Discharge Monitoring 101

Monitoring of surface water discharge from the Pearce Creek Dredged Material Containment Facility (DMCF) is required by Special Condition #7 of the Water Quality Certification (WQC) issued by the Maryland Department of the Environment (MDE). The US Army Corps of Engineers Philadelphia District (CENAP) prepared a Discharge Monitoring Plan in compliance with the WQC requirements. The objective of the Discharge Monitoring Plan is to describe how the CENAP will monitor surface water discharge from the Pearce Creek DMCF for the constituents provided in the WQC. The Pearce Creek DMCF Discharge Monitoring Plan includes key parameters such as, but not limited to, flow volume/discharge rate, total suspended solids, pH, dissolved oxygen, nutrients, and metals. CENAP will provide all discharge data to MDE as it becomes available from the laboratory. A complete report containing all surface water discharge monitoring results and field methodologies will be provided to MDE on a monthly basis when discharge is occurring.

During inflow, water is added to facilitate the pumping of dredged material into the Pearce Creek DMCF. This excess water is discharged as effluent from the DMCF to provide the most capacity for dredged material placement, and to prevent overflow. The water inside the Pearce Creek DMCF will discharge through the sluice/weir box and travel through a channel that drains into the Pearce Creek Lake. Samples of the effluent will be collected at the sluice/weir box once per week during periods of discharge to monitor the surface water leaving the site per the Discharge Monitoring Plan. Daily composite samples will be taken during discharge to determine the total suspended solids concentrations. The volume of water discharging from the Pearce Creek DMCF weir will be measured over the entire discharge period as well. If the sample results are in compliance with the Maryland Surface Water Quality standard limits then discharge of water from the DMCF will occur/continue to occur. For more information, please see the MDE-approved Discharge Monitoring Plan.