7
Ecologic Risk Assessment

INTRODUCTION

The ecologic risk assessment (ERA) for the Coeur d’Alene River basin (CH2M-Hill and URS Corp. 2001) was prepared under contract for the U.S. Environmental Protection Agency (EPA) Region X. The ERA is intended to support the remedial investigation/feasibility study (RI/FS) under the Comprehensive Environmental Response Compensation, and Liability Act (CERCLA) regulatory framework. The purpose of an ERA under CERCLA is to describe the likelihood, nature, and severity of adverse effects to plants and animals resulting from exposure to hazardous substances. In the case of the Coeur d’Alene River basin, the hazardous substances in question represent historic and continuing releases of dissolved and particulate materials from mining operations that have been distributed from the upper and middle basin throughout the study area. The study area addressed in the ERA includes the Coeur d’Alene River and associated tributaries, Lake Coeur d’Alene, and the Spokane River downstream to the Spokane arm of Lake Roosevelt. Although performed under the direction of EPA, the ERA included stakeholder input through the Coeur d’Alene Basin Ecological Risk Assessment Work Group.

EPA used the results of the ERA as inputs to the RI/FS report and the record of decision (ROD) (EPA 2002) for the basin. The ERA addressed risks to plant and animal species exposed to contaminated surface water, sediment, and soil throughout the basin. For contaminated media that were found to pose significant risks, the ERA proposed preliminary remediation



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin 7 Ecologic Risk Assessment INTRODUCTION The ecologic risk assessment (ERA) for the Coeur d’Alene River basin (CH2M-Hill and URS Corp. 2001) was prepared under contract for the U.S. Environmental Protection Agency (EPA) Region X. The ERA is intended to support the remedial investigation/feasibility study (RI/FS) under the Comprehensive Environmental Response Compensation, and Liability Act (CERCLA) regulatory framework. The purpose of an ERA under CERCLA is to describe the likelihood, nature, and severity of adverse effects to plants and animals resulting from exposure to hazardous substances. In the case of the Coeur d’Alene River basin, the hazardous substances in question represent historic and continuing releases of dissolved and particulate materials from mining operations that have been distributed from the upper and middle basin throughout the study area. The study area addressed in the ERA includes the Coeur d’Alene River and associated tributaries, Lake Coeur d’Alene, and the Spokane River downstream to the Spokane arm of Lake Roosevelt. Although performed under the direction of EPA, the ERA included stakeholder input through the Coeur d’Alene Basin Ecological Risk Assessment Work Group. EPA used the results of the ERA as inputs to the RI/FS report and the record of decision (ROD) (EPA 2002) for the basin. The ERA addressed risks to plant and animal species exposed to contaminated surface water, sediment, and soil throughout the basin. For contaminated media that were found to pose significant risks, the ERA proposed preliminary remediation

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin goals (PRGs)1 for use in making remedial decisions at the site. Many of the actions included in the proposed remedy (as documented in the ROD) were specifically intended to reduce or eliminate risks to ecologic resources in the basin. In the statement of task, the committee is directed to assess the adequacy and application of EPA’s Superfund guidance in terms of currently available scientific and technical knowledge and best practices. Specifically, with regard to the Coeur d’Alene River basin site, the committee is to consider the scientific and technical aspects of the following: Assessing the ecologic risk from waste-site contaminants in the context of multiple stressors. The necessary data and appropriate analyses to estimate the ecologic risks attributable to waste-site contaminants—specifically, how well these analyses were applied to estimate the risks, including the effects of lead on migratory fowl. Whether risks attributable to sources other than mining and smelting activities were adequately analyzed. In addressing the charge, this chapter reviews the Coeur d’Alene River basin ERA with respect to the following criteria: Consistency with agency guidance for ERAs Consistency with best scientific practice in ERA Validity of conclusions In addition, the chapter addresses the extent to which the proposed remedy is consistent with the conclusions of the ERA and the likelihood that the selected remedy will significantly improve ecologic conditions in the Coeur d’Alene River basin. In performing its review, the committee found it neither necessary nor appropriate to evaluate all of the underlying scientific studies or to identify all of the aspects of the ERA that could have been improved. The committee recognizes that at a site as large and as obviously disturbed as the Coeur d’Alene River basin, there is no limit to the number or types of data-collection activities that could have been conducted. Similarly, any ERA of the scope and complexity of the Coeur d’Alene River basin ERA could be 1   PRGs are proposed concentrations of materials in soil, sediment, and surface water below which adverse effects are expected to be absent or within defined limits. PRGs are provided to risk managers to assist in making decisions for remedial action (CH2M-Hill and URS Corp. 2001).

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin improved through better data analysis techniques and more thorough documentation. In reviewing this ERA, the committee chose to limit its review to the studies and analyses that were critical to supporting the conclusions and management recommendations. CONSISTENCY OF THE ERA WITH EPA GUIDANCE CONCERNING THE ERA PROCESS EPA’s primary guidance on ERA can be found in the following documents: Guidelines for Ecological Risk Assessment (EPA 1998), Ecological Risk Assessment Guidance for Superfund (EPA 1997), and Ecological Risk Assessment and Risk Management Principles for Superfund Sites (EPA 1999). The Superfund program office has also developed secondary guidance on specific components of Superfund ERAs; all of these are available online. This section of the committee’s report addresses whether or not EPA followed its own guidance in performing the ERA. The technical adequacy of the data and analyses used in the ERA are addressed below (“Evaluation of the ERA in the Coeur d’Alene River Basin”). Description of the ERA Process It must be recognized at the outset that the ERA process followed by EPA is much less explicit than the human health risk assessment process. EPA’s ERA guidance focuses primarily on the process used to design the assessment, evaluate the data, draw conclusions, and communicate the conclusions to risk managers. The overall process consists of the three steps depicted in Figure 7-1. Problem Formulation During problem formulation, the risk assessment team synthesizes information concerning the site being investigated, including the history of activities at the site, nature and spatial scale of the contamination, the types of habitats and organisms exposed, and the fate and effects of the chemicals identified at the site. Risk managers and stakeholders are consulted to identify ecologic management goals for the site. From the management goals and the types of organisms at risk, the risk assessors, risk managers, and stakeholders develop a set of “assessment end points,” which define the specific types of organisms (“entities”) and characteristics (“attributes”) to be addressed in the ERA. An assessment end point for a risk assessment could be a specific fish or wildlife species (for example, bull trout or tundra swan) or a valued habitat type (for example, floodplain lake). Corresponding attributes could include mortality or growth in the case of a species or

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin FIGURE 7-1 ERA process. SOURCE: CH2M-Hill and URS Corp. 2001. plant community composition in the case of a habitat type. Once the assessment end points have been identified, the assessment team develops a conceptual model that shows the causal links between the hazardous substance releases and the assessment end points. A typical conceptual model would include the source of the hazardous substances that have been (or potentially could be) released, the fate and transport pathways through which the assessment end points are (or could be) exposed, and the adverse effects on those end points that are occurring (or could occur) as a result of the exposures. Once the assessment end points and conceptual model have been developed, the risk assessment team develops an analysis plan that identifies the specific types of data needed to complete the assessment and the methods that will be used to analyze the data and draw appropriate conclusions. Analysis During analysis, the risk assessment team implements the analysis plan developed during problem formulation. Depending on the circumstances, analysis may or may not include collection of new data. For chemical stressors, analysis typically is differentiated into separate “exposure” and “effects” components. In exposure analysis, a combination of field measurements and mathematical exposure models are used to estimate spatial

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin and temporal patterns of exposure to the end point species and communities identified in problem formulation. In effects analysis, a combination of literature-derived toxicity information, toxicity tests performed on organisms present at the site, and field studies of the characteristics of exposed individuals, populations, and communities are used to estimate the ecologic effects of chemical exposures. Effects analysis can include development of exposure-response relationships for different types of effects and evaluation of evidence that particular types of adverse effects are caused by the stressor(s) being evaluated. EPA’s guidance documents identify general categories of data and models that could be used in the analysis phase of an ERA, but do not specify which types of data or models should be used for different types of assessments. All such decisions are left to the assessment team, although the team’s decisions ultimately are subject to review both inside and outside the agency. Risk Characterization In this process, the assessment team integrates the results of the exposure and effects analyses and draws conclusions about the magnitude and extent of risk to the end points of concern posed by the stressor(s) being evaluated. At least for chemical stressors, risk characterization includes both a quantitative and a qualitative step. In the quantitative step, termed “risk estimation,” the assessment team develops numerical comparisons between exposure concentrations or doses and exposures expected to cause adverse effects. The comparisons are most often deterministic—for example, comparisons between mean or maximum exposure concentrations and single-valued toxicity benchmarks such as the lowest-observed-effect levels (LOELs). The comparison also can be probabilistic, where the exposure estimate, the effects estimate, or both are expressed as a probability distribution. Probabilistic methods are often used to estimate the fraction of an exposed population that may be exposed to a concentration or dose higher than a given toxicity benchmark. Probabilistic methods may also be used to develop risk curves that show probabilities of effects of differing magnitude. If population- or community-level risks are being addressed, a mathematical model of population or community dynamics may be used to express the risk in terms of higher-level effects such as percent reduction in abundance, increased risk of extinction, and change in community composition. It should be noted that none of these techniques are specifically required by either the agency-wide guidelines or the Superfund guidance. The choice of which techniques will be used is left to the risk assessment team and the responsible project manager and is normally documented in a work plan prepared prior to the initiation of data collection.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin The qualitative phase of risk characterization, which is termed “risk description” in the agency-wide guidelines, involves interpreting the magnitude, significance, and management implications of the quantitative risk estimates. Where multiple lines of evidence have been developed, risk description involves reconciling any inconsistencies between different types of evidence. In the case of Superfund ERAs, risk characterization also includes the development of PRGs intended to aid risk managers in designing an appropriate and effective remedy. PRGs are estimates of concentrations in environmental media that are expected to protect biota at the site from adverse effects of chemical exposure. The Superfund guidance recommends that both lower-bound and upper-bound values should be developed for each environmental medium of concern. The lower bound would be based on consistent conservative assumptions and no-observed-adverse-effects levels (NOAELs). Contaminant concentrations as low or lower than this lower bound should cause no adverse ecologic effects. The upper bound would be based on observed or predicted impacts and would be developed using less-conservative assumptions, site-specific data, lowest-observed-adverse-effects levels (LOAELs), or an impact evaluation. Contaminant concentrations as high or higher than the upper bound could cause adverse ecologic effects. Evaluation of the ERA in the Coeur d’Alene River Basin The following subsections evaluate EPA’s ERA for the Coeur d’Alene River basin with respect to consistency with agency guidance. Problem Formulation Section 2 of the ERA, which documents the problem-formulation step, begins with a statement of management objectives and then derives assessment end points from those objectives and develops a conceptual model. The management objectives were developed with input from an ERA work group consisting of representatives of the states of Idaho and Washington; the Coeur d’Alene, Spokane, and Colville tribes; the U.S. Fish and Wildlife Service; and any other governmental or nongovernmental organizations that wished to participate. Contaminants of potential ecologic concern (COPECs) were selected using a two-step procedure. In the first step, the available data on concentrations of chemicals in soil, sediment, and surface water were subjected to a data-quality review. Resultant values were then screened against soil/ sediment background levels and ambient water-quality criteria (AWQC). The assessment end points include individual species, biological communities, and physical habitat characteristics that could be adversely af-

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin fected by mining-related hazardous substances. Taxonomic groups of organisms addressed included birds, mammals, fish, amphibians, and plants. Representative species belonging to each group were identified for each Conceptual Site Model (CSM)2 unit and habitat type. The measures of mining-related effects selected for evaluation included reductions in survival, reproduction, growth, and abundance. For migratory birds and “special status” species (that is, threatened, endangered, or culturally significant species, or state or agency species of special concern) effects of mining-related hazardous substances on the health of individual organisms were also evaluated. For migratory birds and special status species, effects were considered to be adverse if any of the attributes of interest was observed or predicted to be adversely affected. For other species, effects were considered adverse only if a 20% or greater adverse change in an attribute of interest was observed or predicted. The use of a 20% effects level as a default de minimis criterion for ecologic significance was first proposed by Suter et al. (1995), on the grounds that this value is consistent both with EPA’s regulatory practices and with the practical detection limits of typical toxicity testing protocols and field survey methods. In addition to evaluating effects of mining-related hazardous substances on individual species, the ERA also evaluated effects on aquatic and terrestrial plant and invertebrate communities, soil processes, and physical/ biological characteristics. Community-level effects addressed included effects on community composition, abundance, density, species diversity, and community structure. Physical/biological characteristics evaluated included habitat suitability indices, spatial distributions of healthy riparian communities, sediment deposition rates, and turbidity. Changes in these characteristics were addressed to account for secondary effects of hazardous substance releases (for example, degradation of riparian habitat resulting from toxic effects of hazardous substances on vegetation). Section 2 concludes with lists of COPECs and receptor species to be evaluated. Separate lists of COPECs are provided for each medium, and separate lists of receptors are provided for each of six habitat types present in the basin. The one component that is not included in the ERA is an analysis plan. Such a plan would normally be developed at the conclusion of the problem-formulation phase of an ERA. Data gaps identified during the development of the analysis plan would then be filled prior to implemen- 2   The study area was divided into five CSM units in the ERA. These roughly correspond to the high-gradient watersheds in the upper (eastern) basin (CSM 1), the mid-gradient water-sheds in the middle basin (CSM 2), the expansive depositional floodplain and lateral lakes area in the lower basin (CSM 3), Lake Coeur d’Alene (CSM 4), and the Spokane River (CSM 5); see Chapters 3 and 4 of this report for further discussion.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin tation of the remaining steps in the ERA. The rationale for bypassing the analysis plan (CH2M-Hill and URS Corp. 2001, pp. 1-3 to 1-4) was that a large number of investigations had already been performed within the Coeur d’Alene River basin. These investigations included sampling of environmental media and biological tissues, bioavailability tests and toxicity tests to a wide variety of biota, and numerous biological surveys. As documented in Appendix A to the ERA, EPA used a series of workshops and meetings with stakeholders to identify additional data needs. It is possible that some of the methods used in the ERA may have been selected because they were consistent with existing data rather than because they were the best approach for quantifying risks to the assessment end points. Also, because the expansion of the Superfund site vastly increased the geographic extent of the site, ecologic effects in some areas may have been incompletely described. Although in most respects the problem formulation step of the Coeur d’Alene River ERA appears to be consistent with the requirements of guidance, the failure to develop an analysis plan may have contributed to the continued existence of data gaps (discussed later in this chapter) that limit the value of the ERA results for guiding remedy design. Analysis Section 3 of the ERA, which documents the analysis phase of the risk assessment, provides information on the measures of exposure and effects used in the ERA. For the exposure analysis, Section 3 identifies, for each CSM unit and habitat type, the routes by which each receptor could be exposed to the COPECs identified in the problem-formulation step. Data on COPEC concentrations in each medium serving as a source of exposure were summarized. For aquatic biota and soil invertebrates, the media concentrations provide direct estimates of exposure. Because wildlife receptors can be exposed to COPECs via direct and indirect pathways (ingestion of soil/ sediment, water, and contaminated biota), the exposure assessment for these receptors used models to quantify multimedia exposures to COPECs. The data and models used are documented in Appendices A-D of the ERA. The effects analysis utilized available data derived from published literature on the toxicity of individual COPECs to terrestrial and aquatic biota; tests of the toxicity of soil, sediment, and water collected in the Coeur d’Alene River basin; laboratory dosing studies performed to simulate waterfowl exposures to COPECs; and field studies performed in the basin. The toxicity data were used to define, for each receptor, a range of toxicity reference values (TRVs) for comparison with the estimated exposure concentrations or doses from the exposure analysis. Data sets and procedures

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin used to develop these TRVs are documented in Appendices E and F of the ERA. All the data and exposure models used in the analysis phase are identified in guidance as being appropriate for use in ERA; hence, Sections 3 and 4 of the ERA also appear to be consistent with available guidance. Risk Characterization The risk characterization section of the ERA (Section 4) synthesizes the exposure and effects analyses documented in Section 3. Both a risk estimation and a risk description component are included. In the risk estimation step, the exposure estimates for each receptor were compared with the TRVs documented in Section 3. For birds, mammals, and aquatic biota, point estimates of exposures were compared with point estimates of effects. For amphibians, terrestrial plants, soil invertebrates, and soil processes, full distributions of exposure and effects estimates were compared, with the risk represented by the percent overlap of the two distributions. Risk estimates derived from site-specific toxicity tests and field surveys were evaluated by comparison with reference conditions. All of the techniques used are identified in the agency-wide guidelines and in the Superfund guidance as being valid risk-estimation techniques. The risk description evaluated all the lines of evidence for each receptor group. Greater weight was given to site-specific toxicity tests and field surveys than to risk estimates based on literature-derived toxicity data. Strength of risk conclusions was considered high if multiple lines of evidence, including site-specific field surveys and toxicity tests, were available for a given receptor and all lines of evidence were in agreement. Risk conclusions were considered to be of moderate strength if the data consisted of literature-based toxicity and one other line of evidence. If only literature-based toxicity data were available, the strength of risk conclusions was rated as low. For each habitat, the risk characterization identified the receptors at risk and the COPECs posing the greatest potential risk to each receptor. The risk description section of the ERA also includes a qualitative evaluation of secondary effects of mining-derived hazardous substances on habitat quality. Uncertainties affecting all components of the risk assessment are summarized in a separate section on uncertainty analysis. Risk calculations are documented in Appendices G-I of the ERA. These calculations appear to be consistent both with the formal requirements of guidance and with the procedures for risk characterization documented by Suter et al. (2000). As discussed later in this chapter, the PRGs for aquatic organisms in sediment and water provided in the ERA are lower-bound thresholds as

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin defined in the Superfund guidance. No upper-bound thresholds are provided in the ERA. In this respect, the risk characterization component of the ERA does not conform to the Superfund guidance. In all other respects, EPA’s risk characterization is consistent with agency guidance. CONSISTENCY OF THE ERA WITH BEST SCIENTIFIC PRACTICE EPA guidance on ERAs focuses on procedures rather than on the quality or quantity of the data and models used. Therefore, beyond considering consistency with guidance, it is also necessary to evaluate, from a technical perspective, whether the assessment was properly designed and conducted and whether the conclusions are adequately supported. This section of the committee report evaluates the consistency of the ERA with best scientific practice in ERA. The question here is not whether EPA guidance was followed but whether the site-specific studies performed to support the assessment were properly designed and conducted and whether the supporting scientific literature was properly interpreted. Problem Formulation Range of Stressors Evaluated All the stressors evaluated as COPECs are mining-related metals. Section 2.4 of the ERA report discusses the data and methods used to select COPECs for the ERA. The process involved examining all data available both from historical investigations and from sampling conducted specifically to support the RI/FS. These sources are summarized in Table 2-9 of the ERA report (CH2M-Hill and URS Corp. 2001). Media evaluated included soil, sediment, water, and biological tissues. Evaluation of the data included a data-quality review, data reduction, and association of sampling locations with CSM units and habitat types. Zinc is clearly the metal with the largest ongoing discharges in the Coeur d’Alene River basin, followed by lead and cadmium. Most zinc and cadmium are released and transported as dissolved metals. Most lead is present in particulate form and is transported with sediment, especially during flood events. As a result of historical flood events, particulate lead has been deposited in streambeds, lakes, riparian zones, and floodplains throughout the lower basin, Lake Coeur d’Alene, and the Spokane River. Based on the environmental concentration data and comparisons to screening levels, as described above, the selection of COPECs was reasonable. Non-mining-related stressors were not explicitly considered in the ERA. These types of stressors include habitat modification, infrastructure development (roads and railways), and stream channelization. Mining-related

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin stressors besides metals, particularly sediments associated with mining and milling activities that were released to streams in vast quantities, also were not explicitly addressed in the ERA. As stated in the ERA (CH2M-Hill and URS Corp. 2001, p. 2-39), The EcoRA [ecologic risk assessment] does not attempt to quantify the relative effects of mining activities and other stressors. As part of the natural resource damage assessment (NRDA) process, a determination and initial quantification of mining-related injury to natural resources has been completed. Some mention is made of the potential effects from non-mining-related stressors. Figure 2-16 in the ERA illustrates how non-mining-related stressors could affect the receptors evaluated in this ERA and identifies resource management, fire, waterborne log transport, watershed management, roads and railroads, hydraulic modification, housing and urban development, and septic/waste disposal systems as potential non-mining-related stressors. Appendix K of the ERA, which evaluates the secondary effects of mining-related hazardous substances (for example, loss of riparian habitat and stream bank stability), concludes that non-mining-related stressors (development, road building) also contribute to these secondary effects, but the relative contribution of mining-related hazardous substances (presumably metals) and other stressors cannot be quantified. According to the ERA (CH2M-Hill and URS Corp. 2001, p. 2-40), physical disturbances unrelated to mining were accounted for in the ERA by comparing site-specific information on biota and habitats from mining-affected areas with information on biota and habitats from non-mining-affected reference areas believed to be affected by the same types of non-mining-related disturbances. The consideration of areas with similar levels of infrastructure as a reference is appropriate, especially in light of the preponderance of evidence relating to the ecologic effects of metals in the Coeur d’Alene River basin environments. Because the purpose of ERAs performed at Superfund sites is to evaluate risks associated with releases of hazardous substances, the focus on metals as stressors is reasonable. Impacts of physical disturbances, including non-mining-related disturbances, would still have to be considered during remedy selection and implementation, but they need not be explicitly addressed during the risk assessment component of the RI/FS process. Characterization of Existing Ecologic Conditions The Coeur d’Alene River basin is a complex ecologic zone consisting of the Coeur d’Alene River and tributaries, lateral lakes, Lake Coeur d’Alene, and the Spokane River. The question is, was a reasonable survey conducted

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin criterion was recommended as the PRG for each CSM unit. For sediment, the higher of either background or NOAA’s screening value was recommended as the PRG. The PRGs for terrestrial wildlife are well documented, although based only in part on site-specific data. They appear to be consistent with EPA guidance, although the high reliance on literature-derived TRVs for many species contributes substantial uncertainty to the calculated values. The PRGs for aquatic biota, and especially for sediment, appear more questionable and do not appear to be consistent with EPA guidance. For surface water, the AWQC are potentially applicable or relevant and appropriate requirements (ARARs) and for this reason should be included as PRGs. However, by definition, the criteria are intended to protect at least 95% of exposed aquatic species. As long as the AWQC are not exceeded, no ecologicly significant adverse effects should occur. Exceedance of the criteria, however, does not imply that adverse effects will occur. Figures 3-23 through 3-30 of the ERA compare the AWQCs for cadmium, copper, lead, and zinc with acute and chronic effects concentrations derived from various published sources. In all cases, AWQC fall near or below the lowest published effect value. Hence, although the AWQC provide a lower-bound PRG value as defined in EPA guidance, they may not be suitable as an upper bound. For sediment, the ERA does not provide a rationale for using the NOAA screening values as PRGs. All the values used are “threshold effects levels,” which are estimates of the lowest values at which adverse effects might occur. These values might be suitable as lower-bound PRGs, but they clearly are inappropriate as upper-bound PRGs or as the only PRGs recommended for use in risk management. Use of PRGs in Defining the Proposed Remedy The ecologic PRGs are reproduced in the ROD (EPA 2002, Tables 7.2-6 to 7.2-9) and characterized as being concentrations that are “protective” of terrestrial and aquatic biota. However, with the exception of the AWQC values, it does not appear that any of these values were actually used in remedy selection. As discussed in Section 8 of the ROD, the AWQC were considered to be potential ARARs and, for this reason, were identified as long-term cleanup benchmarks. Although the ERA developed wildlife PRGs for five chemicals of concern, lead was the only chemical used in defining the remedy for soil/sediment. The value selected as the remediation benchmark, 530 mg/kg, is within the range of PRG values identified in the ERA. This value is the LOAEL from a modeling study that incorporates laboratory and field components (Beyer et al. 2000). This study developed an exposure model that described a lowest-effect level of lead as 530 mg/kg in sediments, a reasonable number based on the science to date (see Box 7-3).

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin BOX 7-3 Relating Sediment Lead Concentrations to Waterfowl Effects—Derivation of the Cleanup Criterion in the Lower Basin EPA heavily relied on one study in particular in decisions relating to the toxicity of metals-contaminated sediments to waterfowl and determination of a remedial goal for the protection of waterfowl. Beyer et al. (2000) reported on studies of waterfowl experimentally fed sediments from the Coeur d’Alene River basin and compared their results with field studies conducted in the basin to relate sediment lead concentration to injury to waterfowl. The first step in their model development involved the relation of sediment lead concentration to blood concentration in mute swans (Cygnus olor), and these data were compared with sediment ingestion estimated from analyses of feces of tundra swans (Olor columbianus), migratory residents in the Coeur d’Alene River basin. With additional laboratory studies on Canada geese (Branta canadensis) and mallards (Anas platyrhynchos) fed sediment contaminated with lead, a general relation of blood lead to injury in waterfowl was developed. By integrating the exposure and injury relations, the no-effect concentration of sediment lead was estimated as 24 mg/kg, and the lowest effect level was estimated as 530 mg/kg (based on reduced -aminolevulinic acid dehydratase activities). Beyer et al. then combined their exposure equation with data on blood lead concentrations measured in lead-intoxicated tundra swans in the basin and estimated that some mortality would occur at a sediment lead concentration as low as 1,800 mg/kg. EPA made a risk management decision to use the site-specific protective value lead concentration of 530 mg/kg as the benchmark cleanup criterion for the soil and sediment in the lower basin for protection of waterfowl. Although the value was not derived from the extensive analyses conducted in the ERA (and reviewed in this report), it does fall within the estimated range of sediment lead concentrations protective of aquatic birds and mammals that was determined in the ERA. This value is supported by substantial field evaluation of lead effects on waterfowl in the Coeur d’Alene River basin, as reported by Henny et al. (2000) and in particular a report by Blus et al. (1999), reporting substantial lead toxicity in tundra swans captured in the Coeur d’Alene River basin. However, no specific justification for the use of this value rather than a NOAEL or some other value is provided in the ROD (also see Chapter 8, Ecologic Risks: Rationale for Determining Levels of Remediation). The sediment PRGs do not appear to have been used at all in remedy selection. For surface waters, rather than relying on the PRGs, remedy selection appears to have been based on a set of “interim fishery benchmarks” (URS Greiner and CH2M Hill 2001c) that were developed outside the ERA process. These benchmarks, which are discussed in greater detail in Chapter 8 of the committee’s report, identify interim remediation targets in terms of desired characteristics of the fish community in different stream reaches

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin and metal concentrations expected to support fish communities of the desired types. No explanation is provided in the ROD concerning why the PRGs played such a small role in the development of the proposed interim remedy. Reliance on a study performed externally to the ERA appears quite remarkable to the committee, given the extraordinary length and degree of detail concerning ecologic risks provided in the ERA report. It seems likely to the committee that a principal reason for the failure of the ROD to make greater use of the ERA in design of the remedy is that the ERA focused almost exclusively on exhaustive documentation of the presence or absence of risks. Documentation of risks due to chemical exposure and estimation of chemical concentrations that would eliminate those risks is, in fact, all that EPA guidance on ERA requires. If the ERA had been designed differently, it could have been a source of performance metrics and restoration goals for use in implementing EPA’s proposed adaptive approach to remediation. Failure to provide these types of essential outputs reflects, in the committee’s opinion, a failure both of EPA’s guidance and of EPA’s decision to rely on existing data to complete the ERA. Importance of Habitat Impairment Relative to Chemical Toxicity Habitat degradation occurring as a secondary effect of mining activities is discussed both in the ERA and in the ROD. Qualitative PRGs for riparian, riverine, and lacustrine habitat are recommended in the ERA. The PRGs (CH2M-Hill and URS Corp. 2001, Table 5-11) for each habitat type and physical characteristic state that the habitat should be returned either to pre-mining conditions or to a condition similar to conditions found in selected reference areas that are only affected by non-mining related disturbances. These PRGs were listed in the ROD (EPA 2002, Table 7.2-10) but were not used to define remediation benchmarks. Despite the abundant evidence of harm caused by zinc and other dissolved metals, there is clear evidence that channel alterations also impaired fish populations in the Coeur d’Alene River (Dunham and others 2003; Wesche 2004). Wesche, using his own sampling and literature data, estimates that 40-80% of the habitat in the South Fork is degraded for trout and concludes that it is habitat limitation that precludes a healthy trout fishery in the South Fork. Substantial channel alterations have occurred in the upper South Fork for the purposes of flood control, remediation, and road building. Historically, much of the floodplain of the South Fork of the Coeur d’Alene River was forested, particularly with large cedars. The forested condition would have led to decreased stream temperatures, increased stream bank stability, and increased habitat complexity, conditions that support high-quality fish and macroinvertebrate communities. These types

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin of habitats no longer exist along the South Fork. These alterations are clearly permanent and may well limit the recovery of aquatic communities in the river, even if all applicable AWQC are met. The conflict between the goal of returning the river to pre-mining conditions and the irreversible effects of urbanization are not discussed in either the ERA or the ROD. CONCLUSIONS AND RECOMMENDATIONS Conclusion 1 The ERA is generally consistent with EPA guidance concerning the ERA process, however, EPA’s decision to rely on existing data limits the value of the ERA for risk management. All except one of the components (a data analysis plan) of an ecologic risk assessment as discussed in guidance are included in the assessment. Stakeholders were appropriately involved in planning and implementing the assessment and data selection and evaluation procedures prescribed in EPA’s data quality objectives guidance were followed. The results of the assessment were appropriately documented and the PRGs that were developed were consistent with the conclusions of the risk assessment. However, during the problem formulation phase of the ERA, EPA and the other stakeholders chose to bypass the development of an analysis plan and to rely on existing data to complete the ERA. If an analysis plan had been developed, some of the significant data gaps noted in this review could have been filled, and the utility of the ERA for risk management could have been substantially improved. Conclusion 2 The ERA is generally consistent with best scientific practice in ERA. In some respects (for instance, the selection of representative species and development of literature-derived TRVs) it was more extensive and detailed than are many ERAs. However, there were some potentially significant exceptions that limit the adequacy of the ERA for supporting appropriate remedial actions. Assessments for birds (except waterfowl) and mammals were limited to comparisons between modeled dose estimates and literature-derived effects benchmarks. These methods are highly uncertain (although they are widely used in risk assessments). The evaluation of benthic invertebrates in the risk assessment included only limited measures of community structure and site-specific toxicity tests. An integrated laboratory and field study designed specifically to

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin support the ERA could have provided a much stronger foundation for risk management decision making. The risk assessment for Lake Coeur d’Alene is not supported by any defined, quantitative study linking metal concentrations in sediments or in the overlying waters to biotic communities despite ample evidence of the presence of elevated metal concentrations. The lack of data precludes an assessment. Conclusion 3 Support for the ERA’s conclusions is strongest with respect to waterfowl (lead) and fish (zinc and other dissolved metals); support for conclusions about other receptors is much more uncertain. The waterfowl and fish assessments are supported by multiple lines of evidence, including site-specific data that reflect effects of multiple contaminants. The conclusions concerning risk to waterfowl are especially strong because of the wealth of data on dose-response relationships developed by USGS and the U.S. Fish and Wildlife Service. Conclusions about risks to fish are also well supported, although some uncertainty exists with respect to chemical-specific values because fish within the basin are exposed to multiple chemicals. Conclusions about risks to other receptors are uncertain because of reliance on models and literature-derived toxicity data for single-chemical exposures. Conclusion 4 The level of support for PRGs is highly variable among receptors. The range of PRGs for waterfowl is very strongly supported. The PRGs for fish, benthic invertebrates, small mammals, plants, amphibians, and birds other than waterfowl are uncertain, and their value for guiding remediation decisions is questionable. All these are based on regulatory criteria, literature-derived TRVs (many of which are highly conservative), and background concentrations rather than site-specific toxicity data. For fish and benthic invertebrates, only lower-bound PRGs are provided. Conclusion 5 Despite the large number of ecologic studies performed in the basin and the complexity of the analyses provided in the ERA report, the results of the ERA had only a minimal apparent influence on the ROD.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin Of the many PRGs developed in the ERA, only the national AWQC were adopted as remediation goals in the ROD. Only one remediation goal, the soil/sediment goal for lead, was based on site-specific data. Instead of basing the interim remediation goal for dissolved metals on the ERA results, the ROD relied on a set of “interim fishery benchmarks” that were developed outside the ERA process. Recommendation 1 Further research is needed to support remedial actions intended to promote recovery of aquatic and terrestrial biota within the basin. Information is particularly lacking on effects to benthic invertebrate and fish communities in the lower basin, the magnitude and spatial extent of risks to riparian and upland communities, and the condition of benthic communities in Lake Coeur d’Alene in relation to contaminated sediments. Recommendation 2 Further research is needed on the influence of transport and transformation processes on the fluxes and bioavailability of particulate lead and dissolved metals. Improved understanding of these processes is needed to ensure the effectiveness of remedial actions intended to reduce risks to wildlife and aquatic biota. Recommendation 3 ERAs at large, complex sites like the Coeur d’Alene River basin should be designed to support remedy selection and not simply to document the presence or absence of risks. In particular, the ERA should be a source of performance metrics and restoration goals for use in adaptive restoration of the basin. EPA’s guidance on Superfund ERAs should be modified to encourage the development of performance goals and metrics as part of ERAs for large, complex sites such as the Coeur d’Alene River basin. Recommendation 4 In developing performance metrics and restoration goals, additional consideration should be given to development-related habitat modifications (for example, stream channelization) that may prevent a return to premining conditions. Remedial activities designed to reduce metals exposure and transport should, to the extent practicable, concomitantly strive to improve habitat for fish and wildlife.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin REFERENCES Audet, D.J., L.H. Creekmore, L. Sileo, M.R. Snyder, J.C. Franson, M.R. Smith, J.K. Campbell, C.U. Meteyer, L.N. Locke, L.L. McDonald, T.L. McDonald, D. Strickland, and S. Deeds. 1999. Wildlife Use and Mortality Investigation in the Coeur d’Alene Basin 1992-97. Final Draft. U.S. Fish and Wildlife Service, Spokane, WA, U.S. Geological Survey, Biological Resources Division, National Wildlife Health Center, Madison, WI, and Western EcoSystems Technology, Cheyenne, WY. May 24, 1999. Beckwith, M.A. 1996. Water-quality Data Collected During Floods in the Coeur d’Alene River, Northern Idaho, February 1996. U.S. Geological Survey Fact Sheet FS-219-96. Reston, VA: U.S. Geological Survey. Beyer, W.N., D.J. Audet, G.H. Heinz, D.J. Hoffman, and D. Day. 2000. Relation of waterfowl poisoning to sediment lead concentrations in the Coeur d’Alene River Basin. Ecotoxicology 9(3):207-218. Blus, L.J., C.J. Henny, D.J. Hoffman, L. Sileo, and D.J. Audet. 1999. Persistence of high lead concentrations and associated effects in tundra swans captured near a mining and smelting complex in northern Idaho. Ecotoxicology 8(2):125-132. Bookstrom, A.A., S.E. Box, J.K. Campbell, K.I. Foster, and B.L. Jackson. 2001. Lead-Rich Sediments, Coeur d’Alene River Valley, Idaho: Area, Volume, Tonnage, and Lead Content. U.S. Geological Survey Open-File Report 01-140. Menlo Park, CA: U.S. Department of the Interior, U.S. Geological Survey [online]. Available: http://geopubs.wr.usgs.gov/open-file/of01-140/ [accessed Dec.1, 2004]. Campbell, J.K., D.J. Audet, J.W. Kern, M. Reyes, and L.L. McDonald. 1999. Metal Contamination of Palustrine and Lacustrine Habitats in the Coeur d’Alene Basin, Idaho. U. S. Fish and Wildlife Service, Spokane, WA, and Western EcoSystems Technology, Inc., Cheyenne, WY. May 24, 1999. CH2M-Hill and URS Corp. 2001. Final Ecological Risk Assessment: Coeur d’Alene Basin Remedial Investigation/Feasibility Study. URS DCN: 4162500.06200.05.a2. CH2M Hill DCN: WKP0041. Prepared for U.S. Environmental Protection Agency, Region 10, Seattle, WA, by CH2M Hill, Bellevue, WA, and URS Corp., White Shield, Inc., Seattle, WA. May 18, 2001. Chupp, N.R., and P.D. Dalke. 1964. Waterfowl mortality in the Coeur d’Alene River Valley, Idaho. J. Wildl. Manage. 28(4):692-702. Connor, E.E., P.F. Scanlon, and R.L. Kirkpatrick. 1994. Bioavailability of lead from contaminated sediment in northern bobwhites, Colinus virginianus. Arch. Environ. Contam. Toxicol. 27(1):60-63. Di Toro, D.M., H.E. Allen, H.L. Bergman, J.S. Meyer, P.R. Paquin, and R.C. Santore. 2001. Biotic ligand model of the acute toxicity of metals. 1. Technical basis. Environ. Toxicol. Chem. 20(10):2383-2396. Dunham, J., B. Rieman, and G. Chandler. 2003. Influences of temperature and environmental variables on the distribution of bull trout within streams at the southern margin of its range. N. Am. J. Fish. Manage. 23(3):894-904. Efroymson, R.A., M.E. Will, and G.W. Suter. 1997a. Toxicological Benchmarks for Contaminants of Potential Concern for Effects on Soil and Litter Invertebrates and Heterotrophic Process: 1997 Revision. ES/ER/TM-126/R2. Prepared for the U.S. Department of Energy, Office of Environmental Management, by the Environmental Restoration Risk Assessment Program, Lockheed Martin Energy Systems, Inc. Oak Ridge, TN: Oak Ridge National Laboratory [online]. Available: http://www.hsrd.ornl.gov/ecorisk/tm126r21.pdf [accessed July 1, 2005].

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin Efroymson, R.A., M.E. Will, G.W. Suter, and A.C. Wooten. 1997b. Toxicological Benchmarks for Screening Contaminants of Potential Concern for Effects on Terrestrial Plants: 1997 Revision. ES/ER/TM-85/R3. Prepared for the U.S. Department of Energy, Office of Environmental Management, by the Environmental Restoration Risk Assessment Program, Lockheed Martin Energy Systems, Inc. Oak Ridge, TN: Oak Ridge National Laboratory [online]. Available: http://www.hsrd.ornl.gov/ecorisk/tm85r3.pdf [accessed July 1, 2005]. EPA (U.S. Environmental Protection Agency). 1997. Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessments. EPA/ 540-R-97-006. Office of Solid Waste and Emergency Response, U.S. Environmental Protection Agency, Washington, DC [online]. Available: http://www.epa.gov/superfund/programs/risk/ecorisk/ecorisk.htm [accessed Jan. 25, 2005]. EPA (U.S. Environmental Protection Agency). 1998. Guidelines for Ecological Risk Assessment. EPA/630/R-95/002F. Risk Assessment Forum, U.S. Environmental Protection Agency, Washington, DC [online]. Available: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=12460 [accessed Jan. 25, 2005]. EPA (U.S. Environmental Protection Agency). 1999. Issuance of Final Guidance: Ecological Risk Assessment and Risk Management Principles for Superfund Sites. OSWER Directive 9285.7-28P. Memorandum to Superfund National Policy Managers Regions 1-10, from Stephen D. Luftig, Director, Office of Emergency and Remedial Response, U.S. Environmental Protection Agency, Washington, DC. October 7, 1999 [online]. Available: http://www.epa.gov/oswer/riskassessment/superfund_management.htm [accessed Oct. 12, 2005]. EPA (U.S. Environmental Protection Agency). 2002. The Bunker Hill Mining and Metallurgical Complex: Operable Unit 3, Record of Decision. U.S. Environmental Protection Agency, Region 10. September 2002 [online]. Available: http://yosemite.epa.gov/.../cbc45a44fa1ede3988256ce9005623b1/$FILE/ATTBRN4D/Part%201%20Declaration.pdf [accessed Dec. 1, 2004]. EPA (U.S. Environmental Protection Agency). 2004. EPA Responses to NAS Questions (April 15, 2004). EVS (EVS Environment Consultants). 1996a. State of Idaho Technical Memorandum—Results of Range-Finding Tests. Preliminary Draft. EVS Project No. 2/654-03. Prepared for Idaho Division of Environmental Quality, Coeur d’Alene, ID, by EVS Environment Consultants, Inc., Seattle, WA. December 1996. 45 pp [online]. Available: http://www.nic.edu/library/superfund/refdocs%5Ccda0149.pdf [accessed Jan. 25, 2005]. EVS (EVS Environment Consultants). 1996b. State of Idaho Site-Specific Toxicity Testing Methods for the South Fork Coeur d’Alene River—Results and Recommendations. Prepared for Idaho Division of Environmental Quality, Coeur d’Alene, ID, by EVS Environment Consultants, Inc., Seattle, WA. Farag, A.M., D.F. Woodward, J.N. Goldstein, W. Brumbaugh, and J.S. Meyer. 1998. Concentrations of metals associated with mining waste in sediments, biofilm, benthic macroinvertebrates, and fish from the Coeur d’Alene River basin, Idaho. Arch. Environ. Contam. Toxicol. 34(2):119-127. Farag, A.M., D.F. Woodward, W. Brumbaugh, J.N. Goldstein, E. McConnell, C. Hogstrand, and F. Barrows. 1999. Dietary effects of metals-contaminated invertebrates from the Coeur d’Alene River, Idaho, on cutthroat trout. Trans. Am. Fish. Soc. 128(4): 578-592.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin Funk, W.H., F.W. Rabe, R. Filby, G. Bailey, P. Bennett, K. Shah, J.C. Sheppard, N. Savage, S.B. Bauer, A. Bourg, G. Bannon, G. Edwards, D. Anderson, P. Syms, J. Rothert, and A. Seamster. 1975. An Integrated Study on the Impact of Metallic Trace Element Pollution in the Coeur d’Alene-Spokane Rivers and Lake Drainage System. Project Completion Report to OWRT (Title II Project C-4145). Washington State University and University of Idaho. 332 pp. Griffith, M., J.M. Lazorchak, and A.T. Herlihy. 2004. Relationships among exceedences of metals criteria, the results of ambient bioassays, and community metrics in mining-impacted streams. Environ. Toxicol. Chem. 23(7):1786-1795. Heinz, G.H., D. J. Hoffman, L. Sileo, D.J. Audet, and L.J. LeCaptain. 1999. Toxicity of lead-contaminated sediments to mallards. Arch. Environ. Contam. Toxicol. 36(3):323-333. Henny, C.J., L.J. Blus, D.J. Hoffman, L. Sileo, D.J. Audet, M.R. Snyder. 2000. Field evaluation of lead effects on Canada geese and mallards in the Coeur d’Alene River Basin, Idaho. Arch. Environ. Contam. Toxicol. 39(1):97-112. Hoffman, D.J., G.H. Heinz, L. Sileo, D.J. Audet, J.K. Campbell, and L.J. LeCaptain. 2000. Developmental toxicity of lead-contaminated sediment to mallard ducklings. Arch. Environ. Contam. Toxicol. 39(2):221-232. Honda, K., D.P. Lee, and R. Tatsukawa. 1990. Lead poisoning in swans in Japan. Environ. Pollut. 65(3):209-218. Hornig, C.E., D.A. Terpening, and M.W. Bogue. 1988. Coeur d’Alene Basin-EPA Water-quality Monitoring (1972-1986). EPA 910/9-88-216. PB89-217962. U.S. Environmental Protection Agency, Region 10, Seattle, WA. September. Horowitz, A.J., K.A. Elrick, and R.B. Cook. 1993. Effect of mining and related activities on the sediment trace element geochemistry of Lake Coeur d’Alene, Idaho, USA. Part I: Surface sediments. Hydrol. Process. 7:403-423. Horowitz, A.J., K.A. Elrick, J.A. Robbins, and R.B. Cook. 1995. Effect of mining and related activities on the sediment trace element geochemistry of Lake Coeur d’Alene, Idaho, USA. Part II: Subsurface sediments. Hydrol. Process. 9(1):35-54. Johnson, G.D., D.J. Audet, J.W. Kern, L.J. LeCaptain, M.D. Strickland, D.J. Hoffman, and L.L. McDonald. 1999. Lead exposure in passerines inhabiting lead-contaminated flood-plains in the Coeur d’Alene River Basin, Idaho, USA. Environ. Toxicol. Chem. 18(6): 1190-1194. Kiffney, P., and W.H. Clements. 1993. Bioaccumulation of heavy metals by benthic invertebrates at the Arkansas River, Colorado. Environ. Toxicol. Chem. 12(8):1507-1517. La Point, T., S.M. Melancon, and M.K. Morris. 1984. Relationships among observed metal concentrations, criteria, and benthic community structural responses in 15 streams. J. Water Pollut. Control Fed. 56:1030-1038. Maret, T.R., and D.E. MacCoy. 2002. Fish assemblages and environmental variables associated with hard-rock mining in the Coeur d’Alene River Basin, Idaho. Trans. Am. Fish. Soc. 131(5):865-884. Pain, D.J. 1996. Lead in waterfowl. Pp. 251-264 in Environmental Contaminants in Wild-life: Interpreting Tissue Concentrations, W.N. Beyer, G.H. Heinz, and A.W. Redmon-Norwood, eds. Boca Raton, FL: Lewis Publishers. Ruud, D.F. 1996. A Comparison of the Macroinvertebrate Communities of a Trace Elements Enriched Lake and Uncontaminated Lake in North Idaho: The Effects of Mine Waste Contamination in Coeur d’Alene Lake. M.S. Thesis, Eastern Washington University, Cheney, WA. Santore, R.C., D.M. Di Toro, P.R. Paquin, H.E. Allen, and J.S. Meyer. 2001. Biotic ligand model of the acute toxicity of metals. 2. Application to acute copper toxicity in freshwater fish and Daphnia. Environ. Toxicol. Chem. 20(10):2397-2402.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin Santore, R.C., R. Mathew, P.R. Paquin, and D.M. Di Toro. 2002. Application of a biotic ligand model to predicting zinc toxicity to rainbow trout, fathead minnow, and Daphnia magna. Comp. Biochem. Physiol. C Toxicol. Pharmacol. 133(1-2):271-285. Stratus Consulting. 2000. Report of Injury Assessment and Injury Determination: Coeur d’Alene Basin Natural Resource Damage Assessment. Prepared for U.S. Department of the Interior, Fish and Wildlife Service, U.S. Department of Agriculture, Forest Service and Coeur d’Alene Tribe, by Stratus Consulting Inc., Boulder, CO. September 2000. Suter, G.W. II, B.W. Cornaby, C.T. Hadden, R.N. Hull, M. Stack, and F.A. Zafran. 1995. An approach for balancing health and ecological risks at hazardous waste sites. Risk Anal. 15(2):221-231. Suter, G.W., R.A. Efroymson, B.E. Sample, and D.S. Jones. 2000. Ecological Risk Assessment for Contaminated Sites. Boca Raton, FL: Lewis Publishers. URS Greiner, Inc., and CH2M Hill. 2001a. Final (Revision 2) Remedial Investigation Report, Remedial Investigation Report for the Coeur d’Alene Basin Remedial Investigation/ Feasibility Study. URSG DCN 4162500.6659.05a. Prepared for U.S. Environmental Protection Agency, Region 10, Seattle, WA, by URS Greiner, Inc., Seattle, WA, and CH2M Hill, Bellevue, WA. September 2001. URS Greiner, Inc., and CH2M Hill. 2001b. Final (Revision 2) Remedial Investigation Report, Remedial Investigation Report for the Coeur d’Alene Basin Remedial Investigation/Feasibility Study, Vol. 4. Part 5. CSM Unit 4, Coeur d’Alene Lake. URSG DCN 4162500. 6659.05a. Prepared for U.S. Environmental Protection Agency, Region 10, Seattle, WA, by URS Greiner, Inc., Seattle, WA, and CH2M Hill, Bellevue, WA. September 2001. URS Greiner, Inc., and CH2M Hill. 2001c. Technical Memorandum: Interim Fishery Benchmarks for the Initial Increment of the Remediation in the Coeur d’Alene River Basin (Final). URS DCN 4162400.6779.05.a. Prepared for U.S. Environmental Protection Agency, Region 10, Seattle, WA, by URS Greiner, Inc., Seattle, WA, and CH2M Hill, Bellevue, WA. September 2001. URS Group, Inc., and CH2M Hill. 2004. Coeur d’Alene Basin Environmental Monitoring Plan. Bunker Hill Mining and Metallurgical complex Operable Unit 3. URS DCN 4162500.07190.05.a. Prepared for U.S. Environmental Protection Agency, Region 10, Seattle, WA, by URS Group, Inc., Seattle, WA, and CH2M Hill, Bellevue, WA. March 26, 2004 [online]. Available: http://yosemite.epa.gov/.../fb6a4e3291f2d28388256d140051048b/503bcd6aa1bd60a288256cce00070286/$FILE/Preface.pdf [accessed Jan. 25, 2005]. USGS (U.S. Geological Survey). 2005. NWISWeb Data for the Nation. U.S. Department of the Interior, U.S. Geological Survey [online]. Available: http://waterdata.usgs.gov/nwis [accessed Feb. 18, 2005]. Wesche T.A. 2004. Expert Report. U.S. District Court for the District of Idaho, U.S.A. v. ASARCO Incorporated, et al. No.CV98-0122-N-EJL, Phase II. August 2004. Woodward, D.F. 1995. June-July Field Avoidance and Toxicity Test Activities. Memo to Coeur d’Alene Basin—Natural Resource Damage Assessment Trustees, from Daniel F. Woodward, Project Leader, U.S. Department of the Interior, National Biological Service, Midwest Science Center, Jackson, WY. August 1, 1995. 7 pp. Woodward, D.F., J.A. Hansen, H. Bergman, E. Little, and A.J. DeLonay. 1995. Brown trout avoidance of metals in water characteristic of the Clark Fork River, Montana. Can. J. Fish. Aquat. Sci. 52(9):2013-2017. Woodward, D.F., J.N. Goldstein, A. Farag, and W.G. Brumbaugh. 1997. Cutthroat trout avoidance of metals and conditions characteristic of a mining waste site: Coeur d’Alene River, Idaho. Trans. Am. Fish. Soc. 126(4):699-706.

OCR for page 284
Superfund and Mining Megasites: Lessons from the Coeur d’alene River Basin Woodward, D.F., D.W. Reiser, E.D. Jeanes, A.M. Farag, D. Harper, K.M. Binkley, B. Brumbaugh, E.J. Connor, and C. Hogstrand. 1999. Metals Contamination of the South Fork, Coeur d’Alene River, Idaho: Assessing Factors Reducing Wild Trout Abundance. U.S. Geological Survey, Columbia Environmental Research Center, Jackson, WY; R2 Resources, Redmond, WA; City of Seattle City Light, Seattle, WA; U.S. Geological Survey, Columbia Environmental Research Center, Columbia, MO; and University of Kentucky, Lexington, KY. April 23, 1999.