February 5, 1998
State of Nebraska
P.O. Box 98922
Lincoln, Nebraska 68509-9022
Subject: State of Nebraska LLRW Program DSER and DEIA
When the state issued their draft evaluation of US Ecology's license application we were pleased to note that the DSER findings in the most critical areas of site suitability, design, construction and performance were deemed acceptable. The DEIA confirmed the Butte site selection as having minimal environmental impact.
Each section of the document summarized the steps taken by the State and US Ecology through the comment and response phase of the review to arrive at the findings. This was an extremely rigorous process which required a great deal of time and effort for both parties. It was, however, an effort which demonstrated the degree of assurance the State required that this facility would be safe for not only the workers but the surrounding population and environment.
I am not going to address or respond to comments made during this hearing except to note that the comments made on technical issues have been fully addressed in our submittal to the State today.
The last major revision of our Safety Analysis Report was submitted in 1995 after a series of meetings with the state's technical reviewers. US Ecology left these meetings with an understanding that all issues remaining open at that time were satisfactorily addressed. Since that time, additional guidance regarding a number of technical issues has been released by the US Nuclear Regulatory Commission. These were used by the State in their evaluations and by US Ecology in our comments. These are specifically identified in the following summary of our comments to the DSER.
Finding 2.4.2-1 notes that we have adequately characterized the hydrogeology of the site, but questioned our infiltration rate of 0.04 in/yr. In May, 1997,the NRC issued a revised Branch Technical Position Paper for determining facility performance and infiltration rates. Using this new guidance we derived a mean annual recharge of 0.064 in/yr. for the closed facility. We had previously revised our 0.04 in/yr. value to a range of 0.053 to 0.18 in/yr. for the base and bounding cases. The 0.064 in/yr. newly derived value is a bounding case. Since this rate is nearly three times lower than the 0.18 in/yr. case, the work reconfirms the validity and conservatism of our SAR values.
Finding 4.1 addresses the means of ensuring waste disposed at the facility has been properly characterized, classified and manifested by the waste generator. It also requires US Ecology to describe the means by which we will ensure these activities have been properly performed. We have responded to these concerns by following the guidance in NUREG 1200 by describing a graded program of inspections at the disposal facility and the point of generation.
It is in US Ecology's best interest that the waste we receive is entirely as stated by the generator and in compliance with all requirements. Many problems with waste are usually unique. As is our practice at other sites, we will propose to the State a means of remedying each unique problem while satisfying the dual requirements of disposing only waste meeting all requirements and maintaining an effective ALARA program.
Findings in Section 4.3 discuss the need to fill certain void spaces in the Class B/C cell and questioned the number of proposed new on-site wells. We have agreed to fill all void spaces and install additional wells in the buffer zone as requested by the State.
Sections 4.4, 5.2, and 5.3 deal with calculating monitoring, and measuring radiation levels at the facility. In response to these points we will clarify and update our programs to satisfy all concerns. In those areas where we estimated radiation exposures to workers during, for example, site closure, we have pointed out that before any such work is performed we will prepare a complete study and analysis of conditions existing at that time. This information will then be used to prepare specific work plans and procedures to be followed to ensure the work is performed satisfactorily with radiation exposures maintained as low as reasonably achievable.
Section 6.1 contains various findings dealing with our work in describing the radionuclides we project to be received and their modelled performance at the facility. Virtually all of the differences between our work and the States stem from the different time periods we have used for our data base. This is due to the State's comparative analysis being performed approximately two years after ours. The work for our 1995 SAR Rev. 8 was performed in 1994 when complete data only through 1992 was available. We have now revised our source term to coincide with the same period as used by the State. We had also previously excluded nuclides with half-lives of less than ten years. These have been put back into the inventory as well as all daughter products. This updated source term is now as comprehensive as can possibly be made and includes eight full years of data. From this inventory, in response to the State's apparent intent to list all nuclides and activity limits in any license, we have compiled a table of approximately 150 nuclides showing the quantity expected to be received and also a factored quantity the facility can receive and stay within performance limits.
This new data base was put into various models addressing accident scenarios, groundwater transport and releases in air. In all cases the expanded inventory of nuclides did not result in any significant change to the previous results. This work did lead to one positive addition to the facility. While it is extremely unlikely that a high integrity container would ever be dropped from the B/C crane, to further assure that any release from such an accident is contained we decided to enclose the crane. This reduces the off-site accident analysis dose to well below the 10 mrem point at which additional response planning is required. Our detailed response to this finding describes the crane enclosure.
The findings in DSER Section 7 deal with occupational exposure, design features, and organization. Some of these findings stem from different interpretations and understanding of regulatory requirements. While US Ecology felt that methods and procedures used at our sites in other locations would be acceptable, the State's position was that we had not sufficiently satisfied their requirements. In response we have further refined and more fully identified equipment and shielding to be used for certain operations, our identifications of radiation areas and the US Ecology organization to eliminate possible conflicting authorities.
Section 8 of the DSER discusses accidents, emergencies, and procedures. Generally in this area we have clarified the possible locations of potential emergencies and better defined administrative and operating procedures as well as the mechanism for revising these procedures.
Section 10 of the DSER deals with Financial Assurances. While the findings were acceptable, we noted the State's comments regarding disposal rates. In particular, Table 10-2 presents disposal costs based on various waste volumes but without considering operating cost differences for varying volumes.. Recognizing that facility revenue requirements are sensitive to waste volumes, we have prepared new pro-forma balance sheets showing annual costs and rates for a range of waste volumes. The volumes used were supplied by the major generators and are their projections for different processing and disposal options available to them. It is important to note that while some operating costs are reduced, the Closure, Remediation, Institutional Control, and Community Improvement Funds remain fully funded.
We are including in our comment the fact that, under the lowest volume scneario, fewer disposal cells are required. It is likely that our initial construction will require only two Class A cells and a shorter Class B/C unit. We would not build additional cells without reasonable assurance that they would be needed The volumes, revenue requirements and disposal rates are included in our detailed comment.
We are also submitting as part of our exhibit some general comments on the State's documents. These do not relate to a specific DSER or DEIA section, but are relevant to the documents as a whole.
I would like to reiterate US Ecology's philosophy in this process; we are totally committed to building, operating and closing a facility which will not only be safe but in full compliance with all applicable statutes and regulations.
We have made every effort to satisfy the State's remaining concerns.
In the event there are any remaining concerns after the review of these
comments we request the State articulate their requirements more fully
in the form of license conditions.
US Ecology
John H. DeOld
Project Manager