ML20030A349

Chapter 9 to Final Hazards Summary Rept for Big Rock Point, Radwaste Disposal

ML20030A349
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	11/14/1961
From:	CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
References
NUDOCS 8101090366
Download: ML20030A349 (16)

Text

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SECTION 9

.P_ADIOACTIVE WASTE DISPOSAL

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9.1

. AIRBORNE WASTES 9.1.1 General The off-gas system consists of hold-up piping, a 240-foot high stack and sufficient controls and instruments to:

I9 16 and O produced in the Provide sufficient decay time for N 9.1.1.1 reactor so that activity from these elements will not result in significant radiation exposure to plant personnel or the environs after release to the atmosphere via the main stack.

Provide for controlled release and dispersion of the noble gases, 91.1.2 primarily xenon and krypton, which may be released in signif-Provisions include icant quantities due to a fuel element rupture.

automatic closure features to prevent release of significant quan-tities of air-borne radioactive materials.

Keep radioactive particle escape 'o the atmosphere below safe 9.1.1. 3 limits.

91.2 Gaseous Waste Discharge Criteria Limits for discharge of gaseous radioactive waste are based on the ability to monitor both at the release point and in the environs to demonstrate that it is not likely that any individual will be ex-posed to radiation doses in excess of that permitted in licensing Since the limiting mode of exposure from radio-regulations.

gases is the external radiation fr'om the cloud of such gases, emission rate limits are based on a permissible dose of 500 The naturally oc-mrads per year at any point in the environs.

curring diversity is calculated and used'in establishing permis-(

Monitoring for radioelements other than sible emission rates.

l radiogases is performed as is appropriate to provide a high I

degree of assurance of the insignificance of release rates of Environs monitoring provides the such othe r radioelements.

information needed to confirm the general validity of emission rates established as permissible.

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9.1.3 Sources of Gaseous Wastes The gaseous wastes of concern are the off gases which leave via Both the main condenser air ejectors and the gland seal system.

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of these gas streams carry the same radioactive components and go to the stack after a decay period in the hold-up piping.

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l 9 1.3.1 The gases from the air ejector are approximately of the compo-j j

sition given in Table 9.1.

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TABLE 9.1 l

OFF GASES FROM STEAM JET AIR EJECTORS cfm at 130*F 1 atm g

Hydrogen 5

Oxygen

. 2. 5 -

Air 2.5-13.9 (max.)

Water vapor (to saturate) 0.5-3.1 (max. )

Activated & Noble Gases negligible 10.5 to 24.5 (max.)

9.1.3.2 Table 9.2 gives the ectimated release rate at the reactor core of the activation gases. Such rates are based on calculation of the activation products from the irradiation of water and of the amount of air expected to be in the reactor water. Such calculations, to-gether with the estimation of the travel path division between water and steam, have been confirmed by observation at Dresden.

TABLE 9.2 RATE OF EVOLUTION OF ACTIVATED GASES FROM REACTOR Gaseous Rate of Evolution Activation from Core in Steam, Products pc/sec 1 x 10-1 A-41 A-37 1 x 10-5 O 19 5 x 104 2

N 13 3 x 10 7

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N 16 1 x 10 N 17 2 x 103

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9.1.3.3 In addition to the activation product activity listed, there may be

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a small amount of nobic gas activity discharged during normal operation due to radioactive xenon and krypton isotopes. This radioactivity might arise as a result of a leaking fuel rod. It is estimated that a release rate of 100 pc/sec of noble gases might result from a leaking fuel rod. Fission products, other than l

noble gases, that might be released from a leaking fuel rod would be contamed by the water; it is estimated that a fuel rod leaking 100 pc/sec of noble _ gases, would result in approximately 6 x 10-3 k :-

pc/ml of-fission product activity in the water.

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S ction 9 Page3 9.1.3.4 The off gases from tFe g:and sea; condenser cor.sist esse tially 5

of air saturated with water vapor. Thes e ga tes a rc opected to be discharged at the rate of aboat 145 cim. Tre activated gases and noble gases in this system are re: cased at abou' O.1 per cert of the rate at which they a re released from the air ejector system.

I 9.1. 4 Methods of Asrur:ng Safe Re: ease ef Gaseou? War *es 9.1.4.1 The reactor co tainment vessel and portions of the turbine. building are provided with both forced and induced draft ventilatior. which pro-duces air flow f-om areaa of lea s* contamir.atten to more cortam-

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ination and then d:acharge to the atack.

A:1 po+edia:ly certaminated areas a re ventilated sc ac to avoid *he extetence of any hazardous condition to the plant proper or surracnding areas during norma;

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plant ope ra+ ion.

9.1.4.2 The off-gas ho;d-up line provides approv.;metely 30 minutes' decay

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time for air ejector off gare s.

This decay time rechee.= the N-16, N-17, and 0-19 act:vities t a r.egitgible level and also gives the operatcr time tc take action to minimize the need for cr to determine the requirement for plant sh:tdown in the event of high nob!e gas re-lease ratee. The gases from 'he ai ejectot off-gas holdup line are a!!

filtered through a high efficiency filter to remove all particulate matic:

prior to release in the stac k.

Details of the inonitoring system a re given in Section 7.12.

9.1.4.3 Dases from the gland (eal cordenser and tbc mechan: cal vacua n.

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pumps flow through a ecparate pipe which holds up the gases for 90 seconds before discharging up the stack.

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9.1.4.4 All process gases are mixed in the stack with the ventilation air befot e release. Approximate y 3d,000 CFM of ventilation air pro-

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vide initial dilution of tne radioactive gases. Two full capacity ventilation fans u e provided. Upon failure of the ope rating fan, the standby fun rta rta automatically. Failure of eitber or both k

fans 's annunciated in th contici rcom.

Desc ription of the ven-tilation system is giver. in Sectior. A.8.4 and details of the in-atrumentatior ayrrm for monitoring the proc e ss ga sec a re gwen

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in Section 7.12.

9.1.4.5 The hold-up piping has the efier of reducine t! e rad.cactivity cf

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the noble gases leaving the reactor by abcut one half prior to their relea se f r om the stack. The tall stack promotes dispersion

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into the atmosplere and reduces 12e radieic dose to the environs due to release of inese gasec.

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9.1. 5 Stack Eintss:on Cor side:ations ar d Umit=

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9.1. 5.1 The activatior gases in eter.m frarr-the core shown in Table 9.2 are subject to nawral and p'.anned reductia : f actora pr:or to being availab:e for stack ditcha:ge & rough tl.e a:r geetor and gland P90R ORIGINAL c

t Secticn 9 Page 4 Rev 1 (3/19/62) seal exhaust systems. In both systems, decay times are provided to reduce emission rates to insignificant levels on those fractions l

which' are available as a result of the process flow patterns. All gases listed are reduced to calculated emission rates to the stack of much less than one microcurie per second, with the exceptior.

of 10-minute half-life nitrogen-13, which has a calculated emission rate of about 40 pc/sec. Slight background quantities of radioisotopes of the noble gases, xenon and krypton, perhaps in the order of 100 pc/sec may also be emitted routinely. Such emissions, when subject to atmospheric diffusion from the high stack and the naturally oper-ating atmospheric diversity factors, will result in an annual radi-ation dose at any point in the envir ons of much less than one millirem.

Thus, essentially all of the permissible stack emission rate is reserved for use if needed in connection with possible noble gas releases from defective fuel.

9.1.5.2 The permissible emission rate from the stack depends on the r adio-isotopes to be emitted, the stack height and exit velocity, and the degree of wind direction diversity and atmospheric diffusion diver-sity which occurs in the plant area over the permissible dose period of one year.

9.1.5.3 nadioisotopes to be emitted are considered to be the " equilibrium" mixture of noble fission gases. This is somewhat conservative, as limited exper ience has indicated that gas leakage from defective fuel is more likely to be a more rapidly decaying " diffusion" mixture. In addition, the noble gas mixture emission rate limit is conservative if the emission consists of any of the activation gases still present at stack emission decay time. The conversion tactor from infinite cloud uniform concentration to hemispher i a1 geometry dose rates at various decay times for the equilibrium mixture is:

Decay Time pc/cc causing one mrad / hour 2 minutes

1. 0 x 10-6 30 minutes 1.4 I hour 1.6 I

8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 3.I 1 day 5.0 j

10 days 7.0 9.1.5.4 With the emission point limited to exhaust from the 240-foot high I

stack with an exit velocity of at least 40 feet per second, the sig-nificance of a stack release is a function of the wind charac-teristics at this level. Summary data from the 256-foot level of the Big Rock Point tower in the past year are presented in Table 9.3 by directions of various significance as follows:

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Secticn 9 Page 5 Rev 1 (3/19/62)

Wind Wind From Significance of Direction of Direction Azimuths Wind Movement From Plant No. 1 ~

280 -360 -20 Blowing inland, sparsely populated areas 2

30 -50 Blowing inland, toward Charlevoix (3 mi) 3 100 -230 Blowing over open lake 4

240 -270 Over lake, toward Petoskey & Harbor Springs (11 mi) 5 60 -90 Over lake, parallel to shore 6

Any Calm (less than 4 mph)

TABLE 9.3 WIND DIRECTION FREQUENCY, PERCENT; AND AVERAGE WIND SPEED,(mph) 256-FOOT LEVEL, ALL PERIODS OF DAY, BIG ROCK POINT Direction No.

I 2

3 4

5 6

1, 2 3,4,5 Nov 60 29(21) 1(12) 43(17) 16(23) 10(19)

T 30(21) 69(19)

Dec 60 37(20) 6(16) 31(19) 17(26) 7(25) 2 43(19) 55(22)

Jan 61 35(19) 3(11) 30(15) 15(19) 14(12) 3 38(18) 59(15)

Feb 61 17(13) 6(13) 32(14) 13(17) 26(14) 6 23(13) 71(15)

Mar 61 34(18) 9(14) 25(17) 6(17) 23(16) 3 43(17) 54(17)

Apr 61 42(15) 8(15) 19(14) 9(12) 20(17) 2 50(15) 48(15)

May 61 38(16) 3(14) 30(17) 12(14) 14(15) 3 41(16) 56(16)

Jun 61 24(15)

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33(14) 21(18) 17(16) 3 26(15) 71(16)

Jul 61 28(11) 2t cf 28(12) 18(12) 15(13) 9 30(11) 61(12)

Aug 61 31(12) 2(10) 35(14) 14(13) 12(14) 6 33(12) 61(14) d Total Period 32(l6) 4(14) 30(l6) i4(l8) 16(l5) 4 36(16) 60(16)

Overall wind speed,15 mph 9.1.5.5 Table 9.4 summarizes similar data for the period of the day be-tween midnight and 4 AM, when stable atmospheric conditions are of highest probability.

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Section 9 Page 6 L

TABLE 9.4 WIND DIRECTION FREQUENCY, PERCENT; AND AVERAGE WIND SPEED (mph);

256-FOOT LEVEL. MIDNIGHT TO 4 AM ONLY, BIG ROCK POINT Diraction No.

1 2

3 4

5 6,

1, 2 3,4.5 Nov 60 37(18) 0(00) 42(19) 8(26) 11(13) 2 37(18) 61(19)

Dec 60-40(22) 5(19) 33(20) 17(23) 2(26) 3 45(22) 52(21)

Jan 61 40(19) 1(04) 40(15) 7(17) 11(09) 1 41(19) 58(14)

.Feb 61 14(11) 8(10) 30(13) 15(18) 27(11) 6 22(;1) 72(13)

Mar 61 25(19) 10(17) 29(21) 6(25) 27(14) 3 35(19) 62(18)

Apr 61 41(15) 9(13) 24(16) 3(14) 19114) 4 50(15) 46(15)

May 61 36(15) 3(09) 37(17) 11(16) 12(12) 1 39(14) 60(16)

Jun 61 19(12) 6(13) 49(14) 11(II) 13(15) 2 25(12) 73(14)

J,11 61 27(11) 1(06) 46(13) 8(11) 14(13) 4 28(11) 68(13)

Total Period 31(15) 5t12) 37(15) 9(17) 15(12) 3 36(15) 61(15)

Midnight to 4AM Over-all Average Wind Speed,15 mph 9 1.5.6 Table 9.5 summarizes similar data for the period of the day be-tween noon and 4 PM, when etable atmospheric conditions are of loweat probability.

TABLE 9.5 WIND DIRECTION FREQUENCY, PERCENT; AND AVERAGE WIND SPEED (mph);

_256-FOOT LEVEL, NOON TO 4 PM ONLY, BIG ROCK POINT Direction No.

1 2

3 4

5 6_

1. 2 3,4,5 Nov 60 18(21) 4(11) 40(18) 30(23) 7(26) 1 22(19) 77(21)

Dec 60 3?(17) 5(10) 30(20) 20(21) 8(24) 0 42(16)

SS(21)

Jan 61 32(16) 3(13) 22(14) 25(!?)

15(14) 2 35(16) 63(15)

Feb 61 12(08) 9(19) 29(10) 11(16) 36(15) 3 21(13) 76(13) i Mar 61 40(15) 10(15) 19(15) 10(13) 20(17) 1 50(15) 49(15)

Apr 61 46(14) 5(21) 12(12) 16(11) 21(20) 0 51(15) 49(15)

May61 42(15) 3(17) 20t21) 20(14) 15(19) 0 45(15) 55(18).

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Jun 61 29(15)

O(00) 22(18) 40(20) 15(20) 4 29(15) 67(20)

Jul 61 43(09) 0(00) 10(13) 27(16) 14(15) 6 43(09) 51(15) l Total Period 32(13) 4(15) 23(14) 22(16) 17(15) 2 36(13) 62(15)

Noon to 4 PM Over-all Average Wind Speed,14 mph

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9.1. 5. 7.

Tableo 9.3, 9.4, and 9.5 indicate the somen. hat unusual and ad-vantageous meteorological conditions of the Big Rock Point site for garcous warte disposal. The high average wind speed of 15 mph, with 4 mph or slower winde present only 4 percent of t

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. Page 7 Ssction 9 Rev 1 (3/19/62) the time, indicate that better than average diffusion conditions

- will exist during any type of atmospheric stability. Middle-of ~

night wind speeds are actually higher than those for middle-of-

[2 day. Only about one third of the time will the stack plume be j

conveyed over adjacent land; the remainder of the time the h

plume will have a distance of at least 10 miles over open lake prior to encountering other land masses.

9.' l. 5. 8 Tables 9.6, 9.7, 9.8 and 9.9 correlate the wind directions with the various lapse rate conditions for the period of February 1961 through February 1962. The data for February 1961, do not include data for the first 9 days of that month. The data for-February 1962 include only the first 11 days of the month.

TABLE 9.6 FREQUENCY OF OCCURRENCE (PERCENT) OF UNSTABLE CONDITIONS AT LEVEL NO. 4 l

I Direction No. I No.2 No.3 No.4 No.5 Total Feb 5.04 0

4.61 0

0 9.65 Mar 6.05 0.67 3.36 0.81 0.40 11.29 Apr 2.08 0

2.64 1.I1 0.42 6.25 May 0.54 0

3.09 0.54 0.40 4.57 June 2.36 0

2.22 0.97 0.14 5.69 July 7.80 0.13 3.49 2.42 1.21 15.05 Aug 10.75 0,13 4.70 1.88 1.08 18.55 Sept 9.86 2.36 6.94 2.08 0.97 22.22 Oct 19.35 1.75 5.11 1.61 2.42 30.24

• Nov Dec 10.48 0.13 0.94 6.18 0.54 18.28 Jan 14.38 0.81 0.67 3.63 1.21 20.70 Feb 4.92 0

1.52 0.38 0.38 7.20 t

Average 7.80 0.50 3.27 1.80 0.76 14.14 I

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S2ction 9 Pcge 7A Rev 1 (3/19/62)

TABLE 9.7 FREQUENCY OF OCCURRENCE (PERCENT) OF NEAR t

NEUTRAL CONDITIONS AT LEVEL NO. 4 Direction No. I No.2 No.3 No.4 No.5 Total Feb 14.47 2.19 20.18 10.09 15.79 62.72 Mar 26.21 6.85 11.42 3.09 17.47 65.05 Apr 27.22 2.22 6.81 2.50 8.19 46.94 May 14.78 0.13 8.06 3.23 3.90 30.11 ii June 9.86 0.69 7.78 4.44 2.78 25.56 July' 15.99 1.48 11.96 6.45 3.49 39.38 Aug 20.43 1.61 12.37 7.80 3.49 45.70 Sept 12.08 2.22 27.08 5.56 3.47 50.42 Oct 25.00 2.69 11.96 2.69 2.96 45.30

• Nov Dec 20.16 3.09 37.90 12.77 3.76 77.69 Jan 25.94 2.15 30.11 11.96 4.17 74.33 Feb 11.74 2.65 29.92 13.64 9.47 67.42 Average l '-

2.33 17.96 7.02 6.58 52.55 TABLE 9.8 FREQUENCY OF OCCURRENCE (PERCENT) OF STABLE CONDITIONS AT LEVEL NO. 4 Direction No. I No.2 No.3 No.4 No.5 Total I

Feb 2.64 0.88 15.13 1.75 5.26 25.66 haar 4.17 1.61 12.23 1.61 3.09 22.72 Apr 13.06 5.28 13.89 5.42 7.36 45.00 May 20.56 2.02 19.09 7.39 3.09 52.15 June 11.67 1.94 27.08 12.50 5.63 59.03 July 10.08 0.81 20.16 9.01 3.63 43.68

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Aug 4.44 0

22.18 4.30 3.09 34.01 Sept 1.81 0.14 19.58 1.81 1.39 24.72-Oct 6.85 0.27 14.11 0.94 1.08 23.25 i

• Nov Dec 0

0 3.90 0

0.13 4.03 Jan 0.40 0.13 3.76 0.40 0

4.70 Feb 6.06 3.03 7.95 2.27 3.41 22.73 i l Average 6.81 1.34 14.93 3.95 3.11 30.14 l

Saction 9 Page 7B Rev 1 (3/19/52)

TABLE 9.9 FREQUENCY OF OCCURRENCE (PERCENT) OF VERY STABLE CONDITIONS AT LEVEL NO. 4 Direction No. I No.2 No.3 No.4 No.5 Total Feb 0

0.44 1.75 0

0.44 2.63 Mar 0.27 0

0.40 0.12 0.13 0.94 Apr 0.56 0.14 0.97 0.14 0

1.81 May 4.03 0.67 6.05 1.34 1.08 13.17 June 1.67 0

4.31 3.47 0.28 9.72 July 0

0 1.61 0.27 0

1.88 Aug 0.40 0

1.34 0

0 J.75 Sept 0

0 2.22 0.42 0

2.64 Oct 0.67 0

0.54 0

0 1.21

• Nov m

Dec 0

0 0

0 0

0 Jan 0

0 0.27 0

0 0.27 Feb 0.38 0

2.27 0

0 2.65 Average 0.57 0.10 1,81 0.48 0.16 3.22

• November data not included due to inoperative wind direction indicator on tower at Icvel No. 4.

9.1.5.9 During the portion of the time when either advection or nocturnal radiation surface-based inversions exist, the atmospheric sta-bility will prevent the stack pit'ime from coming to the ground.

Thus the plume is held aloft, permitting horizontal diffusion and significant radioactive decay of any material emitted. Any fumi-gation periods which follow will be of short duration and would I

have a high probability of occurring over the lake or at widely scattered overland locations.

9.1.5.10 The near neutral lapse rate condition, which produces a maximum ground dose rate appr oximately one mile downwind, was shown l

by the meteorological study to be the most limiting condition.

The near neutral lapse rate is defined as a change in temperature with height at a rate between minus 3 C per 100 feet of height I

and 0 C per 100 feet. The meteorological parameter s of Sutton's equation which are applicable to the B:g Rock Point area, for the above described limiting lapse rate condition, are as follows:

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Stack height (h) - 75 meters

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Average wind speed (ti) - 7 meters per second

Section 9 Page 8 Rev 1 (3/19/62)

Vertical diffusion coefficient (C ) - 0. I meters z

Horizontal diffusion coefficient (C ) - 0.4 meters y

Stability parameters (n) - 0.25 The "always safe" emission rate which would deliver 500 mrem per year, assuming unidir ectional wind and 100% near neutz al lapse rate, at the distance of maximum concentration is 4

5. 3 x 10 itc/sec. This emission re+a is based on an equilibrium mixture of noble gases in a hemispheric cloud after one-half hour holdup prior to release, as tabulated in 9.1. 5. 3.

9.1.5.11 Table 9.7 shows that the wind will convey a plume overland (Directions No. I and No. 2), during near neutral conditions,

21.25% of the time. Directions No. I and No. 2 represent a 140 se ctor. Using the parameters listed in 9.1.5.9, and the cloud width to the 50% point, the plume encompasses an arc of 14. 8. Thus the plume directional diversity factor is

9. 5; and the combined diver sity factor is 4 5.

4 9.1.5.12 The "always safe" emission rate of 5.3 x 10 pc/sec, corrected by the applicab1: diversity, becomes 2.4 curies /sec. Thus an annual average stack emission r ate of 2.4 curies /sec,will not result in radiation exposures in uncontrolled areas in excess of limits prescribed in 10 CFR 20.

9.1.5.13 The above emission rate is based on a combination of thcoi etical and practical considerations. The true indication of the long term acceptability of these emission limits is given by a proper site and environs monitoring program. Such a program must prove that the actual doses at points of gener al public exposure are within the acceptable licensing limits.

J 9.1.5.14 Since noble gases are the radionuclides which may contr ibute the more significant portion of possible environs dose, care-ful continuous monitoring for this mode of exposure is essential.

As radioiodines may be present, this type of monitoring also is planned. Radiogas monitoring is performed with approptiate instrumentation placed at suitable locations in the approximate five to fifteen mile radius from the point of emission. Radio-iodine monitoring is performed by vegetation sampling at the same network of poritions. The natural background shown by these monitortug methods is being established in advance of operation.

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S2ction 9 Page 8A Rev 1 (3/19/62) t 9.'l.5.15 Present plans are to establish radiogas monitoring at appropriate positions in the vicinity, establish the back-ground, and continue operation of the network during facility operation. Following establishment of radioiodine background, sampling will be continued at a frequency commensurate with the degree of need indicated by appropriate off-gas line and stack monitoring.

9.1.5.16 Integration of monitoring network results with the stack emission continuous monitors and the plant site wind direction recorders provides the essential information for adjustment of the per-missible stack emission control limits upward or downward as is appropriate to provide a high degree of assurance that general public ra'diation exposures are' always well within permissible annual dose regulations.

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Section 9 Page 9 Rev 1 (3/19/62) 9.l.6 Monitoring and Contz ol 9.1.6.I Protection against excessive radioactive gas release rates is i

afforded by several continuous 2 adiation monitors on the process off-gas system (as indicated in Section 7.12). In the event that radiation release rates exceed the continuous safe discharge limit of 2.4 curies per second, a valve in the off-gas line may be manually closed to retain the gases. - At the higher level of 10 curies per second, this valve is closed automatically by a monitor signal. Valve closure r equires plant shutdown and correction of the cause of high release.

After suitable decay, the r etained gases, which have been held in the off-gas piping, are released and plant operation r esumed.

9.1.6.2 Continuous monitors on the stack provide a record of both total activity and nitrogen-13 activity of all air and gases re-leased fr om the stack. A particulate sampler is also pro-vided on the stack to detect any significant release of radio-active particles. These monitors serve to indicate any changes or trends in relaase rates of radioactive gases or particles, as well as total amounts released. Means are also provided for periodically measuring the concentrations of individual r adioisotopes so that they may be related to appropr iate limits. (See Section 7.12.2) 9.1.7 Explosion Hazard A potential hazard in the off-gas system may exist due to the pr esence of a stoichiometric roixture of hydrogen and oxygen.

Actually, the probability of a hydrogen-oxygen reaction occur-ring is very low, since the off-gas system is closed and no sour ce of ignition or spark is present, and the gas is saturated with water vapor so no static spark should r esult.

However, the system is designed to withstand the calculated pressures encountered due to such a reaction.

i 9.2 LIQUID WASTES 9.2.1 Sour ces and Quantities 9.2.1.1 The radioactivity of the liquid wastes is due to activation of corrosion products formed in the nuclear steam supply system and the possible escape of fission products from fuel element cladding defects. The corrosion products 'esult from the materials of construction of the system and consist of com-pounds of iron, chronium, nickel, cobalt, zirconium, alu-minum, manganese, copper, etc. Radioactivity results from neutron irradiation of these elements. Fission products, on the other hand, consist of a very wide range of elements. The total mixture of radioisotopes which can be present in the i

nuclear steam supply system at any particular time is ther efore quitc complex. It can.be character ized only in general by saying that most of the chemical elements can be pr esent. The total

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Ssction 9 Page 10 Rev 1 (3/19/62)

,l concentration is very low, since water quality is maintained very high.

3 9. 2.1.'2 The liquid radioactive wastes, which are estimated to be about 2000 gallons per day, during normal operation are collected from equipment leakage, equipment drainage, and sample col-lection. Demineralizer regeneration and washdown are estimated to add about 7000 gallons per day. The system is designed to be capable of handling approximately 70,000 gallons per day.

9.2.2 Waste Discharge Criteria 9.2.2.1 Limits for discharge of liquid radioactive waste ar e based on the ability to monitor both, prior to release, and also in the environs, to demonstrate that it is not likely that any individual will be ex-posed to r adiation doses in excess of that permitted in licensing regulations, recognizing that the permissible dose period is one year.

9.2.2.2 Those liquid wastes which are likely to contain radionuclides of plant origin are sampled, analyzed as appropriate, and released on a batch basis only, to provide a high degree of assuran:e of contr ol. Other flowing liquid streams are continuously monitored at time of release to the environs.

9.2.2.3 Liraits employed for release decisions recognize that certain radioelements cannot be present from process origin, with regard to use of " unknown" radionuclide limits. Where appropriate,

analysis will be done to permit use of more r calistic permissible limits.

9.2.2.4 In general, liquids will be considered appropriate for release if the gross activity of plant origin in the effluent can be regulated so that it does not exceed an average, for a one-year period,. of 10-7 J2c/cc. Recognition of diffusion and radioactive decay in the lake normally will not be employed to meet permissible dose considerations unless appropriate special monitoring is performed.

9.2.3 Operational Flexibility of the System 9.2.3.1 The liquid radioactive waste disposal system consists of collection sumps, receiver tanks, tank mixing eductors, strainers, filter,

demineralizer, hold-up tanks, concentrator, pumps, interconnect-ing piping and instrumentation. Floor drains and other waste waters which normally have a high solids content are routed to a " dirty" sump which in turn pumps to one of two " dirty" 5,000-gallon rad-waste receiver tanks. When one tank is full, the waste is collected in the other " dirty" receiver tank and the contents are thoroughly mixed before grab sample analysis is made of the water just col-lected. The tank contents are then pumped directly to the discharge canal or through the filter and demineralizer system into one of the waste hold tanks depending on the radioactivity of the water. The water processed and collected in one of the waste hold-up tanks is then re-sampled, before being pumped to the condensate tank, canal,

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or returned to one of the receiver tanks for reprocessing. The final routing is dependent upon the waste concentrations meeting ap-propriate disposal requirements.

Section 9 Page 11

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9.2.3.2 Waste water which normally has a low total solids content is collected in a " clean" sump and routed to one of two " clean" 5000-gallon waste receiver tanks. When one tank is full, water is collected in the second tank and the first batch is processed eilmilarly to li piid wastes from the " dirty" rau-waste. receiver tant s.

9.2.3.3 Acidic wastes from condansate demineralizer regeneration, chemical laboratory and various decontaminating areas throughout the plant are routed to a " chemical" receiver tank. The solutions collected in this tank are then processed as required. Acidic or basic solutions are adjusted to a pH of 8 to 10 before processing. The high solids low radioactivity

" dirty" water is normally discharged to the canal without treatment, before dischargo. The low solids high radioactivity waste are normally filtered, demineralized, and returned to the condensate tank for reuse in the system.

The high solids high radioactivity wastes are concentrated by evaporation and the concentrate stored. Concentrated liquid wastes are stored in a 5000-gallon tank, and provision is made for future tankage. Solutions of low solids and low radioactivity are released to the discharge canal or demin-eralized, depending on the water demand from the condensate storage tank.

9.2.4 Types of Construction The construction of the liquid waste disposal system is con-sistent with conventional construction practice where possi-ble. Where necessary, equipment is placed behind shield walls. Tanks and piping containing radioactive materials are contained in concrete rooms or pipeways. Any overflows, leaks, or spills are thur retains i and collected. Leakage to the ground is thus eliminated. inside the plant leakage is also minimized and routed tc suitable collection points to minimize potential contamination spread.

9.2.5 Discharge to the Lane 9.2.5.1 Plant effluent which is potentially radioactive and is normally discharged into Lake Michigan includes:

a) those collected and routed to the liquid radioactive waste system for treatment, monitoring, and discharge; and b) cooling and service water which can only become radio-active as a result of a leak in the heat exchangers.

Snction 9 Pa gc.12 9.2.5.2 Wastes routed to the liquid radioactive waste system are released to the lake only under batch control. Service and cooling water streams are released continually, but are monitored so any significant system leaks which may intro-duce radioactive material may be detected and corrected.

Most of the equipment containing radioactivity is cooled by water in a closed loop. This water is in turn cooled by se rvice water. Thus, in most cases, radioactivity can only enter the service water if leaks are present in two heat exchangers at the same time. Exceptions are the main condenser and waste concentrator condenser in which any leakage is inward. Drawings M-108 and M-132 show the radioactive waste disposal system indicating quantities and activities which may go to the la ke.

9.2.5.3 Much of the radioactive liquid waste is returned to the plant for reuse after treatment, both to minimize activity release to the lake and to conserve water. However, such wastes as resin regeneration solutions and dirty floor drains are of no value for reuse and are discharged to Lake Michigan when within discharge limits. Nonradioactive wastes discharged to the lake consist of those usually originating from fossil-fired power plants. Examples are noncontaminated floor drains, storm sewers, and certain process effluents.

Sanitary wastes are not included in this discussion.

9.2.5.4 Discharged liquid wastes are released to the discharge canal which empties into Lake Michigan. The primary steam emptying into the discharge canal is the cooling water from the main condenser. This water is not radioactive since the main condenser is under vacuum while the cooling water is under pressure. Thus, cooling water leaks into the con-denser if a condenser leak occurs and condensate cannot leak into the cooling water., Because of its large volume (about 50,000 gpm at full power), this cooling water is avail-able for diluting radioactive wastes.

9.2.5.5 All untreated radioactive waste liquids are stored in steel tanks placed in concrete waterproof undergro%d vaults. Any accidental underground leakage of radioactive waste liquids would encounter the low permeability and high ion exchange properties of the natural overburden. Any liquids reaching the fractured limestone stratum would be limited in their i

movement toward the lake by the low horizontal velecity (0. 05 feet per day) in this stratum.

9.3 SOLID WASTE 9.3.1 Sources and Types of Wastes

9. 3.1.1 Spent demineralizer resin from the cleanup, condensate and radwaste demineralize rs.

9. 3.1. 2 Contaminated tools.

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9. 3.1. 3 Worn-out contaminated equipment.

9. 3.1. 4 Contaminated clothes, paper rags, used filters, and mis-cellaneous operating materials.

9. 3.1. 5 Use'd process equipment, such as control rods, fuel chan-nels', ion chambe rs, etc.

t 9.3.2 Methods of Handling and Disposal

9. 3. 2.1 Demineralizer resin is sluiced to a 10.000-gallon storage tank which is sized to receive wastes for approximately five years. Provision is made for future tankage.

9.3.2.2 Contaminated tools and equipment are stored in the under-ground concrete solid waste burial vault.

9.3.2.3 Contaminated clothes, paper, rags, and other soft waste t

are baled into small bundles and stored in the solid waste 4

burial vault.

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9. 3. 2. 4 Before the solid waste tank or vault gets full, a new tank will be installed, or the solid wastes will be removed by a I

licensed contractor for storage or disposal elsewhere.

9.3.2.6 Auequate space is provided in the fuel pool for storage of irradiated ion chambers, control rod blades, and fuel channels until such time that they can be moved into per-manent disposal.

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