ML20236T499
| ML20236T499 | |
| Person / Time | |
|---|---|
| Issue date: | 10/07/1987 |
| From: | NRC |
| To: | NRC |
| Shared Package | |
| ML20236T493 | List: |
| References | |
| REF-WM-39 NUDOCS 8712010312 | |
| Download: ML20236T499 (3) | |
Text
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OCT 0 71987
SUMMARY
MEETING NOTES NRC/ DOE MEETING TO DISCUSS AQUIFER RESTORATION COSTS AT SELECTED URANIUM MILLS Date:
October 7, 1987 Time:
2:00 - 3:40 Place:
Fifth floor conference room Willste Building, Silver Spring, MD Agenda:
See Enclosed Agenda
Participants:
See Enclosed List 1
Summary:
NRC opened by stating that the purpose of the meeting was to discuss and compare cost estimates for aquifer restoration at the designated uranium mill tailings processing site at Riverton, Wyoming.
After'a brief discussion of the purpose of the meeting, DOE's contractor (Jim Brinkman) summarized the approach used to estimate. preliminary costs for aquifer restoration at the Riverton site. The $36 million cost estimate for restoration is for extraction and treatment of contaminated groundwater from the shallow aquifer' system for approximately 40 years.
Contaminated groundwater would be pumped at a rate of 27,000 gallons per day (GPD) from a trench excavated downgradient from the tailings pile. Groundwater would be restored to comply with the 30 pC1/1 and 0.1 mg/l limits for uranium and molybdenum, respectively. After treatment by sulfide precipitation, the effluent would be discharged to the Little Wind River in compliance with State requirements. The cost estimate includes approximately $19M for daily monitoring of treatment plant influent and effluent ($17.5M) and quarterly monitoring of j
groundwater quality at 12 wells for 24 yea rs ($1.5M).
DOE's l
contractor stated that the cost estimates may be useful to (1) develop more accurate estimates of the costs impacts associated with EPA's proposed groundwater protection standards i
at UMTRAP sites and (2) identify data gaps where additional i
site-specific information (e.g., extent of contamination, aquifer geochemistry) may be necessary to design and optimize aquifer restoration programs.
In addition to Riverton, DOE has also estimated detailed i
restoration costs for UMTRAP sites at Tuba City, Gunnison, Falls City, and Lakeview.
DOE has extrapolated these estimates to estimate a total cost of $800M to $1100M for aquifer restornion at all VMTRAP sites.
The $800M estima.te includes a 25% markup to cover design, engineering, characterization, 8712010312 871014-
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OCT 0 7 MF 002/MFW/87/ TRAVEL a'nd DOE overhead costs.
The $1100M estimate includes an additional 25% markup for contingencies.
NRC started its discussion by comparing the cost estimates developed by EPA, DOE, and NRC for the. Riverton ' site.
The EPA cost estimates are provided in the Background Information Document.- NRC stated that its cost estimation approach was more simple than DOE's approach because NRC did'not model contaminant transport in the shallow aquifer.
Instead, NRC estimated the volume of contaminated groundwater by multiplying the. areal extent of the contaminant-plume above a uranium concentration of 30 pCi/l by the (1) mean thickness of the contaminated aquifer, (2) mean aquifer porosity, and (3) uranium desorption factor of 7 This latter factor is intended to estimate the increase in volume of contaminated groundwater due to uranium desorption from contaminated sands,
. clays, and silts in the aquifer. NRC's $12.2M cost estimate for aquifer restoration at.Riverton includes the costs'for construction and operation of a.1 MGD electrodialysis water treatment plant, construction and operation of wells to extract contaminated groundwater, pumping of groundwater to the treatment plant, and engineering and supervision. NRC's cost estimates do not include monitoring, waste disposal, legal an9 regulatory, and contingency costs.
DOE and NRC agreed that the DOE, NRC, and EPA cost estimates.
are comparable, although the DOE estimates included costs for necessary items (e.g., monitoring and. waste disposal) that were not included in the NRC and EPA estimates.
DOE and NRC,also agreed that the cost estimates are rather crude and, therefore, could not be used as bidding packages for contracting the aquifer restoration.
Further, NRC and DOE recognized that the estimates are particularly sensitive to design assumptions i
(e.g., pumping rate) that require more site characterization and assessment to confirm.
At the end of the meeting, NRC and DOE discussed the significance of the cost estimates with respect to EPA's proposed groundwater protection standards for UMTRAP sites in 40 CFR Part 192. DOE requested that the two agencies meet to discuss coments on the proposed EPA standards prior to the close of the public comment period (October 26,1987).
NRC stated that it would discuss the request internally prior to deciding whether to meet again with DOE prior to the close of the public comment period.
Action Item:
NRC (Fliegel) will respond to DOE (Matthews) about whether NRC will meet with DOE to discuss agency comments on the proposed revisions to 40 CFR Part 192 prior to October 20, 1987.
Enclosures:
As Stated
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UNITED STATES 8
NUCLEAR REGULATORY COMMISSION o
E WASHINGTON, D. C. 20555
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NRC/D0E MEETING TO DISCUSS AQUIFER RESTORATION COSTS AT SELECTED URANIUM MILLS October 7, 1987 2:00 - 4:30 Silver Spring, Maryland AGENDA Introduction DOE /NRC Cost Estimation Approach and Results D0i:
Cost Estimation Approach and Results NRC Discussion DOE /NRC Concluding Remarks DOE /NRC
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