Groundwater and Discharge Monitoring for Tuller Avenue Remediation System

The Shell Tuller Avenue groundwater treatment system --designed, built and operated by WPI-- includes three air stripping towers, two chemical feed systems,  a regenerative thermal oxidizer (RTO), granular activated carbon (GAC) vessels, and a biological selenium removal system. The complete system also includes numerous underground vaults, containment areas, a two-story control building, a motor control center, transfer pumps, four  programmable logic controllers (PLCs), computerized data collection, and a human-machine interface (HMI) that integrates all control functions. Maximum capacity of the system is 300 gallons per minute.

 

The Tuller system operates under permits issued by the Los Angeles RWQCB (NPDES permit), South Coast AQMD (SVE system, air stripping system, and RTO), the Los Angeles County Dept. of Public Works (storm drain discharge), the Culver City Fire Department (hazardous materials storage), and the Los Angeles County Fire Department (waste reporting).

 

Monitoring of the Tuller system includes quarterly sampling of the pumping wells, and weekly/monthly collection of treatment system influent, intermediate, and effluent samples in compliance with the NPDES permit. Approximately 20 of the 50 related wells are located in the streets around the area and require traffic control for access.  Monitored parameters include petroleum hydrocarbons/oxygenates, and in-organics including metals. Annual testing for aquatic toxicity, priority pollutants, dioxin, and asbestos is also performed.

 

Routine reporting required by the Regional Water Quality Control Board-Los Angeles Region includes Monthly Groundwater Remediation System Updates, Quarterly Groundwater Remediation Progress Reports, Quarterly Groundwater Discharge Monitoring Reports (NPDES compliance), Annual Groundwater Discharge Monitoring Reports (NPDES compliance), and Quarterly Monitored Natural Attenuation (MNA) Reports. Additional documents required for NPDES Permit  compliance includes a Storm Water Pollution Prevention Plan and a Toxicity Reduction Evaluation workplan.