ML20205G185
| ML20205G185 | |
| Person / Time | |
|---|---|
| Site: | Three Mile Island  |
| Issue date: | 10/25/1988 |
| From: | Baker G, Cooper W GENERAL PUBLIC UTILITIES CORP. |
| To: | |
| Shared Package | |
| ML20205G177 | List: |
| References | |
| OLA, NUDOCS 8810280206 | |
| Download: ML20205G185 (35) | |
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- gg ggtypeF5241 1988 crt UNITED STATES OF AMERICA BOW'ly NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of )
)
GPU NUCLEAR CORPORATION ) Docket No. 50-320-OLA
) (Disposal of Accident-(Three Mile Island Nuclear ) Generated Water)
Station, Unit 2) )
LICENSEE'S TESTIMONY OF DR. GARY G. BAKER AND WILLI AM J. COOPER ON DOSE ASSESSMENTS AND MICROORGANISMS
- (CONTENTIONS 2, 3 AND Sd) go%BM $$$R G
4 Q.1 Please state your name.
A.1 (GGB) Gary G. Baker.
(WJC) William J. Cooper.
Q.2 Dr. Baker, by whom are you employed, and what is your position?
A.2 (GGB) I am employed by GPU Nuclear Corporation as Man-ager, Environmental Controls, Three Mile Island Nuclear Station.
In these positions, I am responsible for the environmental moni-toring and evaluation of activitJes at THI.
Q.3 Please summarize your professional qualifications and experience relevant to this testimony.
A.3 (GGB) I have a B.S. degree in Biology and earned the M.S. and Ph.D. degrees in Environmental Microbiology. In 1978, I vas an Instructor in Biology and Microbiology at Indiana Univer-sity of Pennsylvania. In 1978 and 1979, I was an Environmental Scientist with Pennsylvania Electric Company, and in 1979 I began l
my employment with GPU Nuclear (and its predecessor) at TMI. As an Environmental Scientist from 1979 to 1981, I designed and im-plemented radiological monitoring programs. I was Radiological Programs Manager at TMI from 1981 to 1983, responsible for all phases of radiological environmental studies and monitoring pro-grams. In my current position at TMI, which I have held since 1983, my primary responsibility is to ensure that plant opera-tions are in compliance with all relevant regulatory require-ments. I am also currently an Instructor in Environmental o
. Microbiology at The Pennsylvania State University, Harrisburg Campus, where I teach both undergraduate and graduate courses. A complete statement of my professional qualifications is appended as Attachment 1 to this testimony.
Q.4 Mr. Cooper, by whom,are you employed, and what is your position?
A.4 (WJC) I am employed by GPU Nuclear Corporation as an Environmental Scientist in the Environmental Controls Department at the Three Mile Island Nuclear 5tation.
Q.5 Please summarize your professional qualifications and experience relevant to this testimony.
A.5 (WJC) I have a B.S. degree in Chemistry from the Uni-versity of Maryl'.nd, and I am a Certified Health Physicist with over ten years of health physics experience. From 1977 to 1980, I was a Health Physics Technician at The Johns Hopkins Universi-ty. I see 1980, I have been employed by GPUN (and its predeces-sor) in Health Physics positions at TMI. In my current position, which I have held since 1985, my responsibilities include the TMI Radiological Environmental Monitoring Program, and the develop-ment, maintenance and operation of routine effluent off-site dose calculational codes. A complete statement of my professional qualifications is appended as Attachment 2 to this testimony.
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. Q.6 What is the purpose of this testimony?
A.6 (GGB, WJC) We vill address the issues remaining on the radiological dose estimates off site for.the GPUN proposal to evaporate the TMI-2 A cident-Generated Water ("AGW") and for the alternative raised by the Joint' Intervenors, involving on-site storage followed by disposal. In parcicular, in response to Con-tention 2, we vill compare the dose consequences of the propossi and the alternative. In response to Contention 5d, we vill explain hov our dose modeling methodology takes into account the effects of the tritium which vill be released during evaporation. (
l (GGB) I will also respond to Joint Intervenors' Material ,
t Statement of Fact No. 9, under Contention 3, by describing why !
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any microorganisms present in the atmospheric release are of no '
concern. ;
Q.7 How is your testimony organized?
A.7 (GGB, WJC) We vill first describe the calculational i method used for dose essessments at TMI. Second, we vill present l the GPUN estimates of the doses to the maximally exposed hypo- I a
thetical off-site person and to the off-site population, from the [
evaporation of the AGW. Third, vc vill assess the dose conse-quences of Joint Intervenors' alternative of further storage fol- <
loved by disposal, and compare it with GPUN's evaporation prepos- l al.
Finally, I will address the issue of microorganisms ;
(GGB) in the atmospheric release from evaporation.
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. Q.8 Please describe your dose assessment methodology.
A.8 (GGS) The primary onvironmental dose assessment com- l puter code used by GPUN Environmental Controls is ths Meteoro),og-ical Information and Ocse Assessment System (MIDAS). This code, which is used for quarterly and semi-annual dose assessments sub-l
.nitted to the NRC Vith TMI-l a'nd THI-2 effluent reports e is ;
1 l designed to allow environnental dose assessment for chronic and j acute exposures. The routine release portion of the model pro-l vides the dose, assessment required to demonstrate compliance with '
10 C.F.R. Part 50, Appendix I guidelines for plant releases, is based on NRC Regulatory Guide 1.109, and uses atmospheric dispor-sion calculations based on the Pasquill-Gifford method presented in Regulatory Guide 1.111. MIDAS uses hourly averages of on-site meteorological data te caleviate an integrated dispersion for the period of interest. It integrates the dispersion over each hour into each rf sixteen sectors at ten distances. !
l The dispersion modeling derives the average airborne concen-I tration, deposition rate from the plume, and ground plane concen- !
tration of each radionuclide in each sector as a function of .
l' time. The dose due to direct exposure to radioactive material in ,
f
. the plume and deposited on the ground is determined by MIDAS di-4 t i rectly from these functions, using published conversion factors 1
- such as those in Tables E-6 and B-1 of Regulatory Guide 1.109.
The MIDAS code has been reviewed and approved by the NRC Staff. It has also been reviewed by an Atomic Safety and
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. Licensing Board, in the TMt-Restart proceeding in WP ch TMIA vas ,
a party, and was found to be an acceptable code for assessing at-mospheric dispersion and environmental dose. ,
i Q.9 What are some of the site-specific features used by the MIDAS code?
A.9 (WJC) The code employs numerous site specific files in order to provide a realistic model of the releases. For example, for atmospheric releases, the Unit 2 portion of the model consid-ers the following:
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- a. Two Jeparate release points with plant-specific charac-teristics including height of the vent stacks, diameter of the vents, linear flow rate from the vents, and building dimensions for vake effects.
! b. Three different methods of assessing plume rise.
Plumes can be treated as ground level, elevated, or !
vake split. The wake split method is normally used on the station vent and the gcound methed is normally used on other release points. Wake spli; treatment causes i the model to assess the degree of jet plume rise with i each release condition of meteorology and ventilation flov. The model then treats a fraction of the release as an elevated release and the remainder as a ground release to approximate the amount of the plume which is ;
l entrained by the building vake effect. The evaporator i l
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. was censervatively treated as a ground release, which generally produces the highest calculated doses because of lover mixing prior to ground contact of the plume,
- c. Seven environmental exposure pathways. The pathways included in the model are (1) human inhalation in the plume, (2) direct radiation to humans from the plume, (3) direct radi.ation to humans from radioactive materi-al deposited on the ground from the plume, (4) inges-tion by humans of vegetation grown on soil with ra-dionuclides in and on the soil which have been deposited from the plume, (5) ingestion by humans of cov milk from animals which have consumed vegetation grown on soil which contains radionuclides deposited from the plume, (6) ingestion by humans of goat milk from animals which have consumed vegetation from soil which contains radionuclides deposited from the plume, and (7) ingestion by humans of meat from animals which have consumed vegetation grown in soil with plume de-posited radionuclides,
- d. Actual residence locations. The actual locations of residences or clusters of residences in the vicinity of the plant in each of the standard sixteen compass sec-tors are included in order to have actual locations of residents for the direct plume exposure, direct plume
. inhalation, and direct soil deposition exposure path-vays,
- e. Actual garden locations. The actual lo:ation of the nearest garden in each of the sixteen standard compass sectors are included in the model. Each resident fur-ther from the plant thar, the nearest garden is assumed to have e garden also. This allows an assessment of the vegetation ingestion dose to humans based on actual ,
land use around the plant. The maximally exposed indi- ;
j vidual is assumed to reside in the location of highest plume inhalation and direct exposure and to eat food-stuffs from the highest garden, even if that garden and the maximally-exposed individual's residence are not in
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the same location.
- f. Actual milk animal locations. The locations of all known animals used for milk for human consumption with-in five miles of the plant are included, broken down into sixteen compass sectors. This allows assessment of the cow and goat milk pathways based on the actual 1
land use characteristics around the plant. The maxi- l l mally exposed individual is assumed to drink cow milk l
and goat milk frem the highest locations, even if the individual does not actually reside in those locations.
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. g. Actual meat animals. Locations of actual known meat animals within five miles of the plant are included to provide an assessment of the meat pathway dose based on actual land use around the plant. The maximally ex-posed individual therefore lives at the location of highest plume and deposition direct exposure and inhalation exposure, while eating meat, milk, and vege-tation from the highest locations for those pathways even if the-j are not co-located.
- h. Actual distances to the site boundary and actual ter- '
! rain heights in the vicinity of the plant. The use of the actual site boundary distance specifies where to begin assessment of the plume exposures. The inclusion of terrain heights allows a better estimate of the dep-
) osition of radionuclides on :he soil, since deposition i
is in part dependent on ground contact of the plume. ,
, Q.10 How do you use the code to calculate ingestion and inhalation doses? ,
A.10 (WJC) Numerous parameters are used to estimate the transfer of radionuclides through the environment. Since some of the pathways involve multiple environmental media and trophic levels, estimates of the concentrations in each trophic level are required to adequately estimate the environmental dose from all of the pathways. For example, for the cow milk pathway, the l
t 1 ,
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1
model must first estimate the dispersion and deposition of the particulate radioactive material in the effluents onto the soil.
It then uses transfer coefficients from NRC Regulatory Guide i
1.109 to estimate the concentration of radionuclides in vegeta-tion based on the amount in the soil. Food consumption rates specific to cows are then appi' led to the vegetation to estimate the total amount of each radionuclide the milk animal consumes in a day, and transfer factors are applied to determine the concen-
] tration of the radionuclides in the milk. The consumption rates ,
(usage factors) and transfer factor used by MIDAS are those i
contained in Regulator' Guide 1.109. These are generally experi-mentally derived factors selected by the NRC staff following a review of the applicable literature.
l The MIDAS code estimates the quantity of each radionuclide ingested or inhaled by members of the public. To provide greater j accuracy, age specific parameters are used to specify t!.e inges-tion of various foodstuffs and ' eater and inhalation rates. The offsite population is modelled by specifying four different age groups -- infants, children, teenagers, and adults -- each with specific ingestion and inhalation parameters. Ingestion and
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inhalation factors for each age group are specified in table E-5 in Regulatory Guide 1.109 for the maximally exposed individual.
These are based on actual usage studies by the Department of Ag-riculture as well as on the "Reference Man" study in Internation-al Commission on Radiological Protection (ICRP) Publication 23.
When the ingestion and inhalation quantities have been cal-culated, conversion factors between the quantity of each nuclide ingested or inhaled und the 50-year integrated dose committment are applied. These factors (Dose Conversion Factors or DCFs),
which are specific for each age group and radionuclide, represent an estimate of the dose per unit of radioactivity (i.e., mrem per picoeurie). The factors are provided in numerous publications from the NRC and other sources. The primary sources in use for chronic (routine release) exposures are Regulatory Guide 1.109 and NUREG-0172, which are in turn based on ICRP publications, including ICRP Publication 2, ICRP Publication 10, and ICRP Pub-lication 23. The DCFs in Regulatory Guide 1.109 and NUREG-0172 have been calculated based on intake route (i.e., ssparately for inhalation and ingestion), age group, and isotope, using aca spe-cific characteristics of body and organ site as well as biologi-chl half lives and differences in physiology of the different ages (such as GI/LLI transit times). Biological half lives (the effective residence time of radionuclides in the body) are an in-tegral part of the derivation of the DCFs, as is the Quality Fac-tor of the radiation from each radionuclide. The Quality Factor (derived from the Relative Biological Effectiveness -- RBE) is a measure of the biological impact of radiation from a particular radionuclide as compared against a reference gamma source. Thus, the Dose Conversion Factors take into account the particular in-teraction of each radionuclide with the human body and permit
. calculation of a dose equivalent that reasonably reflects the total relative effect.
- The dose calculated by MIDAS is a 50-year dose commitment.
It is essentially an integration of the total dose possible to an individual following ingestion, inhalation, or exposure to a ra-dionuclide for the following 50 years. This accounts for the initial intake, the fraction of initial intake retained, the fraction of the initial intake deposited in the body tissues, and the removal of the deposited activity by biological removal and radioactive decay. In most cases, the total esidence time of the radionuclide in the body is much smaller than the 50-year in-tegration time, and most of the calculated dose is delivered in a much shorter time.
Q.11 This hearing uniquely focuses upon the amount and ef-fects of the tritium to be released during evaporation of the AGW. Hov have you accounted for tritium in your dose assessment modeling?
A.ll (WJC) There is considerable discussion in the litera-
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ture regarding the Quality Factor for tritiun. radiation which should be used. ICRP Publication 2, on which the DCFs are based, i
used a factor of 1.7 as the Quality Factor for trit.um's lov en-ergy beta radiation. Factors ranging from one to three are com-mon in the literature, and recerit National Council on Ra-diological Protection and Measurements (NCRP) publications recom-mend a Quality Factor of one. The use of a Quality Factor of
. 1.7, as GPUN does, vill produce a calculated dose which is simply a factor of 1.7 times that computed using a Quality Factor of one.
Tritium is also a special case in the calculation of off- (
site doses because of the ability of the skin to freely exchange ;
vater with the atmosphere. Typically, about one-half of the tritium intake from exposure to atmospheric tritiated water (KTC), which is the form of tritium in the accident generated water, is through absorption through the skin. The total intake of tritium used in the model for airborne tritium is, therefore, the sum of the amount innaled and the amount absorbed through the skin. This additional intake of tritium through the akin is ac- l counted for in the Dose Conversion Factor for inhalation.
In the case of tritium, the biological half life of the vater fraction is on the orde: of 10 days. Additional compart-ments for tritium with half lives as long as about 130 days and 250 days also exist, but these include only a small fraction !
l (less than 10%) of the tritium in the body and do not in fact i i
contribute significantly to the actual dose commitment. NCRP l Publication 62 explains that the dose from the three compartment model for tritium, (which accounts for the fractions of tritiun in the body which exist as free water, labile-freely exchangeable organic, and tightly bound organic hydrogen) is only about four percent higher than that from the free water only. In addition, the NCRP 63 indicates that the dose to the cell nucleus L
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, associated with the chromosomal structurea is trivial compared to ,
- that from the tritiated water in the cell. Thus the majority of the dose from tritium is incurred within a few veeks following the exposure from the tritiun existing as free water in the body.
The Dose Conversion factor for tritium used by GPUN's model em- [
ploys the effective half life for tritiated water recommended in 1
!CRP Publication 10. The dose factors are designed for use for chronic (i.e., slov uptake) exposures from releases from nuclear i facilities. These factors p,rovide a committed dose, integrated [
J l over the lifetime of the individual.
t
) Q.12 What has GPUN calculated to be the off-site doses from 1 !
the proposed evaporation of the AGW? ;
L i A.12 (GGB) The radiological consequences to the public j from the controlled, atmospheric release of the evaporated AGW j have been determined by estimating the dose to both the maximally F exposed hypothetical off-site person and to the total exposed population. The dose to the maximally exposed hypothetical off- j site person is a conservative (over-estimated) assessment of the f exposure to a member of the public, as required by Appendix ! to f 10 C.F.R. Part 50, using Regulatory Guide 1.109 dose methodology. l
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The maximally exposed hypothetical individual is assumed to be a j person in the maximum inhalation le1ation who consumes meat, veg- !
I etables and milk from each of the other maximum dose pathway lo- !
cations. The estimated dose to the total exposed population is a ;
i more representative essessment of the radiological consequences ;
resulting from evaporation of the AGW, !
(
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. The MIDAS code was used to calculate the estimated doses to ,
I the maximally exposed hypothetical off-site person for the dura-tion of the evaporation process (taking ,into account, as well, the extent of processing / reprocessing of the AGW). The dose to the bone is estimated to be 0.4 mrem, while the total body dose is estimated to be 1.3 mrem (1.2 mrem of which is from tritium).
These doses, which are not annual doses but rather estimates for the duration of the evaporation process, still are well below the annual guideline of 15 mrem given in Appendix I to 10 C.F.R. Part 50, for exposure from airborne releases.
MIDAS was again utili:ed to estimate the dose to the popula-tion. In addition to estimating the inhalation and ingestion doses to the 2.2 million people within a 50-mile radius of THI-2, t i
the code also estimates the ingestion done to an additional 13 million people assumed to be fed agricultural produce exported from within the 50-mile radius. The total exposure to the popu-lation from evaporation of the AGW is estimated to be 2.4 person-rem to the bone, and 12 person-rem to the total body. For sim-plicity, in calculating an average ve have applied the total population dose (to 15.2 million) to the 2.2 million people liv-ing within 50 miles. This yields a conservative (i.e., upper b6und) average exposure to a member of the 50-mile population of 0 C i em to the bone and 0.005 mrem to the total body. Since sn; talotation process vill take mere than one year, the annual population doses are less than the values ! just reported.
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As I explained earlier, the conservatisms built into the calculations performed by GPUN provide an upper-bound estimate of the environmental dose from AGW evaporation. The actual doses are likely to be much smaller than those calculated.
Q.13 Are these doses fro;m the evaporation proposal signifi-cant in your view?
A.13 (GGB) No. The insignificance of these doses is evi-dent. The 0.4 mrem dose calculated to be delivered to the bone is actually incurred over the life of the maximally exposed indi-vidual, and not in the one to two year period of the evaporation process. The actual average dose rate from the strontium to the maximally exposed person vould be less than 0.01 mrem per year.
Compared to this 0.01 mrem estimated annual bone dose from stron-tium and the 1.2 mrem total tritium dose that the maximally ex-posed individual might receive from the evaporation of the AGW, the average individual in the TMI area vill receive 300 mrem per year from natural radiation (about 70 mrem from direct radiation from the soil and cosmic rays, 30 mrem from internal natural ra-dioactivity and weapons fallout and 200 mrem whole body equiva-lent from radon daughters) each year. The maximum individual organ dose to the bone is less than 0.003% of the naturally oc-curring whole body radiation the average member of the population would receive during the 50-year integration period. The whole body dose from tritium is about 0.01% of the natural whole body dose.
. The variability of individual doses is quite large. Radon doses alone can vary by factors of ten depending on the individ-i ual's home conditions. Direct radiation from cosmic and terres-i trial sourtas can also vary. Differences in the local geology 4
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can easily change the local terrestrial dose rate by a factor of two, as is routinely seen in the direct radiation monitoring by TLD (thermoluminescent dosimeter) conducted by GPUN around Three Mile Island. Normal environmental exposure levels from direct ;
radiation of 40 to 90 mrem per year are common, depending on the location monitored. The additional dose to the maximally 1 sed
, individual from evaporation is far below the normal environmental .
dose variability, and the additional dose to the average off-site
, individual is thousands of times smaller. !
I Q.14 Have you considered the radiological consequences of Joint Intervencrs' alternative of AGW storage followed by dispos-al?
A.14 (GGB) Yes. The apparent benefit of this alternative
! is that i t provides time for the radionuclides in the AGW to decay further. Over,a 30-year period, the strontium at.d cesium curie content would decrease by approximately a factor of two.
) The tritium content vould decrease by a factor of about six over the same time period. However, based on the off-site dose asJessment performed by GPUN, this decrease in tritium would not have a significant effect on the dose assessment < This is be-cause the doses are already so very lov that such a decrease in the source term is not meaningful.
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, Q.15 An identified material issue of fact for this hearing is whether utrontium or tritium is the critical radioisotope.
Please address this issue.
A.15 (GGB) Strontium-90, in contrast to tritium, has a very long biological half life, on the order of 15 years, and is not eliminated from the body completely even after the 50-year integratu , clod. In addition, strontium-90 has a higher ener-gy beta, two betas per decay (including yttrium-90), and concen- 1 trates in a single organ (bone). As a result, if the atrontium-90 concentration in AGW vere not reduced by evapora- !
I tion, the strontium would dominate cose calculations. With a i decontaminar. ion factor of 1,000 achieved by the evaporator, how-ever, tritium is the radionuclide that contributes the most to calculated doses -- 1.2 of the 1.3 mrem total body dose to the ma::imally exposed individual for immediate evaporation.
Q.16 On page 20 of its August 25. 1988 Memorandum and Order, the Licensing Board discussed the issue of whether stron-tium or tritium would be dominant after 30 years of additional storage of the AGW. The Board observes that "(i]f evaporation
. were the taethod of disposal at that time, the strontium would not be releasad, but would be concentrated in the evaporator bot-f tems." Is that observation correct?
A.16 (GGH) Almost. As Mr. Buchanan established in his of-fidavit earlier in this case on Contention 4, the evaporator sys-tem will achieve a decontamination factor of at least 1,000
(except for tritium, all of which will be released). Consequent-ly, at least 99.9% of the strontium-90 in the processed AGW, whether now or in 30 years, will be concentrated in the evaporator bottoms. It is assumed, however, that 0.1% vill carry over and be released to the atmosphere. This 0.1% of the avail-able strontium-90 is utilized'in our dose calculations.
Q.17 Have you quantitatively assessed what the doses would be if the AGW vere evaporated after 30 years of additional stor-age?
A.17 (GGB) It is not possible to estimate, with any rea-sonable degree of accuracy, the potential off-site dose commit-ment f,r evaporation of the AGW following 30 years of additional decay. As I explained earlier, the MIDAS code utilized for envi-ronmental dose assessments is based upon current land use and population distribution. Year-to-year changes in residences and land use are incorporated into these calculational models, and are based upon extensive GPUN surveys -- more extensive than those required by the TMI-2 license Technical Specifications.
Since the dose is dependent upon the maximum pathways -- includ-ing the maximum garden, cow milk and goat milk pathways -- any change in the land use may significantly affect the dose commit-ment to the maximally exposed individual.
If one made the assumption that all off-site parameters of land use and population distribution remained exactly the same aa they are in 1988, then 30 years of decay would affect the doses to the maximally exposed off-site person and to the population.
The bone dose could be expected to be reduced by a factor of two as a result of the passage of about one half life of strontium-90. The whole body dose to the maximum individual would be reduced from the 1.3 mrem from all radionuclides (1.2 mrem of which is from tritium) to about 0.3 mrem, a reduction to about one-fourth. The maximally exposed hypothetical off-site person would receive a bone dose of 0.2 mrem over the individ-ual's life (instead of 0.4 mrem), which represents an average annual dose of less than 0.005 mrem (instead of less than 0.01 mrem from evaporation now). Similarly, after 30 years the aver-age exposure to the bone to a member of the population would be one-half of the currently projected 0.001 mrem, and the whole body dose would be one-fourth of the currently projected 0.005 mrem.
In reality, changes in land use could actually result in dose projections 30 years from now which are higher than current estimates -- that is, the effects of decay could easily be offset by other factors. In my opinion, then, it is clearly not prudent to postpone AGW disp 7 sal for the mere hope that off-site doses will be reduced from their already insignificant values to even lower on(s.
Q.18 Dr. Baker, as an experienced environmental scientist, how do you compare the evaporation proposal with Joint Interve-t nors' alternative of further storage followed by disposal of the i
l AGW7 l
, A.18 (GGB) It appears to me that the choice hinges upon an assessment of the dose savings achieved from radiological decay during a further storage period, and the, cost of the further storage. I could not endorse the Joint Intervenors' alte.aative for any further cost, let alone'for the ignificant costs presented in Mr. Buchanan's testimony. I start from the posi- :
tion, which I have explained, that the off-site doses which are ;
I conservatively projected to result from the evaporation process are by any standard miniscule and insignificant. It would be to-tally unjustified to store this water for 30 years in the hope that land usage vill not change and the doses would be one-half of their already extremely lov levels. I must emphasize that these dose levels are so low that they are within the range of
- uncertainty of state-of-the-art dose assessment methodology and -
radiological monitoring. Half of nothing is still nothing. From an environmental cost / benefit standpoint, the evaporation propos-
- al is the clearly preferred solution for disposal of the AGW.
Q.19 At page 36 of its August 25, 1988 Memorandum and order, the Licensing Board held that Joint Intervenors' Material
! Statement of Fact No. 9, under Contention 3, put into contest the evaluation of microorganisms in the AGW. In their Statement, the l Joint Intervenors cite an NRC Staff discovery response for the proposition that water boiling at 212*F would kill the microorga-l nisms. Yet, according to Joint Intervenors, the evaporator will l
l operate at a temperature of 131*F. Therefore, Joint Intervenors 1
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conclude that a quantity of the microorganisms will be contained in water droplets to be released to the environment, and their release must be evaluated because of possible pathogen problems.
Dr. Baker, have you evaluated this concern?
A.19 (GGB) Yes. The microorganisms associated with the AGW have been studied and dete~rmined to be typical environmental microbes. They are not considered to be primary pathogens and do not pose a health threat to the workers or the general popula-tion. Further, there are several factors whl:h virtually pre-clude pathogen survival in the environment.
i First, the microorganisms in the AGW can be traced to three principal sources: the Susquehanna River, hydraulic fluid from defueling tools, and the general airborne environment. None of these sources yield a primary pathogenic population. Haman pathogenic microorganisms are transmitted principally from fecal contamination and/or vector mediated transfer. These microorga-i nisms are very fastidious relative to their nutritional and envi-ronmental needs. Consequently, they do not survive in the gener-al environment outside the human body, 1
- Second, studies conducted on aerosols emitted from cooling towers supplied with secondary sewage effluent confirm that air-j borne transmission of pathogens is not a significant threat to l either the workers at the plants or to the surrounding popula-tions. (Adams et. al., 1978.)
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Third, natural biocidal activity, such as the lethal effects of ultraviolet light and dessication, prevent the long-term sur- ;
vival and growth of most microorganisms. Here, the salt-concentrating effects of the evaporative process (i.e., boron) will in itself be blocidal. -
Finally, when they cite the Preliminary System Description (Feb. 26, 1988) for an evaporator operating temperature of 131*F, Joint Intervenors are referring only to the evaporator section, which operates under a vacuum. As that document states in sever-al places, the vaporizer section will heat the distillate to ap-proximately 240*F. This temperature is lethal to virtually all microorganisms. Pathogenic microorganisms are susceptible to the lethal effects of heat above normal body temperature. The micro-organisms that can withstand temperatures at this level are not pathogenic to humans, i
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References NUREG-0172, "Age-Specific Radiation Dose Commitment Factors For a One Year Chronic Intake," G. R. Hoenes, J. K. Saldat (November 1977).
Regulatory Gui.de 1.109, "Calculations Of Annual Doses To Man From Routine Releases of Reactor Effluents For The Purpose Of Evaluating Compliance With 10 C.F.R. Part 50, Appendix I, Rev. 1 (October 1977).
Regulatory Guide 1.111, "Methods For Estimating Atmospheric Transplant And Dispersion Of Gaseous Effluents In Routine Re-i leases From Light-Water-Cooled Reactors," Rev. 1 (July 1977).
ICRP Publicatior 2, "Report Of Committee II On Permissible Dose For Internal Radiation" (1959).
ICRP Publication 10, "Evaluation Of Radiation Doses To Body Tis-sues From Internal Contamination Due To Occupational Exposure" (December 1986).
4 ICRP Publication 23, "Reference Man: Anatomical, Physiological And Metabolic Characteristics (April 1975).
NCRP Report No. 62, "Tritium In The Environment," (March 3, 1979).
NCRP Report No. 63, "Tritium And Other Radionuclide Labeled Or-ganic Compounds Incorporated In Generic Materials," (March 30, 1979).
Adams, A. P., Garbett, M., Rees, H. B., and Lewis, B. G., "Bacte-rial Aerosals from Cooling Towers," Journal, Water Pollution control Federation, pp. 2362-69 (October 1978).
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A";TACRMENT 1 GARY G. BAKER, PH.D.
PROFESSIONAL BACXGROUND 1983 to Manacer of Environmental Controls-Three Mile Present Island GPU NUCLEAR, Middletown, PA Primary responsibility is to ensure that plant operations are in compliance with all relevant regulatory agencies. Also coordinate planning for the dismantlement of Saxton Nuclear Experimental Facility.
Environmental Controls Operations... Staffing... Budget Planning / Implementation... Policy Design /Reviev...Public Relations...Offsite Emergency Plan Response... Environmental / Radiological Surveys Programs...
1981 to Radiolecical Pecorams Manacer-Three Mile 1983 Island GPU NUCLEAR, Midd16*.own, PA Responsible for all pncses of radiological environmental studies and monitoring programs. Contract l Administration... Professional j
Testimony... Environmental Assessment t Coordinator...Public Relations... Management i Interface...
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1979 to Environmental Scientist It-Three Mile island 1981 GPU NUCLEAR, Middletown, PA Designed and implemented radiological monitoring programs. Evaluate Exisiting Systems... Evaluate Data...Honitor Commercial Laboratories... Management Reports...
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1978 to Environmental Scientist III-Pennsylvania
. 1979 Electric Active in all aspects of biological stuides and monitoring program for ten coal fired and two hydroelectric facilities. Program Evaluation... Design / Conduct Studies... Interpret / Report Technical Data...
1978 Instructor INDIANA UNIVERSITY OF PENNSYLVANIA, Indiana, PA ,
. Taught General Biology and Microbiology at an undergraduate level.
Other I served as a consultant to the educational and business community in Central Pennsylvania addressing microbiology problems and graduate student programs.
EDUCATION 1978 Ph.D.-Environmental Microbiolqay WEST VIRGINIA UNIVERSITY, Morgantown, WV 1975 M.S.-Environmental Microbioloav WEST VIRGINIA UNIVERSITY, Morgantown, WV 1971 B.S.-Biolocy MORRIS HARVEY COLLEGE, Charlestown, WV ,
1966 to Bioloav 4
1968 UNIVERSITY OF UTAH, Salt Lake City, UT i
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ATTACHMENT 2
- RESUME William J. Cospor
'GPU Nuclear Corp Three Mile Island Nuclear Station PO Box 480 Middletown Fa 17057 Education BS Chemistry 1977 University of Maryland, College Park Maryland Additional courses:
1986 Health Physics Summer School - External Dosimetry 1987 contracted class - Internal Dcmingtry/ICR730 1983/1984 Dickinson College, Carlisic - Health Physics, 2 semesters 1980 Penn State University - Radiation Shielding 1 semester 1978 The Johns Hopkins University - Radiation , Biology (audit)
Experiences 1985 to present - Environmental Scientist, GPU Environmental Controls operate and control the TMI Radiological Invironmental Monitoring Program (REMP) including all phases of design, development and operation of existing and new sagling regimes. Operate and maintain the environmental Thermoluminescent dosimetry program.
Support the TMI Emergency plan by developing and operating emergency offsite dose calculational meuods and computer codes.
maintain, and operate routine affluent offslte dose Develop, calculat ion codes to provide assessment of dose committmants from normal plant effluents and to provida a priori dose estimates for licensing documents.
1 1983 to 1985 - Radiological Engineer, GPU Radiological controls.
Provide engineering support and review of inplant work plans to ensure work conducted in radiologically controlled areas is '
"ALARA". Review individual tasks as well as system designs for
- incorporation of features to minimize e g ooure to radiation l
and radioactive materials. Was primary GPO Radiological Engineer ,
I for the defueling system design et TM2-2. Also responsible for l internal dose assessment for workers, shielding design, and the l l developuent of the policy to provide access into the TMI-2 I reactor building without respiratory protection. Support the l euergency plan by performing offaite dose assessment, and controlling the in-plant radiological personnel.
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to 1983 - Rcdiological 1981 Controls. Centrolo ForCOan, GPU Radiologicci Supervise and control up to about 30 in-plant radiological controls technicians. Review and approve all in plant work in radiologically controlled areas. Provide approve protective guidance for workers on exposure controls, measures (eg clothing). Supprt the emergency plan by performing offsite dose assessment until arrival of the Rad. Engineer and i inplant radiological control and technician supervision durinq !
emergencies. Temporary duty in Unit-1 to support inplant radiological controls during the OTSG kinetic expansion repair 1980 to 1981 - Radiological controls Technician, GPU Radiological controls. Provide inplant support duriM routine and emergency conditions to work crews in radiologically controlled areas.
Conduct surveys and perform ef fluent sampling. Supervise other technicians in the absence of the foreman. Performed first post-accident surveys of the TMI-2 reactor vessel head, refueling canal, and polar crane.
1977 to 1980 - health Physics Technician, The Johns Hopkins University Homewood Campus, 3400 North Charles Street, Baltimore, Maryland Was only Health Physic technician on Homewood Campus, with several dozen indipendent laboratories using radioisotope tracers in biological and chemical research as well as sealed sources, irradiators, and diffraction and fluorescence x-ray machines, in geol m , materials science, and physics research.
The campus also had MEV energy Van-de Graff accelerators which were not in use at the time. Responsible for external and internal dosimetry, effluent control, vasta packaging and shipping, periodic laboratory surveys and inspections to enforce license compliance for sevreral dozen authorized users on the licenses and as many as 400 individual workers. Also assisted users with radioisotope conuting problems and developed the iodine-125, tritium, and phosphorus-32 bioassay program.
Assisted professor of biolog in his bioluminescent organism (photobiology) research with spectral analysis, phytoplankton culture media, developed radioactive single photon visible light spectral calibration sources. Began research program to attempt to demonstrate non-lethal biolgical ef fect of low-level radiation by irradiation of bioluminescent organisms (not completed at time of resignation).
Paperst Angular and absolute response to wanon-133 of a Thermolum;mescent Dosimeter used for Environmental Monitoring (in preparation)
A Simpified Air Tritium Sampler (in preparation)
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. Professional societies:
Plenary Member - Health Phyr,1cs Society Member - American Nuclear Society Member - Susquehanna Valley Chapter of the Health Physics Society Member - Central Pennsylvania Chapter of the American Nuclear Society and 1988-1989 treasurer Member - American Academy of Health Physics Professional certifications:
Certified Health Physicist - Achieved "Comprehensive" certification by the American Board of Health Physics in 1985 ,
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indivi. dual dose for the all 2.2 million people living within a 50 mile radius of Three Mile Island. This yields a population or collective dose of 3.21 person-rem, as estimated by the NRC.
The doses as calculated by GPUN are elightly higher, and therefore the approach is more conservative. GPUN calculated that the hypothetical maximally exposed individual would receive 1.3 mrem to the total body and 0.4 mrem to the bone, which when combined produces an offective dose equivalent of 1.4 mrem to the maximally exposed individual. The average exposure for the 2.2 million population within a 50 mile radius is estimated to be 0.005 mrem per individual and the total population or collective dose is rounded up to about 12 person-rem (effective dose ec .va-lent).
Q.104. Are these doses of significance in causing any potential health effects in any exposed populations?
A.104. (JAA) No, the doses are extremely small. They are in fact in the range normally considered de minimis or presenting negligible risk to human health. An illustration of how ex-cremely small these dosee are is ob:ained by comparing them with the radiat2cn doses an individual receives from natural and nan-made sources r>f radiation in everyday lafe. This comparison is shown in the following table.
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Radiation Doses From Natural and Man-Made Sources National average background in U.S. (whole body) 300 mrem /yr*
Additional whole body dose from living in a brick house instead of a wooden house (whole body) 20 mrem /yr**
Round trip flight from New York City te Los Angeles in a large commercial jet (whole body) 1.9 mrem **
Diagnostic chest x-rays (series of 2-3 x-rays to the thorax) (chest) 40 mrem **
Dental x-ray (per exposure) to the cum and mouth (month) 2.cs mrem **
Exposure to color television set (whole body) 1 mrem /yr**
Exposure to tritium watch dial (whole body) 0.5 mrem /yr** l
- NCRP Report No. 93.
- UNSCEAR 1977, at 13, 51, 83, 99, 310, 319.
As one can see, the dose to the hypothetical maximally exposed individual from the evaporation of AGW would be less than ena percent of the done an individar.1 we.uld reco Ave from natural backcround radiation each yenr. It !.s less than 10 porcent ef an additional dote a person would receive from living in a brick ,
building each year, and is comparable to the whole body dose an average individual in the general population receives from watching color television each year. The dose to the average individual is many hundreds of times less and thus de minimis.
P Q.105. Applying the risk estimates above, what is the prob-ability that members of the public will develop a fatal cancer induced by exposure to the tritium from the evaporated AGW?
A.105. (JIF) Applying current total cancer mortality risk
~4 estimates (1 to 2 x 10 / rem) to GPUN's and the NRC's estimates of nopulation dose, the estimates of the total number of excess cancer deaths among the 2.2 million people living within 50 miles of TMI-2 range from 0.0003 to 0.0024. This risk can be restated as an upper-limit of less than one chance in 400 for the possible occurrence of a single fatal cancer among the 2.2 million people.
The upper limit probability of a fatal cancer for the maximally expvced individual is less than one chance in 5 million using the NRC's calculated dose and less than one chance in 2.5 million using GPUN's calculated dose. For all practical purposes, while an excess value can be estimated based on modelling and mathemat-ics, in fact no excess fatal cancers will result from the tritium and the other radionuclides during the evaporation process.
These risk estimates are based on the TCRP (197") current values and do not take into account any new data or revisions of the desimetry of the atomic bombings. The estimates are also based on the 1980 BEIR III Report. The estimatae may need to be revised upward armewhat pending revision of the Japanese atomic bomb dosimetry and new statistical procedures presently being applied to the new data by the 1988 UNSCEAR and 1988 BEIR V Com-mittees. It to roughly estimated that the risk coefficient may
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be increased overall by a factor of about 1.5 to 1.7, but can be much less, depending on dose, age at the time of exposure, sex, cancer organ or site, and a number of other factors. In some in-stances, these risk estimates will not be revised upward at all.
Q.106. Will this have any significant effect on the poten-tial excess cancer risk associated with evaporation of the AGW?
A.106. (JIF) No. In simple arithmetic terms, it could raise the estimates of the total number from a range of about 0.0003 to 0.0024 up to about 0.00045 to 0.0036. This would have no practical consideration for concern. The risk remains de minimis.
Q.107. What is the spontaneous incidence of fatal cancer in a population of 2.2 million persons in the absence of any radia-tion exposure above backgrounc't levels?
A.lO7. (JIF) The cancer mortality rate in the United States is about 20%, i.e.. 20% of all persons in a general popu-lation wsli die of a fatal cancer. In a population of 2.2 mil-lion persons, it is estimated about 440,000 persons will eventu-ally die of cancer.
Q 108. Wh t.t is the rick of potential genetic i?,1 health re-aulting from the evaporation of the ACW7 A.108. (JIF) The collective gonadal (testes and ovaries) dore to the general population of about 2 million persons living p i within a 50-mile radius of the Three Mile Island facility is es-timated to be no greater than about 12 person-rems, and the aver-
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age exposure is about 0.005 mrem per person in the exposed popu- I The highest gonadal dose to any maximally exposed lation.
individual is taken here to be no greater than 1.4 mrem. Since the distribution of dose among the population is of no ccnse- 1 quence below 100 mrem, the number of genetic effects may be cal-culated from ',he BEIR III estimates by simple dose proportion- lt ality. Thus, the BEIR III first generation estimate of between 5 and 75 cases becomes 5-75/100,000, or 0.000025 to 0.000375 cases !
I per million live births. 'l It is assumed that the present population of about 2 million will be stable in the future and if the generation time ;
of populations is taken to be 30 years as an approximation, then ,
we would expect about 30,000 births per year, of which about 3,000 (30,000 x 0.107, where 10.7 percent is the current sponta- i neous incidence of genetic disorders of all human live births) ;
would have been affected at some time in life by genetically re-
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i lated ill health irrespective of the AGW. The estimated 0.005 .
! mrem average exposure from the evaporation of the AGW wculd add
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between about 0.000001 (0.000025 cases per million births x :
30,000/1,000,000) and shout 0 00001 induced cases. Expressed an-1
' L other way, the incidence of genetically related ill health in the 50-mile population is estimated to increase as a result of radia- ;
i tion exposure from the accident generated water by no more than ;
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f 0.0000004 percent (0.00001/3,000 x 100) of the spontaneous inci-dence.
In addition to the total population risk, we may also consider the maximum credible risk to the maximally exposed indi-vidual. A:S an extreme "worst case," it might be assumed that a couple who each received an individual gonadal dose of 1.4 mrem subsequently have a child. In the absence of their radiation ex-posure, the risk that child will experience genetically related ill health at some time in its life is 10.7 percent. From the BEIR III genetic effect estimates of 5 to 75 per million per rem, we may calculate the added risk attributable to the evaporation of AGW in 0.0000007 to 0.000012 percent (5-75 x 10 -6 x 0.0014 rem x 100). In other words, the risk is increased in this "worst case" example from the normal 10.7 percent to a maximum of 10.700012 percent.
From the BEIR III equilibrium estimate of between 60 and 1,100 cases per million live births per rem of parental expo-sure, we may t'urtner conclude that the average parental exposure of 0.005 mrr.m to the approximately 2 million population within 50 miles of the Three flile Island facility may result ultimstely in a total of no more than about one-two hundredth of one additivnal case of genetically ralated ill health per million live birtha during all future existance.
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