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San Jose, CA, United States

Muindi T.M.,Haley and Aldrich
Pipelines 2013: Pipelines and Trenchless Construction and Renewals - A Global Perspective - Proceedings of the Pipelines 2013 Conference | Year: 2013

Replacement of aging pipeline infrastructure is requiring construction along alignments that are highly contaminated and subject to costly and stringent regulatory controls. New installations where favorable routing is not available are also subject to similar constraints. Examples of where these installations can be found are: former industrial sites, reclaimed or filled urban lands, and rivers impacted by past industrial activity and navigation. This paper examines some adaptations to the trenchless construction processes that lead to risk minimization, thus enabling installation in these environmentally adverse ground conditions. To illustrate adaptability of trenchless methods, this paper presents a successful case study where pipe installation in highly-contaminated subsurface conditions was accomplished using trenchless methods, namely: horizontal directional drilling (HDD) launched from a former industrial site. © 2013 American Society of Civil Engineers. Source

Triplett Kingston J.L.,Haley and Aldrich | Dahlen P.R.,Arizona State University | Johnson P.C.,Arizona State University
Ground Water Monitoring and Remediation | Year: 2010

In situ thermal-based soil and aquifer remediation technologies (e.g., electrical resistance heating [ERH], conductive heating, and steam-based heating) have undergone rapid development and application in recent years. These thermal technologies offer the promise of more rapid and thorough treatment of nonaqueous phase liquid (NAPL) source zones; however, their field-scale application has not been well documented in the technical literature. A state-of-the-practice review of the application of these technologies was conducted in this study. Available documents from 182 applications were reviewed, which included 87 ERH, 46 steam-based heating, 26 conductive heating, and 23 other heating technology applications conducted between 1988 and 2007. Approximately 90% of the 182 applications were implemented after 1995 and about half since 2000. More specifically, this review identified the geologic settings in which these technologies were applied, chemicals treated, design parameters, operating conditions, and performance metrics. The results of this study are summarized in a table linking this information to five generalized geologic scenarios. Practitioners considering thermal technologies for their site can identify the geologic scenario that most closely resembles their site and then can quickly see which technologies have been applied in that setting, the designs employed, operating conditions, and the performance achieved. © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association. Source

Triplett Kingston J.L.,Haley and Aldrich | Dahlen P.R.,Arizona State University | Johnson P.C.,Arizona State University
Ground Water Monitoring and Remediation | Year: 2012

A recent study assessing the state-of-the-practice of in situ thermal remediation technologies (e.g., electrical resistive heating [ERH], conductive heating, steam-based heating, in situ large-diameter auger soil mixing with steam/hot air injection, and radio-frequency heating) identified 182 applications in the 1988 to 2007 period and summarized the geologic settings in which these technologies were applied, chemicals treated, design parameters, and operating conditions. That study concluded that documentation for less than 8% of those applications contained sufficient data to assess the effect remediation had on groundwater quality. Consequently, post-treatment data were collected at five ERH sites, with emphasis on assessing reductions in dissolved groundwater concentrations and mass discharge (mass flux) to the aquifer. For each site, dissolved groundwater concentrations and hydraulic conductivities were determined across a vertical transect oriented perpendicular to groundwater flow and at the downgradient edge of the treatment zone. Dissolved concentration and mass discharge reductions ranged from about less than 10× to 100×, with post-treatment groundwater concentrations ranging from about 10 1 to 10 4μg/L and mass discharges ranging from about 10 -1 to 10 2 kg/y. The primary factors differentiating sites with greater and lesser dissolved concentration and mass discharge reductions were the adequacy of pre-treatment source zone delineation, the extent to which the treatment zone encompassed the source zone, and the duration of treatment at the design operating temperature. The results suggest that ERH systems are capable of reducing groundwater concentrations to 10 to 100 μg/L levels and lower in some settings, but only if the source zone is adequately delineated and fully encompassed by the treatment system, and the treatment system is operated for a sufficiently long period of time. © 2012, The Author(s). Ground Water Monitoring & Remediation © 2012, National Ground Water Association. Source

Katyal A.K.,Resources and Systems International Inc | Petrisor I.G.,Haley and Aldrich
Environmental Forensics | Year: 2011

Living with floods and managing rather than controlling them is becoming the norm. Integrated flood management (IFM) strategies are needed for holistic sustainable developments in the floodplains. A combination of structural and nonstructural measures (IFM) is the key to manage flooding risks to life and property, reduce susceptibility, and preserve ecological diversity and integrity, natural resources and values of the floodplains. Forensic applications can further help identify sources of contaminations, synthesize missing historic data, determine equitable cost/benefit distributions and motivate IFM adaptation, as well as evaluating the migration/passage of flood transported contamination. This article reviews flood-associated issues and solutions to date, while proposing integrated flood management (IFM) approaches that take advantage of cutting-edge and sustainable scientific techniques (including forensic fingerprinting) and materials. Moreover, the integration within the legal policies and cost-benefits analysis are discussed along with other aspects of proposed IFM. © 2011 Resources and Systems International, Inc. Source

Martus P.,URS Deutschland GmbH | Schaal W.,Haley and Aldrich
Environmental Forensics | Year: 2010

Signature metabolites provide direct geochemical indication that in-situ biodegradation of released organic compounds (e.g., oil and its refined products) is occurring. Experience shows that monitored natural attenuation site conditions are often more complex than in theory and often require a more profound comprehension of the governing natural attenuation processes. Frequently, there is lack of direct proof that contaminant degradation (mainly through biodegradation) is occurring. Advanced tools are emerging that aim to provide answers about whether contaminants of concern are actually (bio)degraded and to the extent. Signature metabolite analysis provides direct proof of mineral oil hydrocarbon biodegradation and is among these advanced tools. Yet, during the previous 15 years, metabolite analysis has only been used sporadically in research projects. The target metabolites consist of aromatic acids such as benzoates and benzylsuccinates and uniquely indicate in-situ biodegradation of individual contaminants of concern. Three case studies have been summarized to share practical experience with signature metabolite analysis for contaminants that include benzene, toluene, ethyl benzene, and xylenes; trimethylbenzenes; and polycyclic aromatic hydrocarbons. The summarized case study involving jet fuel-contamination was the first reported field study in which aromatic acid homologs were formed by microbial metabolism of C4 through C7 benzene. Signature metabolite analysis can be used to improve understanding of natural attenuation processes to close data gaps with respect to the general degradation mechanisms. Direct evidence for biodegradation (e.g., metabolite identity and concentration; microbial identity and quantity; daughter product degradation ratios, stable carbon isotope ratios) facilitates remediation planning and management; provides information useful to scientists and engineers that must determine the mechanisms that produced observed environmental conditions; and provides information for stakeholders involved in environmental cleanup litigation and cost appropriation. © Taylor & Francis Group, LLC. Source

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