Green And Sustainable Remediation Research Articles

Qualitative and quantitative simulation of best management practices (BMPs) for contaminated megasite remediation using the SiteWise™ tool

Remediation activities, particularly in megasites, may induce substantial secondary environmental impacts that must be addressed for green and sustainable remediation (GSR) practices. Only limited studies are available quantitatively assessing the environmental footprint and environmental benefits of implementing Best Management Practices (BMPs) in megasite remediation. This study used the SiteWise™ tool, a quantitative environmental footprint assessment for scenario simulation and benefit quantification of BMPs, on a contaminated megasite in Hebei Province, China. We observed a considerable environmental footprint and energy from the remediation. Taking the final implementation alternative (Alt 1) as an example, which is characterized by combining multiple remediation techniques, the greenhouse gas (GHG) emissions reached 113,474 t, the energy used was 2,082,841 million metric British thermal units (MMBTU), and other air pollutant emissions (NOx, SOx, and PM10) amounted to 856 t. Further BMP analyses highlighted the benefits of substituting the conventional solidification/stabilization agent with willow woodchip-based biochar, which could reduce GHG emissions by 50,806 t and energy used by 926,648 MMBTU. The overall environmental benefits of implementing all applicable BMPs in the remediation were significant, with a 66.85%, 50.15%, and 56.05% reduction in GHG emissions, energy used, and other air pollutants, respectively. Our study provides insights into quantifying the environmental footprint and exploring emission reduction pathways for contaminated megasite remediation. It also offers a feasible path for quantifying the environmental benefits of BMPs, promoting the development of GSR of contaminated sites.

Remediation of sediments contaminated by harmful heavy metals using aluminum sulfate: Sustainable approach for practical applications

Chemical washing could be suitable for the remediation of marine sediments contaminated with harmful heavy metals. Considering green and sustainable remediation (GSR), the application of aluminum sulfate (AS) is intended to reduce the costs and environmental impacts. We extracted harmful heavy metals from manganese nodules using an ion exchange mechanism that occurs when AS dissociates in water. AS in the range from 2 % to 5 % was used. The remediation efficiencies using 5 % AS were found to be the highest, at 91.8 % for Ni and ≥ 100 % for other harmful heavy metals. The Pearson's coefficient evaluation showed that increasing elapsed time did not significantly affect the extraction of harmful heavy metals. Pollutants in post-processing products may not cause secondary pollutions if solidification/stabilization and additional treatments are used. Our results can serve as fundamental data for the actual remediation processes using AS not only for deep-sea mining tailings but also contaminated marine sediments.

Environmental Footprint Analysis Tools of Electrokinetic Remediation (EKR): A Bibliometric View of The Literature

Electrokinetic remediation (EKR) technology has been applied in both lab and pilot scales to actual size since 1993. Recently, sustainable measures for EKR have been relatively considered a form of minimizing resource use during land restoration. This study aims to identify the environmental footprint assessment tools that arise during the EKR process according to the scale of the application. 284 scientific literature indexed by Scopus and the Web of Science during 2011-2021 was analyzed using the Systematic Literature Review (SLR) method, and the results were visualized using the VOSviewer application. The investigated parameters included the amount of scientific literature, year of publication, topics of scientific literature, authors of literature and their country of origin, names of reputable journals, and a number of citations. Research results from 43 scientific literature studies show that different environmental footprint analyses in EKR have been applied in various parts of the world. Most of environmental footprint assessment tools used by researchers include life cycle assessment (LCA) and green and sustainable remediation (GSR) tools. A recommendation is given to the GSR tools developed by the US EPA because known to have the simplest analytical method compared to other methods.

A Questionnaire Survey on Contaminated Site Regulators’ View of Implementing Green and Sustainable Remediation in China

Government contaminated site regulators, as policy executors and makers, have a profound impact on the development of green and sustainable remediation (GSR), but their cognitive level of GSR has not been well-studied. China has some experience in the management of contaminated sites and has the foundation to promote GSR. This study was conducted in the form of a questionnaire to investigate the understanding of GSR among Chinese site regulators at different levels. The study found that there was still a lot of resistance to promoting GSR in China. Firstly, even though the regulators thought GSR was necessary in China, most of them did not know GSR very well or lacked practical experience. Secondly, existing national and provincial policy standards did not have a good balance between the environmental, social and economic aspects, but gave priority to the environmental factors. Thirdly, the lack of standard and regulatory requirements was the most significant barrier to the implementation of GSR. The results of the survey can provide a reference for China or other developing countries to implement GSR. Practitioners should provide more knowledge and cases for regulators, supplement national policies or improve the provincial and municipal policy system.

Biochar composites: Emerging trends, field successes and sustainability implications

AbstractEngineered biochars are promising candidates in a wide range of environmental applications, including soil fertility improvement, contaminant immobilization, wastewater treatment and in situ carbon sequestration. This review provides a systematic classification of these novel biochar composites and identifies the promising future trends in composite research and application. It is proposed that metals, minerals, layered double hydroxides, carbonaceous nanomaterials and microorganisms enhance the performances of biochars via distinct mechanisms. In this review, four novel trends are identified and assessed critically. Firstly, facile synthesis methods, in particular ball milling and co‐pyrolysis, have emerged as popular composite fabrication strategies that are suitable for large‐scale applications. Secondly, biochar modification with green materials, such as natural clay minerals and microorganisms, align well with the on‐going green and sustainable remediation (GSR) movement. Furthermore, new applications in soil health improvement and climate change mitigation support the realization of United Nation's Sustainable Development Goals (SDGs). Finally, the importance of field studies is getting more attention, since evidence of field success is critically needed before large‐scale applications.

Implementation of a Green and Sustainable Concept to Evaluate Footprint and Optimize Contaminated Site Remediation in China: A Case Study

Abstract In this study, the application mode and evaluation methods of green and sustainable remediation (GSR) were investigated in a soil remediation project. On-site equipment, materials, and ene...

Strengthening social-environmental management at contaminated sites to bolster Green and Sustainable Remediation via a survey

The Green and Sustainable Remediation (GSR) movement demands informed, integrated, and holistic management of contaminated sites. As such, GSR may become increasingly relevant in developing countries such as China, where vast areas of contaminated land require clean-up. Among other efforts, the World Bank together with China's Foreign Economic Cooperation Office is facilitating GSR adoption through the development of a guideline on social-environmental management. However, there are no existing studies that have considered how the established remediation industry perceives its effectiveness in addressing the various social-environmental management aspects, or how certain aspects have rooted. Without this information, it may be difficult to guide social-environmental practice forward, or introduce GSR into developing remediation markets with any precision. Therefore, a questionnaire survey of remediation participators was undertaken with principal component analysis (PCA) applied to the data to help group the various aspects. The PCA extracted two components for environmental management, ascribed to: (1) on-site/local impacts; and, (2) widespread impacts, and three social management components, ascribed to: (1) community inclusion; (2) economic gain; and, (3) health, safety, and welfare. It was found that the aspects the industry are most familiar with historically are generally dealt with more effectively than those that have only recently been introduced by the GSR movement. In particular, bolstering the management of widespread environmental impacts and giving greater regard to the economic gain of remediation, may be beneficial. In developing countries, public engagement is often very limited, necessitating improvement in remediation policy and guidance.

Targeting cleanups towards a more sustainable future.

A tension arises between society's disposition to protect people at risk from environmental pollution, and an aversion towards the potential harmful side-effects associated with cleanup activities. Here we explore how setting different cleanup standards may influence some of the environmental, social, and economic side-effects of remediation, and how they can be quantified for incorporation into cleanup target setting; these include (1) secondary environmental impacts, assessed by life cycle assessment (LCA); (2) fatalities and injuries, assessed by actuarial risk analysis; and (3) the cost effectiveness of stringent cleanup standards, assessed by the incremental cost-effectiveness ratio (ICER). We argue that only by using optimal cleanup standards that integrate quantified remediation side-effects with health risk assessment (HRA) can the green and sustainable remediation (GSR) movement maximize its potential. Together, the combined approaches may provide a more holistic management of risks for a more sustainable future.

Environmental and socio-economic sustainability appraisal of contaminated land remediation strategies: A case study at a mega-site in China

Green and sustainable remediation (GSR) has become a global trend in the contaminated land remediation field. Growing numbers of countries have adopted GSR procedures published in regulatory and/or technical guidance. China is fast becoming one of the largest remediation markets in the world, and is beginning to engage with GSR. Among other efforts, a taskforce is currently developing the first Chinese technical standard on GSR. This paper presents the context positioning and development of a sustainable remediation assessment indicator set for China. This sustainability indicator set was formed based on existing sustainable remediation guidelines and literature. LCA was used to evaluate environmental impacts, and the results combined with social and economic appraisal via MCA. The indicator set was applied to a remediation ‘mega-site’ in China. The results showed that compared to excavation and landfill, an alternative treatment strategy of soil washing, thermal desorption and S/S brought about relatively less waste generation, better worker safety, and preferable local impacts, leading to higher scores in the environmental and social-economic domains. However, the social-economic scores were limited by a lack of public engagement. The results of the case study have shown that the indicator set is valid, with lessons learnt and suggestions for improvement discussed.

Incorporating life cycle assessment with health risk assessment to select the ‘greenest’ cleanup level for Pb contaminated soil

Green and sustainable remediation (GSR) has emerged as one of the most important pioneering directions in the environmental remediation field. The GSR concept calls for maximizing the ‘net environmental benefit (NEB)’ by taking into account not only the environmental benefit, but also the life cycle environmental cost of remediation operations. However, existing literature to date has not examined how cleanup levels may affect the NEB. In this paper, we proposed a framework that combines life cycle assessment with health risk assessment to derive cleanup levels for remediating contaminated land. This method goes beyond the traditional approach, which focuses on acceptable risk levels to site users. It takes into account the number of potential receptors, as well as life cycle secondary environmental impacts, in order to select the ‘greenest’ cleanup level which maximizes the NEB. A case study was conducted using this framework for a school site with Pb contamination. In comparison with the regulatory guidance value of 255 mg/kg applicable at the time of project implementation, the newly selected optimum cleanup level of 800 mg/kg could increase the NEB by 3%, while reducing economic costs by 36%. The study indicated that as the cleanup level became more stringent, the detrimental secondary impacts of remedial operations increased exponentially, whilst the beneficial primary impact tailed off with diminishing returns. It also showed that more stringent criteria would lead to the cleanup of more widespread areas contaminated by diffusive sources rather than point sources. Overall, the study confirmed our hypothesis that an optimum cleanup level exists when considering both environmental benefit and environmental cost, and the ‘greenest’ cleanup level could be quantitatively determined by calculating NEBs with the proposed framework.

Green and sustainable remediation (GSR) evaluation: framework, standards, and tool. A case study in Taiwan.

Taiwan has a large number of poorly managed contaminated sites in need of remediation. This study proposes a framework, a set of standards, and a spreadsheet-based evaluation tool for implementing green and sustainable principles into remediation projects and evaluating the projects from this perspective. We performed a case study to understand how the framework would be applied. For the case study, we used a spreadsheet-based evaluation tool (SEFA) and performed field scale cultivation tests on a site contaminated with total petroleum hydrocarbons (TPHs). The site was divided into two lots: one treated by chemical oxidation and the other by bioremediation. We evaluated five core elements of green and sustainable remediation (GSR): energy, air, water resources, materials and wastes, and land and ecosystem. The proposed evaluation tool and field scale cultivation test were found to efficiently assess the effectiveness of the two remediation alternatives. The framework and related tools proposed herein can potentially be used to support decisions about the remediation of contaminated sites taking into account engineering management, cost effectiveness, and social reconciliation.

Actuarial Risk Analysis to Promote National Contingency Plan (NCP)‐Consistent Remediation

This article provides a case study of how green and sustainable remediation (GSR) concepts (including, but not limited to, worker risk) can be incorporated into the existing National Contingency Plan (NCP)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedy selection framework. The occupational risks of worker fatalities and injuries associated with two site remediation alternatives were calculated and compared. The results demonstrated that the increased worker risks associated with one of the remedy alternatives rendered it inferior based on the NCP “Balancing Criteria” of short‐term effectiveness. This type of approach is implementable at many sites by leveraging readily available information at the remedy selection stage using published methods and data sources. © 2014 Wiley Periodicals, Inc.

Environmental assessment on electrokinetic remediation of multimetal-contaminated site: a case study

In this study, an environmental assessment on an electrokinetic (EK) system for the remediation of a multimetal-contaminated real site was conducted using a green and sustainable remediation (GSR) tool. The entire EK process was classified into major four phases consisting of remedial investigations (RIs), remedial action construction (RAC), remedial action operation (RAO), and long-term monitoring (LTM) for environmental assessment. The environmental footprints, including greenhouse gas (GHG) emissions, total energy used, air emissions of criteria pollutants, such as NOx, SOx, and PM10, and water consumption, were calculated, and the relative contribution in each phase was analyzed in the environmental assessment. In the RAC phase, the relative contribution of the GHG emissions, total energy used, and PM10 emissions were 77.3, 67.6, and 70.4%, respectively, which were higher than those of the other phases because the material consumption and equipment used for system construction were high. In the RAO phase, the relative contributions of water consumption and NOx and SOx emissions were 94.7, 85.2, and 91.0%, respectively, which were higher than those of the other phases, because the water and electricity consumption required for system operation was high. In the RIs and LTM phases, the environmental footprints were negligible because the material and energy consumption was less. In conclusion, the consumable materials and electrical energy consumption might be very important for GSR in the EK remediation process, because the production of consumable materials and electrical energy consumption highly affects the GHG emissions, total energy used, and air emissions such as NOx and SOx.

토양세척 공정의 환경영향 분석 - 이산화탄소 배출량 및 에너지 사용량을 중심으로

총 석유계탄화수소로 오염된 토양을 정화하기 위한 토양세척공정을 부지 내 및 부지 밖 처리로 구분하여 공정 중 발생하는 환경적인 영향을 녹색 및 지속 가능한 정화 평가모델을 사용하여 평가하였다. 각 단계 별 환경부하의 상대적인 기여도를 평가하기 위해 전체 토양세척공정을 부지조성(1단계), 굴착(2단계), 물리적 선별 및 세척(3단계), 폐수처리(4단계)의 주요한 4단계로 구분하였다. 부지 내 처리 시에는 1단계에서 <TEX>$CO_2$</TEX> 배출량과 에너지사용량의 상대적인 기여도가 각각 87.1%와 80.4%였고, 부지 밖 처리시에는 2단계에서 <TEX>$CO_2$</TEX> 배출량과 에너지사용량의 상대적인 기여도가 각각 82.7%와 80.5%였다. 결론적으로 토양세척공정에서 부지 내 처리의 경우 1단계에서의 세척장치 제작을 위한 철, 스테인리스스틸 등 소비성 재료의 사용이, 부지 밖 처리의 경우 2단계에서의 굴착된 오염토의 운송을 위한 연료의 소비가 환경부하에 영향을 끼치는 가장 중요한 요소이다. 본 연구의 결과는 토양세척 공정의 적용 시 녹색 및 지속 가능한 정화의 달성을 위한 유용한 정보가 될 것으로 기대된다. This study evaluated the environmental impacts of a soil washing (SW) process, especially, we compared the on-site and off-site remediation of TPH-contaminated soil using green and sustainable remediation (GSR) tool. To assess relative contribution of each stage on environmental footprints in the entire soil washing process, we classified the process into four major stages: site foundation (stage I), excavation (stage II), separation & washing (stage III), and wastewater treatment (stage IV). In on-site SW process, the relative contribution of <TEX>$CO_2$</TEX> emissions and energy consumption were 87.1% and 80.4%, respectively in stage I, and in off-site SW process, the relative contribution of <TEX>$CO_2$</TEX> emissions and energy consumption were 82.7% and 80.5%, respectively in stage II. In conclusion, the major factor contributing environmental impact in the SW process were consumable materials including steel and stainless steel for washing equipment in on-site treatment and fuel consumption for transportation of soil in off-site treatment.

Factor analysis and structural equation modelling of sustainable behaviour in contaminated land remediation

Contaminated land remediation has traditionally been viewed as sustainable practice because it reduces urban sprawl and mitigates risks to human being and the environment. However, in an emerging green and sustainable remediation (GSR) movement, remediation practitioners have increasingly recognized that remediation operations have their own environmental footprint. The GSR calls for sustainable behaviour in the remediation industry, for which a series of white papers and guidance documents have been published by various government agencies and professional organizations. However, the relationship between the adoption of such sustainable behaviour and its underlying driving forces has not been studied. This study aims to contribute to sustainability science by rendering a better understanding of what drives organizational behaviour in adopting sustainable practices. Factor analysis (FA) and structural equation modelling (SEM) were used to investigate the relationship between sustainable practices and key factors driving these behaviour changes in the remediation field. A conceptual model on sustainability in the environmental remediation industry was developed on the basis of stakeholder and institutional theories. The FA classified sustainability considerations, institutional promoting and impeding forces, and stakeholder's influence. Subsequently the SEM showed that institutional promoting forces had significant positive effects on adopting sustainability measures, and institutional impeding forces had significant negative effects. Stakeholder influences were found to have only marginal direct effect on the adoption of sustainability; however, they exert significant influence on institutional promoting forces, thus rendering high total effect (i.e. direct effect plus indirect effect) on the adoption of sustainability. This study suggests that sustainable remediation represents an advanced sustainable practice, which may only be fully endorsed by both internal and external stakeholders after its regulatory, normative and cognitive components are institutionalized.

Effectiveness of Capture Zones Generated by Intermittent Pumping of a PV‐Powered Pump‐and‐Treat System Without Energy Storage

AbstractA common technology to remediate and/or contain contaminated groundwater is pump‐and‐treat remediation (P&amp;T). Traditionally, P&amp;T systems have been designed to operate continuously to achieve steady‐state capture zones, for which large amounts of energy are required. Green and sustainable remediation (GSR) is emerging as a viable method to minimize the adverse effects of remediation on the environment. One of the challenges associated with photovoltaic‐ (PV‐) powered P&amp;T systems is the assessment of their performance given the intermittent nature of the power availability. This article characterizes the hydraulic containment effectiveness of a PV‐powered P&amp;T system without energy storage using data collected at two different remediation sites, a Dry‐Cleaning Environmental Response Trust Fund site in Rolla, Missouri, and the Former Nebraska Ordnance Plant near Mead, Nebraska. Additionally, a method to estimate the effectiveness of the hydraulic containment as a function of the total volume of groundwater expected to be extracted is being proposed. Two transient and a continuously pumped capture zones were modeled using Visual MODFLOW® 2012.1 along with MODPATH and compared. The study shows that smaller capture zones will be generated from intermittent pumping when compared to continuous pumping. © 2013 Wiley Periodicals, Inc.

A Case Study on the Evaluation and Implementation of Green and Sustainable Remediation Principles and Practices During a RCRA Corrective Action Cleanup

Green and Sustainable Remediation (GSR) principles and practices were incorporated into various phases of the remediation life cycle during a Resource Conservation and Recovery Act (RCRA) Corrective Action cleanup. GSR best management practices (BMPs) were identified and employed to the extent possible during the investigation, remedy evaluation, and remedy implementation phases of the cleanup. As part of the remedy evaluation phase, potential remedial alternatives were evaluated against GSR principles and practices to support the selection of a preferred remedial alternative. This included the identification of inherent GSR similarities within the five existing RCRA balancing criteria and the development of a sixth new balancing criterion. The sixth criterion consisted of five relevant GSR categories, including consumption of resources and materials, CO2 emissions, waste minimization and reuse, community benefit, and corporate image and corporate sustainability. Because of the lack of consensus, the constantly evolving nature, and limited guidance associated with GSR, various GSR‐related uncertainties and barriers were encountered. These uncertainties and barriers primarily related to the development of a GSR evaluation approach; contractual mechanisms; worker routines; regulatory agency support; and facility benefits, incentives, and recognition. In an effort to overcome some of these uncertainties and barriers, professional judgment was used to support various decision‐making processes. The GSR evaluation and implementation approaches considered are discussed in this case study as well as the various uncertainties and barriers encountered. In general, this case study provides a successful demonstration of GSR, given guidance limitations, facility permit constraints, complexities associated with site‐specific conditions, and a situation where the most feasible options were not considered the most green and sustainable (primarily because of their energy‐intensive nature, resource consumption, or waste generation).