ML20236N079

Forwards Responses to NRC 870902 Comments 1,3,4,8,9,14,17 & 18 Re Environ Evaluation for post-defueling Monitored Storage

ML20236N079
Person / Time
Site:	Three Mile Island
Issue date:	11/05/1987
From:	Standerfer F GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
4410-87-L-0155, 4410-87-L-155, NUDOCS 8711160009
Download: ML20236N079 (5)

Text

-

w  ? l

/

V: -

GPU Nuclear Corporation

[ MNuclear  :: = = = 8o Middletown, Pennsylvania 17057-0191 717 944-7621 TELEX 84 2386 Wnter's Direct Dial Number:

(717) 948-8461 November 5, 1987

) 4410-87-L-0155/0209P I

US Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

Dear Sirs:

Three Mile Island Nuclear Station, Unit 2 (TMI-2)

Operating License No. DPR-73 Docket No. 50-320 Post-Defueling Monitored Storage Environmental Evaluation i NRC TMICPD Letter NRC/TMI-87-069, dated September 2,1987, provided 18 additional NRC comments on the Environmental Evaluation for Post-Defueling Monitored Storage submitted by GPU Nuclear letter 4410-87-L-0025, dated March 11, 1987.

Attached are responses to NRC comments 1, 3, 4, 8, 9, 14, 17, and 18.

GPU Nuclear is currently preparing responses to the remaining comments and ,

will submit them separately.

Sincerely,

/

. . Stander r T Director, TMI-2 RDW/eml Attachment cc: Regional Administrator, Region 1 - W. T. Russell Director, TMI-2 Cleanup Project Directorate - Dr. W. D. Travers l

8711160009 PDR ADOCK $Oh20 PDR l

GPU Nuclear Corporation is a subsithary of the Generci Public Utihties Corporation g (

-ATTACHMENT 1 l 4410-87-L-0155 NRC COMMENT l'  ;

~

b P. 5.0 ~ Paragraph-5

Both passive and forced ventilation discharges will involve co'ntrolled, HEPA filtered paths. Will the HEPA filters be single' stage or double stage?

GPU NUCLEAR RESPONSE

'For normal forced ventilation modes, double stage HEPA filters will be used. For the Reactor Building passive' mode, because forced ventilation is not used, a single stage HEPA filter will be used.

NRC COMMENT 3 P. 6.0 - Paragraph l What is the maximum batch size of liquid that might be collected prior to ,

processing? As in the case of the accident-generated' water, release of an untreated batch appears to be a credible, although unlikely accident. Please provide data on the maximum credible liquid release that would result from a failure to appropriately treat and monitor collected decontamination solutions.

GPU NUCLEAR RESPONSE In-leakage'which is not directly releaseable pursuant to 10 CFR 20, Appendix B, will be collected in the Auxiliary Building Sump for later processing. In addition to in-leakage, relatively small quantities of water used for decontamination will -l be collected.

Periodically, the sump will be pumped to the Auxiliary Building Sump Tank (ABST) and'then to the Miscellaneous Waste Holdup Tank (MWHT), or directly from the sump to.the MWHT, bypassing the ABST. When the MWHT is nearly full, the water will be processed.

The. capacity of-the MWHT is 19,518 gallons. The radionuclides concentration of this water prior to processing is difficult to predict due to the uncertain in-leakage pathways to the sumps and the collectable concentration of radionuclides in these pathways.

The radionuclides concentration of collected precipitation, based on 1987 records, is highest at the Tendon Access Gallery Sump where the range of radioactivity found is:

Gross Beta = 5.6 E-6 to 9 E-6 uCi/cc Cesium 137 = 5.2 E-6 to 8.1 E-6 uC1/cc Tritium = 3.6 E-6 to 4.8 E-6 uCi/cc

ATTACHMENT 1 4410-87-L-0155 t .

It would be reasonable to bound this concentration by a factor of 100 due to the pickup of residual contamination from the floor drains and sumps prior to water j transfer ,o the MWHT. However, even if the MWHT were to fail and its contents l I released, the leakage would be contained within the Auxiliary Building.and no l f release to the environment would occur. l

. Additionally, Section 3.4 of NUREG 0591, " Environmental Assessment: Use of EPICOR II at Three Mile Island," discussed the design features for spill prevention built into the EPICOR II system. It would seem reasonable that any evaluation of a

. liquid release from EPICOR II should be consistent with this document which analyzes the affects of an EPICOR II pipe break resulting in the release of the entire contents of the MWHT to the EPICOR buildings.

l l

NRC COMMENT 4 l' ,

P. 8.0 - Paragraph 1  ;

Please provide data on the radionuclides inventory of the portions of the Waste Disposal Liquid System that are not seismically qualified.

GPU NUCLEAR RESPONSE The nori-seismic components of the WDL system are of no consequence with regards.to the transport of fuel. An analysis of the resins in the condensate demineralizers indicates that the quantity of Ce-144 (the isotope of choice for tracing fuel) is less than LLD (i.e., maximum fuel load is less than 7.8 E-2 gms of UO2 ). The remaining mixed fission product loose activity in the system is approximately equal to 1 uC1.

NRC COMMENT 8 P. 13 - Paragraph 1 What is the basis for the assumption of 50 discharges of the Reactor Building atmosphere a. year? Page 28 indicates that entries will be made quarterly (during the initial period of PDMS it is expected that entries will be made monthly). Will the Reactor Building atmosphere be purged between entries as well as immediately prior to each entry?

GPU NUCLEAR RESPONSE 50 discharges of the Reactor Building atmosphere a year was assumed as a conservative basis for evaluation of environmental consequences. During the initial period of PDMS, it is expected that entries to the Reactoc 9Jilding Will be made monthlv. The Reactor Building is not expected to be purged between entries unless events occur which require an unplanned Reactor Building entry (e.g., ,

uxpected alarms, special inspections). In the early phase of POMS, initial grab l' samples of Reactor Building atmosphere will determine the need for pre-entry purge i

requirements.

~ ~

PW' y ,

, j

.. e .- *"

b FV '

ATTACHMENTS 1'

, w /4410-87-L-0155

• I

~NRC COMMENT 9-W

-l "P. IS; Table 3 ,x Will.the_AFFE atmosphere be purged prior!t o-entry? .Was the' concentration'of airborne contaminants'in'theLAFFB considered to be' the same as-in the. Reactor

' Building?-1 Please provide the basis for your answer. ,

1

'GPU NUCLEAR' RESPONSE' , i l'

The. Auxiliary and Fuel' Handling Building ( AFFE) Ventilation ' systems most. likely l

-.will be? purged' prior;to_ entry.to meet OSHA standards. The concentration of

.j ~

airborne" contaminants'in the AFHB is inconsequential when compared to the Reactor.

Building.- For-this reason, the AFHB purging was not, considered explicitly. Any

-potentially high contamination areas'in the AFFE will be,sufficiently sealed'so that no consequential source term will exist.

1

'l

=NRC' COMMENT 14'

.The values given'on Page 11, r, econ'd paragraph, and in Table'2, are for-transuranic. l' elements only.. What other radionuclides are. associated with the residual fuel?.

What are.their activities? Why were they not considered in-the analysis?~

GPU NUCLEAR RESPONSE The purpose ~of: Table 2 is to show the core inventory of significant transuranic' isotopes'in' order:to develop'a transuranic source term.for POMS.- Other . i radionuclides remaining ~during PDMS also are discussed in the PDMS Environmental' l

' Evaluation...' Based.on survey,results, the predominant radionuclides' remaining are l Strontium-90 and Cesium-137. GPU_ Nuclear response to NRC Comments 6 and 7 will l provide additional ~information on residual radionuclides.

NRC COMMENT 17 j

l{

TP0/TMI-188, p. A-3, indicates that the domestic water system will be used in support;of system flush. If 1" system flush'_' involves any action other than flushing .

l the sumps or the waste disposal liquid (WDL) system, please indicate.

GPU NUCLEAR RESPONSE

~Once system decontamination has been completed and TMI-2 is in PDMS, there would be no. foreseeable need.to routinely perform a domestic' water flush of any radiologically' contaminated system other than the Liquid Radwaste Disposal and Sump.

Drain Systems, including' sumps.,

I i

I

__._:2m.:.--.___._. -__.a._ __ _,.m_ ___

g s m '

rg-

"> ' I'

• ., .t , i _ ,f j

L,. f., !

j J~

. ATTACHMENT 1 4410-87-L-0155 f

.NRC COWENT 18

t=

.ilsItheenclosed.) stairwell /elevst'orshdft' seismically' qualified?L e ~GPU NUCLEAR RESPONSE-'

> The enclosedistairwell/e' levator shAf t is not seismicallyLaualified.' Seismic events.

were conceptually considered.inithe preparation of the PDMS Environmental-Evaluation.. It.has'been-concluded that the. consequences of.a safe shutdown-

~

' earthquake would.not exceed the dose ~for the fire scenario.-

\

i i

l

s .

.. {

..d i

(

-1

' I f

1 I

ls f, i i

i

__.m.____m'..__ _ _ . _ . _ )