scenario conservatively estimated the gas release from ~ pipe rupture at the closest location to ah SSC by considering the.leng~h of pipeline to be E> n,iiles, with the rupture creating a hole equivalent to the dia*meter of the pipe (30 inches*

diarrieter) at a maximlJm operating pressure of* 674 psia. The calculation results give an estimated total methane release amount over time (to ealculate average release rate) based on the clos.ure ofthe isol~ticm valves following the rupture; assuming that the entire volume cif gas in the pipeline sect_ion between the closed valves is being released.

Assuming the aver~ge relei?se rate, and determining lhe TNT equivalent amount with a yield factor of.0,.05 (WT!"JT) (equation given below}, the minimum safe dJstance (d} to 1 psi overpressure is calculated by using RG 1.91 methodQlogy as follows:

WTNT= (Mf

  • OHC
  • Y)i450Q 8Ef~Sl'fl\'t! :eee~Rl=rY RELATEB iNF9~MATIEUJ

SENSITPIE SEOl:JRln' RELATt:B INFORMATION where WTNT= TNT equivalent Mass, kg Mf = Mass of vapor, kg

=

DHC Heat of combustion, kj/kg (50030)

Y =Yield Factor (0.05) and d= 45 .,. (w) 113 where d= minimum safe distance (ft.) to 1 psi overpressure w= TNT equivalent mass in pounds As the pipeline is buried underground, an average rat.e of gas release based on total amount of gas released over the time period to empty the pipeline, as calculated using ALOHA is assumed. Using this average gas release rate, the distance to 1 psi overpressure was calculated to be l(b)(?)(F) !Generally the safety-related SSCs are designed to withstand overpressure of 3 psi or more. In order to estimate the distance to potential 3 psi overpressure, usin the same av~rage release rate, the distance to 3 psi overpressure is calculated to be (b)(7)(F)

The staff's analysis of the distance to not exceed an overpressure of 1 psi due to delayed vapor cloud explosion assumed congestion in the area of release, which would represent dense forest or buildings which enhance gas accumulation due to potential confinement. The results extend the 1 psi overpressure distance to impact some safety-related SSCs and SSCs important to safety. However, the overpressure did not exceed 3 psi at any distance (for any SSCs). These results are comparable to that of the licensee's analysis results. A sensitivity analysis, which more realistically assumed no congestion in the area, resulted in no 1 psi overpressure at any distance due to vapor cloud explosion.

Jet Fire The ALOHA ccx;le for jet fire s.cenari<;>s was run conservatively for the pipe rupture at a location closest to an SSC by considering the length of the pipeline between isolation v;:1lves to be 6 miles, with rupture creating a ho.le equivalent to the diameter of the pipe (30 inches diameter) at a maximum operating pressure of 674 psia. Methane is assumed to be released from the ruptured pipe as a flammable gas and is assumed to be burning. The ALOHA calculation resulted in a ma~imum burn rate as well as an estimated total amount burned over time, based on closure of the isolation valves following the rupture. B~sed on the assumption that the entire volume of gas in the pipeline section between the closed valves is being released, the distances to thermal ~adiation levels of 31.5 kW/m 2 , 12.6 kW/rri 2, and 5.0 kW/m 2 calculated by ALOHA are l(b)(7)(F) !respectively. A few safety related SSCs and SSCs important to safety may be impacted. These results are consistent with the licensee's analysis results.

CONCLUSION SEN.SITl\1E ~E6l:IRJTV FUib.O,JEiP 1Nli9&1UJATION

~*ENSITiVli &i!G'IRITY ~ib;ATEB INFORMATISH Based on the. re.suits of the staff's independent confirmatory analysis, the staff concludes that the safety-related SSCs as well as SSCs important to safety would potentially be exposed to 1 psi overpressure, and a few SSCs important to safety may be exposed to heat flux of 12.6 kw/m 2 , wflich is comparable to the licensee's conclusion. Although the licensee's pipeline hazard impact evaluation used different models, assumptions, a*nd methodology than the staff used iri its independent confirmatory analyses, the staff's results and conclusions* are consistent with the licensee's results and conclusions. Therefore, the staff considers the licensee's* hazard impact evaluation to be reasonable* and acceptable.

$~14Sll"lvE -$1!!!Ct:JRIT't' Rl!LM'!!> INfOftMNJION

Tammara, Seshagiri From: Tammara, Seshagiri Sent: Friday, December 04, 2015 9:27 AM To: Mccoppin, Michael; Pickett, Douglas; Dentel, Glenn Cc: Hollcraft, Zachary

Subject:

FW: RE: existing pipeline hazard evaluation write-up for IPEC allegation Attachments: Indian Pt-Rao's Allegation_analysis;..Writeup (w corrections 12-3-15) (00000002).docx; IPEC_exisiting_pipelines_impact_writeup_redac.pdf Mike/Doug/Glen:

I am on (b)(6) Mike attached and transmitted the above file yesterday. In case there is a FOIA request, I have identified in yellow/red the potential results that may be redacted, ~md attached that scanned file (.pdf) for your convenience and easy referral.

Thanks.

Rao From: Mccoppin, Michael Sent: Thursday, December 03, 2015 3:54 PM To: Tammara, Seshagiri <Seshagiri.Tammara@nrc.gov>; Dentel, Glenn <Glenn.Dentel@nrc.gov>; Pickett, Douglas

<Douglas.Pickett@nrc.gov>

Cc: Hollcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

RE: RE: existing pipeline hazard evaluation write-up for IPEC allegation

Folks, Some minor edits as discussed between Glenn, Rao, and I today. Please feel free to make any editorial edits as you see fit.

Regards.

Mike McCoppin, MBA, PTYIP Branch Chief, Radiation Protection &

Accident Consequentes (RPAC)

Office of New Reactors United States Nuclear RE;?gulatory Commission 1~!:0 Mail Stop: T7-F03 Office: T7-F18 R Ph: 301.415.6533 Cell: j(b)(6) I

~ FAX: 301.415.5399

~ Email: michael.mccoppin@rirc.gov 1

From: Mccoppin, Michael Sent: Tuesday, December 01, 2015 2:55 PM To: Tammara, Seshagiri <Seshagiri.Tammara@nrc.gov>; Dentel, Glenn <Glenn.Dentel@nrc.gov>; Pickett, Douglas

<Douglas.Pickett@nrc.gov>

tc: Hollcraft, Zachary <Zachary.Hollcraft@nrc.gov>

Subject:

RE: existing pipeline hazard evaluation write-up for IPEC allegation lmporta.nce: High Rao ... my edits are included.

Thanks, Mike McCoppin, MBA, PMP Branch Chief, Radiation Protection &

Accident Consequences (RPAC)

DSEA. I@*@*-o© ' . .

'll>.1P, ' .~:,"

Office of New Reactors United States Nuclear RE;igulatory C9mmission

lJ Mail Stop: T7-F03 Office: T7-F18 2t Ph: 301.415.6533 Cell: '~(b_)(6_)_ _~

i;.,l FAX: 301.415.5399

'1e Email: michael.mccoppin@nrc.gov 2

SE;qSITl'o'! !ECUftlTY RELATED UdFORMATION Confirmatory Analysis of Allegation Concern Evaluation Of E.)(isting Pipelines Rupture Impact At Indian Point Energy Center (IPEel INTRODUCTION The licensee, Entergy, provided a response to NRG Request for Information (Rl-2015-A-0074).

As a part of the staff's review and evaluation of the response and associated attachment and enclosure, the NRC staff performed independent confirmatory calculations to ascertain the reasonability of approach, assumptions and methodology that Entergy used in their evaluation of consequences for the consideration of resolving the concerns r~ised in this RI. The staff's confirmatory calculations include the determination of the distance, to 1 psi overpressure due fO potential release of natural gas and explosion at the source of rele~se, due to vapor cloud explosion, an~ distance to potential heat flux of 12.6 kw/m 2 due to .release of gas as a jet fire.,

SUMMARY

OF EVALUATION Entergy evaluated the potential hazards to safety-related structure::;, systems, and componerf:s (SSCs) and also SSCs important to safety (SSC ITS) using the BREEZE computer model with reasonable approach and assumptions. The staff performed independent confirmatory I

calculations with conservative assumptions and rationale using RG 1.91 methodology for source explosion and also used the ALOHA computer model for vapor p1J.me explosion. The staff used the ALOHA model to perform the confirmatory calculations to dete~mine:

1) Distance to 1 psi overpressure due to release and potential at source (at pipe rupture),
2) Distance to 1 psi overpressure due to delayed vapor cloud explbsion,
3) Distance to heat flux of 12.6 kw/m 2 from natural gas release as Jet fire.

The staff's independent confirmatory calculation results are based .on highly conservative assumption and rationale by modeling the gas release rate for the potential explosion at the source. The rupture of the pipeline is assumed to be located at the closest SSC. Since the pipeline is buried underground, an average release rate, as calcul~ted I using ALOHA to determine total amount of gas released over

  • period to empty the pipeline, results in~

calculated distance to 1 psi overpressure of (bJ(?)(FJ In general, th~ review criterion of 1 psi overpressure provides a margin to failure of sa ety related SSCs. trhe safety-related SSCs ate designed to withstand overpressure of 3 psi or more without loss qf their safety functions. In order to estimate the distance to potential 3 psi overpressure, using the same average releas~

rate, the distance to 3 psi overpressure is calculated to be (bJ(7 J(F) j The staff's analysis of the distance to overpressure of 1 psi due to la delayed vapor cloud explosion assumed congestion in the area of release. The results: extend the 1 psi overpressure to impact some safety-related SSC.s and SSCs impo:rtant to safety. However, t~e overpressure did not exceed 3 psi at any distance (to any SSCs). A sensitivity analysis, whic)l, I

I I

81i~d81Tl'/E SESl:IRITY RELATEB n4i;efUfll<TIOtcJ

SENSi i)vE SECURIT' i\il!!LA"f!f) U4rO~;AlATION mdlre realistically, assumed no congestion in the area, resulted in no 1 psi overpressure at any dis.tance due to vapor cloud exolosion.

Using the ALOHA model, the.staff calculated that the thermal radiation level of 12.6 kW/m 2 wduld extend to a distance ofl(bJ(7)(FJ 1-B~sed on the results of the confirmatory analysis, the staff concludes that the safety related SSCs, as well as SSCs imporitant to safety, would potentially be exposed to 1 psi overpressure, anti a few SSCs important to safety may be exposed to heat flux of 12.6 kw/m 2 , which is comparable to the licensee's conclusions.

racHNICAL EVALUATION Th.le staff performed an indep~ndent confirmatory analysis based on the rupture of the existing 3minch natural gas pipeline, which consists of about 6 miles of pipeline between isolation va1ves. The analysis assume'.d that a rupture of the natural gas pipeline may result in an unponfined explosion or jet fl~me at the source or in a delayed vapor cloud explosion downwind.

Fat the assessment of an un¢onfined explosion, the staff used RG 1.91 methodology to ca(culate the minimum safe distance due to the source explosion. For the jet flame and delayed vapor cloud explosioh, the staff used the ALOHA chemical release modeling computer cof;fe to determine the hazard'. impact distances to compare with the actual distances to SS Cs rell;lted to safety or SSC ITS, in order to assess the impact potential. The ALOHA code is used to calculate the amount of m~thane I released for the scenario considered, using conservative m~teorological conditions consisting of an assumed wind speed of 1 m/s in the direction of the S~C. F stability, 25 deg. C arlibient temperature, cloud cover of 0.5 .and relative humidify of 50P/o. Open country ground r~ughness conditions modeling assumptions were chosen as being appropriate for the location.

Exjplosion Th'.e ALOHA code model for an explosion scenario conservatively estimated the gas release frotn a pipe rupture at the clO$eSt location to an SSC by considering the length of pipeline to be_ti miles, with the rupture creating a hole equivalent to the diameter of the pipe (30 inches di::frneter) at a maximum ope~ating pressure of 674 psia. The calculation results give an es1imated total mefhane relea$e amount over time (to calculate fhe average release rate) based on thA closure of the isolation valves following the rupture, assuming that the entire volume of gas in fhe pipeline section betwee;n the closed valves is being released.

As}>uming the ---

average releaseI rat~.*and determining the TNT equivalent amount with a yield fadtor of..CLOS JWTNT) (equali.b_n given below), the minimum safe distance (d) to 1 psi ov13rpressure is calculated bylusing RG 1.91 methodology as follows:

S 6 NlelliVli 8~CYRITY REbATED !NFORMMION i

SEt*SITl\<<E SEQl::IRl=rY REbA:ri9 ltlFQRMA:rlQH WTNT= (Mf

  • DHC
  • Y)/4500 where WTNT= TNT equivalent Mass, kg Mf = Mass of vapor, kg DHC =Heat of combustion , kj/kg (50030)

Y =Yield Factor 0 05 and d= 45 * (w) 113 where d= minimum safe distance (ft.) to 1 psi overpressure w= TNT equivalent mass in pounds As the pipeline is buried underground, an average rate of gas release based on total amount df gas released over the time period to empty the pipeline , as calculated using ALOHA is assumed. Usin this average gas release rate, the distance to 1 psi overpressure was calculated to be (b)(?XF> Generally the safety-related SSCs are designed to withstand overpressure of 3 psi or more. In order to estimate the distance to potential 3 psi overpre ssur~

usin the same average release rate, the distance to 3 psi overpressure is calculated to be (b)(7XF)

The staff's analysis of the distance to not exceed an overpressure of 1 psi due to delayed vap~r cloud explosion assumed congestion in the area of release, which would represent dense fore6t or buildings which enhance gas accumulation due to potential confinement. The results extenti the 1 psi overpressure distance to impact some safety-related SSCs and SSCs important to safety. However, the overpressure did not exceed 3 psi at any distance (for any SSCs). Thest results are comparable to that of the licensee's analysis results. A sensitivity analysis, which more realistically assumed no congestion in the area , resulted in no 1 psi overpressure at any distance due to vapor cloud explosion.

Jet Fire The ALOHA code for jet fire scenarios was run conservatively for the pipe rupture at a location closest to an SSC by considering the length of the pipeline between isolation valves to be 6 miles, with rupture creating a hole equivalent to the diameter of the pipe (30 inches diameter) cit a maximum operating pressure of 674 psia. Methane is assumed to be released from the ruptured pipe as a flammable gas and is assumed to be burning. The ALOHA calculation resulted in a maximum burn rate as well as an estimated total amount burned over time, based on closure of the isolation valves following the rupture. Based on the assumption that the entioo volume of gas in the pipeline section between the closed valves is being released, the distances to thermal radiation levels of 31 .5 kW/m 2 , 12.6 kW/m 2 , and 5.0 kW/m 2 calculated by ALOHA are k ; XF> Irespectively. A few safety related SSCs and SSCs important to safety ay be impacted These results are consistent with the licensee's analysis results.

SD*Sll l\<<E SEQl::IRl=rY REbA:rEQ INl&QR,.,ATIQN

CbNCLU SION B ed on the results of the staff's independent confirmatory analysis, the staff concludes that t* safety-related SSCs as well as SSCs important to safety would potentially be exposed to 1 p$i overpressure, and a few SSCs important to safety may be exposed to heat flux of 12.6 kw/m 2 , which is comparable to the licensee's conclusion. Although the licensee's pipeline hazard impact evaluation used different models, assumptions, and methodology than the staff used in its independent confirmatory analyses , the staff's results and conclusions are consistent w h the licensee's results and conclusions. Therefore, the staff considers the licensee's hazard impact evaluation to be reasonable and acceptable.

&iN&lll)JE 6E61:1Rln' RELATEB INFOR:Ml<'nON

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