398 research outputs found

    Murdock, Nebraska, Groundwater Flow and Transport Modeling in Support of Long-Term Monitoring

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    Fall 2002 Assignments: • Update all models to MODFLOW-2000 • Re-calibrate original Murdock steady-state groundwater flow model to November 25, 1998 observed water levels (Phase 1 hydrology) • Determine time when climatological/hydrolic regime changed in eastern Nebraska. Groundwater levels observed in 2002 are significantly lower than all values observed previously (1997-1999). Palmer Hydrologic Drought Index. • Determine appropriate groundwater level data for calibration of new (Phase 2) groundwater flow model representing current hydrologic regime (avg. of 2002 observations) • Re-evaluate/recalculate initial CCl4 concentrations for MT3D-99 solute transport model calibration – 1996/97 concentration data. Too much CCl4 mass in eastern portions of original transport model • Re-calibrate Murdock MT3D-99 solute transport model to November 1999 observed concentrations using revised initial 1996/97 concentrations • Include historical average concentrations at S2 as a constant concentration in transport model • With re-calibrated solute transport model simulate CCl4 dissolved phase transport from December 12, 1996 to December 31, 1999 with Phase 1 goundwater flow model • Simulate CCl4 solute transport from January 1, 2000 to December 12, 2012 with Phase 2 groundwater flow model and CCl4 initial conditions set at December 31, 1999 simulated values (i.e., Phase 1 model ending concentrations) • Plot simulated CCl4 concentration time series for all trigger action wells, and non-trigger action wells monitored during 2002 for all layers inclusive in each well screened interval • Set the trigger action level to the maximum simulated screen interval concentration for each trigger action wel

    Scientific and Legal Perspectives on Science Generated for Regulatory Activities

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    This article originated from a conference that asked “Should scientific work conducted for purposes of advocacy before regulatory agencies or courts be judged by the same standards as science conducted for other purposes?” In the article, which focuses on the regulatory advocacy context, we argue that it can be and should be. First, we describe a set of standards and practices currently being used to judge the quality of scientific research and testing and explain how these standards and practices assist in judging the quality of research and testing regardless of why the work was conducted. These standards and practices include the federal Information Quality Act, federal Good Laboratory Practice standards, peer review, disclosure of funding sources, and transparency in research policies. The more that scientific information meets these standards and practices, the more likely it is to be of high quality, reliable, reproducible, and credible. We then explore legal issues that may be implicated in any effort to create special rules for science conducted specifically for a regulatory proceeding. Federal administrative law does not provide a basis for treating information in a given proceeding differently depending on its source or the reason for which it was generated. To the contrary, this law positively assures that interested persons have the right to offer their technical expertise toward the solution of regulatory problems. Any proposal to subject scientific information generated for the purpose of a regulatory proceeding to more demanding standards than other scientific information considered in that proceeding would clash with this law and would face significant administrative complexities. In a closely related example, the U.S. Environmental Protection Agency considered but abandoned a program to implement standards aimed at “external” information

    Environmental Systems and Local Actors: Decentralizing Environmental Policy in Uganda

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    In Uganda, environmental and natural resource management is decentralized and has been the responsibility of local districts since 1996. This environmental management arrangement was part of a broader decentralization process and was intended to increase local ownership and improve environmental policy; however, its implementation has encountered several major challenges over the last decade. This article reviews some of the key structural problems facing decentralized environmental policy in this central African country and examines these issues within the wider framework of political decentralization. Tensions have arisen between technical staff and politicians, between various levels of governance, and between environmental and other policy domains. This review offers a critical reflection on the perspectives and limitations of decentralized environmental governance in Uganda. Our conclusions focus on the need to balance administrative staff and local politicians, the mainstreaming of local environmental policy, and the role of international donors

    Effectiveness of waste minimisation projects in reducing water demand by UK industry

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    There is growing interest in managing water demand in the UK. A series of waste minimization clubs have been set up within the country and this paper identifies the effectiveness of these clubs in reducing the demand for water within industry. Membership of these clubs is voluntary and the only incentive for industry to reduce water consumption, and consequently the production of effluent, is the almost immediate financial saving made by the company, often achieved by accounting for the water consumption and loss within site from the point of input from the water supplier to output in the form of effluent. On average, companies are able to reduce water consumption by up to 30 percent. If the entire industrial sector within the UK were to achieve this degree of savings, it is possible that approximately 1300Ml/d could be saved

    Environmental impact assessments of the Three Gorges Project in China: issues and interventions

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    The paper takes China's authoritative Environmental Impact Statement for the Yangzi (Yangtze) Three Gorges Project (TGP) in 1992 as a benchmark against which to evaluate emerging major environmental outcomes since the initial impoundment of the Three Gorges reservoir in 2003. The paper particularly examines five crucial environmental aspects and associated causal factors. The five domains include human resettlement and the carrying capacity of local environments (especially land), water quality, reservoir sedimentation and downstream riverbed erosion, soil erosion, and seismic activity and geological hazards. Lessons from the environmental impact assessments of the TGP are: (1) hydro project planning needs to take place at a broader scale, and a strategic environmental assessment at a broader scale is necessary in advance of individual environmental impact assessments; (2) national policy and planning adjustments need to react quickly to the impact changes of large projects; (3) long-term environmental monitoring systems and joint operations with other large projects in the upstream areas of a river basin should be established, and the cross-impacts of climate change on projects and possible impacts of projects on regional or local climate considered. © 2013 Elsevier B.V.Xibao Xu, Yan Tan, Guishan Yan

    Integrating Human Health into Environmental Impact Assessment: An Unrealized Opportunity for Environmental Health and Justice

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    The National Environmental Policy Act and related state laws require many public agencies to analyze and disclose potentially significant environmental effects of agency actions, including effects on human health. In this paper we review the purpose and procedures of environmental impact assessment (EIA), existing regulatory requirements for health effects analysis, and potential barriers to and opportunities for improving integration of human health concerns within the EIA process. We use statutes, regulations, guidelines, court opinions, and empirical research on EIA along with recent case examples of integrated health impact assessment (HIA)/EIA at both the state and federal level. We extract lessons and recommendations for integrated HIA/EIA practice from both existing practices as well as case studies. The case studies demonstrate the adequacy, scope, and power of existing statutory requirements for health analysis within EIA. The following support the success of integrated HIA/EIA: a proponent recognizing EIA as an available regulatory strategy for public health; the openness of the agency conducting the EIA; involvement of public health institutions; and complementary objectives among community stakeholders and health practitioners. We recommend greater collaboration among institutions responsible for EIA, public health institutions, and affected stakeholders along with guidance, resources, and training for integrated HIA/EIA practice

    Ecosystem services of temporary streams differ between wet and dry phases in regions with contrasting climates and economies

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    1. Temporary streams are dynamic ecosystems in which mosaics of flowing, ponded and dry habitats support high biodiversity of both aquatic and terrestrial species. Species interact within habitats to perform or facilitate processes that vary in response to changing habitat availability. A natural capital approach recognizes that, through such processes, the ‘natural assets’ of all ecosystems deliver services that benefit people. 2. The ecosystem services of temporary streams remain largely unexplored, in particular those provided during ponded and dry phases. In addition, recent characterizations have focused on dryland systems, and it remains unclear how service provision varies among different climatic regions, or between developed and developing economies. 3. We use evidence from interdisciplinary literature to examine the ecosystem services delivered by temporary streams, including the regulating, provisioning and cultural services provided across the continuum from flowing to dry conditions. We focus on service provision during dry phases and wet–dry transitions, across regions with contrasting climates and economic development. 4. Provision of individual services in temporary streams may be reduced, enhanced or changed by surface water loss. Services enhanced by dry phases include provision of higher‐quality subsurface drinking water and unique opportunities for recreation. Shifts between dry and wet phases enable groundwater recharge that mitigates water scarcity, and grant dry‐phase access to sediments deposited during flowing phases. However, the accessibility and thus perceived value of these and other services varies considerably among regions. In addition, accessing provisioning services requires careful management to promote sustainable resource use and avoid ecological degradation. 5. We highlight the need for environmental managers to recognize temporary streams as aquatic–terrestrial ecosystems, and to take actions promoting their diversity within functional socio‐ecological systems that deliver unique service bundles characterized by variability and differing availability in space and time

    Brownfields to green fields: Realising wider benefits from practical contaminant phytomanagement strategies

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