ML19016A135

Response to Request for Additional Information - License Amendment Request to Revise the Technical Specifications - Permanently Defueled Technical Specifications

ML19016A135
Person / Time
Site:	Pilgrim
Issue date:	01/10/2019
From:	Halter M Entergy Nuclear Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2.18.075
Download: ML19016A135 (10)

Text

~E nt er ~ Entergy Nuclear Operations, Inc.

1340 Echelon Parkway Jackson, MS 39213 Tel 601-368-5573 Mandy K. Halter Director, Nuclear Licensing 2.18.075 January 10, 2019 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

SUBJECT:

Response to Request for Additional Information - Licen se Amen dmen t Request to Revise the Pilgrim Nuclear Powe r Statio n Technical Specifications - Permanently Defueled Technical Spec ifications Pilgrim Nuclear Power Station Docket 50-293 Renewed License No. DPR-35

REFERENCES:

1. Entergy Nuclear Operations, Inc. letter to NRC, "Technical Specifications Proposed Change - Permanently Defueled Technical Specifications" dated September 13, 2018 (ADAMS Accession No. ML18260A085)

2. NRC email to Entergy Nuclear Operations, Inc.,

"Pilgrim: Request for Additional Information (RAI) - Pilgrim Post-Decommis sioning Technical Specifications (POTS) License Amen dmen t Request (LAR)

(EPID: L-2018-LLA-0268), dated November, 16, 2018 (ADAMS Accession No. ML18320A129)

In Reference 1, Enter gy Nucle ar Operations, Inc. (Ente rgy) submitted a license amen dmen t request to the U.S. Nucle ar Regulatory Commission (NRC) for approval of the Permanently Defueled Technical Specifications.

In Reference 2, the NRC requested additional inform ation concerning the LAR.

Attachment 1 to this letter provides the Entergy respo nse to the NRC request for additional information.

This letter contains no new commitments and no revisi ons to existing commitments.

If you have any questions or require additional inform ation, please contact Mr. Peter J. Miner at (508) 830-7127.

I declare under penalty of perjury that the foregoing is true and correct. Executed on Janua ry 10, 2019.

Letter Number 2.18.075 Page 2 of 2 Respectfully, MKH/sd/mp Attachments:

1. Response to Request for Additional Info rmation - License Amendment Reques Revise the Pilgrim Nuclear Power Stat t to ion Technical Specifications - Permane Defueled Technical Specifications ntly cc:

USNRC Regional Administrator, Region I

USNRC Project Manager, Pilgrim USNRC Resident Inspector, Pilgrim Planning and Preparedness Section Chie f, Massachusetts Emergency Manage Director, Massachusetts Department ment Age ncy of Public Health, Radiation Control Prog ram

Attachment 1 Letter Number 2.18.075 Response to Request for Additional Information - License Amendment Request to Revise the Pilgrim Nuclear Power Station Technical Specifications -

Permanently Defueled Technical Specifications

Lette r Numb er 2.18. 075 Attac hmen t 1 Page 1 of 7 ARCB - RAI #1 a}

"Plea se provid e the follow ing information regarding the radio active waste handl ing accident:

a) Which sectio n of the UFSA R describes the radio active waste handl ing accid ent and what chang es are propo sed to this section that reflect the perm anen tly shut down and defue led condition of the reactor?"

ENTE RGY RESP ONSE a) Currently, Secti on 14.5.6 of the Pilgrim Nucle ar Powe r Station (PNPS) Upda ted Final Safet y Analy sis Repo rt (UFS AR) evalu ates the poten tial effect s resulting from conde nser hotwell or radwa ste syste m tank failures inside the Radw aste and Turbi ne Building. In addition, it evalu ates the failure of the offgas piping

, an air ejecto r disch arge line break, and the ruptu re of the Cond ensat e Stora ge Tanks (CST). In gener al, this sectio n addre sses radwa ste syste m failures. Section 14.5.

6 of the PNPS UFSA R does not includ e the analysis of the radwa ste handling event addre ssing the drop of a High Integ rity Conta iner (HIC).

After the certifi cation s are subm itted for perm anent cessa tion of opera tions and remo val of fuel from the react or vesse l for PNPS in accor dance with Title 1O of the Code of Fede ral Regu lation s (CFR ) 50.82(a)(1 )(i) and (ii), and docke ted pursu ant to 10 CFR 50.82(a).(2),

powe r opera tions can no longe r occur. As a result

, anoth er event will becom e the limiting event regar ding the radwa ste syste m accid ent when the Perm anen tly Defue led Techn ical Spec ificati ons (POTS) are implemented. This event will involv e a radio active waste handl ing event (i.e., a HIC drop event) (see the respo nse to NRC ACRB - RAI #1 e). The discu ssion s in Secti on 14.5.6 of the PNPS UFSA R will be replaced with a discu ssion of the HIC drop event as descr ibed in Calculation No.

M142 1, Offsite Dose s Follow ing the Drop of a High Integ rity Container. This section will be retitled Radw aste Syste m Accid ent

- HIC Drop Event. It will include the follow ing subse ctions : Analy tical Metho dolog y, Assum ptions , Inputs, Radiological Cons equen ces/R esults , and Refer ences . In addition, a new table will be provid ed to addre ss the HIC Drop Sourc e Term Relea se Activity. Thes e chang es to the PNPS UFSA R will be reviewed unde r the provis ions of 10 CFR 50.59.

The addition of the HIC drop event into the PNPS UFSA R will be benef icial durin g the active decom missi oning phase. Following the trans fer of all of the spent fuel to the Indep ende nt Spen t Fuel Stora ge Installation, the Fuel Hand ling Accid ent will no longe r be possi ble and the analy sis will be removed from the PNPS UFSA R. At that time, the analysis of the Hf C drop event will becom e the sole rema ining event addre ssed in Secti on 14 of the PNPS UFSA R.

Letter Num ber 2.18.075 Attachment 1 Page 2 of 7 ARC S - RAI #1 b)

"Please provide the following information rega rding the radioactive wast e handling accident:

b) Is the licensee proposing a new, or diffe rent kind of, OBA from any accident previousl evaluated? If so, which TS(s) is added or does y it impact?"

ENTERGY RESPONSE b) No. Currently, Section 14.5.6 of the PNP S UFSAR evaluates the failure of the condense hotwell or a radwaste system tank with the r primary release of radionuclides to the environment due to the release of gaseous iodine in chemical equilibrium with iodine in liquid phase of the spillage. In addition, it evalu the ates the failure of the offgas piping, an air ejector discharge line break, and the rupture of the CST. In general, this section addresses radwaste system failures. While the HIC drop event is not currently addresse in Section 14.5.6 of the PNPS UFSAR, it was d an event that could occur during normal operations that was considered bounded by the events presented in Section 14.5.6 of the PNPS UFSAR.

The HIC drop event will become the new boun ding radwaste system accident after the plant is permanently shut down and defueled (see the response to NRC ACRB - RAI #1 e) when the POTS are implemented. The even t description was provided in the POTS license amendment request (LAR) to demonstr ate that the analysis does not impact any technical specifications or require any new technical specifications.

The HIC drop event occurs in the open air.

Thus, the releases involve an unfiltered, ground level release that takes no credit for the operation of any systems, structures, or components (SSCs) to mitigate the conseque nces of the event. As such, it is not considered a design basis accident (OBA) as defined in Chapter 15 of NUREG-0800. The radioactive waste handling accident does not impact existing technical specifications or require the addition of new technical specificat ions.

Lett er Num ber 2.18 .075 Atta chm ent 1 Pag e 3 of 7 ARC S - RAI #1 c)

"Ple ase provide the following informat ion regarding the radioactive was te han dling accident:

c) Is the radioactive was te handling acci den t maintained in a licen see- cont If so, wha t is the nam e of the docu men rolle d docu men t?

t? If not, will the radioactive was te han acci den t be add ed to the Pilgrim UFS dling AR? "

ENT ERG Y RESPONSE c) The HIC drop eve nt is not currently addressed in Section 14.5.6 of the PNP was an even t that could occu r during S UFSAR, it normal ope ratio ns that was cons ider the events pres ente d in Section 14.5 ed bou nde d by

.6 of the PNP S UFSAR.

Afte r the certifications are submitted for perm ane nt cessation of ope ratio ns fuel from the reac tor vessel for PNPS and removal of in acco rdan ce with 10 CFR 50.82(a)(1)(i and dock eted purs uan t to 10 CFR 50.8 ) and (ii),

2(a)(2), pow er operations can no long a result, the HIC drop even t will beco er occur. As me the most limiting even t for radw aste failure when the POTS are implemented syst em

. As part of the impl eme ntat ion of the disc ussi ons in Sec tion 14.5.6 of the POTS, the PNP S UFSAR will be replaced with a the HIC drop eve nt as described in Calc disc ussi on of ulation No. M1421, Offsite Dos es Foll Drop of a High Integrity Container. This owin g the section will be retitled Rad was te Sys

- HIC Drop Event, and will contain the tem Acc iden t information desc ribe d in the resp onse ARC S - RAI #1 a). The se changes to to NRC the PNPS UFS AR will be reviewed und prov ision s of 10 CFR 50.59. er the

Letter Num ber 2.18. 075 Attachment 1 Page 4 of 7 ARCS - RAI #1 d)

"Please provide the following information rega rding the radioactive waste handling accident:

d) Is it the licensee's intent of including the radioactive waste handling accident as "gen information" of "other accidents considered" eral and not a proposed new, or [different] kind of, OBA?"

ENTERGY RESPONSE d) The radioactive waste handling event was included in the POTS LAR as general information of other accidents considered and not a proposed new, or different kind, of OBA. As discussed in the response to ACR B - RAI #1 b), the HIC drop event does not meet the definition of a OBA since there are no SSCs that are credited to mitigate the event.

Lette r Num ber 2.18.075 Attac hmen t 1 Page 5 of 7 ARC S - RAI #1 e)

"Please provide the following information regar ding the radioactive wast e handling accident:

e) Does the radioactive waste handling accid ent bound the radiological consequences of the Radwaste System Accident DBA s found in Pilgri m UFS AR Section 14.5.6 when Pilgrim is in a permanently shutdown and defueled cond ition?"

ENTERGY RESPONSE e) Yes. After the certifications are submitted for permanent cessation of operations and removal of fuel from the reactor vessel for PNPS in acco rdan ce with 10 CFR 50.82(a)(1 )(i) and (ii), and docketed pursuant to 10 CFR 50.82 (a)(2), powe r operations can no longer occur. As a result, the HIC drop even t will beco me the most limiting event for radwaste system failure when the POTS are implemented.

It will be the radwaste system accident that is addressed in Section 14.5.6 of the PNPS UFSAR. The table below provides a comparison of the 2-Ho ur Exclusion Area Boun dary (EAB) and 30-D ay Low Population Zone (LPZ) thyroid doses for the limiting liquid radwaste tank accid ent and the HIC drop event.

Table - Dose Consequences - Failure of a Cond ensate Stora ge Tank and HIC Drop Event 2-Hour EAB 30-Day LPZ 2-Hour and 30-Day Event -Thy roid -Thy roid EAB and LPZ (rem) (rem) Thyroid Limit (rem)

Calculation M1424 - Failure of CST 2.0BE-02 2.06E -04 30 Calculation M1421 - HIC Drop Even t - Limiting Distance within the 2.?E-02 1.58E-03 30 Protected Area Fence As discussed in the POTS LAR, Calculation No.

M1421, Offsite Dose s Following the Drop of a High Integrity Container, analyzes a design basis wast e handling event involving a drop of a HIC. The table above shows the 2-hou r EAB and 30-d ay LPZ inhalation doses to the thyroid for the HIC drop event.

Calculation No. M1424, Radiological Conseque nce of a Liquid Radwaste Tank Accident, analyzes a design basis liquid radwaste system accident involving the failure of a storage tank that contains a significant quantity of liquid radioactive material. The event considered in this analysis is a liquid radwaste system accid ent wher e the entire contents of a storage tank are lost. The analysis conservatively assu mes that the contents of the tank were at the Technical Specifications 3.6.B maximum limit of 20 µCi/cm 3 of iodine isotopes at shutdown. The same isotopic distribution as the design basis main steam line break accident is assumed. Credit is taken for the 46 days deca y post-shutdown prior to the implementation of the POTS. The iodine release fraction is conservatively calculated based on NUREG/CR-5950, Rev. 3, Iodine Evolu tion and pH Control, and the released fraction of the total contents is instantaneously released to the atmosphere. Therefore, the mixing or dilution of iodine isotopes within the Radwaste or Turb ine Building is not credited, nor is the additional deca y during the time period of dose accumulation, 2-hours for the EAB and 30 days for the LPZ. For each offsite dose location, the bounding

Lett er Num ber 2.18 .075 Atta chm ent 1 Pag e 6 of 7 atm osph eric dispersion fact or (X/Q) and breathing rate are used to dete rmin e inhalation dos e to the thyroid. the Calculation No. M 1424 determined the dose rates for the limiting tank failure follo wing 46 day s of deca y post-shutdow (CS T) n prio r to the impl eme ntat ion of the POT table abo ve sho ws the 2-ho ur EAB and S. The 30-d ay LPZ inhalation dose s to the thyr failure of a CST , and demonstrates that oid for the these results will be bou nde d by the event. HIC drop

Lette r Num ber 2.18. 075 Attac hmen t 1 Page 7 of 7 ARC S - RAI #1 f)

"Plea se provi de the following information regar ding the radioactive wast e hand ling accident:

f) Plea se explain why the Radwaste System Accid ent DBA s found in Pilgrim UFSA R Section 14.5.6 are no longe r applicable when Pilgrim is in a perm anen tly shutdown and defueled condition?"

ENTERGY RESPONSE f) Currently, Secti on 14.5.6 of the PNPS UFSAR evaluates the failure of the cond ense r hotwell or a radwaste system tank with the prima ry release of radionuclides to the envir onme nt due to the release of gase ous iodin e in chemical equilibrium with iodine in the liquid phas e of the spillage. In addition, it evalu ates the failure of the offgas piping, an air eject or disch arge line break, and the rupture of the CST. After the certifications are submitted for perm anen t cessation of operations and removal of fuel from the react or vess el for PNP S in accordance with 10 CFR 50.82 (a)(1)(i) and (ii), and dock eted pursuant to 10 CFR 50.82(a)(2), power operations can no longe r occur. As a result, the offgas piping and air eject or discharge line will no longe r perform a function in the perm anen tly shut down and defueled state. Thus, the failur e of those comp onen ts is not required to be addre ssed since those SSCs will no longe r be required to be operable or functional to supp ort decommissioning activities, such as spen t fuel pool storage, cooling and trans fer operations.

The radwaste tanks and CST will continue to be utilized for some time following the perm anen t shut down and defueling of the react or. A radioactive spill from these tanks will still be possible until the tanks are drained of their contents. However, as described abov e in the respo nse to ACR B - RAI #1 e), the cons equences of a failure of a liquid radwaste stora ge tank (i.e., t.he most bounding was deter mined to be the failure of the CST) 46 days following perm anen t shutdown of the reactor is bounded by the HIC drop event. Therefore, the analysis of the HIC drop even t will be the new bounding radwaste system accid ent when the POTS are implemented.