ML19209C366
| ML19209C366 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 09/11/1979 |
| From: | Eisenhut D Office of Nuclear Reactor Regulation |
| To: | Shurts W AFFILIATION NOT ASSIGNED |
| Shared Package | |
| ML19209C367 | List: |
| References | |
| NUDOCS 7910150166 | |
| Download: ML19209C366 (7) | |
Text
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o UNITED STATES 8")e
',i NUCLEAR REGULATORY COMMISSION E
WASHINGTON, D. C. 20555
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Docket No. 50-10 SEP 111979 Mr. Will Shurts R. R. 1, Box 96 Henry, Illinois 61537
Dear Mr. Shurts:
This is in response to your letter dated July 30, 1979, to Dr. Hendrie which requested that an Environmental Impact Statement (EIS) be prepared prior to the chemical decontamination of Dresden Nuclear Power Station, Unit No.1.
We are currently reviewing the need for such an impact statement for the decontamination as a result of a petition by Mrs. Kay Drey dated March 10, 1979.
A copy of our r.esponse to Mrs. Drey and the related Federal Register notice are enclosed (Enclosure 1) for your infomation. Please be assured that the Dresden decontamination will not go forth until the need for an Environmental Impact Statement is resolved.
We will provide you with copies of our decision on this matter when we have comaleted our review.
With respect to the specific questions posed in your letter, the following answers are provided:
Ql. "What is the substance that is to be used in the decontamination?"
A.
The substance that is to be used in the decontamination is called Dow Nuclear Solvent 1 (DOW NS-1).
Q2.
"What is NS-1?"
A.
NS-1 is a proprietary organic acid developed by Dow Chemical Company. Dow Chemical Company has provided the Nuclear Regulatory Commission with the infomation needed to assess
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the safety and environmental considerations related to the use of Dow NS-1 at Dresden Station. Under the provisions of Section 2.790 of Title 10, Part 2 of the Code of Federal Regulations the Nuclear Regulatory Commission has detemined that the composition and fomulation of Dow Nuclear Solvent NS-1 contains trade secret infomation which should be withheld from public disclosure.
Copies of our June 16, 1978 letter to Dow Chemical Company and an earlier related letter dated April 30, 1975 on this matter, are enclosed (Enclosures 2 and 3) for your i,nformation.
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Mr. Will Shurts Q3.
"How dar.gerous is it [Dow NS-1] to the environment and the people working with it?"
A.
The chemical decontamination of the Dresden 1 primary coolant system will be perfomed entirely within a closed decontamination system. The system has been designed so that no cheMcal or radiological wastes will be released to the environment from the decontamination process. All wastes generated in the process will be either solidifed r.
for offsite burial at a licensed burial ground or reprocessed for reuse onsite. The solid wastes produced are similar in type and quantity to those handled routinely at the site.
The occupational exposure to the workers at Dresden 1 is being minimized by carefully planning the decontamination program and training the workers to carry out their tasks as quickly and efficiently as possible. Commonweal th Edison has estimated the radiation exposure that is expected to be received during each discrete task involved in the cleaning procedure. The high exposure tasks have been evaluated to minimize operator exposure by shielding and preplanning. Emergency procedures have been developed to minimize personnel exposure in the event of a malfunction.
We have reviewed the licensee's submittals regarding occupa-tional exposure and have concluded that Commonwealth Edison has taken appropriate measures to assure that occupational exposures will be maintained as low as reasonably achievable during the decontamination and waste treatment operations at Dresden Unit 1.
Q4.
"Will the pipes be able to stand the tremendous corrosive properties of it?"
A.
The decontamination solution has been specifically developed by Dow Chemical to preferentially dissolve the thin layer of corrosion products that are deposited on the inside surface
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of the primary coolant system without attacking the base metal upon which the corrosion products are deposited.
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Mr. Will Shurts SEP 111979 An extensive materials test program has bean completed by the licensee to provide assurance that the decontamination solution will not cause excessive corrosion to the primary coolant system components. This program evaluated the corrosion resistance of the materials that will be cleaned by the Dow Solvent. Based on the results of these studies we have concluded that the, corrosion of the primary coolant system components will be acceptably low.
The NRC staff will require the licensee to closely monitor the time, temperature, and chemical composition and concentrations to assure that the actual Dresden 1 cleaning process is perfomed within the range of variables of the material test program.
Q5.
"What will be the consequences of it causing a weakened weld to give way?"
A.
The above mentioned materials test program has provided reasonable assurance that the structural integrity of the primary cooling system at Dresden will not be adversely affected by the decontam-ination. However, to assure that the decontamination does not damage the primary coolant system we will require that Commonwealth Edison carry out a comprehensive pre-service inspection to assure the integrity of the primary coolant system and assess the effect of the chemical cleaning on safety-related components that have been in contact with the cleaning solvent.
In addition to these special inspections, all the nomal inspections and tests required by the Dresden Te::hnical Specifications before returning the reactor to service following each refueling outage will be carried out.
Q6.
"Where and how will this [ decontamination] waste be stored until it is removed from the site?"
A.
The waste from the decontamination will be stored in the waste treatment facility located approximately 200 feet east of the Dresden Unit I containment sphere. The waste will be transferred to the waste treatment facility through a double walled shielded pipe with leak detection between the walls to detect leakage before it can reach the environment.
The waste treatment facility contains 4 liquid waste storage tanks with a total capacity of 500,000 gallons. The following quantities of liquid and radioactive materials are expected to be generated during the cleanup:
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Mr. Will Shurts SEP 11 GT3 STEP VOLUME ESTIMATED ACTIVITY (1) Testing 100,000 gal.
O Curies (2) Cleaning 100,000 gal.
2850 Curies (3) ist Rinse 100,000 gal.
142.5 Curieg (4) 2nd Rinse 100,000 gal.
7.125 Curies (5) 3rd Rinse 100,000 gal.
0.36 Curies These tanks are contained within a leak proof building which will retain the entire 500,000 gallon liquid inventory of the 4 waste storage tanks without release to the environment if the tanks were to rupture. The building is designed to maintain its integrity during the maximum intensity earthquake postulated to occur at the Dresden Station.
Q7.
"How will it be transported?"
A.
The radioactive waste that is flushed from the system will be evaporated to reduce its volume in the radioactive waste facility.
After evaporation the concentrated liquid waste will be solidified using Dow Chemical's Solidification Process for Low Level Radio-active Wastes. Afti' solidification the waste will be transported by a commerical radioactive waste disposal carrier in approximately 1200 55 gallon drums. The waste will be packaged and shielded to meet all applicable transportation requirements.
08.
"Does this corrosive substance contain chelating agents?"
A.
The waste solution generated by the decontamination will contain chelating agents.
Q9.
"If so, how will it be disposed of?"
A.
The decontamination solution from Dresden will be solidified to immobilize the radioactive material present in the waste, and buried in a dry solid waste disposal site where interaction with ground water is minimal.
Q10.
"In view of the waste leaks at Hanford, Wa., Maxey, Ky., and Sheffield, Il., can such a solution be disposed of safely?
Can anyone guarantee that it will not work its way into the eco-system?"
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A.
The waste from this decontamination will not be disposed of as a liquid.
It will be solidified into a free standing solid monolith that precludes leakage to the surrounding environment.
In addition, the licensee, Commonwealth Edison, has proposed to have this solid waste buried at either Beatty Nevada or Hanford Washington. The ground water level at these sites'is approximately 300 feet below the surface. The absence of ground water in the burial trenches and the very low rates of precipi-tation (approximately 4 inches per year) provides additional assurance that radioactive materials will not enter the env ironment through leaching from the buried solid waste.
Qll.
"What precautions have been taken to insure the safety of people living in the Morris area?"
A.
The decontamination of the primary system and the processing of the liquid waste into a solid form will take place inside of a confined volume where all potential paths for the release of airb'orne or liquid radioactive material are monitored.
In addition, the air exhausted froit areas of high potential for airborne radioactivity is filtered through high efficiency particulate filters to remove airborne particulate radio-activity. These provisions will assure that no unmonitored, untreated effluents are discharged to the environment.
During the waste solidification phase of the decontamination the liquid waste will be stored within a leak proof, earth-quake resistant waste treatment facility. This building has been designed to contain the entire quantity of liquid waste produced by the decontamination. Therefore, even if the waste storage tanks were to fail no liquid waste would be released to the local environment.
Q12.
"Has there been a plan submitted to evacuate the residents in the event of an accident?"
A.
No plan has been submitted to evacuate residents in the event of an accident related to the decontamination of Dresden Unit 1.
We have reviewed the licensee's plan for the decontamination and have not identified any aspect of the project that will result in any new hazard not previously considered in the licensing of the Dresden Station.
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Mr. Wil1 Shurts SEP 11 1979 Q12.
"Is there any possibility of any contamination getting into the Illinois river? If so, what will happen in cities downstream that draw their drinking water from the river?"
A.
le have reviewed the decontamination program proposed by Lommonwealth Edison. We have concluded that adequate procedures have been prepared and will be followed to provide reasonable assurance that no contamination from the decontamination will be discharged into the Illinois River.
Q13.
" Estimates of the cost of the decontamination have been placed at over $400 million. Who will bear this cost? Will the citizens of Illinois bear the cost? Will Com Ed ratepayers bear the cost? Will Com Ed alone bear the cost?"
A.
The decontamination is estimated to cost between 30 million and 40 million dellars. The United States Department of Energy has provided up to 8.25 million dollars of the cost and Commonwealth Edison will pay the balance of the cost for the decontamination.
Q14.
"How long will this cleaning extend the operable life of the Dresden i plant? How much electricity will be generated in that extended period? Will the net gain in electricity be worth the estimated $400.lillion cost?"
A.
Operating License No. DPR-2 issued to Dresden Unit 1 expires on May 4,19%. The cleaning of the reactor primary cooling system does not extend the operating life of the facility in any way
'aeyond that date. Therefore there is no extension caused cr pennitted by this decontamination.
Q15.
"The most important question to be answered is how will this decontanination affect the health and safety of the citizens and environment of Illinoi:?"
A.
Because the decontamination will be carried out within a closed system, and all waste processing will be accomplished within a specially designed shielded building, and all transportation will be strictly regulated in accordance with all applicable NRC and Department of Transportation regulations, there will be no increased hazard to the health and safety of the citizens of Illinois or any degradation of the envirorrient in Illinois.
e 11'6 145
7-SEP 11579 Mr. Will Shurts Q16.
"Second to that is what will be the consequence of not decontaminating the Dresden 1 plant?"
A.
The most significant consequence of not decontaminating the Dresden 1 plant would be that the employees at the facility would be subject to radiation exposure over the remaining lifetime of the plant that could be avoided. We believe that the reduction of the occupational exposures to plant personnel, is an important benefit of the proposed cl eaning. This reduction in occupational exposure will improve the safety of the plant by allowing more safety inspections, plant modifications, and repairs to be carried out in lower radiation levels than would be present without the decontamination.
- incerely, k
l Dar el Eisenhut, Acting Director Division of Operating Reactors
Enclosures:
1.
Letter to Mrs. Kay Drey/
Federal Register 2.
Letter dated 6/16/78 3.
Letter dated 4/30/75
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