Draft
Comments on: "Draft Phase III Report Devoted to Development of
Conceptual Site Model and Likely Response Actions"
Developed by the LEHR Core Project Team, March - April 1995

Submitted by

G. Fred Lee, PhD, MSPH, DEE
Technical Advisor to
Davis South Campus Superfund Oversight Committee
G. Fred Lee & Associates
El Macero, CA 95618

August 1995

In March and April 1995, meetings were held of the LEHR national Superfund site Core Project Team (University of California, Davis - UCD, Department of Energy - DOE, US Environmental Protection Agency Region IX - US EPA, Cal EPA Department of Toxic Substances Control - DTSC and the Central Valley Regional Water Quality Control Board - CVRWQCB) ("Team") to develop a conceptual model of the pollution of the LEHR site and to discuss possible likely response actions that could be taken to remediate this site based on the current understanding of the sources, transport, fate and significance of waste constituents at the LEHR site. The public potentially impacted by the LEHR site was not involved in these discussions. Presented below are comments on the draft (Phase III) document that evolved from the UCD, DOE, US EPA, DTSC and CVRWQCB staff discussions of LEHR site characteristics and possible remediation approaches.

Presented below is a summary of the key issues that the author (Dr. Lee) feels should be considered in developing a remediation approach for the UCD - DOE LEHR national Superfund site.

Past waste disposal practices by the University of California, Davis at its campus landfills and possibly campus wastewater treatment plant located at what is now called the LEHR site and by UCD and DOE as part of LEHR site research have resulted in pollution of soils and groundwaters by hazardous and deleterious chemicals that impair the use of the area and groundwaters.

At this time, the full extent of pollution of the LEHR site soils and groundwaters and offsite soils and groundwaters is not known.

The potentially impacted public by past LEHR site waste disposal practices will work through DSCSOC toward complete remediation of the LEHR site and any offsite pollution. This remediation shall be in accord with state of California regulatory requirements.

To the extent that any residual waste components are to be left at the LEHR site as part of remediation, the management of these wastes shall be in accord with state of California Title 22 and Title 23 requirements.

Any "hazardous" wastes left at the site shall be managed in such a way as to provide for full containment of the wastes for as long as any waste components represent a threat to public health, the environment and groundwater resources.

Any so-called "non-hazardous" wastes left at the site after remediation shall be managed in accord with Title 23, Chapter 15 requirements that prohibit the impairment of use of groundwaters by waste-derived constituents for as long as the wastes left at the site represent a threat to groundwater quality. This requirement, in accord with Chapter 15 regulations, considers all impairment of uses including aesthetic quality. Further, in accord with Porter-Cologne requirements, any waste-derived constituents left at the site after remediation must not pollute the unsaturated zone under the waste management unit with chemical constituents that represent a "threat" to groundwater pollution.

The draft Phase III document developed by the Team appears to not adequately consider the regulatory requirements of the state of California in managing hazardous and so-called non-hazardous wastes by landfilling. These requirements as set forth in Chapter 15 explicitly require the protection of groundwater quality from impaired use for as long as the wastes in the landfill represent a threat.

The wastes in the existing UCD campus landfills and in the various disposal pits, trenches, drywells, former sludge-drying beds, etc. will be a threat to groundwater resources effectively forever.

The draft Phase III document proposed approaches for on-site waste management as part of LEHR site remediation do not properly consider the ability of the waste containment structures, such as liners, landfill covers, etc., to perform in accord with Chapter 15 requirements of protecting groundwaters from pollution by waste-derived constituents for as long as the wastes represent a threat.

As proposed by the Team in the draft Phase III document, several of the possible on-site remediation approaches, such as capping current waste management units with a RCRA or some undefined "less expensive cap" as well as the development of a RCRA Subtitle C hazardous waste landfill, will only slow down or in some cases postpone for a period of time when additional pollution of the groundwaters hydraulically connected to the waste management units will occur. These proposed approaches for on-site waste management as part of LEHR site remediation do not conform to state of California regulatory requirements and, therefore, cannot be approved for the LEHR site.

The projected costs associated with various on-site waste management approaches as part of site remediation are far lower than the real costs that will have to be borne by UCD and DOE associated with post-closure activities for on-site waste management.

At this time, the draft Phase III Team Report cannot be used as a reliable basis for formulating LEHR site remediation approaches since it does not properly consider state of California regulatory requirements for on-site waste management and the associated costs of providing on-site waste management as part of site remediation.

It is recommended that the draft Phase III Team Report be re-discussed this time involving the public - DSCSOC and others as appropriate where proper consideration of state of California regulatory requirements and associated costs for remediation involving on-site waste management are incorporated into a revised Phase III Report.

Page 3, under "Expected Site Conditions" mentions the potential for groundwater pollution by LEHR site-derived wastes. While mention is made of a lower hydrostatigraphic unit, it is not clear that consideration is being given to the aquifer below HSU-2 which is the aquifer that is used primarily as a domestic water supply in the region. There are at least eight municipal water supply wells within the current projected sphere of influence of waste-derived constituents that could be impacted by past waste management practices at LEHR that take water from the second aquifer underlying LEHR.

In the listing of potential waste sources, no mention is made at the LEHR site of the UCD former wastewater treatment plant and the sludge-drying beds that were associated with this plant. This is an area that needs to be investigated as to the degree that the sludge-drying beds have polluted the unsaturated and saturated aquifer systems under the LEHR site.

Page 3, item 3 discusses spills. Thus far in this report, as well as in other reports, no mention has been made of investigating the radium-226 and strontium-90 that overflowed into the parking lot across Old Davis Road and into Putah Creek. Has the soil in this area been contaminated by radioactive and hazardous chemicals? The basic issue is whether the soil in these areas has been contaminated by radioactive and hazardous chemicals associated with these spills - overflows. A site-specific study of this issue needs to be conducted to determine whether there are residual radioactive and other wastes in the areas where the spills occurred and where the spills - overflows were managed by transport to Putah Creek.

On page 4 mention is made that the "Team" ranked groundwater as the primary overall concern but agreed that the first priority should be given to general response actions for continuous releases from sources to the sub-surface soil. The second bulleted item on this page mentions "Current data indicates that groundwater contamination does not demand immediate attention or an emergency action." At that time, the Team was operating under the premise that the groundwaters were moving only at about an average velocity of 57 feet per year. In light of the fact that as of June 13, 1995 when DOE staff contractors concluded that the 57 feet per year was not based on a valid assessment of the information available and that a more appropriate assessment indicates that the groundwaters may be moving at a rate of about 1,000 feet per year, it is appropriate to examine again the relative priorities assigned by the Team for investigating offsite groundwater pollution versus controlling ongoing sources of pollution.

The change in estimated groundwater velocity significantly changes the perception of the significance of the pollution of groundwaters by LEHR site-derived waste with respect to being an offsite threat. As discussed in the Lee (1995) draft "Bottled Water Issues" report that is under review at this time, the offsite groundwater quality monitoring program that has been conducted by UCD at nearby neighbors' production wells is highly deficient compared to the program that is needed to properly define whether LEHR site-derived wastes have polluted offsite groundwaters adversely impacting water quality and most importantly, whether at some time in the near future highly significant offsite groundwater pollution will occur that affects a nearby neighbor's production well.

The author feels that there is need to examine the appropriateness of assigning second priority for considering the current contaminated groundwater remediation in light of the new information available on the potential sphere of influence of the polluted groundwaters at the LEHR site. Assigning a lower priority to a potentially significant real public health issue is not, in the author's opinion, appropriate in light of the current degree of understanding of the extent, degree and significance of groundwater pollution that has occurred at the LEHR site. That priority can only reliably be assigned after the leading edge of the several and possibly numerous plumes that exist at the LEHR site from the various waste management units has been defined.

Figure 1 on page 5 presents a Conceptual Model of the LEHR site. Added to this figure should be the UCD sewage treatment plant.

This Model omitted a potentially significant pathway as a release mechanism for radioactive and hazardous waste. This pathway is the translocation of hazardous substances from the disposal areas through the roots and release either to the atmosphere or more importantly through the vegetative structures to the surface of the soil. As far as the author, Dr. Lee, can ascertain, this mechanism of transport of waste-derived constituents has thus far apparently not been adequately considered and apparently has not been investigated. It is well known that plants can take up certain chemicals and elements from the soil. Since there are a large number of shallow disposal pits which have various types of vegetation associated with them, such translocation could be a source of hazardous chemicals to wildlife and through stormwater runoff from the LEHR site to Putah Creek. A detailed sampling program of this vegetation for a wide variety of constituents that are of potential concern to public health and wildlife should be conducted in the near future to ascertain what, if any, translocation of hazardous chemicals has occurred. Periodically, these studies should be repeated.

Another deficiency in Figure 1, "Conceptual Model Found in the RI/FS Work Plan" is that only the upper and lower hydrostatigraphic units are considered to be susceptible to pollution from wastes at the LEHR site. It appears that no consideration was given to the second aquifer which underlies HSU-2. It is the author's understanding based on discussions with D. Parfitt that the city of Davis wells, many of which have depths to approximately 500 feet, are screened in both HSU-2 and in the underlying aquifer to HSU-2. This screening and gravel pack around the wells could be a significant transport mechanism for transferring LEHR site derived pollutants to the domestic water supply wells within the sphere of influence of the LEHR site. This area needs to be investigated and included in the site Conceptual Model.

Page 6 under Source Numbers 1 & 2 mentions "Combined radium-226 and strontium-90 leach fields as one source area." While it is not clear what change in the investigation would occur because of combining the leach fields for radium-226 and strontium-90, if these leach fields are the same field, then it is appropriate to combine them. If they are not the same field, i.e. two different systems, then it may be appropriate to keep them separate based on the potential difference in the transport of these two radionuclides in the geological strata associated with the leach fields. Similar issues may exist with respect to Source Number 11, the septic tank systems and Source Number 9, the Imhoff underground tanks. Each of these could have been a discrete source. If they are all located close together and adequately investigated, they could possibly be combined into a single source. Further information is needed before a definitive conclusion can be reached by the author on this matter.

Page 10, Figure 2 presents the "Revised Conceptual Model." Many of the same problems that were discussed in the original conceptual model such as failure to consider translocation, failure to consider pollution of the second aquifer occur in this Revised Model as well.

On page 11 under "Radium and Strontium leach fields" the statement is made that, "Public concern exists because of clogging of the system may have resulted in spills." That is an inappropriate description of the situation. There were spills of radioactive waste on the soil surface which are well documented in previous site reports. This is not a situation of "may." The word, "may," is inappropriate and misleading.

Beginning on page 11 through page 14 is a listing of various waste disposal units and "Likely General Response Actions." The likely response actions in general range from no action through complete removal of the wastes. For some waste management units, it could include capping, selective removal or in situ treatment. As discussed below, it appears that the Team gave inadequate consideration to state of California requirements for managing residual wastes that would be left at the LEHR site as part of site remediation.

Further, throughout this discussion, there seems to be little consideration given to addressing the pollution of the groundwaters by what are sometimes classified as non-hazardous wastes such as total dissolved solids, hardness, taste and odor-producing materials, etc. While these so-called non-hazardous wastes may not be required to be addressed under CERCLA, they are of great concern to the public and are required to be controlled and remediated under state of California Chapter 15 requirements and under the Central Valley Regional Water Quality Control Board's Basin Plan.

Page 15, Figure 3 does not include the former UCD wastewater treatment plant. It should be added to this figure.

Page 16, Section V, "Development of Data Needs," presents a discussion of the results of an April 4 and 5, 1995 meeting of the project Team devoted to the data needs to address the "...probable general response actions identified for sources of contamination at the site." On page 16, it is stated that the Team was unable to come to a resolution of what specific data needs exist for the UCD campus landfills at the LEHR site in connection with developing a remediation approach. Part of this problem could arise from the fact that it appears that the Team did not fully understand the difference between state of California requirements and US EPA requirements. State of California requirements take precedent over US EPA requirements since they are stricter - more protective of public health and the environment.

It is important to understand that with respect to the discussion of capping of the landfill that this capping must be done with a cap that will, in fact, conform to Title 22 requirements and Chapter 15 requirements with respect to the overall performance standards set forth in these regulations of public health and groundwater resource protection.

There is need for the Team, and especially the regulatory agencies' representatives, to clearly define the performance standard, proposed design and maintenance, as well as the associated funding for maintenance for any landfill caps that might be placed on UCD campus landfill units 1, 2 and 3 and on any waste management trenches, pits, etc. that are located at the LEHR site. With this specific information, the public (the author) can then comment on the adequacy of the proposed approach relative to regulatory requirements and the expected behavior of the materials that are proposed for capping the landfills and other waste management units.

The author has many years of experience including conducting research devoted to assessing the ability of compacted clay and flexible membrane plastic sheeting of the type used in landfill liners and caps to protect groundwater resources from pollution by landfill leachate for as long as the wastes in the landfill represent a threat. He is also familiar with the regulatory requirements of Chapter 15 where, while a professor in the University of Texas system, he served as an advisor to the state of California Water Resources Control Board staff in the early 1980s as part of developing the current Chapter 15. Since returning to California in 1989, he has been highly involved work in revising Chapter 15.

The author has spent considerable time in the past several years devoted to evaluating the reliability of various types of landfill capping approaches, and is presenting an invited paper at the American Society of Civil Engineers national landfill closure symposium that will be held in San Diego in October 1995 devoted to these issues. Further, this past weekend, he presented an invited discussion in San Luis Pontosi, Mexico on the design of hazardous waste landfills to provide for true public health, environmental and groundwater quality protection from hazardous wastes in RCRA landfills. He is, therefore, highly familiar with the issues pertinent to capping and the construction of on-site landfills at the LEHR site.

There is concern that the Team in developing the draft Phase III report did not adequately consider the state of California regulatory requirements setting forth the overall performance standard for any landfill cap that could be used at the LEHR site as part of site remediation. The Team and the public must develop an agreement on the overall performance standard with respect to protecting groundwater from further pollution that will govern any on-site remediation approach such as capping landfills and/or constructing a new RCRA landfill at the LEHR site.

The overall groundwater protection performance standards are explicitly set forth in California regulations. It is important not to make the mistake that is sometimes made of assuming that the minimum design standards for a landfill containment system component will necessarily achieve the overall performance standard governing groundwater quality protection. It appears that this may have been done by the Team in selecting possible remediation alternatives for the LEHR site.

Next, the Team and the public need to agree on the expected performance of any proposed design of a landfill cap and the adequacy of the proposed maintenance approach and the associated funding for this maintenance to achieve the overall groundwater protection performance standard. It is the author's experience that while it is possible to develop landfills and landfill caps that will achieve the state of California groundwater protection performance standards set forth in the regulations, this cannot be done at the LEHR site with the approaches proposed in the draft Phase III report. This is an issue which will require detailed discussion by the RPMs and the public.

On pages 18 through 24 are some general discussions about regulatory requirements, data needs, etc. Before the public can effectively review this material, more detailed information is needed on what is envisioned with respect to site-specific application of various technologies to the LEHR site.

Beginning on page 29, there is a discussion of "Relative Cost Comparisons." A review of the costs and approaches established shows that the costs of some of the recommended proposed approaches are likely significantly less than the real costs that will be incurred. For example on page 30, there is a discussion of capping of landfills with a RCRA cap where the estimated cost is $250,000 per acre.

The $250,000 per acre landfill cover is described as a cover consisting of a flexible membrane liner, compacted clay layer, a sand drainage layer and topsoil layer. This design represents the typical minimum cover requirements for a RCRA landfill; however, such a design will not achieve the overall performance standard required in the state of California regulations Title 22 or 23. It appears that the Team in developing these landfill capping costs did not review the state of California regulations presenting the overall groundwater protection performance standard that has to be achieved by a landfill cover.

The draft Phase III report also mentions in this section,

"Less expensive capping alternatives, that meet minimum California regulatory requirements for closing old landfills, might reduce the unit cost for capping by as much as 40%."

With regard to this statement that less expensive capping alternatives that meet California regulation requirements for closing landfills could save about 40%, the particular cover envisioned for 40% less cost is not described. There is no doubt that since the cover described herein which costs $250,000 per acre will not be effective in achieving the groundwater protection performance standard of preventing groundwater pollution by waste-derived constituents for as long as the wastes represent a threat, certainly the 40% less expensive cover will also not achieve the performance standard necessary to protect public health, groundwater resources and the environment as required under California regulations.

Another significant deficiency with the $250,000 per acre amount for a landfill cover is that it considers only the initial cost of the cover. It does not address the replacement costs that will have to be borne by UCD - DOE in perpetuity for as long as the landfill exists. Periodically, the flexible membrane sheeting will have to be replaced, and the clay liner system will have to be rebuilt if the landfill cover is to function as required by state of California regulations of preventing sufficient moisture from entering the landfill for as long as the wastes represent a threat to generate leachate which can then lead to the pollution of groundwaters hydraulically connected to the landfill.

It is important to note that the pollution of the unsaturated media under the landfill by landfill leachate would be in violation of state of California regulations as set forth in the Porter-Cologne Act of causing a "threat" to groundwater quality at the LEHR site. Therefore, while the state of California does allow the construction of less expensive landfill covers, state regulations are explicit in requiring that whatever is done with respect to covering landfills, they must prevent the contamination of the unsaturated zone under the landfill as well as the groundwaters hydraulically connected to the landfill by landfill-derived constituents that can impair the use of these waters for as long as the wastes represent a threat. With few exceptions, most of the constituents in the landfills that exist or could be developed at the LEHR site will be a threat effectively forever.

Bottom of page 30 and top of page 31 discusses the potential remediation associated with the vadose - unsaturated zone soils under the waste management units. The statement is made,

"Whether there are any areas of concentrated contamination that can or should be excavated or remediated in place has not been determined."

Again, it appears that the Team is not familiar with California's regulations. Porter-Cologne is explicit in requiring that any wastes present in the unsaturated zone that represent a threat to groundwater have to be remediated. Even if the waste management unit wastes are removed, there still will be a significant threat to groundwater from contaminants present in the unsaturated zone that will need to be remediated. While it is possible to construct an impermeable cover over the area to cut off moisture transport through the unsaturated zone and thereby prevent groundwater contamination by non-volatile vadose zone-associated constituents, for volatile constituents such as the chlorinated solvents, radon, etc., there is a potential for gas phase transport to groundwaters that can lead to groundwater pollution. California's regulations require remediation of such situations.

The remediation of gas phase transport may require horizontal drilling of extraction wells in the vadose zone to remove volatile waste constituents from this area. It is not possible at this time to estimate the costs of management of the waste-derived constituents in the vadose zone associated with each waste management unit since insufficient information is available at this time on the type, degree and extent of vadose zone contamination. There is no question, however, that contamination is sufficient to be a threat to groundwater quality and therefore, the remediation of the vadose zone will have to be addressed for each waste management unit. There is no doubt that substantial funds will have to be spent by UCD and DOE in remediating - effectively controlling waste-derived constituents in the vadose zone associated with each waste management unit at the LEHR site.

Page 31, the first full bulleted item discusses groundwater contamination where it states that the costs of groundwater remediation may be altered by source control efforts envisioned. While insufficient information is provided on what is meant by this statement, it is important that UCD - DOE understand California regulations with regard to groundwater quality remediation. Fundamentally, under current regulations, groundwater remediation has to take place to the maximum extent practicable for all constituents that impair the use of the groundwaters for any beneficial use. These requirements are not limited to a few hazardous chemicals on US EPA or state of California lists but apply to all constituents, including constituents that can cause taste and odors in groundwater in accord with the Central Valley Regional Water Quality Control Board's Basin Plan.

Remediation will have to be completed for TDS if the concentrations of TDS in the waste-contaminated areas derived from the wastes exceed background. It appears that the Team in developing this Phase III document focused on federal requirements and ignored state of California requirements for groundwater quality protection. The state of California requirements are far more protective of groundwater quality than the federal requirements. Therefore, the state of California requirements take precedence in establishing remediation objectives for contaminated groundwaters. Basically, the public is entitled to the remediation of groundwaters to the maximum extent practicable so that there is no further impairment of use from all contstituents whether labeled hazardous or not by the arbitrary definitions that are used today.

Adjacent property owners should be entitled to use the groundwaters associated with their property in perpetuity without any impairment of use by waste-derived constituents from past waste management practices at LEHR. UCD and DOE will be required, in accord with current California regulations, to clean-up the contaminated groundwaters that were caused by their waste management activities at the LEHR site. From what is known now about remediation of groundwaters, this will be a process that will likely take many tens to hundreds of years of pump-and-treat provided that there is, in fact, effective control of the sources. If only a superficial control of the sources of waste constituents is practiced, such as installing low-permeability covers that will only reduce the rate of moisture entering the waste management unit that generates leachate, then UCD and DOE will be involved in groundwater remediation effectively forever.

Page 31, in the second full bulleted item regarding costs associated with a DOE site, does not provide sufficient information to understand the issue, i.e. why is there a difference between cleaning up a DOE site versus any site? It is doubtful that DOE has more stringent requirements for remediation than the state of California. The fact that it is a DOE site would not likely be a significant factor in establishing the basic costs for site remediation.

Page 32, "Alternative 1" summarizes information on a proposed on-site RCRA landfill which would take the wastes and contaminated soils associated with various waste management units at the LEHR site. As discussed above, a conventional RCRA landfill of the type described at best only postpones when further groundwater pollution occurs at the landfill. Such a landfill will not, therefore, meet state of California regulations governing the management of hazardous wastes. While, in the opinion of the author (Dr. Lee), it would be possible to construct an on-site landfill for managing wastes and contaminated soils that would be protective, the costs of construction and, most importantly, the in perpetuity maintenance and monitoring will certainly be far more than anything envisioned by the Team in their development of the Draft Phase III document.

The issue of what will be an acceptable on-site landfill is of such fundamental importance to the public that it is suggested that this issue needs to be resolved in the near future. Without appropriate resolution, it will be impossible to plan remediation of the LEHR site in a meaningful way.

On page 32, the next-to-last bulleted item discusses the western dog pen soils, where it mentions that, "The Western Dog Pen Soils would be excavated to six inches below the existing, clean gravel, a total of 2,100 cubic yards." There can be little doubt that appreciable radioactive and other wastes have been transported into the vadose zone and likely to the groundwaters under the dog pens via rainfall and the sprinkling of the dog pens whenever the temperatures reached a certain value. The sampling program that has been conducted thus far under the dog pens has not been adequately done to define the pollution that has occurred. There could be appreciable pollution of the vadose zone under the dog pens which would be a Porter-Cologne threat to groundwater pollution and which would require that rather expensive remediation of the dog pen areas beyond that described in the Phase III document be undertaken.

On page 33 under "Sensitivities," it is stated,

"Other than the major cost determinants noted in the Introduction, no additional factors have the potential to significantly affect the total cost of the alternative as estimated here."

That statement is not reliable. It does not properly consider the state of California regulations governing landfilling of wastes that will have to be complied with by any on-site landfill.

Page 34 presents "Alternative 2," which is basically to construct a RCRA landfill for all wastes except landfills 1, 2 and 3. Landfills 1 and 2 and many of the waste hole - disposal trenches would be capped with a RCRA cap. This approach has the same difficulties noted for Alternative 1 in that a RCRA landfill of the type described cannot be constructed in California and comply with California regulations.

Further, as discussed elsewhere, the types of caps that are envisioned for landfills 1, 2 and 3 in the adjacent waste disposal areas will not comply with state of California regulations. The statement under "Sensitivities" on the bottom of page 35 about a "RCRA cap" is assumed. A simpler cap and perhaps an equally effective cap could be constructed at a reduction in cost as high as 40%. While the characteristics of a simpler cap are not described, it is important to understand that simply developing a RCRA cap will not comply with state of California regulations in terms of prevention of future pollution by the landfill and waste units that are capped.

Page 36 presents "Alternative 3," which involves removal of wastes from sources not adjacent to landfills 1, 2 and 3 and disposal off-site with the capping of 1, 2, 3 and adjacent sources. This is basically Alternative 2 with off-site removal of some wastes. It has the significant problems as Alternative 2. In addition, UCD needs to consider the potential liabilities of off-site waste management. Most off-site waste management is done under RCRA requirements which is not necessarily protective, although in the end the deficiencies in RCRA that exist now, with only 30 years of mandated post-closure care, inadequate groundwater monitoring, etc., will likely be corrected. The long-term liability associated with improper management of wastes off-site will certainly be less than those for on-site because of the economies of size where the wastes are managed off-site.

Page 38 presents "Alternative 4" which involves removal of all wastes to transport off-site. This has some of the same problems as the others coupled with the long-term liability associated with how the wastes are handled off-site.

Page 1, in the "LEHR Cost Estimates," presents a breakdown of costs for various alternatives. As discussed herein, many of these costs are significantly lower than the real cost for that alternative especially for on-site management.

On page 2 of the "LEHR Cost Estimates, Alternative 1," mentions a 30-year O&M present worth at $1,040,000. That figure is significantly low for the 30-year period. That level of funding will not provide for the state of California regulations required protection of public health, groundwater resources and the environment during a 30-year period, much less the infinite period that the wastes in the landfill will be a threat. While this approach is conventionally followed on behalf of PRPs, it is highly inappropriate to estimate the costs for remediation based on only 30 years of post-closure care. There are no processes for the majority of the wastes other than natural radioactive decay which would cause these wastes to stop being a threat within 30 years. If a true "dry tomb" landfill is created to store wastes, the wastes at the end of 30 years will be the same as was put in the landfill at the beginning of the 30 years.

One of the factors that will have to be considered as part of the pump-and-treat operations that will inevitably almost certainly have to be installed at the LEHR site will be the treatment and disposal of the contaminated groundwaters. Because of the characteristics of Putah Creek, it is likely that the treatment of the type that UCD is trying to implement for the West Landfill will be found to be inadequate.

Overall, the draft Phase III document is useful to bring issues to the forefront for discussion. The materials presented, however, are significantly deficient in properly addressing the site remediation relative to the state of California regulations especially for on-site management of wastes. The cost estimates for a number of on-site approaches are highly unreliable and significantly underestimate the true costs for management of UCD - DOE wastes at the LEHR site. It is very important that reliable cost estimates be developed for remediation of the LEHR site so that UCD and DOE administrations fully understand the magnitude of the funds that will ultimately have to be spent remediating this site.

It is the author's understanding that one of the reasons for going through the Phase III approach of accelerated remediation of to reduce the costs of remedial investigation of the LEHR site. It is not clear, however, that the so-called Phase III accelerated approach will in any way change what was set forth as needed data in the RI/FS developed in September 1994. It is the author's experience that the basic data needs set forth in the September 1994 remedial investigation will not be any less because of this so-called accelerated approach.