A method for determining volatile organic solvents in chalk pore waters (Southern and Eastern England) and its relevance to the evaluation of groundwater contamination

Characterization of chlorinated solvent contamination in limestone using innovative FLUTe® technologies in combination with other methods in a line of evidence approach

“…The extraction technique for the limestone samples was adapted from a technique developed and previously used for solvents in clay till samples by Scheutz et al (2010), Damgaard et al (2013a+b), and Fjordbøge et al (2016). It exploits a combination of the water and matrix porewater miscibility and the efficiency of immiscible solvent (pentane) extractioncombining and refining the methods of Sterling et al (2005) and Lawrence et al (1990), respectively. Three subsamples of each extract were transferred to GC-MS vials.…”

“…A variety of methods are available for core sampling. Sterling et al (2005) used high-resolution subsampling of cores with an analytical method based on quantitative methanol (water miscible) extraction (Hewitt, 1998) for analysis of chlorinated VOCs in rock core matrices (dissolved and sorbed), and Lawrence et al (1990) used water immiscible solvent extractions of chalk core material (crushed in solvent).…”

The relevance of a DNAPL-tracer test conducted at Base Borden, Canada, to solvent groundwater contamination in the UK

“…The same may also be true of the fractured major aquifers where plumes may often be expected to occupy a relatively narrow zone in relation to the scale of the aquifer. Monitoring of the Sawston incident (Lawrence & Foster 1991) failed to fully track the plume between its potential source and impacted supply borehole.…”

“…Contamination is attributed to widespread historical solvent use, deep penetration of DNAPL into aquifers and solvent persistency and mobility in most groundwater environments. Although some notable solvents research has been conducted in the UK (Lawrence et al 1990;Lerner 1993), larger research programmes have been undertaken abroad, particularly in North America. The prompt introduction of groundwater legislation in the US has instigated much groundwater investigation and remediation, and driven associated programmes of research.…”

The legacy of aquifer pollution by industrial chemicals: technical appraisal and policy implications

“…In contrast, the principal British aquifer, the Chalk (with which this paper is principally concerned), has rapid groundwater flow in fissures, large immobile groundwater storage in micropores and low organic carbon content (Table 2). In consequence transport and attenuation of chlorinated solvents in the Chalk is likely to be radically different from that in shallow alluvial aquifers, for which most research on this topic has been carried out (Lawrence & Foster 1987).…”