G. Fred Lee
Considerable confusion exists today on the appropriate approach to follow for regulating urban area use of pesticides in order to protect stormwater runoff receiving water aquatic life from pesticide caused toxicity. This problem arises in part from the fact that animal and plant pests are significantly adverse to urban dwellers' structures and properties. Pesticides, including herbicides are effective for controlling the adverse impacts of urban pests. However, current pesticide regulatory approaches associated with pesticide registration and use labeling do not necessarily eliminate pesticide caused toxicity to some forms of aquatic life in stormwater and fugitive (irrigation) water runoff from residential and commercial properties. Stormwater runoff from urban areas throughout the State and in many other parts of the nation and in other countries have been found to be toxic to some forms of aquatic life such as zooplankton Ceriodaphnia. This toxicity has been found to be due to organophosphate pesticides (OP) principally diazinon and chlorpyrifos. Current evidence indicates that labeled use of OP pesticides leads to surface water toxicity during stormwater runoff events. The key issue that needs to be addressed as part of developing a regulatory approach for urban OP pesticide toxicity is the water quality significance of this toxicity to the beneficial uses of the receiving waters.
At this time the OP pesticide toxicity associated with urban stormwater runoff is of concern with respect to potential adverse impacts to certain zooplankton species (Ceriodaphnia-like organisms). While there is no doubt that certain zooplankton species' populations are adversely impacted by urban area stormwater runoff OP pesticide caused toxicity, it is unknown at this time whether this toxicity is significantly adverse to fish populations through impacting the availability of zooplankton food for larval fish. This is the critical area that must be evaluated through site specific studies which assess the spectrum of zooplankton organisms that are adversely impacted by OP pesticide toxic pulses that occur with each urban stormwater runoff event. Once the types of zooplankton impacted by OP pesticides are known, then site specific evaluations need to be made in the receiving waters for the urban stormwater runoff which determine the magnitude of zooplankton population impacts and the significance of these impacts on higher trophic level organisms through restrictions in their zooplankton food supply. Of particular concern is whether reducing or eliminating zooplankton populations with a sensitivity to that of Ceriodaphnia to OP pesticide toxicity sufficiently restricts larval fish food to impact the water quality and ecological characteristics of a waterbody.
The current risk assessments for diazinon and chlorpyrifos toxicity that have been developed by pesticide companies and others have not adequately addressed many of the key issues that need to be addressed in order to determine whether OP pesticides present in urban stormwater runoff at potentially toxic concentrations are significantly adverse to the beneficial uses of the receiving waters for the stormwater runoff as well as the aquatic and terrestrial ecosystems associated with these waters. At this time there is a poor understanding of the full range of organisms that are impacted by OP pesticide toxicity in receiving waters for urban stormwater runoff. Further the actual zooplankton and larval fish population dynamics associated with urban stormwater runoff pesticide toxicity has not been adequately investigated. The macrocosm studies which have been used to claim that the OP pesticide toxicity is of limited significance to fish populations do not provide adequate, reliable information on this issue that can be extrapolated to the range of conditions where there is appropriate concern about OP pesticide toxicity associated with urban stormwater runoff.
There is need to provide guidance to regulatory agencies, commerce, industry, environmental groups and the public on how to determine whether the OP pesticide toxicity associated with urban stormwater runoff and fugitive irrigation runoff is of sufficient magnitude, duration, areal extent to adversely impact zooplankton species that are essential components of larval fish food. It is suggested that the state of California Water Resources Control Board and the regional boards appoint an expert panel to develop the guidance needed to assess on a site-specific basis, the water quality significance of urban stormwater runoff OP pesticide toxicity. This expert panel would develop guidance on the types of site specific studies that are needed to define the water quality - use impairment significance of urban stormwater runoff associated OP pesticide toxicity. The overall approach should follow the development of information to formulate a site specific ecological and water quality risk assessment associated with OP pesticide use in urban areas.
The risk assessment information should provide the technical base that regulatory agencies can use to develop pesticide toxicity control programs without significant unnecessary restriction on pesticide use beyond that needed to protect the designated beneficial uses of receiving waters and downstream waters for urban area stormwater runoff. This information when coupled with the other components of the pesticide regulatory process will ultimately lead to an appropriate balance between the use of pesticides in the urban environment and their impacts on the beneficial uses of receiving waters for urban area stormwater runoff.
There will be need for substantial expensive multi-year laboratory and field studies to provide the technical information base needed to properly manage urban area stormwater runoff OP pesticide toxicity. It is suggested that the expert panel formulate an approach which would specifically address the mechanism for developing the funds that are needed to conduct the necessary laboratory and field studies. The funding for these studies should be derived from the pesticide companies, pesticide formulators, applicators and the public who uses pesticides for urban pest control, i.e. those who benefit from pesticide use. Failure to provide the necessary funding should lead to severe restrictions on the use of OP pesticides in the urban environment that lead to stormwater and fugitive irrigation water toxicity in the receiving waters for the runoff. The burden of proof on the appropriate continued use of urban pesticides should be shifted from the environment to those who wish to sell, apply and use pesticides in urban areas where stormwater runoff from the areas of use leads to receiving water toxicity.
Summary of Issues Pertinent to
Regulating Bioaccumulatable Chemicals
Summary of Issues Pertinent to
G. Fred Lee, PhD, DEE and Anne Jones-Lee, PhD
G. Fred Lee & Associates
El Macero, CA 95618
PH: (530) 753-9630
FX: (530) 753-9956
From September 11-13, 1996 the US EPA held a National Sediment Bioaccumulation Conference in Bethesda, Maryland devoted to a selected review of the current state of knowledge on the regulation of chemical constituents present in aquatic sediments that tend to bioaccumulate to "excessive" amounts in aquatic organisms. The speakers at this conference were selected by the Agency.
The topic of bioaccumulation of chemicals from water and sediments is an area in which the senior author, Dr. G. Fred Lee, has worked since the mid-1960s. He has been particularly concerned about developing reliable approaches for regulating chemical constituents in sediments that could lead to excessive bioaccumulation of these constituents in higher trophic-level organisms that would impair the "water quality" of the waterbody in which the organisms and sediments are located. In the 1970s as part of the work that Dr. Lee's associates and he did on the Corps of Engineers Dredged Materials Research Program in developing dredged sediment disposal criteria, they specifically addressed the issue of how to regulate chlorinated hydrocarbon pesticides, PCBs and mercury in sediments that could be bioaccumulated directly from the sediments or through sediment water exchange from the water that would lead to excessive bioaccumulation in higher trophic-level organisms. At that time, it was concluded that there was no reliable way to predict the amount of bioaccumulation that would occur in higher trophic-level organisms based either on water or sediment concentrations of the bioaccumulatable chemicals.
A review of these issues and the authors' subsequent experience in this topic area has been published by Lee and Jones (1992) and Lee and Jones-Lee (1994). As discussed in these papers, since it is not possible to predict bioaccumulation that will occur in higher trophic-level aquatic organisms associated with a particular concentration of a potentially bioaccumulatable chemical in a waterbody's water or sediments, the authors recommend that the only way to reliably address this issue is to actually measure the bioaccumulation that occurs in order to determine whether there is, in fact, a water quality problem due to the excessive concentrations of chemical constituents in the aquatic sediments of a region.
The US EPA National Sediment Bioaccumulation Conference provided an opportunity to become familiar with the current state of knowledge on sediment bioaccumulation issues. Presented herein is a summary of the key issues that were discussed at the US EPA National Sediment Bioaccumulation Conference that are pertinent to developing technically valid, cost-effective approaches for managing chemical constituents present in aquatic sediments that tend to bioaccumulate in higher trophic-level organisms, either impairing the organism populations or causing these organisms to be considered "hazardous" for use as food by humans and/or wildlife. This discussion presents a synopsis of information presented by various speakers at the conference as well as the authors' many years of experience working in this topic area.
This discussion has been prepared as a background document that can provide guidance to the approaches that should be used in developing the Sacramento River Watershed Toxics Control Program. Bioaccumulation of potentially hazardous chemicals has been selected by the stakeholders in this watershed-based water quality management program as one of the major areas of concern. The Toxics and Monitoring Subcommittees of this program are in the process of formulating programs designed to address "toxics" issues. Specific guidance is provided herein on how bioaccumulation should be incorporated into this program that is based on current knowledge of sediment and/or water higher trophic-level aquatic organism bioaccumulation issues. This guidance can also be used for many other waterbodies and their respective watersheds to develop programs that appropriately formulate approaches for determining whether excessive bioaccumulation is occurring and, where found, the development of control programs to control its occurrence.
Laboratory Measurement of Bioaccumulation
It is possible to measure using aquarium-type tests and contaminated sediments the amount of bioaccumulation that will occur in benthic organisms (worms). It is not possible, however, to translate the concentrations of contaminants in sediments or the concentrations in benthic organism tissue to the concentrations in fish and other higher trophic-level organisms in real world situations. The sediment bioaccumulation measurements tend to significantly over-estimate the real bioaccumulation that will occur in higher trophic-level organisms in ambient waters.
Bioaccumulation Factor (BAF) or Biota-to-Sediment Accumulation Factor (BSAF) are highly site-specific and cannot be reliably extrapolated from one site to another or even at one site upon significant changes in the characteristics of the sediments associated with sediment remediation programs. Bioaccumulation factors from water and/or sediments are gross over-simplifications of the real world situation. The typical bioaccumulation factors that were used in the US EPA water quality criteria development (1987 "Gold Book") tend at many sites to over-estimate, in some cases by orders of magnitude, the bioaccumulation that will occur in real world situations in higher trophic-level organisms.
Biokinetic (Food Web) Modeling of Bioaccumulation
While it is possible to develop (curve fit) biokinetic models that will track to some extent the bioaccumulation that occurs in a particular waterbody for a particular type of organism and chemical, these models have limited predictive capabilities with respect to determining the degree of bioaccumulation that will occur in higher trophic-level organisms after remediating sediments to a certain extent. While these models simulate more closely than a simple two-black box or three-black box bioaccumulation sediment accumulation factor, they still do not properly address to any significant degree the highly heterogenous nature of particles in sediments and the absolute as well as relative binding capacity of each major type of particle.
It should not be assumed that the highest concentrations of the constituent in sediments necessarily leads to the source of constituents that bioaccumulate. Those constituents that occur in highest concentrations in sediments may be more tightly bound to particles than those that occur on other types of particles with different types of organic carbon or other factors that tend to control the release of constituents from the sediment particles to the organism, either through release to the interstitial waters and exchange with the overlying waters or through bio-uptake by benthic and epibenthic organisms.
Water Quality Criteria for
Protection Against Excessive Bioaccumulation
The US EPA's approach toward developing water quality criteria for chemicals that tend to bioaccumulate typically utilizes a bioaccumulation factor that represents a worst-case situation that was observed at the time the criteria were developed. For example, for PCBs, the water quality criterion was based on Lake Superior water situations where a certain concentration of PCBs in the water was found to co-occur with a certain concentration of PCBs in large predator fish, such as lake trout. It has been known for many years, however, that concentrations of PCBs in other waters do not result in the same bioaccumulation of PCBs in similar kinds of fish. The work of Dr. Lee's graduate students and Dr. Lee in the 1970s demonstrated this situation with respect to the bioaccumulation of PCBs in fish in the New York Harbor/Bight area. The American Fisheries Society's PCB subcommittee (Veith et al., 1979) in their review of the US EPA "Red Book" criteria of 1976 cautioned against assuming that a bioaccumulation factor that was developed for PCBs in Lake Superior would be applicable to other waterbodies. With few exceptions, the actual amount of bioaccumulation that occurs for a given concentration of a chemical in water and/or sediments is highly site-specific and cannot be extrapolated to other situations. This makes the US EPA's bioaccumulation-based water quality criteria highly over-protective in most situations.
Based on the discussions at the US EPA's National Sediment Bioaccumulation Conference, the only reliable approach today for determining whether there is excessive bioaccumulation in a particular type of organism that is present in a particular waterbody during a certain time of the year is to actually measure the tissue residues in that organism. All other approaches, such as BAF, BASF, biokinetic models and laboratory-based bioaccumulation test results, that are being used to estimate potential bioaccumulation in higher trophic-level organisms are unreliable.
The basic problem with the various approaches that are being used to estimate bioaccumulation is that none of them properly incorporates the aquatic chemistry and transport fate information in estimating tissue residues in an aquatic organism based on either sediment and/or water concentrations of the chemical of concern.
Factors Influencing Bioaccumulation
Generally, it is found that for the chlorinated hydrocarbon pesticides and other highly hydrophobic chemicals that tend to bioaccumulate, greater bioaccumulation occurs in organisms with higher fat content. Any bioaccumulation measurements should also include measurement of fat content. Care must be exercised, however, to reliably determine fat content since there are problems with some of the procedures that are being used.
It should not be assumed that the areas with the highest concentrations of the chemical in water and/or sediments is the area from which the chemical leading to excessive bioaccumulation is derived. Aquatic life toxicity due to chemical constituents in water and sediments bioaccumulation is a function of available forms of constituents. Available forms cannot be predicted based on chemical concentrations. Such predictions must consider the mechanism of binding of the constituents in the sediments. This binding, in turn, determines the amount of constituents that is in equilibrium with interstitial (pore) water.
There is substantial evidence that for some chemicals the concentrations of binding materials, such as TOC for some organics and sulfides and iron hydroxide for metals, tend to reduce the availability of chemical constituents for bioaccumulation in aquatic organisms within the sediments and in the waterbody in which the sediments are located. It is also becoming more evident that total organic carbon normalization of sediment concentrations of potentially hazardous chemicals as is proposed to be used in the US EPA's proposed sediment quality criteria is not a constant value. The TOC toxics/bioaccumulatable chemical coupling is not a single factor, but can vary by a factor of 10 or more.
Relating Bioaccumulatable Chemical Concentration
to Organism Toxicity-Ecological Effects
Over the past 30 years, there have been numerous attempts to try to relate tissue residues (organism body burden) to toxicological impacts on the organisms that have accumulated the residue. While considerable data exist on the amount of heavy metal or organics bioaccumulated in organism tissue that were found in organisms that have experienced toxicity due to the same chemical, there is limited ability today to relate organism toxicity to bioaccumulated residues (body burdens). At this time, there is no reliable relationship between accumulated residues and toxicities. This is the result of the fact that accumulated residues are typically in non-target organ areas, such as fish muscle. The toxicity, however, would be specifically directed to a particular organ, such as through the gills, where the toxicity may not result in an accumulated residue.
A variety of other approaches are being used to try to estimate the excessive concentrations of chemicals in fish and other aquatic organism tissue that are harmful to the organism that has accumulated the residue or to higher trophic-level organisms. These range from so-called "NAS" criteria to various approaches that involve a comparison of the concentration in an organism tissue to some background (reference) concentration for organisms taken from another location. The California Water Resources Control Board staff made a significant error several years ago in interpretation of the reliability of the so-called NAS (National Academy of Sciences) tissue residue values. These values are not reliable values as used by the Board and regional boards. They are not recognized by the National Academy of Sciences as appropriate values for such use. The US EPA does not recognize them as valid values.
The senior author (Dr. Lee) was involved with the National Academies of Science and Engineering in the early 1970s as an invited peer reviewer of the "Blue Book of Water Quality Criteria" from which these values were derived. He has discussed this issue with Carlos Fetterolf, former Director of Aquatic Biology in the Department of Natural Resources for the state of Michigan and the coordinator for the "Blue Book" development, who was shocked that anyone was using these values as reliable values today for judging excessive bioaccumulation of chemicals in aquatic life.
It is important to recognize that elevated concentrations of a chemical in aquatic organism tissue cannot and should not be interpreted to mean that the organism that has accumulated the residue or higher trophic-level organisms are being adversely impacted by the elevated concentrations. Many organism tissues, including man, accumulate residues of chemicals without apparent harm. There are, however, for some chemicals, concentrations of accumulated residues that represent significant threats to the use of these organisms as food by higher trophic-level organisms.
About all that can be said reliably at this time is that accumulated residues in an aquatic organism demonstrate an exposure of the organism to available forms of a constituent of concern. They cannot be used to reliably assess adverse impacts on the organism. The significance of an accumulated residue must be judged based on its threat to higher trophic-level organisms.
Human Health Effects
The primary focus of concern with respect to bioaccumulation of hazardous chemicals must be on those chemicals that bioaccumulate to a sufficient extent in animal organism tissue to cause the organism to be considered hazardous to those who use the organism as a source of food. While in the past, Food and Drug Administration (FDA) Action Levels were used to judge excessive bioaccumulation, there is increasing agreement today that the focus of assessing what constitutes excessive bioaccumulation should be based on the US EPA's risk assessment approach in which the hazard of the chemical is evaluated based on its potential to cause cancer or, for non-carcinogens, toxicity in humans. This approach considers the cancer slope factor, the average amount of fish or other organisms consumed per day and the concentration of the hazardous chemical in the ingested food. It is becoming widely recognized that the US EPA's "Gold Book" fish consumption rates of 6.5 grams per day are low compared to the actual consumption that occurs by some populations (those whose diet is primarily fish from a local waterbody).
The FDA Action Levels are considered by many as too high an allowable concentration in an aquatic organism edible tissue of a potentially hazardous chemical. The differences between FDA and risk-based approach estimates of allowable edible organism tissue residues is thought to be due to the fact that the FDA incorporates economic and other factors into establishing an Action Level. It is important to point out, however, that there are, especially for mercury, significant differences between US EPA and FDA interpretation of the information that is available on the hazards of mercury to humans. It is the FDA's position that the US EPA is significantly over-estimating the hazard of mercury to humans in establishing their risk-based allowable tissue residues.
While the US EPA developed some wildlife-based bioaccumulation criteria as part of the Great Lakes Initiative, these criteria have limited reliability in predicting the bioaccumulation that will occur in other waterbodies for the same higher trophic-level organism as well as for other types of higher trophic-level organisms. It will likely be decades before reliable water quality criteria can be developed that can be used to regulate bioaccumulatable chemicals for the protection of wildlife. For now, it will have to be assumed that wildlife will be protected to some degree by human health-based criteria. Normally, except for those who utilize local fisheries as their primary source of food, this approach underestimates the hazard that chemicals represent to wildlife since some forms of wildlife will tend to utilize fish and other aquatic organisms as their primary source of food and thereby receive a higher exposure to hazardous chemicals that have bioaccumulated in the fish.
Deficiencies in Current US EPA Regulatory Programs
for Bioaccumulatable Chemicals
Currently, the US EPA and other regulatory agencies are persisting with a highly inappropriate, technically invalid, regulatory approach of basing the assessment of the excessive concentrations of chemical constituents in water and/or sediments on a national bioaccumulation factor for a particular chemical that is applicable to all waters within the US. The Agency is using a convoluted approach for establishing water quality criteria for bioaccumulatable chemicals in which a bioaccumulation factor is developed based on an observed water concentration tissue concentration relationship that is developed for a particular organism in a particular waterbody. The bioaccumulation that has occurred is then developed into a BAF that is then used to develop a water quality criterion designed to keep the tissue residue in the organism below some critical level. In the past, the FDA Action Levels were used; today, there is increasing use being made of risk-based concentrations in aquatic organism tissue that consider the hazard associated with the use of the organism as human food. It has been recognized for over 20 years that this approach is technically invalid. There were several papers presented at the US EPA National Sediment Bioaccumulation Conference which demonstrated that what was known 20 years ago in this area is applicable today.
The US EPA and others are following similar approaches for regulating chemical constituents in sediments. While there are no proposed national sediment criteria for bioaccumulatable chemicals, site-specific criteria are being developed as part of sediment remediation programs. Great caution must be exercised in the use of site-specific BAFs and BSAFs in predicting the impact of sediment remediation programs on the concentrations of hazardous chemicals that will occur in higher trophic-level organism tissue. Such extrapolations may prove to be highly unreliable.
At this time, only a small number of the potentially hazardous chemicals that tend to bioaccumulate in aquatic organism tissue are being regulated by the US EPA and other agencies. The basic problem is that there are about 75,000 chemicals in use in the US today. Only a few of these have been examined for their potential to bioaccumulate to excessive concentrations in aquatic organism tissue. It has been known since the early 1960's that gas chromatograms of extracts of aquatic organism tissue often show a large number of unidentified peaks of chemicals that are accumulating in fish tissue. Since the 1980's with the development of GCMS, it is possible to identify many of these chemicals. However, little regulatory attention is being given to determining what chemicals are bioaccumulating in fish tissue and the public health significance of this bioaccumulation. This problem arises out of the significant error that was made in the mid-1970s in formulating the Priority Pollutant list and the use of this list as the basis for regulating hazardous chemicals in the environment. There is an urgent need to significantly broaden the scope of the nation's water pollution control programs to more appropriately determine what chemicals are bioaccumulating in aquatic organism tissue, the potential public health and environmental significance of such bioaccumulation and, where significant, develop control programs for those chemicals which are not now regulated as bioaccumulatable chemicals.
Any study of bioaccumulation that is occurring in aquatic organisms of a region should examine the organisms for more than just the Priority Pollutants. If chemicals are found in aquatic organism tissue extracts by GC or GCMS, the presence of the unidentified as well as identified chemicals should be reported with the characteristics of the chemical identified to the extent possible. Such reporting could eventually lead to more appropriate focusing of resources on developing technically valid, cost-effective approaches for regulating hazardous chemicals that bioaccumulate in aquatic organism tissue.
Bioaccumulation of Mercury
Recently, Dr. Lee has given considerable attention to the mercury situation on what is known about mercury chemistry relative to being able to predict based on mercury concentrations in water and/or sediments whether excessive bioaccumulation of mercury will occur in higher trophic-level aquatic organisms. It is concluded that there is essentially no predictive capability for relating concentrations of mercury in water and/or sediments to the concentrations in fish or other higher trophic-level organisms. This is of particular importance in the Sacramento River watershed as well as a number of other waterbodies since there are several locations where mercury residues are contributing to elevated mercury concentrations in the Sacramento River watershed waters. It should be understood that there is an urgent need to better define how and to what extent mercury from a particular source area, such as Cache Creek, etc., contributes excessive mercury in a Sacramento River watershed waterbody or downstream thereof. The situation could develop where large amounts of public funds are spent trying to control mercury in mine tailings or some other source so that it does not enter the Cache Creek system only to find that the mercury in this creek is of little or no consequence in the Sacramento River system and downstream, such as San Francisco Bay, in leading to excessive bioaccumulation.
Bioaccumulation Studies in the Sacramento River Watershed
Toxics Control Program
With respect to the Sacramento River Watershed Toxics Control monitoring Program, the focus should be on determining whether excessive bioaccumulation of the commonly found chemicals that cause bioaccumulation problems (health advisories) is occurring. This means that a substantial amount of funds should be made available early in the program to conduct a survey similar to the ambient water toxicity testing survey to define where in the Sacramento River watershed there are excessive concentrations of chlorinated hydrocarbon pesticides, PCBs, dioxins and mercury. The first phase of this program should be to develop a comprehensive review of the current Water Resources Control Board's Toxics Substances Monitoring Program data. This review would help define areas where there have been problems in the past as well as to find areas where there is need for further study to either determine whether excessive accumulation of these chemicals has occurred and/or is continuing to occur in a particular area.
A set of abstracts prepared by several of the presenters at the US EPA National Sediment Bioaccumulation Conference was made available to the conference attendees. The proceedings of the conference are expected to be available early next spring.
Lee, G.F. and Jones, R.A., "Water Quality Aspects of Dredging and Dredged Sediment Disposal," In: Handbook of Dredging Engineering, McGraw Hill pp. 9-23 to 9-59, (1992).
Lee, G.F. and Jones-Lee, A., "Contaminated Dredged Sediment Disposal Criteria," Proc. ASCE "Dredged 94" Second International Conference on Dredging and Dredged Materials Placement, Orlando, FL, pp. 121-130 (1994).
Veith, G.D. (coordinator), Carver, T.C., Jr., Fetterolf, C.M., Lee, G.F., Swanson, D.L., Willford, W.A., and Zeeman, M.G., "Polychlorinated Biphenyls," IN: A Review of the EPA Red Book: Quality Criteria for Water, American Fisheries Society, Bethesda, MD, pp 239-246 (1979).
Additional Information on Cache Creek Mercury G. Fred Lee & Associates
27298 E. El Macero Dr.
El Macero, California 95618-1005
Tel. (530) 753-9630 • Fax (530) 753-9956
web site: http://members.aol.com/gfredlee/gfl.htm
Please note the new area code for telephone and fax has been changed to 530
Additional Information on Cache Creek Mercury
G. Fred Lee & Associates
April 29, 1998
CALFED Bay-Delta Program
Water Quality Technical Group
1416 Ninth Street; Ste 1155
Sacramento, CA 95814
A couple of months ago you asked me to review a draft statement developed by Gail.Louis of the US EPA Region 9 on a mercury control strategy for the Delta. I wish to follow up my comments on that draft statement with some additional comments. These additional comments arise from my attending a Cache Creek watershed stakeholders meeting on March 9, 1998 where the program was devoted to Cache Creek mercury issues. This situation provided an opportunity to hear various "experts" and the public discuss their views on these issues.
Significance of Cache Creek as a Source of Mercury for the Delta
Based on the work of Chris Foe and others, there is no question that Cache Creek represents one of the most important sources of total mercury for the Yolo Bypass and the Delta, including the northern part of San Francisco Bay. The total annual loads that are carried by high winter stormwater runoff flows of total mercury derived from Cache Creek appear to be about the same as that derived from the rest of the Sacramento River watershed. With respect to understanding the sources of mercury for Cache Creek, the work of several groups is beginning to narrow in on some of the more important sources of total mercury. Within a few years and possibly with additional support, it should be possible to better understand the specific sources of mercury within the Cache Creek watershed that significantly contribute to the total mercury that is carried into the Delta each year. There is general agreement that this is a high-priority area for activity. From the information available, it appears that while there is general mercury contamination throughout much of the upper Cache Creek watershed in the former mining areas, only a few of the potential sources appear to be controlling the high concentrations of mercury that are associated with high stormwater flows each winter.
Water Quality Impacts of Mercury
Fish and other aquatic life throughout most of the Cache Creek watershed contain excessive mercury based on US EPA Region 9 guidance of one meal per week. In some areas, the edible fish contain excessive mercury based on US EPA and FDA guidance/action levels for one meal per month. Some fish in San Francisco Bay have been found to exceed both the one meal per week and many fish exceed the one meal per month mercury guidance value. It has recently been found that the Sacramento River system from Shasta through past Sacramento have white catfish with mercury above the one meal per week guidance value. Trout taken from these waters are not bioaccumulating excessive mercury based on the one meal per week value. At this time, the current mercury concentrations in Delta fish are unknown but are suspected to be above guideline values. I understand that a program that is funded by CALFED that is being conducted by the DeltaKeeper and the Regional Board is addressing this issue
One of the issues that needs to be resolved in the near future is the actual consumption rate of fish from various areas of Cache Creek as well as the Delta. Bill Jennings, of the DeltaKeeper, has indicated that there are some Asian heritage populations that are consuming fish from the Delta at more than one meal per week. If this is the case, then this could significantly decrease the allowed fish tissue mercury levels from the 0.14 mg/Kg value currently recommended by the US EPA Region 9 for the one meal per week consumption rate.
It is also possible, although there is no direct evidence for this at this time, that higher trophic level organisms, such as mammals and fish-eating birds, i.e. eagles, may be adversely impacted by the elevated mercury content of fish and insects in Cache Creek.
There is general agreement among the "experts" that the issue I have raised several times with the CALFED Water Quality Technical Group management of focusing on bioavailable mercury in the mercury control program for the Delta is the approach that must be followed if CALFED funds are to be used wisely. It does not appear that the approach that the CALFED Water Quality Technical Group has adopted of setting the US EPA water quality criteria/state standards as the target value for mercury control is an appropriate approach to be followed for mercury and, as will be demonstrated eventually, for many other constituents.
With respect to mercury, there is considerable evidence that mercury in various forms has significantly different bioavailability. For example, because of its very low solubility, the mercury ore cinnabar which is a mercury sulfide mineral, is considered to be non-bioavailable or at least its bioavailability is low. Chris Foe has recently informed me that he is aware of a study that showed that mercury in cinnebar is bioavailable. The issue that must be addressed however is whether the cinnebar which is likely to be the primary mineral in the high Cache Creek winterflow mercury is converted to methylmercury at a sufficient rate within the Delta and northern San Francisco Bay to significantly contribute to the excessive mercury concentration in Delta and Bay fish. It is possible that laboratory studies on cinnebar could show that while it is bioavailable, the rate of conversion to methylmercury is sufficiently slow under ambient water conditions to be of minor importance in contributing to the excessive mercury bioaccumulation problems.
At the March 9th meeting, I found that some of the statements made about bioavailable mercury are not based on a proper assessment of this situation. Through discussions with some of those making these statements, I learned that they are basing their bioavailable mercury statements with respect to various mercury species on the ingestion by mammals. It has been known for well over 30 years that bioavailability through stomach-intestinal track uptake in mammals can be significantly different than bioavailability in the environment for such things as methylation to convert to methylmercury which, in turn, bioaccumulates in fish tissue. It is also clear that mercury that accumulates in fish and other aquatic life is not necessarily only methyl mercury. While it is often the dominant form, there is evidence that other forms of mercury are becoming associated with organisms.
One of the key areas of concern is the potential for cinnabar ores which occur in large amounts near former mercury smelting areas as waste piles/tailings to contribute mercury in bioavailable forms. I have discussed this issue in my past writings where I have mentioned the need to specifically address this issue, not only with respect to what happens in Cache Creek, but from a CALFED perspective, what happens in the Delta and in the upper reaches of San Francisco Bay. Carefully designed and implemented studies need to be carried out in the near future to determine which of the high winter flow forms of mercury that are carried by Cache Creek are, in fact, bioavailable in the various environments that exist in the Delta and Upper Bay.
While there are some who claim they can use certain chemical procedures to make estimates of bioavailable forms, great caution must be exercised in accepting these claims as reliable. Often, the mercury that accumulates in various areas is a mixture of forms and while the dominant form might be a non-bioavailable form, there may be enough other forms which would be considered minor based on chemical testing procedures, to lead to excessive bioaccumulation. It is my recommendation that a combination of specific chemical measurements including methylmercury as well as some of the techniques developed by Darell Slotton of actually measuring mercury that accumulates in benthic organism be used to assess bioavailability.
Shallow Water Habitat
There is considerable concern among the experts about CALFED and others developing shallow water habitat where the area could be exposed to Cache Creek high mercury flows. Shallow water habitats(wetlands) are well-known to promote methylmercury formation. By actively pursuing shallow water habitat development, CALFED could be creating massive problems of excessive bioaccumulation in fish and other aquatic life that develop in these areas. I appreciate that CALFED support of shallow water habitat mercury bioaccumulation work is being conducted. I recommend that this work be critically reviewed by an independent panel to be sure that it covers all of the areas that need to be covered to protect CALFED's/the public's interests.
In addition to reviewing the issue of shallow water habitat developing methylmercury that bioaccumulates to excessive levels within fish and other aquatic life, by a critical review of the current on-going studies on mercury, it would be possible to identify significant information gaps that need to be filled in the mercury information base that is needed to formulate a technically valid, cost-effective control program to begin to manage the mercury problem in Cache Creek, the Delta and upper San Francisco Bay. The Cache Creek mercury meeting has provided additional support for many of the issues that I raised previously on the approach that CALFED needs to consider to begin to formulate a mercury management program for Delta fish. A particular importance is the need to develop a CALFED mercury technical leader who would be assisted by an advisory panel that would advise CALFED management on how best to proceed to develop and then implement a technically valid and cost-effective mercury control strategy for the Delta.
I have previously mentioned that the US EPA has developed a set of documents devoted to a national review of the environmental mercury problem. I have recently received notice that the agency released "Mercury Study Report to Congress. Volume 7. Characterization of Human Health and Wildlife Risks from Mercury Exposure in the United States. 166P" (NTIS order number: PB98-124795LEU). This volume is primarily devoted to characterization of the risk for mercury emitted to the environment from various anthropogenic sources. The volume describes human and wildlife effects of mercury exposure including analysis of uncertainty in quantitative risk estimates. The agency has also released "Mercury Study Report to Congress. Volume8. An Evaluation of Mercury Control Technologies and Costs." (NTIS order number: PB98-124803LEU).
The US EPA has also recently released the Second Edition of "Guidance for Assessing Chemical Contaminant Data For Use in Fish Advisories Volume II: Risk Assessment and Fish Consumption Limits (EPA 823-B-97-009)". This volume is available from the US EPA, National Center For Environmental Publications and Information, 11029 Kenwood Rd., Cincinnati, Ohio, 45242, or calling 513-489-8190.
If there are questions about these comments, please contact me.
G. Fred Lee, PhD, DEE
Copy to: R. Woodard
G. Fred Lee & Associates
27298 E. El Macero Dr.
El Macero, California 95618-1005
Tel. (530) 753-9630 • Fax (530) 753-9956
Please note the new area code for telephone and fax has been changed to 530
G. Fred Lee & Associates
April 29, 1998
CALFED Bay-Delta Program
Water Quality Technical Group
1416 Ninth Street; Suite 1148
Sacramento, CA 95814
Following up on your request to review the report by Gail Louis of US EPA Region 9 devoted to "Mercury Action Example," I wish to provide the following comments.
Ms. Louis states,
"This action is intended to provide an example of how we believe the action strategies comprising CALFED's Water Quality Common Program could be fleshed out in greater detail to provide the reader with both a better context within which to consider the action (including a problem statement and discussion of existing programs) and greater specificity regarding the intended action strategy itself."
It is stated that this "mercury action" represents work in progress.
As background to these comments, I have been involved in water quality evaluation and management from an aquatic chemistry, public health and aquatic toxicology perspective for over 35 years. My work has included 30 years of university graduate-level teaching and research during which I had about 100 graduate students do their master's theses or Phd dissertations on the aqueous environmental chemistry of a constituent relative to developing technically valid, cost-effective control programs for the constituents in aquatic systems. Mercury has been one the constituents that I have worked on periodically over this period. One of the issues of particular concern to me is the potential significance of various forms of mercury as a source of mercury that leads to excessive bioaccumulation. Over the last half a dozen years, I have become interested in the excessive mercury bioaccumulation issues in the Sacramento - San Joaquin River Delta and San Francisco Bay. Upon learning of Chris Foe's work on Cache Creek, I have become increasingly involved with Chris, Bill Croyle and others who are concerned with the Cache Creek mercury problem. I have attended a number of meetings organized by the Central Valley Regional Water Quality Control Board staff devoted to these issues. Further, I am an active participant in the Cache Creek mercury work group.
Last summer I submitted a proposal to CALFED for support that would have enabled me to provide my expertise and experience to develop coordinated technical guidance on how to develop the technical aspects of regulating the mercury associated with Cache Creek high flows. While the Cache Creek mercury group supported the activities that I proposed to conduct on behalf of the group through CALFED, the CALFED review process did not enable this proposal to be sufficiently ranked to make it through the first level of review. This is not surprising since it was mechanically reviewed as though it were a research proposal rather than a proposal to provide me with sufficient funds to serve as a facilitator to help CALFED, the Cache Creek Mercury Group and all stakeholders to develop a technically valid, cost-effective approach for managing the excessive bioaccumulation of mercury that occurs within the Delta and upper San Francisco Bay. A key component of the proposal was funding to provide independent peer review of the various research projects and CALFED activities on mercury control. This peer review was singled out as by the Cache Creek Mercury Group as a high priority for activities.
A copy of that proposal is appended to these comments since it summarizes key information on the mercury problem that I have found needs to be considered in formulating the CALFED mercury management program.
Page 1, second paragraph, states that high levels of mercury in fish and recreational fish have rendered certain fish inedible. More appropriate terminology would be that the consumption of certain fish is a risk to public health, especially pregnant women. The fish are edible; the mercury in them is a risk to the health of those who consume them.
Page 1, third paragraph, makes reference to the 1973 National Academy of Sciences guidelines to protect aquatic resources and their predators as a source of reliable information on excessive mercury accumulation in fish tissue. I was an invited peer reviewer for the National Academy of Sciences/National Academy of Engineering "Blue Book of Water Quality Criteria" (1972) which is the document which contains the values referred to in this paragraph. It has been found that the state of California Water Resources Control Board staff and only this staff have given far greater credence to the NAS/NAE "Blue Book" values developed in the early 1970s as providing reliable information on excessive concentrations of constituents in aquatic organism tissue as it may impact the organism or higher trophic level organisms. The so-called NAS values are not credible values for determining excessive concentrations of mercury or, for that matter, any other constituent in fish tissue.
Because of the persistence of the State Board and regional board staffs in continuing to use these values, I contacted Carlos Fetterlof who directed the "Blue Book" effort for the National Academies and who is also former chief biologist for the state of Michigan pollution control agency and served as the executive director for the Great Lakes Fisheries Commission for many years concerning his view on the appropriateness of the state of California using the so-called NAS values as a basis for judging excessive concentrations of constituents in fish tissue. Mr. Fetterlof confirmed my finding that the 1973 "Blue Book" values are not being appropriately used by the state of California. It should also be noted that the US EPA, the National Academies of Science, or no other state use the National Academy 1973 "Blue Book" values as credible values. They are not recognized by the National Academy bioaccumulation group as credible values for bioaccumulation in fish. In fact, when I contacted the director of that group a couple of years ago, he indicated that he had never heard of the NAS values for excessive concentrations of chemical constituents in fish tissue. The US EPA Region 9, the State Water Resources Control Board and the regional boards should immediately terminate any reference to the NAS values as having any credibility for determining excessive concentrations of any constituent in fish tissue as they may affect higher trophic level organisms.
Page 1, fourth paragraph, indicates that the State Water Resources Control Board has listed Delta waterways as use impaired because of excessive concentrations of mercury. It is my understanding that that information is significantly dated and may not be appropriate today. There are no recent concentration data on mercury content of fish tissue within the Delta. While it is believed that the excessive concentration still exists, this needs to be confirmed through appropriately conducted studies. It is my understanding that funds have been made available through CALFED for this purpose.
Page 1, last paragraph, states, "In general, large-scale, systematic sampling of a variety of fish species have not been conducted in the Bay." The studies that were conducted as part of the BPTCP by the San Francisco Regional Water Quality Control Board represented a fairly comprehensive study of excessive bioaccumulation of hazardous chemicals, including mercury, within fish in the Bay. Further, this past summer additional sampling of this type was again conducted. When these data become available, there will be two fairly comprehensive studies conducted several years apart which provide data on the mercury content of fish within San Francisco Bay. The statement on the bottom of page 1 about the studies not being conducted is not in accord with what has been done.
On page 2, end of first paragraph, mention should be made about finding excessive mercury in fish taken from Putah Creek near where the University of California, Davis campus wastewaters are discharged to the Creek. Further, the UCD work referenced in the first paragraph of page 2 includes work on Cache Creek organisms. This should be mentioned.
Page 2, third paragraph, next-to-last line, uses the term "transvection." I do not understand that term. I taught aquatic chemistry for 30 years to graduate-level environmental engineering and environmental science students. I have never heard the term "transvection." This problem likely exists for many others who may read this review. It should be explained.
Page 3, first full paragraph, states, "More importantly, these sediments contain mercury in its most reactive forms." I would be interested in seeing the technical back-up for such a statement.
Page 3, second full paragraph, places considerable emphasis on the mercury associated with hydraulic mining activities. While this may be justified, certainly of greater importance today in terms of CALFED program development is the input of mercury from Cache Creek. As discussed in my CALFED proposal of last summer, there is an urgent need to determine whether the mercury associated with high flow is in Cache Creek that enters the Yolo Bypass, the Delta and upper San Francisco Bay significantly contribute to excessive bioaccumulation of mercury. The focus of these studies must be on determining whether the expenditure of funds for controlling mercury input to Cache Creek will change the excessive bioaccumulation of mercury problem that exists in Delta and San Francisco Bay fish. There may be such a massive natural as well as anthropogenic mercury reservoir in the Delta and Bay that spending many tens to hundreds of millions of dollars controlling mercury inputs to the Bay will have no impact on the excessive bioaccumulation of mercury within Delta and Bay fish.
One of the primary issues that needs to be addressed is what specific forms of mercury contributed from Cache Creek lead to excessive bioaccumulation within the Bay and Delta.
Page 4, third paragraph, is extremely important but may be misleading where it states,
"Determining the relative contributions of the various sources (mercury mines, hydraulic mining debris, recycling from depositional areas) to the primary problem (methyl mercury in fish) is necessary to developing cost-effective solutions to the system's mercury problems."
There is need to understand the relative contributions of mercury from various sources. This understanding, however, must be based on mercury that is either in or can be converted to within the Delta and the Bay bioavailable mercury. The total mercury loads from various sources is not the issue that needs to be addressed. It is the mercury that contributes to the excessive bioaccumulation within the Delta and Bay that must be addressed to develop technically valid, cost-effective programs for controlling the mercury problems within the Delta and Bay.
Page 5, third paragraph, states,
"UC Davis research - Davis Creek reservoir, Marsh Creek watershed, bioavailability
Researchers from UC Davis have determined that fish tissue concentrations can be predicted from lower trophic level invertebrate concentrations."
From my understanding of the data that exist, this statement is an inaccurate representation. While concentrations of mercury accumulate in insects, insect larvae and other benthic invertebrates, to my knowledge there is not a clear, well-defined relationship between the concentrations in benthic invertebrates and fish.
Page 5, fifth paragraph, states, "In December 1997, some CALFED Category 3 restoration funds were directed toward evaluating the effects of wetland restoration on methyl mercury production in the estuary." It further states, "This three-year study will quantify changes in methyl mercury production caused by restoration activities and evaluate the availability and impact of mercury of the Bay-Delta ecosystem." That statement is not an accurate representation of what can be accomplished with these studies. First, under no circumstances will these studies evaluate the impact of mercury on the Bay-Delta ecosystem. These studies may provide some inference on some limited aspects of this issue. It is questionable, however, that they will even begin to address in a reliable way impacts on ecosystems. They may address, if properly implemented and reported, the transfer of mercury in sediments as part of the restoration area to benthic invertebrates and possibly to fish. It also should be understood that what might be accomplished in a three-year study of these types of issues may have limited applicability to longer term mercury transformations that will occur in CALFED shallow water habitat development projects. A three-year period is too short a period to follow the transformations that will occur in developing a wetlands-type habitat.
Page 5 presents an Action Plan/Strategy. The first item is to establish a Task Force to facilitate information exchange in development of a regional mercury strategy. This is an appropriate activity. The funds that I have requested from CALFED were specifically directed toward establishing a technical advisory panel (Task Force) of interest to stakeholders and independent peer reviewers. The efforts of the Central Valley Regional Water Quality Control Board staff, specifically Bill Croyle and Chris Foe, have already made significant strides toward establishing a technical advisory panel that could be of assistance to CALFED in formulating its mercury control strategy. There is however, need for support of this panel's activities of the type that are discussed in my proposal to CALFED where someone with a high degree of expertise, experience and demonstrated productivity would provide technical leadership and guidance in formulating and implementing the technical advisory panel (Task Force) activities.
Item 2 focuses on source identification and assessment studies. Source identification should focus on those forms that are converted within the Delta and Bay to methyl mercury that bioaccumulates in fish tissue. This item should be combined with item 3, directed research to better understand mercury cycling in the Central Valley and estuary.
Item 4, carrying out pilot mercury control programs and evaluating their effectiveness must focus on bioavailable forms of mercury and not necessarily total mercury. The key component of my proposal which must be one of the first phases in developing a technically valid, cost-effective control program for the Cache Creek mercury inputs is the determination of whether the additional mercury added to the Delta and Bay each year during high flow periods significantly contributes to the current bioaccumulation problem. More appropriately, would the expenditure of many millions of dollars to control this mercury input significantly change the excessive bioaccumulation of mercury in fish tissue within the Delta and Bay?
The second bulleted item on the bottom of page 5, mentions various types of studies. Inadequate attention is given in these studies to bioavailable mercury loads. This must be based on a proper assessment of how and to the extent a mercury load from a particular source when present in the Delta and Bay converts to methyl mercury. These issues appear to be covered to some extent by the first bulleted item on page 6.
The other action items listed are appropriate as far as they go. The key issue, though, will be finding an individual with high degrees of expertise and experience with mercury and water quality issues that can devote substantial time to helping CALFED and the stakeholders develop and implement a technically valid, cost-effective mercury control program who will provide technical guidance and conduct the activities needed to formulate a draft CALFED a mercury control strategy. When this strategy has been approved by stakeholders, the individual response would help CALFED and others implement it.
I have recently been in contact with colleagues who are involved in the Florida Everglades' mercury problem. This is also a large, multi-faceted program. This program is being hampered by a lack of strong technical leadership. The same kinds of problems could develop in the CALFED program, unless such leadership is provided. It is doubtful that the leadership will be developed without specific CALFED funding.
It is important to understand that my comments on the need for leadership are not based on an attempt to gain support for my activities. As indicated in the proposal, the work that I offered to do for CALFED in this area was going to be done at a significantly reduced consulting rate compared to my normal rates. I indicated that I would donate substantial consulting time to this issue if CALFED would provide the requested support. At this time, that offer still stands although since then I have acquired substantial research support for work in other parts of California on non-Delta related issues which will encumber much of the time that I have for donated services on behalf of CALFED or other groups.
If you have questions about these comments, please contact me. Please let me know if I can be of further assistance.
G. Fred Lee, PhD, DEE
Copy to: W. Croyle, C. Foe, R. Woodard, G. Louis
Executive Summary Development of a CALFED Management Approach for Controlling
Excessive Mercury Bioaccumulation in Delta/Bay Fish
Development of a CALFED Management Approach for Controlling
G. Fred Lee, PhD, DEE
G. Fred Lee & Associates
The Problem- The excessive bioaccumulation of mercury in edible fish tissue is one of the most significant causes of water quality use impairment in the Delta and San Francisco Bay. Many of the edible fish taken from these waters contain mercury concentrations that are considered to be a health threat to those who consume the fish. Mercury has been selected as one of the primary constituents of concern by the CALFED Bay/Delta program.
Some parts of the Delta watershed, such as the Cache Creek watershed, contain geological formations that have in the past and, to a lesser extent, today provided economic mineral resources that have been mined for mercury and other elements such as gold where mercury was used for gold recovery. These mining activities have resulted in pollution of areas with mine tailings and processed ore residues which contain concentrations of total mercury that could potentially cause excessive bioaccumulation within aquatic life tissue in the area where the mercury residues are found and downstream. The CVRWQCB staff have found that large amounts of mercury are transported to the Delta in the high winter/spring stormwater runoff flows in tributary waters to the Delta. Of particular importance is the Cache Creek watershed which has been identified as one of the dominant sources of total mercury for the Delta.
It has been known for many years that chemical constituents such as mercury exist in aquatic systems in a variety of chemical forms, only some of which are toxic/bioaccumulatable. For mercury, it is well understood that there is little relationship between the total mercury content in a water or a waterbody's sediments and the total concentration of mercury that bioaccumulates in fish tissue. Total mercury content in Delta or Bay waters as well as total mercury fluxes to the Delta and/or Bay is an unreliable predictor of water quality problems associated with mercury. Unless correctly formulated, CALFED could develop a mercury management program that would spend large amounts of funds in mercury input control that has little or no impact on the excessive mercury bioaccumulation problem that occurs within the Delta and Bay as well as some of the Delta tributaries. It is essential that CALFED's mercury control program be based on incorporation of appropriate mid-1990 science and engineering understanding of the potential water quality significance of each of the potential sources of mercury as they impact the excessive bioaccumulation problem within the Delta and Bay fish. Further, there is need to develop an understanding of the potential benefits of controlling mercury input to the Delta and Bay from a particular source or types of sources on the magnitude of reduction of the excessive bioaccumulation of mercury in fish tissue.
In order for CALFED and other agency funds available for mercury control to be used in a technically valid, cost-effective manner, there is need for a highly technical organized effort to determine which of the sources of mercury within the Delta watershed contribute mercury to the Delta and Bay in a form that is present in or converted to mercury forms that can bioaccumulate in Delta and/or Bay fish. In addition, CALFED's mercury management program should be based on sufficient understanding of mercury load to the Delta/Bay - fish bioaccumulation response relationships to enable an evaluation of the cost-effectiveness of implementing mercury control to various degrees from various sources.
The overall objective of this project is to fund a CALFED effort that will enable CALFED to formulate the most technically valid, cost-effective mercury control program that can be developed through near term, site specific investigations of the potential significance of various forms of mercury from various sources as a contributor to the excessive mercury bioaccumulation problem that exists in Delta and Bay fish.
Approach- Dr. G. Fred Lee will serve as a consultant to CALFED management, formulating a mercury control strategy. This strategy will provide the technical basis for CALFED's mercury control program. The funding of this proposal will provide Dr. Lee with the resources necessary to spend additional time on these issues beyond his already voluntary contribution of time and resources to formulation of a mercury control strategy for the Delta and Bay. In addition, the funds in this proposal will allow Dr. Lee to organize in cooperation with CALFED management, regulatory agency representatives, and mercury researchers in the area, a technical advisory panel of national/international environmental mercury experts. This panel will provide independent peer review of the approaches being used to formulate the CALFED mercury control strategy.
Budget -The first year of this three year project has a proposed budget of $70,750.00. $27,000.00 of this amount is devoted to supporting three technical consultants attending two meetings per year. The remainder of the funds is devoted to the support of Dr. Lee's time, serving as an advisor to CALFED as project facilitator.
Qualifications- For a 30 year period, until 1989, Dr. Lee taught graduate environmental engineering and environmental science courses at several major US universities. During this time, he conducted over five million dollars in research devoted to defining the sources, water quality and public health significance, and developing control programs for chemical constituents in aquatic systems. He has published over 650 papers and reports on his work. Since 1989, he has been a full-time consultant to governmental agencies and industry in the US and other countries in water supply water quality, water and waste water treatment, water pollution control including mining wastes and Delta water quality issues, and solid and hazardous waste management.
Monitoring and Coordination -This project will formulate approaches for monitoring the efficacy of CALFED mercury control programs. It will be coordinated with regulatory agencies, mercury researchers, and all other parties interested in managing the excessive mercury bioaccumulation problem that is occurring in the Delta/Bay.
Development of a CALFED Management Approach for Controlling
Excessive Mercury Bioaccumulation in Delta/Bay Fish
G. Fred Lee, PhD, DEE
G. Fred Lee & Associates
27298 El Macero Drive
El Macero, CA 95618
Tel. (530) 753-9630
G. Fred Lee & Associates is a Sole Proprietorship Environmental Consulting Firm
Contact Person: G. Fred Lee
Many other individuals concerned with excessive mercury bioaccumulation
are anticipated to be participants in this project.
RFP Project Group Type: Other Services
The excessive bioaccumulation of mercury in edible fish tissue is one of the most significant causes of water quality use impairment in the Delta and San Francisco Bay. Many of the edible fish taken from these waters contain mercury concentrations that are considered to be a health threat to those who consume the fish. The California Department of Health Services has issued fish consumption health advisories for fish taken from San Francisco Bay because of excessive concentrations of mercury. Because of this situation, mercury has been selected as one of the primary constituents of concern by the CALFED Bay-Delta program. One of the overall objectives of the CALFED program is the management of mercury input to the Delta and through the Delta into the Bay to reduce the concentrations of mercury in edible fish tissue to levels that do not represent a public health risk to those who use the fish as food.
Some parts of the Delta watershed, such as the Cache Creek watershed, contain geological formations that have in the past and, to a lesser extent, today provided economic mineral resources that have been mined for mercury and other elements such as gold where mercury was used in gold recovery. These mining activities have resulted in pollution of areas with mine tailings and processed ore residues which contain concentrations of total mercury that represent a potential threat of causing excessive bioaccumulation within aquatic life tissue, both in the areas where the mercury residues are found and downstream. Further, there are natural hot springs that discharge mercury to tributary waters of the Delta. The Central Valley Water Quality Control Board (CVRWQCB) staff have found that large amounts of mercury are being transported to the Delta each year by the high winter/spring storm water runoff flows of some of the Delta's tributary waters. Of particular importance is the Cache Creek watershed which has been identified as one of the dominant sources of total mercury for the Delta.
It has been known for many years that chemical constituents such as mercury exist in aquatic systems in a variety of chemical forms, only some of which are toxic/bioaccumulatable. For mercury, it is well understood that there is little relationship between the total mercury content in a water or a waterbody's sediments and the total concentration of mercury that bioaccumulates in fish tissue. Total mercury content in Delta or Bay waters as well as total mercury fluxes to the Delta and/or Bay is an unreliable predictor of water quality problems associated with mercury. CALFED, through developing a mercury management program which fails to appropriately incorporate the aqueous environmental chemistry of mercury that leads to excessive bioaccumulation, could spend large amounts of public funds in mercury input control programs that have little or no impact on the excessive mercury bioaccumulation problem that occurs within the Delta and Bay as well as some of the Delta tributaries. It is necessary that CALFED's mercury control program be based on incorporation of appropriate mid-1990 science and an engineering understanding of the potential water quality significance of each of the potential sources of mercury as they impact the excessive bioaccumulation problem within the Delta and Bay fish. Further, and most importantly, there is need to develop an understanding of the potential benefits of controlling mercury input to the Delta and Bay from a particular source or types of sources on the magnitude of reduction of the excessive bioaccumulation of mercury in fish tissue.
Dr. G. Fred Lee will serve as a consultant/assistant/implementor to CALFED management, CVRWQCB, WRCB, and US EPA, university and governmental agencies (USGS Fish and Wildlife Service, etc.), researchers and others as appropriate to help CALFED formulate a mercury control strategy. This strategy will provide the technical basis for CALFED's mercury control program. The funding of this proposal will provide Dr. Lee with the resources necessary to spend additional time on these issues beyond his already voluntary contribution of time and resources to formulation of a mercury control strategy for the Delta and Bay.
In addition, the funds in this proposal will allow Dr. Lee to organize, in cooperation with CALFED management, regulatory agency representatives, and mercury researchers in the area, a technical advisory panel of national/international environmental mercury experts who can provide independent peer review of the approaches being used and formulate the CALFED mercury control strategy as well as the specific research that will be funded through CALFED that serves as the technical basis for obtaining the information needed to implement the CALFED mercury control strategy.
A project technical advisory group will be organized by Dr. G. Fred Lee and CALFED who will work with Dr. Lee on the week-to-week activities of the project. This group will consist of 3 to 5 individuals who are interested and knowledgeable on one or more aspects of the Delta/Bay mercury problem as well as potential sources of mercury for the Delta/Bay. While considerable amounts of the work of this group will be done through e-mail correspondence and conference calls, periodic (likely monthly) meetings of the project advisory group will be held to discuss specific issues more thoroughly than is possible through electronic communication. Over the past year, Dr. Lee has been involved in several groups that operate largely through e-mail/conference calls. This approach has proven highly effective in carrying out group activities at a considerably reduced cost.
The primary area of focus in this project is the Delta and the upper parts of Northern San Francisco Bay where mercury derived from the Delta is expected to accumulate in the Bay. Of particular concern within the Delta and Bay are those areas where mercury added to these waters would accumulate in the sediments and be converted to methyl mercury that accumulates in recreational and other fish to excessive concentrations that cause the use of these fish as food to be considered hazardous to human health.
The second location where the project activities will be focused is in the Cache Creek watershed that contributes mercury to the Delta with its high winter/spring stormwater runoff. As additional work is done in the Sacramento River Watershed Project on mercury sources for the Sacramento river system that contribute potentially significant amounts of mercury to the Delta and as additional potentially significant mercury sources are defined, the source areas for this mercury will become additional areas of focus for the project.
Expected Benefits and Need for Project
The primary benefits from this project will be the development and implementation of a technically valid, cost-effective CALFED mercury management program that will control the mercury inputs to the Delta and Bay that lead to excessive bioaccumulation of mercury in edible fish tissue. This project will provide the technical information base upon which CALFED can formulate its mercury management strategy. The organization of a high level technical expertise advisory activity for the development and implementation in formulating a mercury control program for Delta and Bay inputs that is based on current science and engineering to the maximum extent practicable is essential for CALFED in order to address the control of excessive mercury bioaccumulation.
Proposed Scope of Work
The funds derived from this project will enable Dr. G. Fred Lee to significantly expand his current voluntary technical assistance in formulating technically valid, cost-effective mercury control programs to the Delta and Bay. Since returning to California in 1989, Dr. Lee has been active in Delta and Bay water quality issues. One of the areas of particular concern to him has been the addition of potentially hazardous chemicals to these systems and those chemicals' impacts on aquatic resources. With the discovery through the SFEI Regional Monitoring Program that many of the Bay fish have excessive mercury in their edible tissue compared to current US EPA guidelines and CVRWQCB staffs finding of high mercury inputs to the Delta associated with high winter/spring Cache Creek flows to the Delta, Dr. Lee has devoted time to review the potential significance of the particulate mercury transported during high flow periods as a cause of the excessive mercury that is bioaccumulating in Delta and Bay fish. Dr. Lee's concern in this matter stemmed from his early 1990's work on behalf of the American Dental Association which indicated that certain forms of mercury were not converted to methyl mercury at a high rate or at all and thereby contribute to excessive bioaccumulation of mercury in fish tissue.
After becoming aware of the high mercury loads being transported to the Delta via Cache Creek, Dr. Lee contacted the CVRWQCB indicating the need to better understand the aqueous environmental chemistry of particulate mercury present in the high tributary flow waters with particular reference to whether this mercury was in a bioavailable form or could be converted to such a form within the Delta or Bay. Over the past several years, Dr. Lee has spent time becoming familiar with the literature pertinent to what is known today about the bioavailability of various forms of mercury in various aquatic environments. He has also devoted attention on how to determine whether mercury from a particular source added to a particular water body would likely be a significant factor in causing or contributing to excessive mercury bioaccumulation. He has discussed this situation with many individuals including an ad hoc Cache Creek Mercury Group organized by Chris Foe of the CVRWQCB. There seems to be considerable interest in this area and a general consensus that work on this topic needs to be done before the CVRWQCB/CALFED can formulate its mercury control strategy for controlling mercury input to the Delta.
Dr. Lee has also become familiar with the problem through serving as a reviewer to the Sacramento County Sanitation District's sponsored recently completed mercury studies associated with some of the gold mining areas in the Sierras. He has also become familiar with the excessive bioaccumulation problem associated with fish taken from Putah Creek near the University of California's campus waste water treatment plant discharged to the Creek. Dr. Lee has recently been invited to become an active participant in the Cache Creek Mercury Technical Workgroup. At a recent meeting of this group, there seemed to be considerable interest in, and need for the developing the kind of program that has been formulated as part of this project proposal. Dr. Lee's specific responsibilities in this project will be to serve as an organizer and implementer of a CALFED activity that is designed to provide CALFED with a current assessment with what is known about the issues that need to be addressed in formulating and implementing a CALFED mercury control strategy.
Dr. Lee will be an organizer and synthesizer of technical information for CALFED on technical issues that should be incorporated into the CALFED mercury control strategy. Because of his technical expertise and experience, with CALFED's financial support for this project he will develop draft issue papers pertinent to formulating the CALFED mercury control strategy. A discussion of important technical issues that need to be resolved in the form of issue papers is included in the Appendix. These issue papers will first be reviewed by the project's technical advisory group and then, after redrafting, will be circulated to anyone interested in the current Delta/Bay mercury bioaccumulation problem, and/or its management, for their review and comment.
The first of the issue papers will be a synthesis of what is known about developing technically valid cost-effective mercury control programs for the Delta and the Bay. This issue paper will also discuss the major data gaps that need to be addressed and how they should be addressed by site specific research associated with the conversion of various forms of mercury in water and sediments into bioaccumulatable forms (methyl mercury) that bioaccumulate in fish tissue. The issue paper would develop consensus statements on issues where the strengths and weaknesses of any particular position that is important to formulating a CALFED mercury management strategy is fully discussed. It is Dr. Lee's intent to hold periodic meetings of all interested parties in the development of the CALFED mercury strategy and its implementation.
Since many of the same issues pertinent to developing a mercury control strategy for the Delta/Bay are pertinent to developing a mercury control strategy for mercury bioaccumulation problems in Cache Creek, Dr. Lee will discuss these issues with those participating in the Cache Creek Mercury Technical Workgroup as well as with others. He will offer to make presentations to the Cache Creek Mercury group on various components of the issue papers as they are drafted and will invite comments on redraft and final papers.
It is anticipated that this initial mercury management issue paper will be completed within four to six months. It will serve as a guide to CALFED on how to allocate resources for developing and implementing a mercury control strategy. As new information becomes available from the literature or from site specific studies, some of which will likely be funded by CALFED, Dr. Lee will update his consensus statement on how CALFED should develop and implement a Delta/Bay mercury control strategy. Dr. Lee plans to meet with CALFED water quality management on at least monthly intervals and will provide summary reports on activities for each month.
The other primary activity associated with funding of this proposal will be the development of a national/international panel of consultants who would meet twice a year with CALFED management, Delta/Bay and Cache Creek mercury researchers and other interested parties to review proposed plans and accomplishments in developing a CALFED mercury control strategy. The first meeting of this panel will take place about six months after initiation of the project and after the draft initial guidance paper has been distributed to interested parties and comments have been received. The consulting panel will be requested to review the second draft of the CALFED guidance document associated with the formulation of the CALFED mercury control strategy. It is possible that a second meeting of this panel will take place near the end of this first project to review their accomplishments during the first year and to develop recommendations on the second year's activities .
At a recent Cache Creek Mercury Technical Workgroup, there was consensus about the need for independent peer review of CALFED mercury projects by knowledgeable experts who do not have specific research projects underway that could be interpreted as a conflict of interest between reviews that they may provide on other projects. The national/international technical advisory panel that will be organized by Dr. Lee, CALFED, and the project technical advisory group, will provide the independent review of specific research components of the CALFED mercury strategy as well as the overall strategy.
One of the key components of Dr. Lee's approach towards providing guidance to CALFED on the development of a mercury management strategy will be the formulation of a mathematical model that incorporates what is known about the key source release, transport, and transformations of various forms of mercury from various sources within the Delta's watershed that are transported to the Delta and Bay that lead to excessive bioaccumulation of mercury within Delta and Bay fish. At Dr. Lee's suggestion, a review of one of the potential models that could be used for this purpose will be conducted at the September 5, 1997 Cache Creek Mercury Technical Workgroup meeting. This and other potential models will be reviewed by Dr. Lee and others as appropriate in order to evaluate their representation of what is now known about mercury transport and transformations.
It has been Dr. Lee's experience, having been involved in modelings of this type since the 1960's, that such models have limited predictive capability and rarely can be used to predict with reliability the impact of altering a contaminant's load to a waterbody on the impact of the constituent on the beneficial uses of the waterbody. Such modeling efforts, however, can be important in systematically organizing the understanding of processes of potential concern, and thereby guide the development of studies to provide the information needed to formulate a management strategy.
By the end of the first year, as a result of funding this project, CALFED will have available a fairly delineated course of action for developing and implementing a Delta/Bay mercury control strategy. Initial steps toward its implementation could begin during this period. Based on the current understanding of issues, some of the key components of the strategy could not be formulated until site specific studies have been completed. This project will develop a consensus on these specific components with respect to what needs to be done and how this information will be used in the strategy.
By mid-second year, several of the CALFED projects as well as projects supported by other sources, should begin to release results that can be incorporated into refining the CALFED mercury management strategy. It will be Dr. Lee's responsibility to develop a review evaluating the adequacy of new information obtained from the literature and from CALFED sponsored research pertinent to the development and implementation of a mercury management strategy. Dr. Lee will incorporate the new information into the revised strategy document as it becomes available. He plans to meet with all interested parties at least quarterly and, more likely, at bi-monthly to monthly intervals to review new developments and refinements of the proposed strategy.
Further, during the second year Dr. Lee will be developing a guideline for monitoring the impacts of mercury input control that can be used at site-specific locations to establish the cost effectiveness of control programs. The monitoring programs will likely incorporate special purpose studies that can provide early indications of ineffective and effective control strategies. This monitoring will likely include studies of bioaccumulation near the mercury source such as in Cache Creek or its tributaries in order to assess if near source controls of mercury input impact the degree of bioaccumulation that is occurring in nearby downstream waterbodies. Since this approach might not be a reliable indicator of what happens in the Delta or Bay, with respect to conversion of a certain form of mercury into bioaccumulatable forms because of the differences in the physical, chemical, and biological characteristics of the water and especially the sediments, it will be important to characterize each of the environments, i.e. near source and Delta/Bay, sufficiently to be able to reliably translate the results from one area to another.
The third year of the project will be devoted to continued modifications of the strategy as new information becomes available and components of the strategy are increasingly implemented. By then, fairly definitive information should be available on the forms of the mercury and various types of sources that will most likely lead to excessive bioaccumulation of mercury in Delta and Bay fish tissue.
Regulatory Requirements for the Control of Mercury
Since the beneficial uses of both the Delta and Bay are impaired due to the excessive mercury concentrations in Delta and Bay fish, the current regulatory requirements mandate that all NPDES regulated point sources of mercury such as domestic and industrial wastewater discharges, control mercury inputs to the Sacramento River, Delta, and Bay so that the concentrations in the discharge do not cause a water quality objective violation in the receiving waters. For NPDES regulated urban and industrial stormwater runoff, the control of mercury in the runoff waters should prevent exceedance of water quality objectives in the receiving waters to the maximum extent practicable using best management practices. The control of mercury input from other non-point sources is less well defined. Basically, it seems to be generally agreed that, for such sources as mine tailings, control should be implemented to the extent that financial resources will allow in order to reduce the impact of the mercury sources on the beneficial uses of the receiving waters by runoff/discharges from these sources. CALFED, therefore, has the option of developing a mercury management strategy that will enable the control of the excessive bioaccumulation that is occurring within Delta and Bay fish focusing on those sources which are the principle sources of bioaccumulatable mercury.
The CVRWQCB has the responsibility of developing a wasteload allocation and total maximum daily loads (TMDL) for mercury input into the Delta as a result of the water quality limitation arising from the mercury caused impairment of the Delta waters. The US EPA, the State Water Resources Control Board, and the Central Valley Regional Water Quality Control Board need assistance in developing guidelines for the formulation of contaminant control programs for toxic and/or bioaccumulatable chemicals. While the US EPA has developed guidance for developing TMDL's for oxygen demand-BOD and nutrients, the agency has not yet developed TMDL guidance for potentially toxic chemicals as well as those that tend to bioaccumulate. Dr. Lee is working with the Santa Ana Regional Water Quality Control Board in formulating approaches for developing TMDL's for toxic chemicals entering upper Newport Bay. This work will include those chemicals that tend to bioaccumulate in upper Newport Bay and its tributary aquatic life, such as mercury. The upper Newport Bay work will have applicability to the mercury management situation in the Delta watershed and Delta.
The CVRWQCB, WRCB, and the US EPA will be invited participants in this project. They will, therefore, have unofficial roles in helping to carry out this project and formulate the CALFED mercury management strategy. The development of this strategy will be fully in accord with current regulatory requirements, and shall anticipate, to the extent possible, changes in these requirements that may arise from revised regulations issued by the US EPA and Congress. Because of the cooperative approach being used in this project, it is anticipated that the recommended CALFED mercury management strategy will be fully implementable from a technical and regulatory perspective.
Additional information pertinent to the Project Description, with emphasis on Technical Justification, is provided as an Appendix. The overall length of this proposal, including this Appendix, conforms to the overall RFP guidelines where the Appendix utilizes some of the Qualifications and Cost and Schedule allowed space.
Costs and Schedule
The proposed budget for the first year of this project is presented in Table 1. The project can be implemented as soon as funds are made available. The anticipated funding levels for the second and third years are the same as for the first. As indicated in Table 1, the CALFED funds will be used to support Dr. Lee's activities presented in the Scope of Work in which he serves as a technical resource and high level technical expertise facilitator and synthesizer of information from the literature and recent and ongoing studies, principally in the Cache Creek watershed into a recommended CALFED mercury management strategy.
Discussion of Budget
Dr. Lee proposes to devote an average of five hours per week on this project for which he will be compensated at less than half of his standard consulting rate for governmental agencies and industry. He has proposed to adjust his normal consulting rate from the current $225 per hour to $100 per hour for this project. He will, therefore, donate in excess $32,000 in support of the development and implementation of the CALFED mercury management program. This contribution will be his cost-share toward the project.
The billing rates for Dr. Lee are rates which include his total costs. The total costs include all costs, except for employee expenses associated with the project and travel costs. There are no overhead/indirect costs, multipliers, fees or separate profit items associated with these rates. Dr. Lee has been active as a consultant to governmental agencies, industry, and others utilizing this approach for budgeting his consulting activities. Since Dr. Lee's activities are primarily that of a consultant to CALFED in the development of a mercury management strategy, it is appropriate to continue this budgeting approach for this project.
While no funds are budgeted for the support of Dr. Anne Jones-Lee (Dr. G. Fred Lee's wife), she will, as needed, be an active participant in the project. Her activities will be primarily focused on providing advice on the aquatic biology/aquatic toxicology components of the project, as well as in the project report preparation. She will donate her time on behalf of the project as needed.
This project will be coordinated with the activities of all others concerned with mercury problems in the Delta and Bay. It will provide the technical leadership for various groups to help formulate local mercury control programs within the Delta watershed. This project is fully compatible with CALFED's objective of providing good water quality for all beneficial uses.
The anticipated milestones for this activity have been presented and discussed under Scope of Work. There are no third party impacts from this project that would require mitigation.
Year One of a Three Year Project
Budget period is one year.
The project can be initiated upon award of contract.
Dr. G. Fred Lee, PhD, DEE
5 hrs/week for one year @ $100/hr. $26,000.00
500 hrs @ $18/hr. 9,000.00
250 hrs @ $15/hr. 3,750.00
Total Personnel $38,750.00
Travel: Miscellaneous travel Sacramento region 500.00
Total Travel and Supplies $5,000.00
Professional Advisory Services
Technical Consultants Honoraria
Three Consultants @ $5,000 per year 15,000.00
Technical Consultants Travel
2 Meetings Per Year
Other Travel Expenses 2,500.00
Technical Consultants Non-Meeting Expenses 2,000.00
Total Technical Consultants $27,000.00
Total Budget: $70,750.00
The anticipated budget for the second and third year of this project are expected to be approximately the same as the first year's budget.
Dr. Lee has a PhD degree from Harvard University obtained in 1960 with an emphasis in environmental engineering, environmental sciences, and aquatic chemistry. He obtained a Master's degree in Public Health in 1957 from the University of North Carolina. For a 30 year period, until 1989, Dr. Lee taught graduate environmental engineering and environmental science courses at several major US universities. During this time, he conducted over five million dollars in research devoted to defining the sources, water quality, and public health significance of chemical constituents in aquatic systems, as well as developing control programs for them. He has published over 650 papers and reports on his work.
Since 1989, he has been a full-time consultant to governmental agencies and industry in the US and other countries in water supply water quality, water and waste water treatment, water pollution control (including mining wastes and Delta water quality issues) and solid and hazardous waste management. For several years in the early 1990's, he was a consultant to the American Dental Association on environmental mercury issues. He is no longer active in that role and does not have a conflict of interests in undertaking this proposed project. He is currently serving as a member of a CVRWQCB Cache Creek Mercury Technical Workgroup. He is also active as a voluntary participant in the Sacramento Watershed Management Program.
A key component of this project is the development of a consensus pertinent to providing guidance on the development of the CALFED mercury control strategy. The development requires that the developer have high expertise in the field and be able to present a discussion of key issues in a issue paper on the topic. These are areas in which Dr. Lee has extensive experience and expertise. One of Dr. Lee's primary interests is working toward the incorporation of good science and engineering into formulation of public policy for water quality management. His extensive past and current publication productivity demonstrates his interest and effectiveness in developing technical materials that can be used to formulate technically valid, cost-effective public policy for environmental quality management.
Further information of Dr. Lee's qualifications to undertake this project has been provided in the Project Description.
Dr. Lee has extensive experience in developing programs of this type and as serving as a member on expert panels on major water quality management issues. Addition information regarding Dr. Lee's expertise and experience pertinent to this project is included in his web site (http://members.aol.com/gfredlee/gfl.htm).
Compliance with Standard Terms and Conditions
Dr. Lee does not anticipate any problems complying with Terms and Conditions set forth in Attachment D to the RFP.
Ecological Significance of Mercury Contamination
While there is a well identified public health problem associated with excessive mercury bioaccumulation in Delta and Bay fish, there may also be ecological problems associated with mercury bioaccumulation and toxicity to aquatic life and terrestrial life (amphibians, mammals and birds) that depend on Delta aquatic resources as food. Although the focus of this project is on the quality of the edible aquatic resources associated with the Delta and Bay (i.e. excessive mercury bioaccumulation in edible fish tissue), there is growing concern about mercury not only being a hazard to human health but also to aquatic life, especially terrestrial life such as animals, birds and amphibians that eat fish or insects that accumulate mercury in their tissue. Current research being conducted by the Fish and Wildlife Service is directed toward examining these issues in the Cache Creek watershed. It is likely that, to the extent that there is an ecological impairment problem associated with the bioaccumulation of mercury in Delta and Bay fish, the results of this project will also have direct applicability to controlling any ecological problems that may exist due to high mercury inputs to the Delta from natural and anthropogenic sources.
Need to Prioritize Remediation Funding
From a water quality management perspective, ideally there would be sufficient funds within CALFED and other organizations to control the mercury and all other potential pollutant inputs to tributaries of the Delta as well as the Delta and Bay from both anthropogenic and natural sources. However, funding restrictions require that the funds available for managing water quality problems associated with the Delta and its tributaries be focused on controlling the water quality use impairment for mercury excessive bioaccumulation in a technically valid, cost-effective manner.
In order for CALFED and other agency funds available for mercury control to be used in a technically valid, cost-effective manner, there is need for a high technical level, organized effort to determine which of the sources of mercury within the Delta watershed contribute mercury to the Delta and Bay in a form that is present in or converted to mercury forms that can bioaccumulate in Delta and/or Bay fish. In addition, CALFED's mercury management program should be based on sufficient understanding of mercury load to the Delta/Bay fish bioaccumulation response relationships to enable an evaluation of the cost-effectiveness of implementing mercury control to various degrees from various sources.
CALFED's funding of this project will enable CALFED to formulate the most technically valid, cost-effective mercury control program that can be developed through near-term, site specific investigations of the potential significance of various forms of mercury from various types of sources as a contributor to the excessive mercury bioaccumulation problem that exists in Delta and Bay fish.
While water quality management programs are sometimes based on factors other than the current state of science and engineering, such as regulatory constraints, CALFED has both the opportunity and the obligation to the public to formulate and implement the most technically valid, cost-effective approach for managing the excessive mercury bioaccumulation problem that is occurring today in Delta and Bay fish. The total magnitude of funding required to control all mercury sources for the Delta to concentrations below those that could potentially lead to excessive bioaccumulation is far greater than the funds available for such control. Further, in addition to the need for funds for mercury control there is also need for funds both for other constituent input control as well and for restoration of the Delta's water quality and ecosystems. Because of the limited funding available compared to the magnitude of Delta problems, it is essential that all Delta water quality management funding be based on properly evaluated water quality problems in which the specific constituents responsible for water quality use impairment are controlled at the sources. This approach will require that CALFED support the development of information that determines bioavailable forms of constituents and their specific sources. With this type of information it will be possible for CALFED to evaluate and prioritize how CALFED funding can and should be spent to maximize water quality improvement in the Delta associated with the mercury pollution problem. This project will provide the information needed by CALFED to develop a mercury control strategy.
This project will focus on the development of information that can address several key technical issues that must be resolved before CALFED can develop a technically valid cost-effective mercury control strategy. The ad hoc mercury group organized by the CVRWQCB staff has had several meetings where mercury issues have been discussed. These discussions have raised questions about the water quality significance of the high flow mercury that enters the Delta each year from the Cache Creek watershed. There are some mercury researchers who express the view that since most of this mercury is apparently in a stable mineral form (cinnibar), the large loads of mercury associated with the high winter/spring flows may have little or no impact on the excessive mercury bioaccumulation problem that occurs within the Delta and Bay. Under these conditions, large amounts of money could be expended controlling the erosion of mercury mine tailings and spent ore deposits and have no impact on the amount of mercury present in edible fish tissue within the Delta and San Francisco Bay.
There are also some researchers who believe that the natural sources of mercury such as the thermal springs in the Cache Creek watershed may be an important source of the mercury that converts to methyl mercury and causes excessive bioaccumulation. If this is the case, then CALFED's funds should be spent developing treatment works for the thermal spring water to remove the mercury from these waters before they enter the larger water courses that eventually reach the Delta.
Some mercury experts express the view that San Francisco Bay and Delta fish may have always had excessive mercury in their tissue compared to current regulatory limits due to natural inputs of mercury to the Delta/Bay. There seems to be considerable consensus among mercury researchers that the existing mercury pool within the Delta and Bay may be sufficient so that the initiation of major control efforts for upstream sources of mercury, such as from former mining activities, may have no impact on the excessive mercury bioaccumulation problem within the Delta and Bay for many decades to hundreds of years or more. If it is concluded from appropriately conducted research that spending large amounts of CALFED money in controlling particulate mercury input to the Delta will likely have little or no impact for very long periods of time on the excessive mercury bioaccumulation problem, then it may be appropriate for CALFED to assign a different priority to control of the high winter/spring flow mercury inputs to the Delta than would be assigned if studies show that there is reasonable likelihood that reducing mercury inputs to the Delta associated with these flows would be expected to cause a discernible impact in the magnitude of the mercury bioaccumulation problem that is occurring in the Delta/Bay.
It is evident that there are several basic issues that must be resolved through appropriately conducted investigations before CALFED can formulate a technically valid, cost-effective strategy for mercury input control. It is important, as part of formulating and implementing a CALFED mercury control strategy, to gain a substantially better understanding of the potential role of each of the mercury sources for the Delta and Bay as a contributor to excessive mercury within the Delta/Bay fish.
One of the initial primary goals of this project will be the development of a discussion of current information on the Delta/Bay mercury problem and the potential sources of mercury that lead to this problem. Dr. Lee will also include in this discussion a review of ongoing research that is relevant to managing the mercury problem in the Delta/Bay. This effort will identify significant information gaps that must be filled in order for CALFED to formulate its mercury control strategy. Dr. Lee will work with the project advisory group to delineate specific research areas that are not currently being addressed to define the significance of mercury from a particular type of source as a cause of excessive bioaccumulation of mercury in Delta/Bay fish. Dr. Lee and the project advisory group will work with CALFED in formulating the components of needed specific research/studies, identifying researchers to carry out the projects and provide technical review of the results during the course of the project and upon completion.
1. Report G. Fred Lee & Associates, El Macero, California, September (1996).
Reference as:"Lee, G.F., 'Urban Pesticide Regulation from the Technical and 'Public's' Perspectives,' G. Fred Lee & Associates, El Macero, CA, March (1998)."
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