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

Abstract

The problem of groundwater contamination by the common chlorinated industrial solvents is becoming increasingly apparent in Britain. Pollution is known to have occurred widely as a result of casual or accidental discharge of such chemicals over many decades. Two case histories demonstrate that the combination of solvent physicochemical properties and Chalk hydrogeological characteristics can result in both extensive transport and extreme persistence in this aquifer.Adequately proving the source of groundwater contamination is onerous. Individual pollution problems are equally likely to be the legacy of past industrial activity as the effect of current industrial practice. At least in its most direct sense this renders the 'polluter-pays' principle ineffective. The situation is further complicated by the technical difficulty, excessive cost and inadequate definition of aquifer restoration. Modifications and clarifications to policy are required to provide a more rational basis for the alleviation of this groundwater pollution problem.

Groundwater pollution by chlorinated solvents: the landmark Cambridge Water Company case

“…The behaviour of chlorinated solvents in the Chalk and other UK aquifers has been studied in detail since the mid-1980s (see Rivett et al 1990;Lawrence et al 1992;Lerner 1993). However, at the time of the events described in this paper (the late 1970s and early 1980s), the behaviour was predicted on the basis of their properties, rather than on the results of field investigations.…”

“…187919581960s 197519761970s 19761979198019831984198419861987199119921993 It tends to migrate rapidly downwards, much more rapidly than water in soil or rock of identical permeability. On reaching the water-table, it continues to migrate downwards until it reaches an effectively impermeable bottom to the aquifer.…”

“…The BGS investigations were conducted as a part of a research project studying synthetic organic contaminants in UK aquifers (Lawrence & Foster 1991;Lawrence et al 1992). The investigations included the following: 9 logging and depth sampling of Sawston Mill and other boreholes; 9 drilling ten boreholes, mainly on and adjacent to the ECL site (see Fig.…”

The protection of groundwaters from the effects of waste disposal

“…In connection with the latter, land uses include chemical manufacturing, smelting, heavy engineering, dry cleaning, tanning, military, mining and agriculture (e.g. Lawrence & Foster 1991;Lerner & Tellam 1992;Lloyd 1992;Kershaw & Clews 1993;Fellingham et al 1993).…”

Controls on dense non-aqueous-phase liquid transport in Permo-Triassic sandstones, UK

“…Groundwater supplies face a threat from a wide range of synthetic organic chemicals (Lawrence & Foster 1991). The so-called chlorinated solvents, which are halogenated hydrocarbons, have been produced for more than a century, with the first production taking place in Germany in the late 19th century.…”