Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Ground Water Quality and Remediation Progress at DoD Sites

Abstract : This protocol report provides guidance and procedures for successfully using regenerated-cellulose dialysis membrane samplers (dialysis samplers). Development of the protocol was funded under project ER-0313 by the Environmental Security Technology Certification Program (ESTCP). The objectives of this protocol report or user s guide are (1) to discuss the principle of operation of membrane diffusion samplers, (2) to present the basic design and steps in construction of dialysis samplers, (3) to discuss the considerations that must be taken into account before deciding to use a dialysis sampler, (4) to present the steps that must be taken in properly deploying, retrieving, and sampling a dialysis sampler, (5) to discuss the interpretation of field results obtained with dialysis samplers compared to other sampling methodologies, and to discuss how results may vary depending on the hydrologic and chemical variation over a well screen or open interval, and (6) to discuss QA/QC samples that should be collected when using dialysis samplers. This report is primarily concerned with the use of dialysis samplers for collection of groundwater samples from wells, but also discusses briefly the use of dialysis samplers for collection of pore water samples from stream or lake sediments. Findings from a number of recent field comparison case studies in which regenerated cellulose dialysis membrane sampler results are compared to other sampling techniques are reviewed. Dialysis samplers were developed to sample ground water for inorganic and organic constituents using a diffusion-type sampler. The dialysis sampler consists of a tube of high-grade regenerated-cellulose dialysis membrane filled with deionized water and placed inside an outer protective layer of polyethylene mesh. Dialysis samplers must be deployed in the screened or open interval of a well where ground water is flowing past the sampler to obtain a valid sample.