Like other industrialized nations, groundwater supplies beneath many industrial sites in Sweden are contaminated with chlorinated solvents. Compared to countries in North America and other parts of Europe, however, chlorinated solvent impacts in Sweden have not attracted much attention until recently. In 2005, the Swedish Environmental Protection Agency (Naturvardsverket) recognized the need for national guidance on chlorinated solvent remediation. To meet this need, they commissioned a project for the development of a Technical Manual for Screening and Selecting Technologies for Remediation of Chlorinated Solvents in Soil and Groundwater and selected an international team of experts, consisting of SWECO VIAK (Sweden), Geosyntec Consultants (USA and Canada), and COWI A/S (Denmark) to write the Manual.
Geosyntec's Scope of Services
The Manual introduces stakeholders, authorities, consultants, and contractors to chlorinated solvent remediation, and presents a systematic protocol for evaluating and selecting one or more remediation technologies for a given site. This protocol, modeled after U.S. Environmental Protection Agency guidance on conducting feasibility studies, consists of the following five steps: (i) development of remedial action objectives (i.e., identify the purpose of remediation); (ii) development of general response actions (e.g., institutional controls, physical containment, or mass removal); (iii) preliminary screening to identify a broad list of feasible and appropriate remedial alternatives; (iv) detailed technology evaluation to identify a focused short list of remedial alternatives; and (v) assembly and detailed evaluation of site-specific remedial alternatives. An example case study is presented to illustrate application of this protocol for a chlorinated solvent site in Sweden.
The Manual also includes detailed technical fact sheets for a variety of chlorinated solvent remediation technologies, including excavation, pump-and-treat, air sparging/soil vapor extraction, multi-phase extraction, in situ flushing, in situ thermal remediation, in situ bioremediation, in situ chemical oxidation, in situ metal-catalyzed reduction, and phytoremediation. Each fact sheet includes information regarding technology treatment mechanisms, applicability to varying geologic terrains, applicability to plumes and source zones, design criteria, costs, and links to key guidance documents that are available on the Internet. The Manual was finalized in the Spring of 2007, and is available on the Naturvårdsverket website (http://www.internat. naturvardsverket.se/).
This first-of-its-kind guidance manual that Geosyntec co-authored is an important step in Sweden's ability to manage and remediate its industrial sites contaminated with chlorinated solvents. Geosyntec's world-class expertise and dedication to the project ensured successful completion, despite the challenge that portions of the initial draft of the document were written in Danish, Swedish, and English.