DSCSOC

Comments on "Draft Risk Assessment Protocol"
for the UCD - DOE LEHR Superfund Site
Prepared by Weiss Associates
Dated March 15, 1997

April 20, 1997

Davis South Campus Superfund Oversight Committee
Rt.2 Box 2879
Davis, CA 95616

Remedial Project Managers
LEHR Superfund Site
University of California, Davis
Davis, CA 95616

via e-mail

Dear RPMs,

I have attached a report prepared by Dr. G. Fred Lee, DSCSOC's technical advisor, titled "Comments on 'Draft Risk Assessment Protocol' for the UCD-DOE LEHR Superfund Site Prepared by Weiss Associates, dated March 15, 1997." Dr. Lee's review discusses the problems he finds with the risk assessment approach that is planned. Dr. Lee discusses the significant deficiencies in the information base that is needed to develop a valid risk assessment. Many of these issues raised in Dr. Lee's comments have been previously discussed by Dr. Lee.

Dr. Lee has recommended that this risk assessment document be redone and expanded to address the issues that have been raised in his comments as well as those raised by the other reviewers. DSCSOC is requesting the RPMs make the necessary requests to UCD and DOE to assure that this will be done as the public will not accept anything less than a technically valid and adequate risk assessment of the LEHR site as part of establishing public health and environmentally protective remediation of this site.

If you have questions regarding Dr. Lee's comments, please contact him. If you have questions regarding DSCSOC and this letter, please contact me.

Sincerely,

Julie Roth, Ex. Dir.

cc: DSCSOC's Ex. Board
Dr. G. Fred Lee
William H. Taylor
Jane Riggan
Brian Shaffer

Comments on "Draft Risk Assessment Protocol"
for the UCD - DOE LEHR Superfund Site
Prepared by Weiss Associates
Dated March 15, 1997

April 20, 1997

Julie Roth, Exec. Director
DSCSOC
Route 2, Box 2879
Davis, CA 95616

Dear Julie:

I have reviewed the DOE-Weiss Associates "Draft Risk Assessment Protocol" for the UCD-DOE LEHR Superfund Site and find it significantly deficient compared to the approach that should be used to assess the risk that the existing chemicals present in LEHR site waste management units and contaminated soils as well as ground and surface waters and surface water sediments represent to public health, water resources and the environment. This draft risk assessment is especially important to DSCSOC since it establishes the approach for determining wastes that can be left at the LEHR site after remediation.

Basically, DOE is now attempting to use a limited scope study devoted to site characterization to define the public health and environmental risk that exists at the LEHR site. Prior to initiating the limited scope studies devoted to waste site characterization, DOE and UCD were informed by the RPMs and DSCSOC that they should understand that the limited scope investigation of the existing waste management units could not be used to define whether a chemical constituent could be left at its current location without remediation that included removal based on a risk assessment study. The limited scope studies that have been conducted thus far can only define the need for removal of the waste management unit and all contaminated soils associated with the waste management unit. They cannot be used to define that a constituent in a waste management unit represents insignificant risk. Far more comprehensive waste site characterization studies would be needed for this purpose.

I also find that the approach used in the draft risk assessment approach toward addressing background concentrations of constituents is inappropriate. Further, DOE's approach toward defining constituents of concern is inadequate. In addition, the issue of the risk associated with past and current stormwater runoff from the LEHR site still has not been adequately and reliably addressed. There is first need to develop an adequate, reliable stormwater runoff monitoring program. UCD is highly derelict in complying with DSCSOC and the RPMs request of last summer for such a program. This program should have been in place before the first storm last fall. UCD still has not prepared such a program with the result that another storm season has passed where inadequate characterization of the impact of the stormwater runoff associated constituents on Putah Creek water quality has occurred. As discussed in my comments, it will likely take about two years of properly conducted stormwater runoff impact evaluation before it will be possible to reliably define the risk that constituents in the stormwater represent to public health and the environment. By being highly dilatory in the development and implementation of an adequate stormwater runoff monitoring/impact evaluation program, UCD and DOE have delayed by several years when a proper risk assessment of stormwater runoff impacts can be formulated.

This draft risk assessment is useful from the perspective of beginning to force UCD and DOE to properly characterize the risk that past inadequate waste disposal practiced by UCD represents to public health, ground and surface water resources and the environment. UCD and DOE must consider the issue that has been raised several times in the past of whether they plan to proceed to remove, for off-site disposal, all waste and contaminated soils where only a limited characterization of the existing risks are done as has been achieved thus far, or a comprehensive, in-depth, detailed characterization must be done in order to reliably define the real risk to public health, water resources, the environment and the interest of those within the sphere of influence of the LEHR site associated with the existing wastes as well as any wastes that are left at the site as part of site remediation.

As I have indicated, I have a conflict with the RPM meeting scheduled for Wednesday, April 23, 1997 where I will be in Puerto Rico advising governmental agencies and others on landfilling practices. I will be happy to answer any questions anyone may have about these comments upon my return which is anticipated to take place on Saturday, April 26, 1997.

Sincerely yours,

Fred

G. Fred Lee, PhD, DEE

GFL:djc
Enclosure

Comments on "Draft Risk Assessment Protocol"
for the UCD - DOE LEHR Superfund Site
Prepared by Weiss Associates
Dated March 15, 1997

Submitted by

G. Fred Lee, PhD, DEE
G. Fred Lee & Associates
El Macero, CA 95618
Ph: (916) 753-9630
Fx: (916) 753-9956

Submitted to

the Davis South Campus Superfund Oversight Committee
for the UCD DOE LEHR Superfund Site

April 19, 1997

Overall Assessment

The overall draft protocols for risk assessment presented in this document are technically invalid with respect to properly incorporating environmental chemistry into risk evaluation. As discussed herein, DOE has mistakenly assumed that the total concentration of a regulated constituent measured by the analytical methods used at the LEHR site thus far, is a measure of potential risk. Such an approach can readily lead to significant errors in reliably assessing risk. There has been a significant problem with LEHR site investigations where the DOE-UCD contractors and site management personnel have not properly incorporated environmental chemistry/toxicology into site characterization. Thus far, the approaches used have largely been a brute force chemical approach which fails to consider toxic, available forms potential impacts of site-associated constituents compared to the off-site/background or upstream constituents.

Further, the site characterization completed thus far has failed to properly consider the potential concentration of constituents that could be adverse in analytically measuring constituent concentrations. This has led to measurements of constituents where the concentrations reported are less than detection. However the detection limits were not adequate to detect potential problems. It is not appropriate to now ignore the problems with the inadequate detection limits and assume the only constituents of concern at the site are those that were measured above the detection limits used.

The inadequate planning and implementation of the site characterization by DOE and UCD which failed to incorporate bioaccumulation of hazardous chemicals and aquatic life toxicity in the discharge and receiving waters for LEHR site stormwater runoff has now left a large gap in the data base needed to properly characterize the risk to public health and the environment associated with stormwater runoff from the LEHR site. These problems were first pointed out to UCD and DOE in the summer of 1995 by DSCSOC when it became involved in the review of LEHR site investigation and remediation programs. Finally, through DSCSOC and the RPM efforts, the US EPA Region IX and ATSDR did conduct sampling of fish taken from Putah Creek which showed that, at one of the points where LEHR site stormwater runoff enters Putah Creek, the fish had bioaccumulated excessive levels of mercury and lead.

The proposed risk assessment protocols would have failed to detect this threat to public health since the concentrations of mercury in the stormwater runoff from the LEHR site was not properly evaluated with respect to receiving water bioaccumulation issues. This occurred even though it has been known for over 20 years that mercury at concentrations less than those reported in LEHR site stormwater runoff could bioaccumulate to excessive levels and be a threat to human health to those who consume fish with this level of mercury bioaccumulation. The DOE proposed risk assessment is fundamentally flawed with respect to considering environmental chemistry fate of constituents that could cause a constituent to be a greater hazard than had been predicted based on the analytical and study approaches used in the LEHR site investigation.

Another significant problem with these draft proposed risk assessment protocols is the failure thus far to conduct aquatic life toxicity tests in the stormwater runoff as well as in the receiving waters for the LEHR site stormwater runoff. Without such tests conducted over a several year period, it is not possible to characterize the risk that potentially toxic chemicals in stormwater runoff from the LEHR site, either alone or in combination with chemicals in the ambient waters, represent to aquatic life and other beneficial uses of the receiving waters for the runoff. Again, this deficiency in the study program was pointed out when DSCSOC first became involved in the review of UCD-DOE LEHR site activities in the summer of 1995. As of yet this deficiency in site characterization has not been addressed. Without this information, it is not possible to reliably characterize the risk of both regulated and unregulated chemical constituents in stormwater runoff from the LEHR site. Further, DOE's proposed risk assessment protocols are not reliable to characterize the hazard due to potentially toxic chemicals present in stormwater runoff from the site. It will take several years of data collection in order to develop the data base necessary to properly characterize the risk associated with potential toxicity in stormwater runoff from the LEHR site.

Another significant problem with these proposed risk assessment protocols is the approach identified for determining constituents of concern relative to the arena of potential constituents of concern at this site. A properly conducted risk assessment must consider the potential adverse impacts of the large number of currently unregulated compounds that could be present at the site as well as their transformation products. Plausible worst-case scenario evaluation approaches should be used for unidentified or unregulated constituents to assess the potential risk that they represent to public health and the environment.

Basically, DOE and UCD have thus far conducted a limited scope investigation of the potential hazards associated with the LEHR site wastes and UCD mismanaged waste chemicals. These proposed protocols for assessing risk now attempt to use the results of the limited scope evaluation compared to what could and should have been conducted to define risk. Such an approach is technically invalid and not protective of public health and the environment.

It is of great concern that DOE is now attempting to utilize the limited waste management unit and contaminated soil characterization studies that have been conducted thus far as a basis for developing a risk assessment where chemical constituents are being eliminated from being considered as hazardous based on some arbitrary cut-off limit. Both DTSC (Duncan Austin) and DSCSOC (Fred Lee) made it clear to DOE and UCD that the limited scope investigations that were then planned for each of the waste management units and the soils would not be suitable to determine that a chemical present at an area of the LEHR site was not a risk. The data available at this time on the characteristics of the waste management units should only be used to determine that there should be complete removal of all wastes and contaminated soils associated with the waste management unit. The existing database is not adequate to determine that a particular chemical is not present in sufficient concentrations and forms to be a risk to public health and the environment.

One of the key issues that has to be understood immediately is how DOE proposes to use the risk assessment in decision making with respect to remediation of waste management units and the associated soils. If DOE proposes to leave any wastes in a waste management unit or in the soils associated with the waste management unit at their current location based on the risk assessment results, then DOE must conduct a far more comprehensive, in depth investigation of the characteristics of each waste management unit and associated soils than has been conducted thus far. DOE cannot, as it is apparently planning to do, conduct superficial, exploratory studies of the characteristics of waste management units and then assert that since the risk found in such studies are less than some risk level, that the wastes and contaminated soils can be left in place as part of site remediation.

UCD management chose to dispose of wastes and manage campus hazardous chemicals at the LEHR site in a cheaper-than-real-cost approach as part of LEHR site activities. DOE is now trying to continue the cheaper-than-full-risk-evaluation approach for risk assessment. A properly conducted risk assessment must include evaluating plausible worst-case scenario situations and then developing appropriate remediation and monitoring programs that consider plausible worst-case situations for adverse impacts of the residual chemicals that are left at the site after site "remediation." This will require a significantly more reliable risk assessment approach than DOE has proposed in the draft protocols.

Specific Comments

Page 1-1 states that this Draft Risk Assessment Protocol applies only to DOE areas of responsibility. Does this mean that UCD will also prepare a Draft Risk Assessment Protocol for review? If so, this should be done immediately.

Page 1-2, under "Objectives," presents a series of bulleted items. One of the most important issues, however, is missing - namely to address the human health risk evaluation for unregulated chemical constituents and from regulated chemical constituent transformation products that represent a risk to human health at a complex chemical or hazardous chemical site such as the LEHR site. There can readily be a substantial number of constituents present in wastes and contaminated soils at the LEHR site that represent hazards to public health and the environment that are not now being considered in the proposed risk assessment approach. A properly conducted risk assessment must develop protocols that provide an assessment of the potential risks that could occur from these chemicals to public health and the environment. The approach that should be followed is to assume a plausible worst-case scenario situation for unregulated chemicals and regulated chemical transformation products at each of the waste management units and areas of contamination.

Page 1-3, under the bulleted items for "protocol attempts to establish:" the first bulleted item states, "...with respect to ecological contaminants of potential concern;". Again, since only a small number of chemical constituents that are in use are regulated with respect to an ecological impact, the ecological risk assessment protocols must include consideration of plausible worst-case impacts from chemical constituents that could be present in the waste management units or contaminated soils, either as original constituents deposited in the area/transported to an area or their transformation products.

Page 2-1 under the first full paragraph states that the data will be reviewed and "...errors will be corrected or removed from the database before proceeding...". Hopefully, finally the data reports that have been developed at the LEHR site by UCD and DOE contractors will now be corrected for the obvious errors that have been found that now exist in the databases. Further, since my previous reviews of the data reports only dealt with detecting obvious errors in data reporting, there is need for a critical review of all data for internal consistency and appropriateness to detect less obvious, but significant errors.

Page 2-2, in section 2.1.2, paragraph two, states that the detection limits for various measured parameters will be used in evaluation of constituents of concern (COC) from each operating unit (OU). The data for each parameter should be carefully evaluated with respect to whether the detection limits were adequate to detect potential problems. For a number of parameters, such as chlordane and mercury, the detection limits used were not adequate to detect potential problems. Therefore, using non-detect data to screen out constituents of concern is not a reliable approach to determine whether there are potential problems associated with a constituent.

Page 2-2, last paragraph, states that constituents will be eliminated as potential COCs where the chemical constituents are detected at higher levels in upstream Putah Creek sampling locations. That approach is not technically valid. It assumes that the adverse impact of a constituent is proportional to concentration. It is well-known that is not a valid assumption for many constituents. The adverse impact of a constituent is proportional to the available forms of the constituent in a site-specific situation. Materials added from UCD/DOE's operations associated with the LEHR site could be in toxic, available forms while the upstream constituents are in nontoxic forms. The analytical methods used do not necessarily measure only available forms of constituents. A properly developed risk assessment must consider the toxic available forms of constituents and not, as proposed herein, focus only on increased concentrations of total constituents. The proposed approach is technically invalid.

One of the significant errors that was made and still has not been corrected, even though it was pointed out almost two years ago, is that the LEHR studies have not included aquatic life toxicity measurements to screen for toxic, available forms of regulated constituents as well as unregulated constituents in stormwater runoff from the LEHR site. The recently-released ATSDR data on mercury and lead in fish taken from the area where LEHR site stormwater and UCD's wastewaters are discharged to Putah Creek demonstrates the errors that were made by DOE and their contractor Dames & Moore (while they were a contractor for DOE at the LEHR site) in establishing the study approach where a technically invalid assessment was made for when to make bioaccumulation studies of aquatic life for potential impacts of constituents derived from the LEHR site on public health.

Basically, the overall proposed approach for identification of constituents of concern is not adequate to protect public health and the environment. There can readily be adverse impacts due to constituents which are excluded by this proposed protocol which are adverse to public health and the environment. A credible risk assessment protocol must address these issues.

Page 2-3, under section 2.1.2.1 "Use of Qualified Data," before any data is rejected as proposed, the potential consequences including the data in the evaluation of risk should be conducted to consider plausible worst-case situations.

Page 2-3, under section 2.1.2.2. "Evaluation of Tentatively Identified Compounds" (TICs), I have seen no information on TICs. Has someone critically reviewed the TIC data to see if there is a pattern that should be followed up on to identify other potential constituents of concern? While the statement is made that the evaluation will follow RAGS, a summary should be included here as to what will actually be done so that the reviewers can examine how well DOE understands the issues that must be addressed.

Page 2-3, under section 2.1.2.3 "Elimination of background chemicals," it states, "Chemicals that were detected in site soil, ground water and surface water will be evaluated against background data where background data are sufficient." This section also states, "Chemicals whose RME concentration is not greater than background will not be carried forward through the risk assessment." This is another technically invalid approach which ignores basic principles of environmental chemistry. As discussed above for chemicals in Putah Creek, it is not reliable to assume that the toxic, available forms of a constituent at the LEHR site is proportional to concentration. Chemical constituents exist in a variety of forms, only some of which are available. A concentration of a constituent associated with the hazardous chemical sites, such as the LEHR site that is not different than background for off-site areas, can be hazardous if it is in a toxic, available form while the background is in a non-toxic form.

As far as I can find, the initials "RME" are not defined where it should be, i.e. at its first use.

Page 2-4, states,

"An arbitrary cut off frequency of 2% was selected to remove chemical data that may have been reported with a detected concentration due to human error, or which are isolated detection and not representative of a OU-wide COCs."

This is, as stated, an arbitrary approach and is unacceptable in a properly conducted risk assessment. Before any chemical that has been detected with appropriate detection limits is "removed" from further consideration, a plausible worst-case scenario evaluation must be made of the potential risk to public health and the environment associated with such removal.

Page 2-4, section 2.1.3.1 "Definition of Surface vs. Subsurface Soil," states that a three foot below ground surface (BGS) depth will be used to distinguish between surface and subsurface soil. Three feet is not adequate to protect future users of the LEHR area and property owners/users near the LEHR area from potential adverse impacts of residual chemicals that could be left at the site. Deep rooted vegetation can readily translocate constituents in soils below three feet. Further, construction activities at the site can readily bring to the surface soils that are deeper than three feet. It is sometimes argued that use restrictions can limit the hazards of residual chemicals left at a hazardous chemical site after remediation that could readily be brought to the surface of the soil through future construction activities, etc. In principle, use restrictions could limit construction activities at the site and, thereby, restrict the transport of residual chemicals from the subsurface to the surface. However, since the many of the chemicals of concern will be a threat forever, it is unlikely that future owners/users of the property, and especially UCD, will be able to reliably manage the activities that take place at the site to prevent the transport of hazardous regulated chemicals as well as unregulated hazardous chemicals to the surface and thereby potentially exposing on-site as well as off-site people and wildlife to hazardous conditions for as long as the wastes represent a threat. Because of the unreliability of the use restrictions, it is essential that more than a three foot barrier be provided between clean soils and underlying contaminated soils.

Page 2-4, last paragraph, defines "RME." This should be defined the first time it is used in the text, not several pages after its first use.

Beginning on page 2-5 and continuing on page 2-6 is a discussion of determination of background. The approach taken with the soils is not necessarily valid. Determining background with respect to establishing clean up objectives should not be approached on an area-wide statistical approach as proposed. This requires a critical examination of the data with respect to such issues as gradient analysis, adequacy of the database along gradients, etc. The appropriate clean-up objective for a constituent at a particular waste management unit should be established on a site-specific basis. These issues will need to be discussed further.

While determination of background information for groundwater is not included, there are significant issues that need to be addressed, such as the adequacy of the monitoring program that has been established thus far for so-called background monitoring wells in light of the variability of the composition of groundwaters in the region. The high variability of the composition of groundwaters makes the mechanical approach toward a statistical comparison that has been used at the LEHR site by previous DOE contractors an unreliable approach for establishing whether a groundwater is polluted by LEHR site waste. Again, as with soils, it is not appropriate to take the mechanical approach to establishing background that can be used to determine whether a groundwater is polluted by LEHR site wastes needs to be remediated.

The discussion on establishing surface water background is inappropriate for a variety of reasons primarily related to the inadequate database development approach that was established by DOE and its contractors that has persisted for the past almost two years, even though the inadequacy of the database and the unreliability of the approach was pointed out in the summer of 1995. It appears that there is little need to establish a background concentration on Putah Creek waters since the background is variable and what exists at one time does not apply to the next time. Certainly, it is totally inappropriate to apply a statistical analysis as is apparently planned.

No information was provided on Putah Creek contaminated sediment issues. This will also need to be addressed by LEHR site clean-up where there will be questions about background that will need to be resolved.

A key component of establishing background is how the background data will be used in decision-making to establish clean-up. UCD - DOE should provide several scenarios representing plausible situations that could occur at this site for various types of waste management units and then use the background establishment approach that they propose to use to discuss how they would proceed to determine the need for remediation. With this information, it would be possible to determine whether the approaches that are proposed are technically valid.

Overall, the approach for establishing background is apparently not valid. DOE needs to start over on this topic area to address the issues that are raised herein.

Page 2-7, under the third bulleted item in the lower half of the page, describes the area 135 to 143 feet bgs as "Clay with some silt." I understand that UCD has found some sandy layers in this so-called clay area. This description should be modified to reflect that situation. Any discussion of the geological strata below LEHR must include the second major aquifer under the site (HSU-4).

Page 2-8, first paragraph, fails to include the new information on HSU-3, namely that it is not a 90-foot thick clay unit, but contains at least one and possibly more groundwater bearing layers. A discussion must be included on page 2-8 of the lack of information on HSU-4. HSU-4 is an important aquifer that both UCD and DOE have tended to ignore. No further documents should be produced associated with the LEHR site that do not fully recognize HSU-4 as likely being contaminated by LEHR site wastes and that there is limited information available on the characteristics of this aquifer and the pollution that has occurred thus far.

Page 2-8, mid-page, states, "Ground water in HSUs 1 and 2 has been impacted by site activities...." Also, groundwater in HSUs 3 and 4 are likely impacted and a statement should be added to properly describe the situation.

Page 2-8, next-to-last paragraph, should mention the recent court decision which allows the base flow in Putah Creek to be maintained at a higher level than has occurred in the past through forced releases of water originally devoted to irrigation for aquatic life habitat and maintenance.

Page 2-9 under 2.2.2 "Exposure Scenarios," does not address an exposure scenario that has occurred in the past and could still be occurring, namely surface water discharge to Putah Creek where chemicals that are now unregulated are known to be present at a hazardous level and will become recognized as hazardous chemicals in the future. This is a plausible situation that could readily occur that needs to be considered, especially in light of the recent situation where fish in Putah Creek have been found to contain excessive concentrations of mercury and lead. At this point, it is not possible to rule out LEHR stormwater runoff as a source of these chemicals.

Further, this listing of exposure scenarios is based on human health and does not include wildlife. For example, many times when I am visiting the LEHR site, there are jack rabbits in the dog pen area. Has anyone examined the jack rabbits to see whether they have an elevated concentration of hazardous chemicals and radioisotopes? They should have been analyzed many years ago. Further, to my knowledge there still has been no credible studies of whether the vegetation associated with plants and trees which have their roots into the wastes are translocating hazardous chemicals from the waste management unit to the surface and then exposing humans and wildlife to these hazardous chemicals. As discussed earlier, the approach that must be used in establishing exposure scenarios is plausible worst-case.

On page 2-9, under "Fate and Transport" for airborne particles, the issue should be expanded to include consideration of particle size. When evaluating the hazard of an airborne particle from OUs compared to off-site-derived particles, total particle concentration should not be used. Specific particle size information should be used since it is well-known that particle size influences hazard.

While page 2-10 mentions that particle size information should be considered where data exists from previous investigations, because particle size data has not been developed does not mean that particle size information can be ignored. If there is any reason to believe under plausible worst-case scenario evaluation that particle size could be important, then the data will have to be generated. Just because the studies that were set up by DOE, UCD and its previous contractors did not properly consider risk assessment issues does not mean that these issues can now be ignored.

Page 2-11, upper part of the page, discusses the approach that will be used to establish the exposure pathways of OUs to groundwater where it states that consideration be given to pollution of groundwaters above MCLs. As discussed in previous correspondence, this is not a valid approach for a variety of reasons, including the fact that only a small number of the potentially hazardous chemicals managed at the LEHR site have MCLs. Consideration must be given to the fact that unregulated hazardous chemicals exist in the waste management units and contaminated soils and that these are a threat to current and future generations' use of groundwaters. The approach I recommend is to use a hypothetical, unregulated chemical scenario where, at some time in the future, a chemical will be found in waste management units or contaminated soils that are left at the site which is 100 times more hazardous than vinyl chloride and is as transportable through the aquifer system as vinyl chloride.

The second reason the proposed approach involving an exceedance of an MCL as a critical value is invalid is the fact that it fails to recognize that there are natural pollutants, such as chromium, both on-site and off-site. It could be that the off-site groundwater wells would be just under the MCL for chromium if UCD had not disposed of its chromium wastes in an improper manner at the LEHR site. The additional waste components derived from the disposal, however, would cause an off-site groundwater well which would normally be below the MCL and be considered safe to be above the MCL and, therefore, hazardous. In evaluating whether pollution has occurred by LEHR site waste management units, it is mandatory that consideration be given to whether the release of constituents from waste management units to groundwaters has used up important assimilative capacities of the aquifer system for natural or pollutants derived from the activities of people, such as agricultural activities that are not now regulated, and, therefore, are permissible. However, the disposal of the wastes at the LEHR site are regulated so there is no impairment of the beneficial uses of on-site and off-site groundwaters. Using up some of the aquifer's assimilative capacity for acceptance of unregulated constituents is an impairment of use that must be considered. The section on groundwater issues needs to be redone to more properly consider regulatory as well as technical issues associated with the pollution of groundwaters by LEHR site wastes.

Another factor to consider is that MCLs can change, and for a number of constituents, such as arsenic, it is well known that the MCL will be decreased by at least one order of magnitude. A properly conducted risk assessment must consider this type of situation.

With respect to modeling transport in groundwater systems, more information is needed before it is possible to judge whether the proposed approach outlined on page 2-11 is appropriate and valid. It is important for DOE to understand that putting in a few sentences now about what in general would be done without providing specific discussion of issues and details with examples of actual situations does not give DOE the license to claim at a later date that this was approved by the group as part of reviewing this draft risk assessment. Often, there is too little information provided in this draft to judge the validity of the approaches being proposed.

I do not understand the statement that is made in the first full paragraph on page 2-11 that, "The results of that analysis indicate that only nitrate, of the five indicator compounds selected for analysis, is likely to impact ground water at levels above the MCL." This means that the only constituent that has polluted groundwaters at the LEHR site is nitrate. There is something fundamentally flawed with the approach that is used to develop this type of a result.

On page 2-13, under section 2.4 "Calculation of Action Levels for Chemicals," further information is needed before I can understand and accept the approach indicated.

Page 3-1, under section 3.1.1.1 "Identification of Media of Environmental Concern," states that the same data set that is used for human health evaluation can be used for ecological evaluation. Unfortunately, DOE, UCD and DOE contractors did not set up the ecological evaluation properly. Therefore, the data set needed to properly assess ecological risks in many cases does not exist. For example, there is still no aquatic life toxicity data in stormwater runoff waters or Putah Creek waters. Without such information it is not possible to conduct a meaningful ecological risk assessment for hazardous chemical sites, such as the LEHR site, as was pointed out almost two years ago. UCD - DOE chose not to address these issues then and as a result may not be able to proceed with a proper ecological risk assessment until an adequate database is established.

Page 3-2 states that groundwaters will not be considered as a source of constituents that could cause ecological damage. This approach is not valid since groundwaters will have to be pumped and treated and, therefore, brought to the surface. While on the surface either through a surface discharge or through management, mismanagement could occur which would result in the release of constituents to the environment that cause ecological harm. This should be considered as one of the potential pathways of harm to ecosystems associated with the LEHR site.

On page 3-2, mid-page, is a discussion of stormwater issues. This discussion is significantly deficient compared to the situation that exists. UCD still has a channel cut through the top of Landfill No. 3 where every time it rains, wastes that are exposed in the base of this channel are washed by stormwater. Further, as part of constructing that channel, there readily could be hazardous chemicals and radioactive wastes scattered around the countryside near the area where the excavated landfill cover and waste materials were deposited. The section on stormwater needs to be redone to more properly discuss the situation that has and continues to exist at the LEHR site. For example, the fact that DOE and UCD planned, executed and apparently continue to execute an inadequate stormwater runoff monitoring program is now going to be the primary stumbling block to developing a proper risk assessment. The risk assessment for stormwater issues may have to wait several years until a properly implemented program is conducted and an adequate, reliable database is developed. It does not exist now.

An example of this is the situation that has occurred with mercury and lead with respect to the stormwater runoff from the LEHR site. While I have not gone back to check to see if mercury and lead have been analyzed in the stormwater runoff samples, I believe they have. If they have not, they should have been. The results of such analyses would have shown, however, that there would be no predicted problems in Putah Creek. However, as I pointed out when I first reviewed the data reports from the LEHR site in the summer of 1995, the studies were fundamentally flawed with respect to addressing bioaccumulation issues. DOE and its contractors, based on the RI/FS, did not understand these issues where they stated there was no need for bioaccumulation studies. It has been well-known since the 1960s that bioaccumulation is one of the primary modes of exposure of people to hazardous chemicals associated with surface water situations.

The recent ATSDR data on fish tissue analyses show that there is now, likely has been and likely will continue to be excessive concentrations of mercury and lead in fish near where part of the LEHR site stormwater enters Putah Creek. It is not possible at this time to rule out the fact that LEHR site-derived stormwater runoff is a contributor to the lead and mercury problems in fish in Putah Creek near the ATSDR Site 1 location. This exposure scenario must be considered. Further, even though ATSDR - US EPA in their initial sampling did not find other constituents of concern, there are problems with some of the analytical methods used compared to US EPA guidance values for excessive bioaccumulation. In addition, there could readily be unidentified hazardous chemicals from the LEHR site in stormwater runoff that are bioaccumulating in fish representing a hazard to public health and the environment which were not considered in the ATSDR study.

Page 3-2, the bottom of the page, indicates that the same approach that is used for human health of considering surface soil from 0 to 3 feet will be used for ecological risk assessment. That approach is not valid. The potential for ecological damage from hazardous constituents below 3 feet is even greater than that for human health due to translocation of constituents by deep-rooted plants to the surface.

Page 3-3 states, "The RME concentrations for COCs detect an ecologically significant media at the site will be determined identically to the methodology in the human health evaluation." It is not clear what that means. Further, as discussed herein, there are significant problems in the proposed approach for human health evaluation. This should be discussed with specific examples to eliminate the ambiguity of what is proposed to be done.

Page 3-3, third paragraph, states,

"If no organic COCss [sic] are identified and concentrations of inorganic constituents are at or below background concentrations for a particular media, that media will be dropped from further consideration in the exposure pathway assessment for ecological receptors for the OU."

That approach is not technically valid and assumes that the analytical program carried out thus far by UCD and DOE has identified and characterized all of the potentially hazardous constituents in the OUs that could be adverse to ecosystems. The facts are that there are probably only a small part of the constituents of concern that could be adverse to ecosystems have been identified. As discussed with human health risk assessments, there is need to develop an appropriate surrogate for unregulated chemicals in assessing ecological impacts. The surrogate should be considered to be toxic at about 1 nanogram/L and be conservative with respect to transport and transformation except for dilution that can occur. There could readily be constituents of that type that have not yet been identified in various waste management units at the UCD LEHR site.

Page 3-3, bottom of the page, sets the distinction between surface soil and subsurface soil as three feet. This should be decreased to six feet based on the fact that there are a wide variety of processes that can take constituents buried at three feet to the surface where they could have a adverse impact on ecosystems.

Page 3-4, first paragraph, is a restatement of what has been said earlier on constituents of concern with respect to organics and inorganics. The same comments apply to this inappropriate approach.

Page 3-4, fifth paragraph, states that stormwater is collected in a drainage system in the area of the Southwest Trenches. It is not clear that this is necessarily true, especially for the Southwest Trenches that are located near the southwest corner of the LEHR site. Stormwater runoff ponds in that area above existing waste management units. This ponding has lead to greater groundwater pollution than would be occurring otherwise because of the increased hydraulic loading on the waste management unit. DSCSOC suggested that this problem be corrected almost two years ago, and it has still not been addressed.

The statement in that same paragraph about

"Storm water in the eastern portion of the LEHR site, where the landfills and other UC Davis disposal units are located, percolates into the soil (DOE, 1996), with the exception of a stormwater ditch at the eastern edge of landfill #3, which discharges to Putah Creek."

is not true. Whoever wrote and reviewed this section has not reliably investigated the stormwater flow patterns at the LEHR site. These sections need to be rewritten to properly reflect what has been known for many months about the stormwater runoff patterns at the LEHR site.

DOE, UCD and their contractors did not properly investigate stormwater runoff patterns in connection with establishing the stormwater runoff monitoring program that has been conducted for a number of years at the LEHR site. It was not until last summer that, as a result of a walk over the property by the RPMs and DSCSOC representatives, it was discovered that an obvious major storm drain is present on the south side of the LEHR site which drains stormwater from mid-LEHR site to Putah Creek. This stormwater includes runoff from several waste management areas. This drain was not sampled. Whether this sampling is being done now is still unknown since UCD has failed to provide a reliable stormwater runoff monitoring program for the LEHR site. This is a derelict situation with respect to UCD's protection of public health and the environment that must be immediately corrected.

The description of the LEHR site being outside the 100-year flood plain which is bounded by a Putah Creek levee should be amplified to mention the fact that levees are not always protective as exemplified by the New Year's Day flooding that occurred in Central California where many levees gave way.

Page 3-5, fifth paragraph, states that Putah Creek is an "...intermittent stream...." Below Old Davis Road for a considerable distance, Putah Creek is not an intermittent stream; it is an effluent-dominated stream for some distance downstream of the UCD campus wastewater discharge.

Page 3-6 should mention that Dr. Peter Moyle and his graduate students have conducted a fish characterization study on Putah Creek.

Page 3-9, item 4 states, "No exposure route exists at the point of contact." "Exposure route" should be defined as plausible worst-case scenario situations.

Page 3-9, second full paragraph, must include a complete consideration of the aqueous environmental chemistry of the constituents of concern that could influence its fate and impacts, not just those parameters listed.

Page 3-10, may not consider translocation of constituents from deeper in the soils to the surface through the plant structure. This should be one of the exposure pathways that is considered.

Page 3-11, next to last paragraph, states, "As the stressors are chemical in nature...." There may be biological stressors associated with UCD's past waste disposal in these landfills where cyst-forming protozoans are present in the wastes that represent a threat to public health and the environment.

On page 3-15, one of the bulleted items states, "Be diagnostic of the pollutants of interest." It is important to clearly distinguish between "pollutants," i.e. those that have adverse impacts, and "chemical constituents" which are present which may or may not have an adverse impact, either because of concentrations, duration of exposure or chemical forms.

On page 3-15, in the second full paragraph, it appears that the approach that is proposed is based on comparing ARARs to concentrations found or predicted. Such an approach can, for some constituents, be over-protective and for others, under-protective. For regulated constituents, this approach apparently ignores the environmental chemistry of a constituent and its availability. For unregulated constituents for which there are no ARARs, this approach ignores potentially significant ecological impact due to unregulated chemicals or combinations with other regulated chemicals or unregulated chemicals.

Page 3-16, section 3.2.4.1, devoted to a discussion of the use of ambient water quality criteria, caution must be exercised in the use of these criteria to judge ecological impacts. I was involved as a peer reviewer for the US EPA in developing the water quality criteria development approach as well as certain of the criterion documents. These criteria tend to be over-protective in many situations. There is also the fact that many of them were developed over 10 years ago and, even if updated, have not considered the new information that is available, for example, on chromium VI toxicity. This past week I presented a paper at an American Chemical Society national meeting held in San Francisco devoted to chromium VI regulatory issues. A copy of the poster items used in this paper is available from my web site (http://members.aol.com/gfredlee/gfl.htm). The primary thrust of this paper is that chromium III and VI are not adequately regulated today based on what is known about chromium VI toxicity and their aqueous environmental chemistry. The use of chromium III and VI ARARs will not be protective. The mechanical use of water quality criteria as apparently proposed could lead to an incorrect assessment of ecological impacts from LEHR site waste derived constituents.

Page 3-17 in the third full paragraph, states,

"The assumption is made that adequate ARARs or toxicity criteria will be available for the representative species selected to evaluate ecological risk without conducting bioassays or toxicological studies for the site."

This is an inappropriate assumption from several perspectives. First, as discussed herein, it does not consider the unregulated constituents which are certainly present at the site that could be of ecological significance. Further, there certainly are chemical constituents at the LEHR site which are in non-toxic, non-available forms. Regulating them, assuming that they are toxic as predicted by the ARAR, is technically invalid.

Page 3-17, lower half of the page, third bulleted item, states that the National Oceanic and Atmospheric Administration (NOAA) sediment criteria are to be used. There are no NOAA sediment criteria. NOAA has never adopted such criteria. There are Long and Morgan co-occurrence values. Those responsible for NOAA's national sediment assessment program find that the Long and Morgan values are not reliable. This is to be expected since the Long and Morgan values are based on co-occurrence, which is a technically invalid approach for assessing the potential impacts of chemical constituents on aquatic life associated with sediments. I have discussed this issue in several papers available as downloadable files from my web site. The statement that no bioassays will be conducted reflects an inappropriate approach. Before conducting the risk assessment, appropriate bioassays must be conducted of water and sediments. A credible risk assessment cannot be developed without conducting such tests on LEHR site stormwater runoff and receiving waters over a several-year period.

There are no reliable sediment concentration data as well as standards by which to evaluate such data; sediment impacts have to be based on toxicity tests or site-specific assessment of bioaccumulation. Field testing will have to be done to develop a credible risk assessment from past and current adverse impacts of LEHR site stormwater runoff.

I need to review the California DTSC applied action levels for protection of aquatic life before I can judge whether these are appropriate.

Page 3-19, the "Assessment of Ecological Risk," suffers from many of the deficiencies that have been discussed in these comments. They will not be repeated here. This assessment has to consider the issues that have been raised in these comments if it is to be credible.

The tables and charts presented at the end of this section contain many of the same problems that have been discussed in these comments; I will not repeat the comments here. They do need to be modified to properly consider the full range of risks that are associated with the LEHR site wastes.

In checking the reference list on pages R-1 to R-3, I find some of the references cited in the text are apparently not listed in this list. If my preliminary assessment is true, there has been inadequate proofreading that should not have occurred. Those responsible for developing documents of this type must take the time to properly proofread to be sure that the references cited in the text are, in fact, listed in the reference list. Part of the problem may be with the system used for listing references compared to that used in the text. DTSC 1996 should be the first thing that appears in the reference list, not Cal EPA, unless it is listed as Cal EPA in the text.

Overall Assessment

One of the issues that has to be addressed in any human health and ecological risk assessment in connection with determining the degree of public health and environmental protection associated with a hazardous chemical site such as the LEHR site is the quality of the on-going monitoring program that will be conducted after waste management unit--site remediation. The LEHR site will require ad infinitum high-quality monitoring to ensure that regulated chemicals that are not now considered hazardous as well as the unregulated chemicals that have become recognized as hazardous, do not become recognized as a significant cause of public health and environmental harm. In order to determine the degree to which it is possible to now limit the attention given to the potentially hazardous unregulated chemicals, the potential characteristics of the ongoing monitoring program after remediation--site closure that will be conducted by UCD and DOE need to be defined. If this program is going to be minimal, as is typically the case today, then much further attention must be given to the unregulated chemicals at this time as part of site remediation to minimize the risk to public health and the environment that will occur associated with any residual constituents left at the site.

Overall this Draft Risk Assessment Protocol takes the conventional approach which for a complex site such as the LEHR site will not likely be protective of public health and the environment. This risk assessment document needs to be redone and expanded to address the issues that have been raised in these comments.

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