Pierre River Mine Project

WATER ERCB SIRS 46 – 79
Question No. 55
Section 7.1
Request Volume 1, Section 13.1, Page 13-23, Supplemental Information Responses.
Shell states, “Groundwater quality will be considered acceptable when it can be
demonstrated that, when released, it would have no adverse effects on the health
of aquatic, terrestrial or human receptors.” Shell further states, “The actual
percentage of seepage captured and sent back to the ETDA will depend on the
results of the groundwater monitoring program that will be implemented to
monitor the effectiveness of the mitigation measures (see EIA, Volume 4B,
Appendix 4-9, and Section 2.1.4.3). If unacceptable quality is detected in
groundwater originating from the ETDA, a groundwater response plan will be
implemented.”
55a Provide the discharge criteria that Shell will use to assess acceptability of
released groundwater.
Response 55a As described in the response to ERCB SIR 56, groundwater discharge criteria
that will be used to assess the release acceptability will be evaluated using the
following criteria:
• a comparison against pre-mining or statistically established background
values
• a comparison against acceptable criteria, which may include Canadian Water
Quality Guidelines, CCME, or ecological risk assessment methodologies
Request 55b Provide details on the proposed monitoring program in terms of well locations,
depths, and measured water quality parameters.
Response 55b The EIA, Volume 4B, Appendix 4-9, Section 2.1.4.3 indicates that “monitoring
wells will be installed along the perimeter of the ETDA in both the shallow and
deep Quaternary deposits to monitor seepage and the effectiveness of the
mitigation measures.”
A list of analytical parameters to be measured to determine groundwater quality
is provided in EIA, Volume 4B, Appendix 4-9, Section 2.1.3, Table 1.
Request 55c What are the triggering criteria for considering the groundwater quality
unacceptable?
Response 55c The triggering criteria for considering the groundwater quality unacceptable
would be based on a comparison against acceptable criteria, which may include
Canadian Water Quality Guidelines, CCME, or ecological risk assessment
methodologies.
7-8 Shell Canada Limited April 2010
CR029