ML20058K910
| ML20058K910 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 06/28/1972 |
| From: | Larkin W NORTHERN STATES POWER CO. |
| To: | Muntzing L US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 9104260270 | |
| Download: ML20058K910 (12) | |
Text
.[
W Vlls y 1
NSP NORTHERN STATE 5 POWER COMPANY M IN N E A PO Ll e. MIN N E G OTA 58401
- 5
[. e R$
June 28, 1972 F E 9'
63 L
2 Mr L Manning Muntzing
- h. j r
E Director of Regulation
(; 4 United States Atomic Energy Commission h2 C
Washington, D C 20545 gj j
Dear Mr Muntzing MONTICELLO NUCLEAR GENERATING PLANT Docket No. 50-263 License No. DPR-22 Attached for your information is a copy of a letter from NSP to Dr Howard A Andersen, Chairman of the Minnesota Pollution Control Agency, which was delivered yesterday.
It outlines the current off-gas release rates at the Monticello Nuclear Generating Plant and the status of the construction of the new off-gas system.
Also attached is an April 2, 1971 letter to Dr Andersen which is refer-enced in yesterday's letter.
In our effort to share fully with the MPCA the reasons for the delay in completion of the off-gas system, extensive reference is made to the requisite safety reviews and licensing process within the AEC.
Unfortunately, some of the early news media releases on yesterday's letter implied that the AEC regulatory function was the major cause for the delayed in-service date of the new off-gas system.
We believe that sharing the full context of the letter with you will put our comments on the licensing and safety review process in the proper per-spective.
As Mr McElroy's letter states, "Our original, rather basic concept grew into a much larger, highly complex project...."
Under these circumstances, an exhaustive review by the AEC was both necessary and desirable.
The elapsed time for AEC regulatory approval was anticipated by people with
') &].h g
\\
y e
.3 m.
30t2 B
A*
l uguaan WgChp
/hel 9104260270 720628 e
CF ADOCK 0500 63, g
MO2 5
dl I @
NORTi
.R N CTATEC POWER CON ANY Page 2 June 28, 1972 Mr L Manning Muntzing adequate knowledge of the technology involved.
We con-tinue to avidly support the regulatory process needed to assure safety in nuclear plant operations, and sincerely hope our explanation of delays to the MPCA did not unduly bring public criticism to the AEC.
If such is determined to be the case, please understand thct it was inadvertant and accept our sincere apologies.
Yours very truly h
R Wade Larkin Group Vice President Power Supply
,,f.
NSIB NORTHERN STATES POWER COMPANY M IN N E A f*Q U S M S N N E S OTA 55401
- 3
. _ ' 4 iy June 27, 1972 p, y, h
F 3
A g
b O
c s
b B
Dr Howard A Andersen, Chairman t i Minnesota Pollution Control Agency ha 5
1072 Plummer Lane t,
4 o
Rochester, Minnesota 55901 Dear Dr Andersen There is a matter of some importance regarding the Monticello plant that I must communicate to you.
You may recall Mr Robert H Engels ' letter of April 2, 1971, to you in which he inforn d you of our plans for modifications to the Monticello plant tt reduce radioactive gaseous emissions.
(A copy of that lette. is attached for your reference.)
We initiated these changes to fr rill a commitment made to the MPCA in May, 1970, concerning off-o storage tanks to hold up gaseous emissions to permit additior il radioactive decay before release.
In that letter 1r Engels said:
"With the plant codifications described, we can assert with confi-dence the plant w? ll not exceed the gross beta-gamma rate limits for gaseous releases now set out in the Minnesota permit.
- Further, we pledge that pending installation of this equipment, the plant will not be allowed to exceed these gross limitations -- even if it means the plant must be run at less than full capacity.
The fuel cycle will not be extended as a result of any of the described plant modifications."
NSP filed a technical specifications amendment for modifications to the off-gas system with the Atomic Energy Commission the day of the letter to you, April 2, 1971.
We hoped, as was stated in the letter, that installation of the new facilities would be completed by the end of 1971.
As you know, we experienced considerable delay in receiving the authorization for the changes from the AEC.
A major reason for this delay was that we were breaking new ground in developing an over-all concept that had never before been applied i
to an operating nuclear power plant.
Because of this, the concept was subjected to painstaking examination by the AEC which resulted
)
in significant modifications to the original proposal.
Many of j
these modifications had to do with assuring safe operation of the new system.
Our original, rather basic concept grew into a much larger, highly complex project costing more than seven times our l
\\
i e
e 3600
Dr Howard A Andersen Page 2 June 27, 1972 original estimate.
In addition, changes since April, 1971, in Codes of the American Society of Mechanical Engineers have delayed i
procurement and delivery of some components for the new system.
Our technical people and engineering design consultants had numerous conferences during 1971 with representatives of the AEC's Division of Reactor Licensing in an effort to speed approval.
In addition, a subcommittee of the AEC's Advisory Committee on Reactor Safeguards became involved in review of the modifications.
We ordered some of the new system components in 1971 and we began basic excavation and structural work for the modifications late in November, 1971, in spite of the fact that we had not yet received authorization from the AEC for the changes.
Mr Engels said at that time:
"In keeping with our commitment to the people of Minnesota, we feel we must proceed as far as we can with excavation and structural work.
When we receive approval, and we hope it is soon, basic structures should be ready for equipment installation."
After its extensive review, the AEC authorized the off-gas modifi-cations late in January, 1972.
We have continued with all speed on the project.
It is a job of some magnitude, as indicated by its estimated cost of $4.5 million.
We anticipate that the project will be completed by early spring of 1973.
he plan to shut the plant down at that time for the purposes of tying in the new off-gas system, making some core modifications and completing a turbine overhaul.
In the meantime, we are confronted with the fact that gaseous emissions from the plant with its existing design are approaching the point where they will exceed the gross beta-gamma limits proposed as an annual average by the MPCA.
The annual average that we committed ourselves not to exceed is 10,000 microcuries per second.
The Monticello plant is now releasing at the rate of about 30,000 microcuries per second at full operation and the release rate probably will increase before we can complete installation of the of f-gas modifications.
As is predictable with a boiling water reactor, the gaseous release rate has been increasing as we have maintained full power levels and as the fuel has become older.
However, plant gaseous emissions will continue to be far below the average annual release rate of 270,000 microcuries per second allowed under the present AEC license.
I am sure that you can recall as clearly as we do the situation in the months prior to our decision to make the of f-gas modifications.
We had gone through a protracted AEC licensing hearing during which a $112 million plant was standing idle.
The proposed MPCA permit I
t P
Dr Howard A Andersen Page 3 June 27, 1972 i
h for the plant was under litigation, but we were and still are determined to meet the spirit of your agency's wishes.
Our decision to make the off-gas modifications and our information-sharing program with the agency are evidence of this determination.
Although Mr Engels did not specifically state it in his letter to you, our commitment not to exceed the gross beta-gamma release limits for gaseous emissions in the proposed MPCA permit was based on our full expectation that the modifications would be completed by the end of 1971 or at the latest early in 1972, well before the gaseous emission rate would have reached present levels.
Because t
of the delay beyond our control, we are now faced with the follow-ing extremely difficult alternatives regarding the commitment to you:
1.
Run the Monticello plant at less than full capacity l
from now until the scheduled spring shutdown.
We estimate that this would require reducing plant i
output from its present level of about 550,000 l
kilowatts to about 275,000 kilowatts immediately and to progressively lower levels until the new l
system goes into operation.
2.
Run the plant at full operation until we reach the MPCA's proposed gross beta-gamma limit, then shut the plant down until next spring.
We calculate that 7
this shutdown would have to occur around mid-July, 1972.
3.
Shut the plant down now and replace certain fuel rods.
l Experience with other boiling water reactors has shown that selective fuel rod substitution does not reduce gaseous emissions significantly.
We estimate that it would be at least six months before refueling could i
commence because new fuel would have to be ordered and AEC license requirements met for refueling operations.
4.
Shut the plant down after the summer peak demand period i
or run it at less than full capacity until the scheduled spring shutdown.
In either case, we would still exceed l
the MPCA's gross beta-gamma figure.
Further, because of the need for capacity to replace that lost at Monticello, scheduled maintenance periods for other NSP i
generating units would have to be postponed, potentially jeopardizing reliability of these units.
This could also disrupt the maintenance schedules of other interconnected utilities.
l l
l 6
l l
Dr Howard A Andersen Page 4 June 27, 1972 j
l 5.
Ask you for a release from our commitment and continue present plant operations until the scheduled spring l
shutdown.
Alternatives 1, 2 and 3, if any one were implemented, would seriously jeopardize our ability to meet anticipated peak elec-l trical demands of our customers this summer.
Our projected summer peak is 3,678,000 kilowatts.
Our reserve capacity at the time of the projected summer peak will be 434,000 kilowatts if all existing NSP equipment is available for service and if new generating i
capacity outside our system from which we have contracted purchases is completed.
It is readily apparent that if Monticello is not available for our sun r peak demands, we not only will be without f
reserve capacity, but in fact will have insufficient capacity to l
carry our own load.
Our ability to completely meet our customer load would then depend on the availability of surplus power from j
others, a very uncertain prospect.
Thus, our utility responsibility does not permit us to consider 1,
2 or 3 as acceptable alternatives.
Under alternative 4, we still would exceed the gross beta-gamma figure and disrupt our maintenance schedules.
This alternative t
also presents environmental trade-of fs.
With reduction of gener-l ating capacity available from Monticello, we would at times have to operate older fossil-fuel plants or buy more power from outside I
our system if it were available.
Any decrease in the output of Monticello would result in increased emissions from fossil-fuel plants.
In our judgment, Monticello full power operation is a l
cleaner answer.
l I have reached the last alternative.
I believe it to be the most realistic and responsible course that we can take as this region's power supplier.
I therefore ask you to release us from our commit-ment not to exceed the gross beta-gamma limits, while we proceed l
as rapidly as possible toward completion of the off-gas modifica-t tions.
I regret that both of our organizations are in this position.
I do not believe that our request places you in a position of having to weigh against the health and safety of f
Minnesotans.- You may wish to contact the Minnesota Department of Health regarding the health aspects of continued operation of the l
plant until the new system goes into operation.
t i
- ~
- _1 Dr Howard A Andersen Page.5 June 27, 1972 I
I will be happy to discuss this situation with you at any time.
I look forward to hearing from you.
Sincerely
\\
I f
[\\ / i. s s
)
David F McElroy President t
i l
cc - The Honorable Wendell Anderson Grant J Merritt Dr Warren R Lawson 4
l f
f I
I i
l 1
MSE3 NORTHERN STATES POWER COMPANY uiN u t a mou s. uiN w a sot
- s e4os 2 9
- T>
ao...,...a y yi y
C.
> :,-4 c:
o
- r.
..I r--
m April P. 3971
[ 7.3
- r.. -
n to 3
n, r
c, -. n o
n p
m a
C3 ve m * -<
n n 5
-* O h,
Dr. Howard A. lin harc -n Chnirman Mi.ineEcts. Pclluticn Centrol Agene;.
1070 Plumber lane Rechester Minnecotu %931
Dear Dr. Andercen:
With cur Mcnticello plant ncv in cporation, I am writing to indcrm ycu cf USP's plans for the cperatien cf thic facility.
I'm sure ycu are ovare cf our Ccmpnny's Ulmce to cpend whatever is r > quired to ersure that the plant will h9ve no criverse effect; cn public hcalth or esfety.
Or. Terruary 20, 1970, Earl E.mld, Chairman of cur Board of Direetcr.n.
tertified before the Joint Cc=mittee of Ccncreer cn Atomic Energy as fcllour :
"We are villing to provide electrical cervice to the pecple of
.he state en whatever bacia they *. ant it.
We are not in any rence challenging the right cf the Statc cf Xinnerets to regulete in -
rearcnable canner any of eur actit w.
Compliance with the Minm 0cta
[
pcrmit it not a matter c f mone). '
Tc carry out thir commitment, hSP todny vill file with the AEC in Wachincten, D. C., refety dosicn infernsticn fcr ch8n,-r that will materially r?duer radioactive diccharge at our Menticellc pinnt. Thcce modificatienc, m: r confident, will make it pocsible fcr ur tc> meet virtually every ctaners which had been cdvcested by the PCA.
NSP will rnke three n.odificaticnc to the plan + decign. We enticipate that thoce vill enable the plar t to meet find in coma ences better the grces limits fer radic-active releases conteined in the permit :ce the plant iscued by the PCA cn Mey 26,1969 The proposel modifications are:
A.
Installation of a hydrcgen/cxygan recombiner. Its purpose ic to convert a suostantial pcrticn cf the caceous releares to vater.
I 1
36CD i
NORT. ZRN OTATED POWER CON ANY Dr. Heward A.
Mierrn F1D ce E April P. Irrtl The racembiner will reduce the volume of off-gar released to t he atmocphere by approximately 30 percent. Monticellc will be the first larre nuclear pcVer plant in this country to utili.e such equipment.
F.
Installat ion of an eff-ras heli-up cystem having not less than a 50-hour retention capabilits.
The plant in presently deri,7 mi to hold such gares Ior 30 minutes. This new system har the capability to ecmpress the eff-gaces into large cpecially decirned steel underground tanks built to exacting nuclear ccdec. Thic gas in there heli to permit radicactive decay before release.
With 50-hour er more retentien, nite boundary radietien levele vill on the average be reduced nc t lecs than 95 percent. Tha druatic reduction is chown en the at tached graph.
It might be noted that cperating conditicas may extend the actual retenticn perici to es much as 72 hourc, reculting in a 99 7 percent reduction.
Ve have requested early AEC approval so we may proceed quickly with construction. We hope te ecmplete installation of both the recombiner and the hold-up cystem by the end of the year. A design contract for both recombiner and the system hold-up cyctem was let several months aEo and the conceptual design is new complete. In anticipation of apprcpriate approvals, crders soon vill be placed with manufacturers to begin fabricetion of the equipment. NSP's effort to incorporate cuch a system is among the first in the industry and Menticelle vill be the first large nuclear generating station in the United States cperating with such a system. I anticipate it vill set the standard of performance by which others will be mescured.
C.
Inste11stien cf an activated charcoal filtration syctem in the stack.
It is the recer=endat ion of the state's consultant t hat the charcoal filters, cperated in ecncert with the gac retention system, vill give further aceurance that virtually no radicactive iodine vill appear in the environment.
Engineering feacibility studiec by KSP have been conducted over the past year on a national and international basis. Te cur kncvledge, Monticello will again be the first nuclear generating station in the United States with such charcoal filters.
The system design of the charcoal filters is almost ecqlete.
It will take apprcximately cix weekc to install after approvals have been received. Orders have been placed with manufacturers to begin fabrication of the equipment.
NOR'T r4ERN GTATED POWER CONr ANY 8
Dr. Wward A. Andersen Pare 3 April 2. 1071 r
The ecst of these modifications will be substantial.
Hevever, these modifica-tions will insure the Monticello plant utilizes the most advanced environmental protection develcpments in boiling water reacter nuclear power generation.
j Further, va are confident these modifications vill rake it pcssible for ur to I
meet mest of the requirements of the PCA permit.
The permit fer the Monticello plant issued by the PCA on May E8,1969, contains tvc categories of release limitations.
One is a grcss beta-gamma release limita-tion for all isotcpes as a group. The other is an annual average and a 7-day consecutive release limitation for each individual isotcpe.
I Based on the test advice and analysis which could be secured, and assuming installation of the three plant modifications, ve are villing to assert that the plant vill meet the gross beta-Essma limits fcr all liquid releases new set out in the Minnesota permit. To assure this, release of liquid vaste batches will be extended over the longest practicable time period consistent with meeting the stated radioactivity limitations. We can at this time also assure you the liquid tritium releases from the plant to the river will not exceed 1 percent of the ABC limits. Operating experience may permit betterment cf that figure.
With the plant modifications described, we can assert with confidence the plant vill not exceed the gross beta-ge=ma release rate limits for gaseous releases nov set out in the Minnesota permit. Further, we pledge that pending installation of j
this equipment, the plant vill not be alleved to exceed these Eross limitations --
even if it means the plant must be run at less than full capacity. The fuel cycle vill not be extended as a result Of any of the described plant moiifications.
We believe the facts reeffirm NSP's commitment to construct and cperate the Monticello plant to the highest possible standards cf environmental prctection, and certainly to meet the goals and cbjectives of the Agency when the permit was fcrmulated.
ESP will cocperate with all state agencier in meeting our common goals. ESP has expanded its environmental monitoring program to include all monitoring recem-mentatiens by the PCA. This monitcring program is being conducted in cocperatien with the Minnesota Department cf Health and the FCA. We are villing to continue to cocperate with the PCA in the interpretation of this data and its application to plant cperatien.
1 When the full secpe cf cperating conditions is determined af ter sufficient cperating ;
experience and if any significant departures from design expectations cecur, we renew our effer made at the August 11, 1970, PCA meeting to meet with the A ency 8
and the AEC to discuss whet apprcpriate action may be necessary.
Soon we vill be discussing in detail with you the specifics cf our Prairie Island plant. I em pleased to announce ve are hcpeful of implementing a sero emission concept recently announced by Westinghouse, the nuclear systems centractcr for this facility.
l l
1 i
l
NOR.4ERN CTATE3 POWER CC,.PANY Dr. Hoverd A. Andercen Page L April 2. 1071 There must be a etrenuous effert by goverreient and the power inductry to selve the prcblems of environment.
k'e pledge our cc:=itment, and we vill verk with the PCA and the envirc:miental leadership in our comunity to achieve the goals.
Thank you for this cppertunity to tell you abcut our planc for these facilities.
Sincerely.
ROBEPT H. E" GELS
?rnident cc:
Mr. Grant Merritt Attachment i
I
j Ficunt t If fIC1 OF MONTICtLLO Of F-GAS SYSTEM MODIF tCATsON ON RADIATION DO51 CONTRIBUTION AT PL ANT SOUNDARY i
i r
insakm.nimuwooseenou': :::*
- t :t:+:3 ;;: m
~
- 11!!L
.oniomattv =svattio
- ;; *
- r,41 svitau iawie.iu vai
..+4 4,.
444 4 4. 44,4, 4.r
...l 4,
4
. i.
....a r.4 4
a
- 9 44 9++$
l-8
,s t.e t 4 1
4 44.-
I
.$,499
[
O 4,
..t.
..,4.
.+4 g
bott 4.*6**1 1
44+4*i'
'r DOSI$ 8R5 #416 D 04 A stat etwG 8&CTOk D8 1 79
", j *,
- I
'+
Pf wlEC / Comit va ut V AND A COhYttuous ats j1.***
+
-4. 4 IJE CTOR mittatt mate Of O t?0 CUmsfl Pim
- .*4
... +..
11COhD ME atuRI D af T1 a 30 Maht'Tf1 SauPa t DEC AV 4
e s
i
.f.
P
-l
, s., *.4 e..
g
+4 r
t 94 4+44.
4
.,. 4 4... + + t4 g
g 4-1.
g-
- 4. 4. w.444 4.
+. 4444
{
5 s.
(
......44...
I e
t
...+
+4.
E
~ 00% -
M o
.... 44 4..
l.
4 4
+4-
. 44 j
4+
+
4 t. +4 +-. 4 +.
++
e
,,. 4 4.
,4..
.44
..4-....
I 4.4; g
...... 4 3
..}.. 4,4 +4 -
t e.- -.
q..
a.
3 w
-}
..4 4
...4. 2.,..
g
- i..ge-i.
44+#
r
=
- r..
. 4.....
4
..e++
4
.4 4-y
(
f,,
,,v..c.t
..t m.......m.......
4,/./,_////. //_ /.Alfff7//rY,,(/r.U$y...
/p ec,., e...,.....,... t.~.c.,
7
- -4 7
i
,0,. x4 W E / 4 !8 7/%d!$Nd,/' W N N,.4,v4-i
..,.4
.. f,
,3
)
... 444 f
44 44+ 4+
e 4 H44+4+
.j
.}
~
. ~ 4 4 4 +44 -
~'
..e e
one Dost eaow 4.'.. 44 4,+t4
+
-444 a
4 w0D*f stp systtu
-. ERPICTI D ANhual go 4 9, u.44y4,4.
,,,.. 9
,, DO,
o 44 4 44,-
Ev574 W 2 0018t M'Y## ***;;]!*]1
.e -
l-f ;l; -
-g
- t.
8 3D a0 00
.0 900 130 See eeourt Os PIf ts TION Of Of f cA5 pose m AD+0ACityt DECav f
j f
v b
J