This is a complex accelerated evaluation of the nature and source of hydrocarbons seeping from under a portion of a major drainage channel in suburban Los Angeles. Interim response measures are in place pending alternate long-term response action development and implementation.

A 2.5-acre free product plume recovered from 50 feet below the ground surface over three separate retail sites, plus offsite impacts in densely populated areas, are being remediated with one system. This site will be ready for closure in 2024-2025.

A commingled plume from two site releases on Long Island impacts a sensitive potable water aquifer. While site remediation is complete, ongoing effort to define the vertical and lateral extent of the plume continues to determine if a longer-term remedial effort is needed other than MNA. Access is a challenge within the residential and commercial areas of the project.

Several plumes, including two separate commingled plumes, are being addressed associated with this industry terminal complex involving four companies. The resolution of potential offsite impacts and remediation of several source areas continues. Resolving these issues from a regional perspective is critical to be successful and effective.

This project involves three terminals and an industry pump station. Release over the years has resulted in single terminal plumes, as well as several commingled multi-party plumes. Each release and plume have been identified. Selective remedial measures are in place. However, further selective assessment is underway, with a remedial response to follow, including addressing offsite impacts.

Public wells impacted with 22 potential UST sites involved with expedited site response and regional approach with non-RELLC PRP; project successfully closed.

Three sites with over 200,000 gallons of equivalent gasoline were recovered before reaching closure.

Three terminals efficiently and expeditiously closed, with impacts to private residential wells resolved.

Two terminals with threatened impacts to the creek and drinking water reservoir were resolved, with remedial activity completed.

Two typical former UST sites with common impacts were resolved using two different technical solutions with site closure.

Three previously closed sites were re-opened to aggressively address impacts discovered during a major 18-acre urban redevelopment project with significant construction in 2018. The project was successful, with no construction delays for redevelopment.