The management of impacts on aquatic resources at new mine developments in British Columbia
Creators: name: Winsby, Malcolm Blake
Publisher: name: University of British Columbia
Year: 2010

description: This thesis evaluates the analytical methods and review procedures used for assessing • the impacts on aquatic resources from metal mines in British Columbia. The specific objectives are to evaluate the effectiveness of pre-development assessment studies for anticipating eventual impact management problems, to evaluate analytical weaknesses in the pre-development studies; and, to develop recommendations for improving the methods and procedures currently used for impact management planning. To evaluate the effectiveness of pre-development studies, impact management problems were reviewed for fifteen mines. Pre-development reports submitted by the mine proponents before mine production began were then reviewed to determine to what extent the problems had been anticipated. Twenty-four problems were identified amongst eight mines. Pre-development assessments anticipated 18 of the eventual problems. The relative seriousness of the problems varied considerably. The most serious problems were related to the routine discharge of material (cyanide and metals at gold mines) and to a site-runoff problem (the generation of acid in waste rock at one sulphide ore mine). However, the most common problems (46%) were associated with equipment and structural, failures, mainly tailings facilities (i.e. lines, pumps, and dams). The pre-development assessments were generally more effective for identifying problems related to routine discharge sources and to general site runoff than to the more common equipment and structural failures. To evaluate the analytical methods used in the pre-development studies, the following factors were examined: the apparent influence of government guidelines and procedures; the theoretical weaknesses in the methods used; and, the improvements to analytical methods suggested in recent government Terms of Reference (TOR's). In addition, the types of information and methods used in monitoring and follow-up studies were examined for comparison with the pre-development studies. The approaches and methods used in Stage I studies have been strongly influenced by the 1979 "Procedures" prepared by the B.C. Ministry of Energy, Mines and Petroleum Resources. The Procedures recommend a checklist of topics to address but provide poor guidance on how impact analyses are to be used for developing impact management measures. The more recent site-specific TOR's are, in a sense, pre-assessments of potential sources of effect. The TOR's request more detailed information than generally presented in previous reports submitted by mine proponents. The main analytical weaknesses are: the unclear relationship between the management plans and monitoring programs and the specific resources at risk; and, the absence of critical appraisals of impact management measures, in order to develop a fall-back strategy in the event that the chosen measure is found to be inadequate. Recommendations include: the development of an early and explicit description of the linkages expected between a particular mine and important resources; the preparation of alternate or "fall-back" measures that would be implemented in the event that the chosen methods did not work; the preparation by government agencies of the types of information required to develop effective contingency plans; and, the clear separation of information intended to describe important resources from that which is quantitative baseline data to be used during follow-up monitoring and assessments. Opportunities are identified for the mining industry to undertake a stronger role in the development of analytical standards for impact assessment, both to absorb some of the costs of developing assessment procedures and to increase understanding amongst proponents as to the kind of analytical and impact problems that exist.