Larry W. Canter

Cumulative impacts are not properly addressed in environmental assessments

Abstract Environmental assessments (EAs) refer to preliminary studies conducted within the environmental impact assessment (EIA) process in the United States; such studies are used to determine the significance of anticipated impacts of proposed actions. If significant impacts are identified, detailed studies leading to the preparation of environmental impact statements (EISs) are necessary. If no significant impacts are expected, findings of no significant impacts (FONSIs) are prepared and the EIA process is completed. Cumulative impacts (CIs) should be considered, along with direct and indirect impacts, in the significance determination documented within an EA. However, CIs may not receive detailed attention due to either the absence of specific requirements or uncertainty as to what to address. This study included a systematic review of CI considerations in 30 EAs prepared on a variety of project types in the United States. In general, it was determined that CIs are neither normally mentioned nor thoroughly addressed; in fact, only 14 EAs even mentioned the term. When CIs were mentioned, they were typically addressed in a qualitative manner without clear delineations of spatial and temporal study boundaries and utilized guidelines or methodologies. Therefore, if EAs are to continue to be decision documents for determining if EISs need to be prepared, significance determinations for CIs must be more systematically addressed and documented. Such documentation could refer to the consideration of CIs and the determination that they are not significant; in contrast; for some EAs the topic of CIs may be the determining issue in decisions to prepare EISs.

State of practice of cumulative effects assessment and management: the good, the bad and the ugly

The historical, current and future international practice of cumulative effects assessment and management (CEAM) is addressed. The ‘context’ of CEAM is explained and challenges from scientific and policy issues and numerous uncertainties are described. A six-step generic process for carrying out CEAM is provided. Opportunities for mitigation and management are highlighted, with emphasis given to ‘collaboration’ as a foundational element for dealing with cumulative effects. This state-of-practice review concludes by noting six ‘ugly lessons’ which result from lack of appropriate attention, eight ‘bad lessons’ which reflect practices that need improvement, and 12 ‘good lessons’ which can be used to articulate good practice principles related to CEAM. In many situations some modification of EIA methods and tools may be necessary. In summary, the practice of CEAM is growing out of its infancy. As experience is accrued, it is anticipated that good practice principles will be further articulated and utilized on an international basis.

Questionnaire checklist for cumulative impacts

Abstract Cumulative impact considerations have been required since 1979 in the environmental impact assessment (EIA) process in the United States. Incorporation of these considerations has been minimal due to confusion over appropriate spatial and temporal boundaries in impact studies, lack of emphasis by project proponents and government agencies, and the absence of structured methodologies. The study described herein was conducted to delineate the types of cumulative impact methods being used in scientific studies and/or environmental impact statements (EISs) and to couple this information with existing EIA methodologies to delineate a generic methodology that could provide a framework for cumulative impact identification and assessment. Eight scientific studies were reviewed, and the utilized methods included five interaction matrices and/or composite indices, two geographic information systems, and one simple checklist. Five EISs were also reviewed relative to how cumulative impacts were addressed and the methodologies utilized. The five EISs included oil and gas leasing and development in New Mexico, a housing/urban development project in McKinney, Texas, a program to install and operate terminal Doppler weather radar facilities at airport locations across the United States, a reservoir project in the Rogue River Basin in Oregon, and a surface lignite mine in Titus County, Texas. All five EISs addressed cumulative impacts to some extent — a simple checklist methodology was used for each, although the checklist items differed from study to study. Based on these findings, and considering extant EIA methodologies, a structured questionnaire checklist is proposed for usage in scoping cumulative impacts, addressing detailed impact issues and summarizing the results of cumulative impact considerations in an impact study. The items in the proposed checklist will not all be applicable to all projects and impact studies. However, usage of this approach would provide a consistent beginning for systematically addressing cumulative impacts.

Impact significance determination—Basic considerations and a sequenced approach

Abstract Determination of the significance of anticipated impacts of proposed projects is a key component in the overall environmental impact assessment (EIA) process. Definitions of significance and/or significant impacts are now included in the EIA guidelines or regulations of many countries and international organizations. Where possible in an EIA study, it is desirable to identify and/or establish the significance determination criteria prior to actual study conduction. This paper summarizes some findings of a survey of such definitions resulting from American, European, and other international experiences; both generic definitions and substantive area definitions are highlighted. Traditional perspectives on significance determination have involved institutional (or governmental or regulatory), technical (or professional substantive area), and public interest considerations. A sequenced approach for impact significance determination is described, with this approach organized around ten groups of issues or questions. Examples of such issues include project type/size, project locations in areas with protected or critical resources, and environmental stresses resulting from waste residuals from the project. Examples of significance criteria pertinent to the issues are presented through the paper. Finally, the uses of significance criteria can be noted; included in such uses are: (1) determining if an environmental impact statement (EIS) will be required, or if an environmental assessment/finding of no significant impact (EA/FONSI) will surface; (2) identifying the impacts that should be mitigated; (3) planning a baseline and/or post-EIS environmental monitoring program; and (4) documenting the interpretive rationale used in the conduction of the environmental impact study.

Documentation of cumulative impacts in environmental impact statements

Abstract The National Environmental Policy Act (NEPA) of 1969 and the Council on Environmental Quality (CEQ) regulations in the United States require federal agencies to apply an environmental impact assessment (EIA) in decision-making related to their actions. One aspect requires an examination of direct, indirect and cumulative impacts (CIs). Historically, cumulative impact assessment (CIA) has been given limited attention in EIA and resultant environmental impact statements (EISs), not because of its lack of importance, but owing to limitations in methodologies and procedures, including documentation consistency. The objectives of this study were to identify deficiencies in the documentation of CIs and CIA in EISs and to formulate appropriate recommendations (potential solutions) related to such deficiencies. The study involved the systematic review of 33 EISs (11 each from the U.S. Department of Agriculture: Forest Service, the U.S. Army Corps of Engineers, and the U.S. Department of Transportation: Federal Highway Administration). The results indicate that improvements have been made in documentation practices since 1990; however, inconsistencies and inadequacies still exist. Therefore, the following recommendations were developed: (1) CIs should be reported in a separate part of the “Environmental Consequences” section, and they should be addressed for each pertinent environmental resource; (2) a summary of CIs should be included; (3) any CIs considered not significant should be mentioned plus the reason(s) for their non-significance; (4) spatial and temporal boundaries addressed within the CIA process should be defined for pertinent environmental resources; and (5) utilized guidelines and methodologies should be described.

Prioritization of ground water contaminants and sources

The objective of this research was to identify chemical, physical, bacteriological, and viral contaminants, and their sources, which present the greatest health threat in public ground water supplies in the USA; and to classify (prioritize) such contaminants and relative to their health concerns. The developed contaminant prioritization methodology was based on frequency of occurrence and adverse health effects. Adverse health effects were based on carcinogenic potency, toxicity, hazardous chemical priorities and drinking water standards. Application of the methodology for wellhead protection areas, (WHPAs) revealed that approximately 200 different contaminants have been detected in the nations public ground water supplies. The seven chemical constituents with the highest priority were arsenic, chromium, cadmium, carbon tetrachloride, chloroform, 1, 1-dichloroethylene, and ethylene dibromide. Other contaminants of concern were trichloroethylene, nitrates, barium, 1,1,1-trichloroethane, benzene, tetrachloroethylene, selenium, lead, toluene, mercury, gross alpha radiation, methylene chloride, coliform bacteria, metolachlor, metribuzin, 1, 1, 2, 2-tetrachloroethane, dibromochloroethane, simazine, radium-266, and toxaphene. The contaminant source prioritization methodology was also based on frequency of occurrence. Over 30 categories of sources were evaluated, with the eight with highest priority including agricultural activities, hazardous waste sites, landfills, industrial operations, septic tank systems, oil and gas field activities, urban land use, and underground storage tanks.

NEPA Effectiveness — A survey of academics

Abstract The National Environmental Policy Act (NEPA) went into effect in the United States on January 1, 1970, just over 25 years ago. In light of this milestone, a survey of academics on the effectiveness of NEPA has been conducted regarding the preparation of environmental assessments (EAs) or environmental impact statements (EISs). This paper summarizes the results of a survey of 31 academics in 12 disciplines from 21 states; the majority of which have over 20 years of experience in teaching, research and/or practice of the NEPA process. Several strengths of NEPA were identified, most importantly that NEPA encourages agencies and decision makers: (1) to acknowledge potential environmental consequences to the public, thus opening up the decision process; and (2) to think about environmental consequences before resources are committed. Surveyed participants also prioritized needs for improvement; the five most important were: (1) post-EIS follow-up in monitoring, implementation of mitigation measures, ecosystem management, and environmental auditing; (2) methodological approaches for addressing cumulative impacts and reductions in institutional barriers to analysis of cumulative impacts; (3) training of federal personnel implementing NEPA; (4) earlier considerations of NEPA in project planning and decision making; and (5) the integrated consideration of biophysical and social/economic sciences, along with risk assessment, in NEPA. While this survey was focused on the NEPA process in the United States, the identified issues have implications for the worldwide practice of environmental impact assessment. Finally, recommendations are described that are primarily associated with guidance, possible modifications in the NEPA process and follow-on training.

Adaptive management with integrated decision making: an emerging tool for cumulative effects management

Adaptive management (AM) is being used as a follow-up tool within EIA/CEAM. Such uses include reducing cumulative effects uncertainties, and informing decision making on practices to minimize the incremental effects of proposed actions and the management of regional cumulative effects resulting from multiple contributors. Based upon a review of fundamental concepts, practices and case studies, the following key lessons have been identified: (1) AM can be a useful tool for coping with uncertainty in CEAM, improving the knowledge base and enhancing the effectiveness of cumulative effects mitigation and management at the project and regional level respectively; (2) decision flowcharts can facilitate the learning and necessary adaptations associated with AM programs, and such flowcharts should be both understandable and integrative in relation to developing an holistic perspective on management choices and their environmental implications; and (3) there is a primary need for comparative case studies illustrating how AM has been incorporated in NEPA compliance documents which address cumulative effects management.

Planning and operational guidelines for mitigation banking for wetland impacts

Abstract Mitigation of wetland losses due to development activities is an important public policy issue in the United States. Such mitigation could include avoidance, minimization, rectification, reduction, or compensation. If the first four measures are not feasible, then compensation is required. Wetland mitigation banking is one type of compensation; it refers to a process where a developer purchases a land area and restores, enhances, or creates plant or animal wetland habitat prior to any development activities. These improvements are quantified and credit is placed in a bank; at a later date, when unavoidable impacts due to the development occur, the credit can be withdrawn. Due to the relative infancy of mitigation banking, a questionnaire survey of 19 existing and 20 proposed banks in the United States has been conducted to determine the state-of-practice relative to eight identified planning and/or operational issues. The issues included bank goals, site selection, bank operator, policies for credit (habitat units) establishment and usage, preferred wetland development options, criteria for bank usage, long-term management plans, and construction and maintenance requirements. The survey results were then used to formulate 10 guidelines for planning and operating banks; they are: (1) the goal of resource agencies and developers should be to provide an efficient and effective means of providing mitigation while at the same time decreasing the time involved in the permitting process; (2) site selection and construction should take place prior to development project impacts; (3) the bank operator should be the developer and/or a combination of resource/regulatory agencies whose responsibilities are to carry out administrative and technical duties and develop long-term management plans; (4) establishment of bank credits/debits should be based on recognized habitat methods; (5) the preferred order of wetland development option usage are restoration, enhancement, construction, and preservation; (6) development projects eligible for bank use must have proven to the applicable regulatory agencies that the sequential mitigation hierarchy is not possible and the project has no alternatives; (7) earmarked accounts, trust funds, or long-term interest bearing accounts should be used to guarantee funds for long-term management; (8) during bank construction, best management practices for erosion and fugitive dust control should be implemented to protect adjacent ecosystems; (9) postmonitoring should be conducted annually for at least 10 years to determine the success or failure of a bank site and to provide information for future maintenance efforts; and (10) bank account statements should be sent semiannually to bank users and after each transaction to signess of any Memorandum of Understanding/Agreement for their response and approval.

Contamination of public ground water supplies by Superfund sites

Multiple sources of contamination can affect ground water supplies, including municipal landfills, industrial operations, leaking underground storage tanks, septic tank systems, and prioritized uncontrolled hazardous waste sites known as “Superfund” sites. A review of Superfund Records of Decision (RODs) in the United States was conducted in this study to obtain information concerning incidents of public ground water supply contamination. Approximately 450 separate RODs or their abstracts were reviewed, and 49 cases with municipal water well contamination were identified. In addition to the 49 pertinent cases, a significant number of RODs listed contaminated ground water as a potential threat to local public water supply wells. The 49 cases were geographically distributed in 21 states throughout the United States. The main source of contamination was industrial operations and other activities associated with industries. In 34 of 49 relevant Superfund cases, industry and related activities were identified ...