Challenges

• Establishing origin of water in interstitial space of a process pond liner and secondary containment layer
• Increasing numbers of groundwater samples and detailed analyses required for compliance monitoring resulting in increasing costs of laboratory analysis and reporting effort
• Hydrocarbon exceedances of regulatory criteria in areas considered unimpacted

Solutions

• KCB developed a hydrogeological investigation plan to assess origin of recurring water presence in interstitial space. Work involved installation of monitoring wells, assessing local groundwater gradients and chemistry, and analysing data to determine if initial water was from natural sources or from pond liner leakage.
• KCB proposed, and gained regulatory acceptance for, the use of an indicator parameter approach for surface and groundwater compliance monitoring. Sampling, analysis and reporting reduced to eight primary indicator parameters, selected based on their relationship with potential contaminants of concern related to the SAGD facility operations.
• Chromatogram comparison used by KCB to show hydrocarbon exceedances in a peat unit were due to biogenetic processes rather than facility operations.

Successes

• Results indicated the water found in interstitial space was a combination of natural groundwater mixing with surface runoff that was entering the system through poor seals between liner layers around the periphery of the pond. Primary liner was concluded to be intact and functioning as per design.
• Achieved regulatory acceptance of an alternate and less intensive monitoring and reporting program. Reduced costs associated with sampling, data analysis, and reporting, while still maintaining effective compliance monitoring for potential facility related impacts.
• KCB played key role in assisting client in providing the regulator with a scientific basis for hydrocarbon exceedances and maintaining compliance.