Pierre River Mine Project

WATER ERCB SIRS 46 – 79
Section 7.1
70a How does the above statement meet Shell’s commitment to use Best Available
Environmental Practices?
Response 70a Shell uses best industry practices in its activities, including the preparation of the
Pierre River Mine and Jackpine Mine Expansion environmental assessment. The
quoted statement demonstrates that Shell has used the most current information
available, and the advice of experts knowledgeable about water quality issues in
the Athabasca area, which Shell believes represents best industry practices.
Question No. 71
Request Volume 4A, Section 6.1.4, Page 6-361.
Shell states, “Project releases will not contribute to BTEX concentrations.” Shell
further states, “Gypsum and thickeners may be used in creating NST” and
“Water and sediment quality changes due to the Project effects are not classified
in this section.”
71a Describe the potential for BTEX compounds in end products due to the
breakdown of the solvent.
Response 71a The solvent is paraffinic and does not contain substantial amounts of toluene,
ethyl benzene or xylene. The solvent contains only a small amount of benzene,
the impact of which has been included in the environmental assessment. The
compounds in the solvent (primarily pentanes and hexanes) are not expected to
decompose into BTEX compounds.
Request 71b What are the environmental impacts of asphaltene disposal in the tailings pond?
Response 71b The addition of asphaltenes to a tailings pond is unlikely to degrade the water
quality of the tailings pond and is supported by current operations at the Muskeg
River Mine.
Request 71c Identify potential flocculants/thickeners (other than gypsum) that are being
considered.
Response 71c Alum is currently being investigated as an alternative to gypsum for creating
non-segregating tailings. The types of flocculants being considered are anionic
polyacrylamides, such as the Hychem AF246 flocculant currently used in the
thickeners at the Muskeg River Mine.
7-24 Shell Canada Limited April 2010
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