Performance of sediment control settling ponds, Texada Quarry Mountjoy, K. J. (Keith J.); Diggon, Harold M.; Vickery, B. J. (Brendan J.)
In early 1998, environmental monitoring at the Texada Quarry revealed large amounts of sediment were generated by quarry operations and transported in surface water run-off containing high levels of suspended solids at various locations throughout the quarry. In order to control sediment transport at the Texada Quarry operations and prevent discharge into the receiving environment, two sediment control settling ponds were designed and constructed: the Main Settling Pond (MSP) and Ancillary Settling Pond (ASP). The design and construction were completed in 1998. A monitoring program was implemented under Permit Q-15 to assess the performance of the settling ponds, with effluent criteria set at 75 mg/L TSS. Monitoring has been conducted on a monthly basis since construction in 1998. Monthly monitoring data from August 1998 to July 2003 indicate that the MSP effluent was above the 75 mg/L total suspended solids on only three of sixty occasions, despite peak total suspended solids in excess of 10,000 mg/L. With one exception, the ASP effluent has been consistently below 75 mg/L effluent criteria. Influent total suspended solids during this same period reach maximum levels of approximately 600 mg/L. Correlation of TDS and turbidity for effluent suggests that field measurement of turbidity could be used to develop a turbidity threshold for determining if the MSP and ASP effluent were below or above the regulated effluent criteria. This would also for a reduction in analytical costs associated with this monitoring program. The design, installation, monitoring and annual maintenance of these settling ponds has been successful in mitigating impacts to the receiving environment from the quarry operations.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International