B13489, Annual Radioactive Effluents Dose Rept for 1989

Annual Radioactive Effluents Dose Rept for 1989

ML20033G483
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	12/31/1989
From:	Mroczka E CONNECTICUT YANKEE ATOMIC POWER CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
B13489, NUDOCS 9004100074
Download: ML20033G483 (21)

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ANNUAL RADIOACTIVE EFFLUENTS DOSE REPORT; t

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t JANUARY-DECEM' BER 1989:

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l DOCKET NO. 50-213 1

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General Offices

• Seiden Street, Berlin, Connecticut US.Y[E 5[N(([=~s.~."

P.O. B0x 270 7["$"'i[ 2'.*. 7 Q HARTFORD, CONNECTICUT 061410270 4

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March 28, 1990

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Docket No. 50-213 i

B13489 Re:

10CFR50.36a U.S. Nuclear Regulatory Commission Attention:

Document Control Desk Washington, DC 20555 Gentlemen:

Haddam Neck Plant Annual Radioactive Effluents Dose Report In accordance with the requirements of 10CFR50.36a and the Technical Specifi-cations, a copy of the Annual Radioactive Effluents Dose Report is herewith submitted.

This report includes a summary of the assessment, of maximum individual and population dose resulting from routine radioactive airborne and liquid effluents for ti e period of January through December 1989.

Copies of the report are being forwarded in accordance with the provisions of 10CFR50.4(b)(1).

Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY h/h/C Y

E.'Uf Mroczka(/

Senior Vice President cc:

W. T. Russell, Region I Administrator A. B. Wang, NRC Project Manager, Haddam Neck Plant J. T. Shedlosky, Senior Resident Inspector, Haddam Neck Plant I

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TABLE OF CONTENTS o

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5fCTION P. AGE I

1.0 INTRODUCTION

1 2.0 0FF 5ITE 00$E INFORMATION 2

3.0 Ol5CU5510N OF RE5 ULT 5 5

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TABLE 1 0FF.51TE DOSE COMMITMENT (Al#80ANf) j l

TABLE 2 0FF 5ITE D0$E COMMITM2NT (Ll0UlD) l

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I TABLE 3 WHOLE BODY DOSE COMPARl50NS 1

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Appendix A INCREASED DOSE CONSEQUENCES RESULTING l

FROM HADDAM NECK DEORIS INDUCED FUEL 1

FAILURES i

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1.0 INTRODUCTION

e This annual report presents a summary of the estimated off site radiation doses for routine releases of radioactive materials in airborne and liquid effluents from the unit. These include the annual population dose commitments (person rem) for the area out to a 50 mile radius from the site, the annual average dose commitment (mrem) to the population and the annual maximum dose commitment (mrem) to any real member of the public.

The maximum gamma and beta air doses from gaseous releases are also presented.

The radiation doses resulting from the calendar year of altborne and liquid effluents are integrated over a 50 year time span, taking into account the effective decay and removal of the radioactive materials contributing to the dose for each individualin the population. The population dose commitment is the summation of the calculated individual doses with units of person rem.

The doses are compared with the regulatory limits and with the annual average population dose commitments from natural background and other sources to provide perspective.

In addition, this report contains an Appendix providing information on the higher than normal airborne effluents and doses which occurred at Haddam Neck during the third quarter of 1989.

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2.0 0FF liTf DOSE WPORMATION I

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l In accordance with the requirements of the Technical Specifications and l

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Regulatory Guide 1.21, the off site dose to humans from the airborne and I

i liquid radioactive effluents of Haddam Neck have been calculated.

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These estimations are performed using measured radioactive effluent data, f

l measured meteorological data, and calculational models developed by the U. 5. Nuclear Regulatory Commission (NRC).

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The dose estimates generally tend to be conservative due to the use of r

j conservative assumptions in the calculational models. More realistic estimates of the off site dose are obtained by analysis of the environmental monitoring I

data. A comparison of the doses estimated by each of the above methods will be presented in the Annual Radiological Environmental Monitoring Report.

l Appendix A also contains a comparison of these methods for special Samples l

collected during September 1989.

j 2.1 Calculation of Population and Maximum individual Dose Commitment i

l l

I Population dose commitment is defined as the total radiation dose retelved I

by the specified population during a specified period of time from an identified source of radiation. For purposes of this report, the population is taken to be within the area surrounding the nuclear site out to a 50 mile i

radius.

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The radiation doses resulting from one calendar year of airborne and liquid j

j effluents are integrated over a 50 year period, taking into account the radioactive decay and biological elimination of the radioactive materials 2

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contributing to the dose. The population dose commitment (units of person-rem)is the sum of the calculated individual doses.

The dose calculations involved the input of three types; radioactive source

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term data, site specific data, and generic factors. The radioactive source term f

(units of Curies) is obtained from the Semiannual Radioactive Effluents i

t Report. The site specific data includes the meteorological data (wind speed, j

direction, stability, etc.) to calculate the transport and dispersion of airborne i

radioactive effluents, dilution factors for liquid effluents, the population distribution and demographic profile surrounding the site divided into 16 f

compass sectors. Other site specific data include the annual average production of milk, meat, vegetation, fish, and shellfish. The generic data includes the annual average consumption rates (inhalation of air and l

ingestion of fruits, vegetables, leafy vegetables, grains, milk, poultry, meat, fish, and shellfish), and occupancy factors (air submersion and ground i

i irradiation, shoreline activity, swimming, boating, etc.) for determination of l

dose to the individual who would receive the maximum dose (maximum l

individual).

All these factors are input into the appropriate dose model for converting l

radioactive airborne and liquid effluents data into population and individual dose commitments, f

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a.

Airborne Radioactive Effluents Maximum individual doses and population doses due to the release of noble gases, radiolodines, and particulates were calculated using the computer code GASPAR0),

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The GASPAR code uses the semi infinite cloud model to implement the

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dose models of N.R.C. Regulatory Guide 1.109 (October 1977).

l The values of average relative effluent concentration (X/Q) and everage relative deposition (D/Q) used in the GASPAR code were generated using

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a meteorological computer code which implements the assumptions f

l given in Section C of NRC Regulatory Guide 1.111, " Methods for I

Estimating Atmospheric Transport and Dispersion of Gaseous Effluents in j

Routine Releases from Light Water Cooled Reactors."

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The annual summary of hourly meteorological (15 minute increments) l l

data collected for the year is not included in this report but is available

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from computer storage. This data includes wind speed, direction and f

atmospheric stability, and joint frequency distributions.

I Releases from the 175 foot vent stack are considered as mixed mode l

(partially elevated and partially grounci). The Pasquill stability classes were determined using the temperature gradient between the 33 foot and 196 foot levels of the meteorological tower, f

The GASPAR code was run for continuous releases through the vent l

(building ventilation) and batch releases through the vent (waste gas i

i tanks, vent header, volume control tanks, and containment purge). The i

resulting doses were then summed to determine the total dose.

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Lieuld Radioactive Effluents Maximum individual and population doses due to the release of l

radioactive liquid effluents were calculated using the computer code

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LADTAP(2). The code implements the dose models and parameters given in l

Regulatory Guide 1.109 (October 1977),

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2.2 Calculation of Gamma and Beta Air Org I

Maximum gamma and beta air doses due to the release of noble gases were calculated using the computer code GASPAR.

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1 3.0 DISCUSSION OF RESULT 5 l

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Airborne Effluents i

For population doses, the GASPAR code calculates the dose to the whole 4

body, GI tract, hone, liver, kidney, thyroid, lung, and skin from each of the following pathways: direct exposure from the plume and from j

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ground deposition, inhalation, vegetation, cow's milk and meat, 1

,i The values presented are a total from all pathways; however, only the l

l whole body, skin, and maximum organ dose are presented. The maximum organ dose in all cases was to the thyroid, and thus, the dose to i

all other organs wa6 less than that shown for the thyroid.

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For the dose to the maximum individual, the GASPAR program calculates i

the dose to the same organs listed above for the following pathways, L

direct exposure to the plume, exposure from ground deposition, i

inhalation, and ingestion of vegetation, meat, cow's milk, and goat's milk. The doses are calculated for adults, teenagers, children, and infants separately, l

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3 For the plume and inhalation pathways, the maximum individual dose is ll j

calculated at the off site location of highest decayed X/Q where a i

potential for dose exists.

j For the ground deposition, the maximum individual dose is calculated at I

the off site maximum land location of highest X/Q and highest D/Q where l

a potential for dose exists.

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For the vegetation pathway, the maximum individual dose is calculated at the vegetable garden of highest D/Q. For the meat, cow's milk and goat's milk pathways, the calculated dose is included for the maximum individual's dose only at locations and times where these pathways

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actually exist. Doses were calculated at the cow farm and goat farm of maximum deposition. The doses presented in Table 1 are the maximum J

doses observed.

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To determine compliance with 10CFR50 Appendix 1, the maximum i

individual whole body dose only includes the external pathways (plume and ground exposure) while the maximum individual organ dose only includes the internal pathways. Population doses include all applicable i

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pathways, The air dose includes only the dose due to noble gases in the plume.

Hence, if the ground shine contribution was significant, there may be cases where the maximum whole body or skin dose is greater than the maximum gamma or beta air dose.

l Maximum individual, population doses, and air doses are presented in

,r Table 1. Note that the third quarter doses are an order of magnitude 6-i

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j higher than normal. Appendix A provides detailed information on the I

reasons for the higher doses that quarter.

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b.

Llevid Effluents i

i The LADTAP code performs calculations for the following pathways: fish, i

shellfish, algae, drinking water, irrigated food, shoreline activity, l

swimming, and boating, in the vicinityof Haddam Neck, the shellfish, algae, drinking water, and irrigated food pathways do not exist, and thus, only the other pathways are included in the totals. The population

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doses consider all applicable pathways within 50 miles, f

Doses are calculated for the whole body, skin, thyroid, GI LLI, bone, liver, f

kidney, and lungs. Calculations are performed separately for adults, i

teenagers, and children.

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Table 2 presents the doses to the whole body, thyroid, and the maximum organ dose. Unless otherwise noted in the table, the doses given are

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I adult doses.

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Analvsis of Results The doses are smallin comparison to the dose from natural background radiation. The statistical expectation of health effects from the calculated radiation dose due to plant operations is insignificant.

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For perspective, Table 3 presents a comparison between the doses due to

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plant operation and doses received from other sources such as the naturally occurring background levels. The table also presents the legally allowed levels from 40CFR190.

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l FOOTNOTES l

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GASPAR Dose code, K. F. Eckerman, hington, D. C.. Revised Febru Radiological Assessment Branch, U. 5.

Nuclear Regulatory Commission, Was j

1976.

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(2)

LADTAP U. S. Nuclear Regulatory Commission; Washington, D. C.

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Tatde 1 OFFSITE DOSE COMMITMENTS (AIRBORNE)

Connecticut Yankee-1989 Airborne Effisents 1st Quarter 2nd Ovarter 3rd Ovarter 4th Quarter l

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,1. Maximum Air Dose (mrad)

Beta 6.05E-01 @.4mi NNE 1.87E+00 @ 3mi NNW 1.19E+01@.3mi NNW 1.06E+00 @ 3 mi NW j

Gamma 2.21E-01 @.4mi NNE 6.10E-01 @ 3mi NNW 3.50E+00@ 3 mi NNW 6.17E-02 @3mi NW t

i 2. Maximum Individual Dose (mrem) i

e. Whole Body (External) 131E-01 @.4mi NNE 3.60E-01 @3mi NNW 2.06E+00 @ 3 mi NNW 3.63E-02 @ 3 mi NW j

b. Skin (External) 3.66E-01 @.4mi NNE 1.13E+00 @3mi NNW 7.04E+00 @ 3mi NNW 7.11E-01 @ 3 mi NW i

c. Thyroid (Internal) 6.52E-03 @.4mi NNE 2.53E-02 @.5mi NW 1.02E+00 @.4 mi NNW 3.94E-02 @ 3 mi NW i

(teen)

(child)

(child)

(teen) i3. Population Dose (Person-Rem)

(0-50 Miles)

e. Whole Body 5.81E-01 7.43E-01 4.22E+00 1.52E-01

b. Skin l

l 1.85E+00 2.59E+00 1.69E+01 3.14E+00 i

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c. Thyroid i

5.81 E-01 7.44E-01 5.43E+00 2.89E-01 l

!4. Average Dose (mrem)

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i (0-50 Miles) i

c. Whole Body 1.24E-04 1.58E-04 9.00E-04 3.24E-05 2

b. Skin 3.95E-04 5.51E-04 3.60E-03 6.70E-04

c. Thyroid 1.24E-04 1.59E-04 1.16E-03 6.16E-05

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l Tatde 2 OFFSITE DOSE COMMITMENTS (LNMJID) 1 Connecticut Yankee-1989 i;

Liquid Effluents 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter t

1. Maximum individual Dose (mrem)

a. Whole Body 2.29E-02 2.81 E-02 1.86E-02 2.26E-02

b. Maximum Organ 3.2SE-02 (teen) 3.31E-02 (adult) 2.29E-02 (child) 3.13E-02 (teen)

(liver)

(liver)

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(liver) 1 l

c. Thyroid 2.57E-03 1.22E-02 9.60E-03 2.15E-02 i

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2. Population Dose (Person-Rem) j (0-50 Miles) i

a. Whole Body 1.85E-02 2.16E-02 1.54E-02 1.83E-02

5. Maximum Organ 3.08E-02 (liver) 2.95E-02 (liver) 2.26E-02 (bone) 2.99E-02 (liver)

c. Thyroid 2.24 E-03 8.38E-03 6.16E-03 1.26E-02 I

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3. Average Dose (mrem) l (0-50 Miles)

a. WholeBody 3.94E-06 4.61E-06 328E-06 3.90E-06

b. MaximumOrgan 6.57E-06 6.29E-06 4.82E-06 6.38E-06

c. Thyroid 4.78E-07 1.79E-06 1.31E-06 2.69E-06

a Table 3 COMPARISON OFWHOLE BODY DOSES Annual Radiation I.

D wes from Station Effluents-1989.

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A.

Maximum Individual-Liquids 0.0922 8.

Average individual - Liquids - (0-50 miles) 0.000016 C.

Maximum Individual-Airborne 2.59 D.

Average individual - Airborne - (0-50 miles) 0.0012 j

II.

Limits from Nuclear Power Plants A.

Maximum individual (40CFR190) 25 l

15.

Doses from Other Sources A.

Natural Radiation Sources in Connecticut - Cosmic.

Terrestrial, Food Products, and Radon 270 B.

Radioactivity from Building Matenals j

(varies from Wood to Stone House) 12-34 C.

Air Travel (Round Trip - Cross Country) 4 D.

Smoking (1 pack / day) 2-20 i

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l Appendix A l

l l

Increased Dose Consecuences Resultine i

From Haddam Neck Debris Induced Fuel Failures i

I l

l I

During the third quarter of 1989, the Haddam Neck airborne releases of noble gas and iodine were significantly higher than normal. As a result, the Technical Specification limit l

for the quarterly beta air dose was exceeded. This Appendix provides information on tho l

cause of the increased releases, the resulting dose consequences as determined by both j

effluent models and environmental measurements, and corrective actions being evaluated to ensure future doses are minimized, j

l i

l Cause ofincreated Releases f

)

During the Cycle 15 operational run, Connecticut Yankee experienced a significant j

j number of fuel cladding failures. Fuelinspections during the refueling outage revealed l

that approximately 450 fuel rods had failed. The majority of the failures were caused by l

debris fretting. The debris was a machining by product from the thermal shield support l

system repairs which were performed during the previous refueling outage. Although l

the fuel failures occurred throughout Cycle 15 operation, the majority of the releases did l

not occur until after the shutdown for refueling. The debris induced failures were at the l

bottom of the fuel rod. Since stainless steel cladding is used at Haddam Neck, no secondary hydriding resulting in additional clad failures occurred. Hence, there was no l

flow path established to flush fission product radioactivity out of the failed rods, as would be expected in zircaloy clad fuel. The only realincrease from typical reactor coolant levels i

during the cycle was in longer lived noble gases, such as Xe 133 which had time to diffuse

)

i from the failure site at the bottom of the rod Reactor coolant 1131 levels remained at

]

l 0.02 uCi/gm for the cycle.

Prior to the September 2,1989 refueling shutdown, Haddam Neck had a continuous run j

of 461 days. Hence, there were no shutdowns to cause spikes in coolant activity. Noble j

gas releases during the first 8 months of the year were slightly higher than normal. Prior I

to the September 2,1989 shutdown the need to degasify more frequently resulted in less hold up time in the waste gas processing system and increased noble gas releases. With 1

j the shutdown and depressurization, significant quantities of noble gas and iodine were

]..

released from the failed rods. Reactor coolant 1 131 activity spiked to 11.4 uCi/gm.

)

3' As with all refueling shutdowns, the noble gases and lodine must be vented from the reactor head and steam generators. Venting is normally accomplished over the first A1

i several days of the outage. Because of the high levels of noble gas in the reactor vessel, the duration of venting was extended to three weeks to avoid exceeding Technical l

Specification instantaneous release limits and minimize off site doses. Weste gas system l

holdup was also maximized to further reduce dose consequences. Table 1 shows the i

curles released during September, most of which came from the venting process.

l Dose Conseevences i

Table 1 presents the maximum dose consequences resulting from the 1989 releases as calculated using the NRC's GASPAR code. As a result of the higher releases, the Safety i

Technical Specification Limit of 10 mrad for the quarterly beta air dose was exceeded for l

the third quarter. A 30 day Special Report was sent to the NRC on September 26,1989. A follow up report was submitted on February 14,1990. Table 1 shows that doses were j

maintained within the annual beta air dose limit of 20 mrad. All other doses were within l

their required limits.

The GASPAR calculated doses to the population within 50 miles were as follows:

l i

)

Whole Body -

4.2 person rem for 3rd qtr.,5.7 person rem for the year i

5.4 person rem for 3rd qtr.,7.0 person rem for the year

l Thyroid l

Skin 16.9 person rem for 3rd qtr.,24.5 person rem for the year l

Hence, the overall public dose consequence was insignificant.

l Environmental Sample Results and Dose Comparisons During September, extra vegetation and milk samples were collected to measure the l

effects from these increased releases. Also, TLDs were read more frequently in order to minimize natural background effects. Because of their large distance from the station, the milk samples lacked detectable 1131. However, the results of the vegetation samples taken close to the site boundary indicated positive levels of I 131 and are listed in Table 2.

Analyses performed on the routine weekly charcoal cartridges failed to indicate any statistically significant levels of I 131.

Table 2 also shows a comparison of the dose calculated flom environmental vegetation f

samples versus that calculated by the GASPAR model. The vegetation pathway was the 3

critical pathway in the GASPAR calculations. As can be seen, the results are in good l

agreement.

The only other media showing any effect from these releases was the environmental TLDs.

j T hese instruments monitorgamma air exposure at many areassurrounding the

[

l

stati:n As can be seen cn Tcble 3, thore is a measurable plant c ntributi:n, which is consistently positive for all areas nearby the plant. Although the error in these values is approximately 1 0.3 uR/hr (0.2 mrad), such a positive trend indicates that there is a measurable plant effect. Table 4 Shows a compariton of these TLD measurements with the doses calculated by the GASPAR model. In general, this comparison is fairly good, considering the errors involved in measuring such low doses and errors in meteorological averaging. Some error is also introduced by comparing 2 week TLD results with a background level based on a 4 week cycle. This error, as a result of fading would result in an uverestimate by the TLD of approximately 0.05 mrad. An exact comparison is not really possible in that the GASPAR results are really sector averaged in lieu of point specific. The G ASPAR code will also tend to underestimate the dose within the first half mile because of the use of the semi infinite cloud model for a partially elevated release. The maximum calculated GASPAR dose for September was 2.76 mrad at a location 0.3 mi. NNW, Although there was no TLD at this location, all of the TLD results were bounded by this value.

Corrective Actions in order to minimize the potential for similar releases in the future, the following corrective actions have been taken or are being evaluated:

First, an extensive fuelinspection program was performed. Over 3300 individual reinsert rods were inspected, All failed rods and, inspected rods with greater than 20% through.

wall defects were replaced.

Second, a flusing program will be conducted prior to start up to ensure debris from thermal shield work performed this outage or the previous outage will be removed.

Third, an augmented reactor coolant radiochemistry surveillance program to detect fuel failures during power operations has been developed. The augmented surveillance program consists of increased data evaluation of primary coolant activity, both noble gases and lodine. A license condition will require the increased monitoring along with appropriate action levels. Specific activity limits and plant actions will be determined prior to start up to ensure that the number of failed fuel rods during operations are kept below an act eptable number.

Fourth, additional actions, such as operational procedure changes and increased hold up of noble gases using charcoal are being considered in order to reduce release rates should similar levels of fuelfailure occur.

I

s Taide1 f

CY - 1989 AIRBORNE RELEASES AND CALCULATED OFF-SITE DOSES i

I seoble Gas sodme samme Air sets Air wheie medy skin Thymd Time Period neieaseKi) neicene Ki) pose (mrad pose (mrad none(aweed pose (awem) pose (ment i

january-Mardt 1,310

< MDA 0.22 0.61 0.13 0.37 0.0065 April-June 2,280 9.54E-6 0.61 1.87 0.36 1.13 0.025 I

i July 2,300

< MDA 0.77 2.34 0.46 1.41 0.25 l

August 2,300

< MDA 0.39 1.77 0.23 1.12 0.0045 l

September 7,700 1.29E-2 2.76 9.05 1.62 5.24 1.17 i

July-SeptemberTotal*

12,300 129E-2 3.50 11.90 2.06 7.04 1.02 I

October-December 1,230 1.43E-3 0.06 1.06 0.04 0.71 G.039 1989 Total 17,100 1.43E-2 4.39 15.44 2.59 9.25 1.09 i

Quarterly Limit 5

10 NA NA 7.5 Annual Limit 10 20 5

15 15 Totals of doses for the quarter are different than the sum of the monthly doses because of differences in location and meteorologicalaveraging.

A-4

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BROAD LEAF VEGETATION l

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j l-131 RESULTS l

DCi/am t

i

$lte lo andarv On Site On site Alone inlun > or ow Road Substation EAnal

{

l 9/7/89 0.082 2 0.045 0.170 2 0.028 I

s te l

9/13/89 0.073 1 0.030 0.037 1 0.027 i

t 9/19/89 0.018 3 0.016 0.010 1 0.013 1

i

(

l DOSE CALCULATIONS I

i Broad Leaf Vegetation Assume same as leafy vegetables j

0.06 pCl/g average for 3 weeks i

f e

z 3 werke s 6.72 x 10**

• a 0.61 mrrm toa chilcts thyroid 0.06pCVg 2 s

REMP AND GASPAR COMPARISONS i

DIQ @ GASPAR Masimum Lowtion, 8.64 E-8,

l DlQ @ AboveLowtion 6.5 E-8 REMP Result u 0.61 s 1.3 = 0,66 merm GASPAR Result = 1.17 mrrm :.76% l-131 = 0.88 mren I

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l Tame 3 j

i CY-SEPTEMBER 1989 FIELD TLD DATA l

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Contributio,s G a m ssee E w.

Direction Location (M) 800 ESE 1.1 (1)

Mouth of Duharge 7.162 21 681 6.4

.76 052 5

0.3 (2)

Haddam Park Rd.

7.402 10 6.7

.70 0.48 W5W 0.3 (3)

Haddam Jailhouse Rd.

7.632 03 7.1

.53 0.56 l

SW 1.8 (4)

Haddam Ranger Rd.

7.01 2 16 6.4

.61 0.42 l

NW 0.4 (5)

On-Site Injun Hollow 9.072 23 8.1

.97 0.66

{

NE 05 (6)

On-Site 5ubstation 8.61 2 02 8.0

.61 -

0.42 l

SE 1.8 (7)

Haddam 7.282 15 6.7

.58 039 l

WNW 3.2 (9)

Higganum 7.752 27 7.2

.55 037

)

NNW 2.8 (10) Hurd Park Rd.

8.841 17 8.4 44 030 SSW 0.1 (40) Intake 8.772 06 7.5 1.27 0.86 WNW 03 (41) Picnic Area 6.932 08 5.9 1.03 C.70 NW 0.1 (42) BoronWasteTanks 99.95 2

22 10.

90.0 61.3 *

• SE 1.0 (44) Horton Rd.

7.962 13 7.3

.66 0.45 1

j E

0.1 (45) WasteGasSphere 11.862 60 11.

.86 0.59 1

l SE O.2 (46) DuhargeCanal 8.602 11 7.9

.70 0.48 l

WNW 0.1 (47) Old Guard Shack 110.9263 7.5 103.4 70.4*

• g See 1989 data (average of March, May, July) j **

Greater than 90% of these results are from solid radwaste operations.

f j *** August 28 to September 25,1989 (1st set - August 28 to September 15,2nd set -September 15 to September 25,1989) i A-6

._________. _ - -._ __~..._ _ _._-..- - -._-_ _ _..._ _ _ __ _ ___._____,_ _ _

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t i

PL"JIT RELATED GAMMA DOSE 1

i i

l RD M

• GA$PM Direction Distance suarad ESE 1.1 052 032 i

r i

5 0.8 0.48 0.17

?

WSW 0.8 036 0.11 l

j SW 1.8 0.42 0.04 NW 0.4 0.66 0.63 l

NE 0.5 0.42 0.48 l

SE 1.8 039 0.15 WNW 3.2 037 0.03 3

NNW 2.8 030 0.07 i

SSW O.1 0.96 0.11 l

f WNW 03 0.70 0.10 i

i NW 0.1 0.75 j

1 SE 1.0 0.45 0.47 l

E 0.1 0.59 020***

j i

SE 02 0.48 0.58 i

i WNW 0.1 0.13 I

i Roentgen = 0.88 rad, hcnas to be conservative,we have assumed i

unity.

i TLD results influenced by radwaste operations, therefore comparison with effluent releases is imposseble.

• • • Dose at 0.8 miles E A-7

= -

_