Passive treatment systems for the remediation of acid mine drainage at Wheal Jane, Cornwall

In 1992, Knight Piesold was appointed to formulate a long-term treatment strategy for the remediation of acidic metal-rich minewater issuing from the abandoned Wheal Jane mine in Cornwall, UK. The study has investigated both passive and active treatment technologies. As part of the study, a pilot passive-treatment plant was constructed during 1994, comprising three separate systems. Each system contains the same main treatment stages which consist of five aerobic reedbeds, an anaerobic cell and an aerobic rock-filter. Two of the systems also incorporate pretreatment, one in the form of lime dosing and the Ether in the form of an anoxic limestone drain. This paper discusses the theory and design criteria used in the construction of the plant and examines performance data during the period June 1995 to November 1996.