Potential effects and impacts of a coal spill on sensitive aquatic habitat: a weight-of-evidence sediment quality assessment

Abstract

Abstract On 11 January 2014, a Canadian Pacific Railway train derailed on the Canadian National Railway Company's Yale Subdivision, Mile 122.7, in Burnaby, British Columbia, Canada. This derailment resulted in the partial release of metallurgical coal from three rail cars into, and adjacent to, Silver Creek. Following the derailment and subsequent spill, a comprehensive coal recovery program was implemented. As part of the program, coal deposits were removed from the Silver Creek mainstem in the right-of-way during the stabilization work. A total of approximately 143 tonnes of mixed coal, organic and mineral fines were removed during this program. Subsequently, using a weight-of-evidence sediment quality triad approach, a two-year Aquatic Impact Assessment was conducted to evaluate whether the remaining residual coal in Silver Creek and Burnaby Lake presented the potential for impact to the aquatic environment. Lines-of-evidence (LOEs) were evaluated, including sediment chemistry, sediment toxicity, bioaccumulation potential and coal content. The majority of the data from exposed sampling locations indicated that there was low potential for impact, based on the assessed LOEs. Hence, given the overall low potential for residual impacts from the coal deposits in the Silver Creek–Burnaby Lake ecosystem, no further clean up or monitoring was recommended.