ML18051A682

Forwards Addl Info Re post-accident Sampling Monitoring Sys (Pasm),Per NUREG-0737,Item II.B.3.Reasons for Not Using Charcoal Adsorbers in Ventilation Exhaust of Pasm Sys Listed

ML18051A682
Person / Time
Site:	Palisades
Issue date:	12/06/1983
From:	Johnson B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	Crutchfield D Office of Nuclear Reactor Regulation
References
RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.3, TASK-TM NUDOCS 8312090199
Download: ML18051A682 (5)

Text

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consumers Power company General Offices: 1945 West Parnall Road, Jackson, Ml 49201 * {517) 71;1$-0550 December 6, 1983 Dennis M Crutchfield, Chief Operating Reactor Branch No 5 Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT - POST ACCIDENT SAMPLING SYSTEM ADDITIONAL INFORMATION Consumers Power Company: letter dated August 12, 1983 *provided verification that the criteria in NUREG-0737 Item II.B.3 with exception of the Containment Atmosphere/Hydrogen sampling had been satisfied by the Palisades Plant post accident sample monitoring system (PASM).

The purpose of this letter is to provide additionalCiµformation\\"'s'l:k't~~ the reaso~s for not using charcoal adsorbers in the ventilation exhaust of the Palisades PASM system.

NUREG-0737 states that consideration should be given to charcoal adsorbers in the ventilation exhaust of the PASM.

The Palisades PASM system is designed as a closed system with the only potential for the escape of iodine to the ventilation plenum is from a leak in the apparatus or a premature evacuation of the off-gas system after a sampling procedure (operator error).

The charcoal adsorbers are not considered necessary for the following reasons:

1.

The system is environmentally qualified to the conditions experienced during an accident and a leak is unlikely to occur.

2.

During norm~l and accident operating conditions, the iodine release from the system is expected to be insignificant (see Attachment 1).

3.

Proper operating procedures and training will prevent the premature evacuation of the off-gas system after sampling *

- 83120901-99 831206 PDR ADOCK 05000255 p

PDR OC1283-0003AA-NL02

DMCrutchfield, Chief Palisades Plant PASM - ADDITIONAL INFO December 6, 1983 2

4.

The reactor coolant line in the system has an automatic isolation function initiated by a high coolant temperature.

5.

The accident sampling procedure requires two individuals, one to perform the sampling and one to monitor the radiation levels. If radiation levels exceed a predetermined level, the sampling process will be terminated and isolation of the system accomplished immediately.

Brian D Johnson Staff Licensing Engineer CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Attachment OC1283-0003AA-NL02

OC1283-0003B-NL02 L

ATTACHMENT 1 Consumers Power Company Palisades Plant - Docket 50-255 POST ACCIDENT SAMPLING SYSTEM ADDITIONAL INFORMATION December 6, 1983 2 Pages

I' I -*

E~IPMENT CORP.

P. O. BOX 127

• OCONOMOWOC, WISCONSIN 53066

• PHONE 414

• 567-7:?56 September 22, 1982 Consumers Power_Company, 1945 West Parna'il.

Jackson, MI_/ -~492.0l Attention:

Dear Joe:

Mr. Joseph Beer Roan P-24-418 Post Accident Sample Monitoring System

Palisades Plant P.O. #CPl0-5008-CQ Spec. #0330-1-775-51-31-35 SEC J.O. f/10058 Per our discussion of yesterday, I'm sending along a copy of the radia-tion report on the Ncdel "B" system \\.:hich we provided for Midland Units 1 & 2. While the Palisades and Hid land systems are both designated as

• "t:todel B", both were customized in accordance w-ith the engineer's direc-tives, as reflected in the specifications. This has resulted in a few major differences which should be borne in mind when using the report.

l. The Palis!ides Unit has 2-1/2" solid lead in 1/4" steel plate shielding on the right side and rear of the panel, with 1/2" of steel on the

• left _side.

The 'Mid land (GSf) Units have 1/2" steel sides and 1/4" steel at the back.

The Nid land CASP (Containment Ail:- Sample Panel) has S" of lead shot between 1/2" plates on both sides.

The front

{operating) wall of all units is cornposed of 7" of lead shot between 1/2" steel plates.

2. 1llc containment air is sampled in a separate pane 1 in the Mid land system.

necause the sample tubinr. routin~ is less complex, the Hidland containment air samplinc systrm has about 2oi; less tubing than l'alisadcs.

3.

111t' Mid land p.:mcls do not include provisions for:

(a) comwctions to the l;ross Garr.ma dt*tc-ctors and; (b) h:c1nt ol l'*mcl tspl&1sh box) r.t:;i.lJ s;u:1plin1_~.

1ltC' Nilll.11111 l',11wls, therl'Lorc, have kss tuuinr. and few penetrations th1*ourJl the shi.PlJ.

11H.'sc itl*1:1s \\.'ouhl tc*ut.l to increase the Palisades do::;c rate,,.-hl'I\\ C<imparC'c.I to the Mic.I l~1ml tlo~H.*ratc, H£'1'.;1nlinr. thf' i*1*lC';1~w of Iodine into th<* v1*ntilation systCT.l, we feel th.it.lily such n*h*.i.:.C',,.-ill lJe relatively i.11sir,11iticant ior the following

L l'otr.r 2 of 2 St*1*Lt*1:1tH'r 22, 1982 N1:. J<i!;q*h beer rrasuns:

t. 1llc liquid sample is routed directly to the waste connection and the cont~inrncnt air sample is returned to the containment. 1be operating 1*t()Ccdurcs. are* designed to minimize the tine which a hot" sample s11N1ds in the.panel;.it is,*co_ntained in the tubing, valves, and vcsscls*.. (luririg *the enttre p*eriOd..

The only chance for escape into the plenum "is via a leak *

. 2. The off-gas from the liquid sample is flushed to waste before the system is dried with the eductor.

Any iodine left in the piping would thus tend to redissolve and be carried to waste.

From the above, it can be seen that there are two possible sources for Iodine escape into the plenum, and from there to the ventilation system:

(a) through a leak in the tubing, or (b) premature evacuation of the off-gas system after a sampling procedure.

We feel that the fonner (a) is unlikely if the units are properly in-stalled and maintained, and that the latter (b) if *not a recurring con-dition will release negligible amounts of iodine into the ventilation system.*

If we can be of further assista_nce, please do not hesitate to call.

Very truly you~s, SHffRY I::QUIPHE.NT CORP.

!Uf!~d--JI

(;1i..v.- \\~ilkinson, Jr.

l'rot~r<im.Manager cc1 Clark Kahn, CPCo Palisades IJ.\\\\. Holder, SEC l.R. Ror.u::elfaenger, SEC Hlc -

10058