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1.
This article examines specific systematic planning steps that can be used for designing and controlling Triad projects. Triad work strategies act to limit decision uncertainty, expedite schedules to meet project milestones, and reduce costs associated with cleanup activities. As a result, the Triad approach is rapidly increasing in popularity. Good project planning has always been seen as the cornerstone of successful Triad projects. However, the specific steps in the systematic planning process have not been extensively published. Demands of Triad projects, which attempt to make maximum use of innovative technologies and sequencing of activities in a learn‐ as‐you‐go framework, put new demands on regulators and project managers alike. Specific activities and relationships are identified to assist project managers with dynamic work strategies and real‐time measurements to support improved decision making. These include: assembly of stakeholders, a core technical team, and key decisions; development and refinement of a site model; use of demonstrations of methods applicability; development of dynamic work strategies and project sequencing; real‐time data management assessment and presentation; and unitized procurement of technologies and services. © 2004 Wiley Periodicals, Inc.  相似文献   

2.
Redevelopment and reuse plans are often based upon an expedited delineation and remediation life cycle, since delayed reuse usually has economic consequences. It has also become increasingly important to utilize sustainable practices to achieve investigation and remediation goals. In this article, the Triad approach is used to expedite the delineation of a source area within a municipal landfill to complete the remedial effort prior to construction of an urban civic center. The Triad approach uses the three elements of systematic project planning, dynamic work strategy, and real‐time measurement to expedite site characterization (Interstate Technology and Regulatory Council, 2003). In this article, the Triad sampling strategy consisted of two phases. The first phase included in situ screening of soil and groundwater using the membrane interface probe (MIP), and the second phase included confirmatory sampling via vertical profiles in the soil and groundwater. This study found that, using the MIP in a dynamic sampling strategy, a critical element of the Triad approach, combined with the proper placement of confirmatory samples, significantly reduced overall project cost and will expedite the site redevelopment. The use of the Triad approach also contributed to the integration of green and sustainable practices into the project. © 2010 Wiley Periodicals, Inc.  相似文献   

3.
The U.S. Navy Public Works Center (PWC) Environmental Department, San Diego, California, is home to the Navy West Coast Site Characterization and Analysis Penetrometer System (SCAPS). SCAPS has been extensively used at several Navy sites since 1995 to provide real‐time, high‐density data sets. The U.S. Environmental Protection Agency's Triad approach provided an ideal framework for optimizing the use of the Navy SCAPS during a volatile organic compound (VOC) source investigation at Installation Restoration Site 1114 at Marine Corps Base Camp Pendleton. All three elements of Triad—systematic planning, dynamic work strategy, and use of real‐time measurement tools—were implemented to manage decision uncertainty and expedite the site management process. The investigation was conducted using the Navy SCAPS, outfitted with a cone penetrometer, membrane interface probe, and a direct sampling ion trap mass spectrometry detector, which allowed for real‐ time collection of over 690 feet of continuous lithologic information and VOC concentration data. These data were used collaboratively with 24‐hour turnaround US EPA 8260B VOC groundwater results from temporary direct‐ push wells to support the conclusion of a limited source area. Implementation of the Triad approach for this investigation provided an expedited high‐density data set and a refined conceptual site model (CSM) in real time that resulted in cost savings estimated at $2.5M and reduction of the site characterization and cleanup schedule by approximately three years. This project demonstrates how the US EPA's Triad approach can be applied to streamline the site characterization and cleanup process while appropriately managing decision uncertainty in support of defensible site decisions. © 2004 Wiley Periodicals, Inc.  相似文献   

4.
The Triad approach was developed primarily to limit decision uncertainty during cleanups at hazardous waste sites. The fundamental principles of the Triad approach include development of a site characterization model and use of emerging technologies, which can provide data at a higher density than could be affordably collected using traditional data collection methodologies, to refine the model in essentially real time. New data formats are used collaboratively with data in traditional formats to iteratively pin down the relative concentration, nature, and extent of contaminants, thus minimizing decision uncertainties. This article examines the potential admissibility as evidence in legal proceedings of data collected by technologies designed to improve the density of information that are commonly used during the course of Triad‐type projects. The article explains that such criteria may vary depending on the purpose for which the evidence is to be used (e.g., as direct evidence to prove site conditions or as support for the testimony of an expert witness) and the court in which the legal proceeding would take place (e.g., federal court or state court). Admissibility in federal courts of data both as direct evidence and as support for expert witness testimony is covered. © 2005 Wiley Periodicals, Inc.  相似文献   

5.
The Triad Approach was field‐tested to determine if characterization objectives could be met for a brownfields property that had been identified as a future elementary school site. The new school is in response to a New Jersey Supreme Court ruling (the Abbott decision) that directed the state of New Jersey to fund school construction in poorer districts to expand physical facilities to relieve overcrowding. The Triad Approach is promoted by the United States Environmental Protection Agency as a process that has the potential to improve the timeliness and efficiency of site characterization, and the New Jersey Department of Environmental Protection (NJDEP) recently issued a policy statement supporting its potential. Aggressive school construction deadlines are contingent on property acquisitions that are relatively faster than the traditional investigatory process. In addition, given the future sensitive population, the investigations must be thorough. This case study is among the first studies to document the use of the Triad Approach for a future school site. The Triad Approach was used to define site conditions for six areas of concern in a two‐month time frame (from the start of the planning process to completed investigation). © 2004 Wiley Periodicals, Inc.  相似文献   

6.
A significant hindrance to reuse of brownfields properties is the risk associated with redevelopment,specifically the uncertainty associated with environmental cleanup. This article explores an approach tomanaging environmental risk through a combination of risk quantification, environmental insurance, and theTriad Approach to site sampling and data interpretation. The expected costs of environmental liabilities areestimated using the Marsh Peer ReviewSM risk quantification process that employs statistical techniques andhighly experienced technical staff. The outputs of the process indicate premiums and attachment points forinsurance products, but they also point to “critical uncertainties” that drive the insurancepremiums. Insurance premiums are often linked to site delineation deficiencies, such as the magnitude ofimpacted soil or the size of a groundwater plume. The Triad Approach is an integrated site characterizationprocess developed by the Environmental Protection Agency that combines systematic planning, dynamic or adaptivefield decision making and field analytical methods (FAMs). The real‐time data produced by FAMsallow for in‐field resolution of uncertainty about sample location, which in turn provides morerepresentative delineation of contaminant distribution. The trade‐off of using slightly less accuratebut substantially lower cost FAMs is an increase in sampling frequency or density, thereby reducing the risk ofincomplete detection or delineation while yielding a “data set” that is more powerful than fewerindividual data points analyzed through traditional methods. Employing the Triad Approach to analyze the“critical uncertainties” identified in the Peer Review Process can impact insurance premiums andallow for better terms of coverage. The combination of using the Triad Approach and environmental insuranceproducts can lead to more predictable and profitable Brownfield transactions. © 2003 Wiley Peridicals,Inc.  相似文献   

7.
Since the early 1990s the U.S. government has been developing and implementing public policies that advance the redevelopment of brownfields, and the recent passage of the Small Business Liability Relief and Brownfields Revitalization Act (SBLRBRA) will significantly advance efforts to integrate environmental contamination mitigation and redevelopment. Experience has demonstrated that successful redevelopment requires the collection, analysis, and interpretation of environmental data in a timely and cost‐effective manner in order to allow developers and lenders to efficiently use cleanup resources, develop response strategies that integrate cleanup with redevelopment, and support meaningful outreach to involved stakeholders. Recent advances in the science and technology of site characterization hold the promise of improved site characterization outcomes while saving time and money. One such advancement, the Triad Approach, combines systematic up‐front planning with the use of a dynamic field investigation process and the generation of real time data to allow in‐field decision making on sample location selection. This article describes an application of the Triad Approach to redevelopment of an urban greenway in Trenton, New Jersey. The Triad Approach, initiated through a partnership between the City of Trenton, New Jersey Department of Environmental Protection, New Jersey Institute of Technology, and the U.S. Environmental Protection Agency, demonstrated that this approach could accelerate the characterization of the 60‐acre, 11‐parcel project area. Environmental issues that were solved using the Triad Approach included the delineation of the extent of historic fill, determination of no further action for several areas of concern, detailed investigation of specific impacted areas and the acquisition of sufficient data to allow the city to make important decisions regarding remediation costs and property acquisition. © 2003 Wiley Periodicals, Inc.  相似文献   

8.
Many individual scientific and technical disciplines contribute to the multidisciplinary field of remediation science and practice. Because of the relative youth of this enterprise, disciplinary interests sometimes compete and conflict with the primary goal of achieving protective, cost‐effective, efficient projects. Convergence of viewpoints toward a more mature, common vision is needed. In addition, cleanup programs are changing under the influence of Brownfields initiatives and the needs of environmental insurance underwriters. Investigations and cleanups increasingly need to be affordable, yet transparent and defensible. Disciplinary goals and terminology need to better reflect real‐world site conditions while being more supportive of project needs. Yet, technical considerations alone will not ensure project success; better integration of human factors into project management is also required. The Triad approach is well placed to catalyze maturation of the remediation field because it emphasizes (1) a central theme of managing decision uncertainty; (2) unambiguous technical communications; (3) shortened project life‐cycles and multidisciplinary interactions that rapidly build professional expertise and provide feedback to test and perfect programmatic and field practices; and (4) concepts from “softer” sciences (such as economics, cognitive psychology, and decision theory) to capture important human factors. Triad pushes the cleanup industry toward an integrated, practical, second‐generation paradigm that can successfully manage the complexities of today's cleanup projects. © 2004 Wiley Periodicals, Inc.  相似文献   

9.
The U.S. Army Corps of Engineers (US ACE) is responsible for conducting the cleanup of radiological contaminated properties as part of the Formerly Utilized Sites Remedial Action Program. One property is the Rattlesnake Creek (RSC) portion of the Ashland sites. The RSC stream sediments are contaminated with thorium‐230, radium‐226, and uranium. The US ACE is closing RSC using protocols contained within the Multi‐Agency Radiation Survey and Site Investigation Manual (MARSSIM). At RSC, the US ACE developed site‐specific derived concentration guideline level (DCGL) cleanup requirements consistent with the MARSSIM guidance. Because of uncertainty about the distribution of contamination within the creek, the US ACE used the Triad approach to collect data and design remedial actions. Systematic planning helped target the areas of concern, develop a conceptual site model, and identify data gaps to be addressed before remediation plans were finalized. Preremediation sampling and analysis plans were designed to be explicitly consistent with final status survey requirements, allowing data sets to support both excavation planning needs and closure requirements in areas where contamination was not encountered above DCGL standards. Judicious use of real‐ time technologies such as X‐ray fluorescence and gamma walkover surveys minimized expensive off‐ site alpha spectrometry analyses, and at the same time provided the ability to respond to unexpected field conditions. © 2004 Wiley Periodicals, Inc.  相似文献   

10.
Better site characterization is critical for cheaper, faster, and more effective cleanup. This fact is especially true as cleanup decisions increasingly include site redevelopment and reuse considerations. However, established attitudes about what constitutes “data quality” create many barriers to exciting new tools capable of achieving better characterization, slowing their dissemination into the mainstream. Traditional approaches to environmental “data quality” rest on simplifying assumptions that are rarely acknowledged by the environmental community. Data quality assessments focus on the quality of the analysis, while seldom asking what impact matrix heterogeneity has had on analytical results. Assessments of data quality typically assume that chemical contaminants are distributed nearly homogeneously throughout environmental matrices and that contaminant‐matrix interactions are well behaved during analysis. Yet, these assumptions seldom hold true for real‐world matrices and contaminants at scales relevant to accurate risk assessment and efficient remedial design. For the site cleanup industry to continue technical advancement, over‐simplified paradigms must give way to next‐generation models that are built on current scientific understanding. If reuse programs such as Brownfields are to thrive, the scientific defensibility of individual projects must be maintained at the same time as characterization and cleanup costs are lowered. The U.S. Environmental Protection Agency (EPA) offers the Triad Approach as an alternative paradigm to foster highly defensible, yet extremely cost‐effective reuse decisions. © 2003 Wiley Periodicals, Inc.  相似文献   

11.
The U.S. Army Corps of Engineers (US ACE) used the Triad approach to expedite site characterization of contaminated soil at the Former Small Arms Evergreen Infiltration Training Range in Fort Lewis, Washington. The characterization was designed to determine if surface soils contain significant concentrations of metals, with the focus on collecting sufficient data for determining appropriate future actions (i.e., risk analysis or soil remediation). A dynamic sampling and analytical strategy based on rapid field‐based analytical methods was created in order to streamline site activities and save resources while increasing confidence in remediation decisions. Concurrent analysis of soil samples during the demonstration of method applicability (DMA) used both field portable X‐ray fluorescence (FPXRF) and laboratory methodologies to establish a correlation between FPXRF and laboratory data. Immediately following the DMA, contaminated soil from the impact berm was delineated by collecting both FPXRF data and fixed laboratory confirmation samples. The combined data set provided analytical results that allowed for revisions to the conceptual site model for the range and directed additional sample collection activities to more clearly determine the extent and distribution of soil contamination. © 2004 Wiley Periodicals, Inc.  相似文献   

12.
This paper establishes that the collection system within the recycling scheme for consumer electronics in the Netherlands has not been entirely successful in convincing consumers to hand in their used appliances by means of dedicated collection routes. Particularly regarding small appliances, consumers are persisting in their habit of discarding their appliances by means of the refuse bag/bin for regular household waste. Therefore, the current collection system has been unable to direct consumer behavior in the desired direction. Consequently, the layout of the current system is reviewed and redesigned in order to tackle this problem. This design effort applies the Triad model (behavioral model) in the analysis stage and the Morphological Chart method (design tool) in the synthesis stage, and results in a concrete proposal for a new system. Finally, the applicability of this design approach beyond the specific circumstances of the case study presented in this paper is discussed. This case represents only one example of the broader, worldwide challenge to design appropriate collection systems to direct consumer behavior in desired directions. It is argued that the approach presented in this paper could be a valuable contribution to research dealing with this challenge.  相似文献   

13.
A new approach to the maintenance of large microbial populations for bioremediation purposes has been developed in which a centrifugal bioreactor is used to immobilize microbial populations at extremely high density. The cells are ordered into a three‐dimensional array through which wastewater or groundwater volumes may be flowed, unimpeded by frits or screens. The process methodology is independent of the type, shape, or viability of the individual cells immobilized and, thus, may be adapted to many different bioremediation needs. The utilization of this new process has been explored for three different types of remediation: the removal of heavy metals from wastewater, the aerobic degradation of methyl‐tert‐butyl ether (MTBE), and the anaerobic reduction of nitrate to nitrogen gas. This article discusses the use of centrifugal bioreactors and their application in remediation. © 2001 John Wiley & Sons, Inc.  相似文献   

14.
Cost‐effective and efficient site remediation and scientifically defensible decisions require site characterizations that are representative of site conditions. The Triad conceptual site model (CSM) is at the center of a continually improving site characterization process that begins during systematic planning and ends after the last data are developed. To gain the full benefit and greatest cost‐effectiveness, the process of CSM refinement should be performed in real time. Thus, the use of collaborative data is critical for evolving and maturing the CSM. In the field, through the use of all available data that are of known quality, a skilled and experienced field team can collect sufficient site information to mature the CSM in a timely manner. To facilitate the planning and execution of such a process, an easily understandable framework is needed to structure data quality that supports scientifically defensible decisions and efficient projects. This article explores such a framework. © 2004 Wiley Periodicals, Inc.  相似文献   

15.
This article describes a design approach that has been developed for bioremediation of chlorinated volatile organic compound–impacted groundwater that is based upon experience gained during the past 17 years. The projects described in the article generally involve large‐scale enhanced anaerobic dechlorination (EAD) and combined aerobic/anaerobic bioremediation techniques. Our design approach is based on three primary objectives: (1) selecting and distributing the proper additives (including bioaugmentation) within the targeted treatment zone; (2) maintaining a neutral pH (and adding alkalinity when needed); and (3) sustaining the desired conditions for a sufficient period of time for the bioremediation process to be fully completed. This design approach can be applied to both anaerobic and aerobic bioremediation systems. Site‐specific conditions of hydraulic permeability, groundwater velocity, contaminant type and concentrations, and regulatory constraints will dictate the best remedial approach and design parameters for in situ bioremediation at each site. The biggest challenges to implementing anaerobic bioremediation processes are generally the selection and delivery of a suitable electron donor and the proper distribution of the donor throughout the targeted treatment zone. For aerobic bioremediation processes, complete distribution of adequate concentrations of a suitable electron acceptor, typically oxygen or oxygen‐yielding compounds such as hydrogen peroxide, is critical. These design approaches were developed based on understanding the biological processes involved and the mechanics of groundwater flow. They have evolved based on actual applications and results from numerous sites. An EAD treatment system, based on our current design approach, typically uses alcohol as a substrate, employs groundwater recirculation to distribute additives, and has an operational period of two to four years. An aerobic in situ treatment system based on our current design approach typically uses pure oxygen or hydrogen peroxide as an electron acceptor, may involve enhancements to groundwater flow for better distribution, and generally has an operational period of one to four years. These design concepts and specific project examples are presented for 17 sites. © 2012 Wiley Periodicals, Inc.  相似文献   

16.
A recent United States Environmental Protection Agency (US EPA) Expert Panel on Dense Nonaqueous Phase Liquid (DNAPL) Source Remediation concluded that the decision‐making process for implementing source depletion is hampered by quantitative uncertainties and that few useful predictive tools are currently available for evaluating the benefits. This article provides a new planning‐level approach to aid the process. Four simple mass balance models were used to provide estimates of the reduction in the remediation time frame (RTF) for a given amount of source depletion: step function, linear decay, first‐order decay, and compound. As a shared framework for assessment, all models use the time required to remediate groundwater concentrations below a particular threshold (e.g., goal concentration or mass discharge rate) as a metric. This value is of interest in terms of providing (1) absolute RTF estimates in years as a function of current mass discharge rate, current source mass, the remediation goal, and the source‐ reduction factor, and (2) relative RTF estimates as a fraction of the remediation time frame for monitored natural attenuation (MNA). Because the latter is a function of the remediation goal and the remaining fraction (RF) of mass following remediation, the relative RTF can be a valuable aid in the decision to proceed with source depletion or to use a long‐term containment or MNA approach. Design curves and examples illustrate the nonlinear relationship between the fraction of mass remaining following source depletion and the reduction in the RTF in the three decay‐based models. For an example case where 70 percent of the mass was removed by source depletion and the remediation goal (Cg/C0) was input as 0.01, the improvement in the RTF (relative to MNA) ranged from a 70 percent reduction (step function model) to a 21 percent reduction (compound model). Because empirical and process knowledge support the appropriateness of decay‐based models, the efficiency of source depletion in reducing the RTF is likely to be low at most sites (i.e., the percentage reduction in RTF will be much lower than the percentage of the mass that is removed by a source‐depletion project). Overall, the anticipated use of this planning model is in guiding the decision‐making process by quantifying the relative relationship between RTF and source depletion using commonly available site data. © 2005 Wiley Periodicals, Inc.  相似文献   

17.
Remediation technologies can sometimes be established, but are not prevalent, for a variety of reasons; however, they can be subject to the forces of change. In some cases, creative economics promotes new uses, but also process improvements can drive new applications and levels of acceptance. This is what is happening with the deployment of horizontal wells for site assessment and remediation. In essence, decreasing costs and a strategic shift, which can be characterized as “greater flexibility,” are two factors that have brought about a resurgence of horizontal well systems. The latter is specifically tied to moving from monolithic single well systems to segmented well systems and this article explains how this is a next‐generation advancement in site assessment and remediation. As one example, nested, discrete horizontal profiling brings additional accuracy to assessment at sites, especially those challenged by access issues and also provides more directed treatment operations with a unique flexibility in dynamic groundwater systems. Also, with horizontal nested well systems, conceptual site models can be significantly enhanced with new perspectives and, depending on the situation, may provide significant economic advantages in deployment. Finally, this technological advancement creates a new paradigm in contrast, or rather as an adjunct, to vertical profiling and high‐resolution site characterization. In fact, it opens up a new strategic approach that can be called high‐resolution contaminant distribution, because flexible horizontal segmented well systems can be used to navigate “up the spine of the plume” providing discretized data sets that illuminate contaminant distribution in new ways.  相似文献   

18.
Development of a multiple lines of evidence (MLOE) framework to evaluate the intrinsic biodegradation potential of 1,4‐dioxane is vital to implementing management strategies at groundwater sites impacted by 1,4‐dioxane. A comprehensive MLOE approach was formed to provide significant evidence of natural degradation of 1,4‐dioxane comingled with tetrahydrofuran (THF) within a large, diffuse plume. State‐of‐the art molecular biological analyses and compound‐specific isotope analysis (CSIA) were employed to support more traditional approaches for data analysis (concentration trend analyses, spatial distribution, temporal changes, geochemical biodegradation attenuation indicators, plume mass estimates, and fate and transport modeling). The molecular analyses demonstrated that microorganisms capable of both metabolic and cometabolic degradation of 1,4‐dioxane were present throughout the groundwater plume, whereas the CSIA data provided supporting evidence of biodegradation. 1,4‐Dioxane biomarkers were present and abundant throughout the 1,4‐dioxane plume, and our biomarkers tracked the plume with reasonable accuracy. Evidence also suggests that THF‐driven cometabolic biodegradation as well as catabolic 1,4‐dioxane biodegradation were active at this site. These data supplemented the traditional lines of evidence approaches, which demonstrated that 1,4‐dioxane attenuation was occurring across the groundwater plume and that nondestructive physical processes alone did not account for the observed 1,4‐dioxane attenuation. This MLOE framework combining new and traditional analyses demonstrates that this site has a significant capacity for intrinsic biodegradation of 1,4‐dioxane. ©2016 Wiley Periodicals, Inc.  相似文献   

19.
A survey of experts in the application of natural attenuation was conducted to better understand how monitored natural attenuation (MNA) is being applied at chlorinated solvent sites. Thirty‐four remediation professionals provided general information for 191 sites where MNA was evaluated, and site‐specific data for 45 chlorinated solvent plumes being remediated by MNA. Respondents indicated that MNA was precluded as a remedy at only 23 percent of all sites where evaluated as a remedial option. Leading factors excluding MNA as a remedial approach were the presence of an expanding plume and an unreasonably long estimated remediation time frame. MNA is being used as the sole remedy at about 30 percent of the sites, and 33 percent are implementing MNA in conjunction with source zone remediation. The remaining sites are implementing MNA with plume remediation (13 percent), source containment (9 percent), or some other strategy (16 percent). © 2004 Wiley Periodicals, Inc.  相似文献   

20.
Remediation of recalcitrant compounds at sites with high concentrations of volatile organic compounds (VOCs) or nonaqueous‐phase liquids (NAPLs) can present significant technical and financial (long‐term) risk for stakeholders. Until recently, however, sustainability has not been included as a significant factor to be considered in the feasibility and risk evaluation for remediation technologies. The authors present a framework for which sustainability can be incorporated into the remediation selection criteria focusing specifically on off‐gas treatment selection for soil vapor extraction (SVE) remediation technology. SVE is generally considered an old and standard approach to in situ remediation of soils at a contaminated site. The focus on off‐gas treatment technology selection in this article allows for more in‐depth analysis of the feasibility evaluation process and how sustainable practices might influence the process. SVE is more commonly employed for recovery of VOCs from soils than other technologies and generally employs granular activated carbon (GAC), catalytic, or thermal oxidation, or an emerging alternative technology known as cryogenic‐compression and condensation combined with regenerative adsorption (C3–Technology). Of particular challenge to the off‐gas treatment selection process is the potential variety of chemical constituents and concentrations changing over time. Guidance is available regarding selection of off‐gas treatment technology (Air Force Center for Environmental Excellence, 1996; U.S. Environmental Protection Agency, 2006). However, there are common shortcomings of off‐gas treatment technology guidance and applications; practitioners have rarely considered sustainability and environmental impact of off‐gas treatment technology selection. This evaluation includes consideration of environmental sustainability in the selection of off‐gas treatment technologies and a region‐specific (Los Angeles, California) cost per pound and time of remediation comparisons between GAC, thermal oxidation, and C3–Technology. © 2008 Wiley Periodicals, Inc.  相似文献   

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