Terraphase performed environmental assessments and remediation services at a shopping center formerly occupied by a dry-cleaning facility from 1930 to 1950 in the Hillcrest area of San Diego, California. Initial work included Phase I and II Environmental Site Assessments (ESAs) to characterize environmental impacts at the active shopping center and support the client’s property acquisition process by providing a clear understanding of environmental liabilities.

Scope of Services

Terraphase conducted multimedia environmental investigations, including soil, soil vapor, sub-slab vapor, indoor air, and groundwater sampling to evaluate the presence and distribution of tetrachloroethene (PCE). Subsurface characterization revealed complex geology, necessitating the use of multiple drilling methods, including rotosonic, hollow-stem auger, and air rotary casing hammer.

In 2014, the client entered a voluntary cleanup agreement under the California Land Reuse and Revitalization Act (CLRRA) with the San Diego Regional Water Quality Control Board (RWQCB). Terraphase developed a conceptual site model (CSM) and prepared an RWQCB-approved Response Plan proposing a full-scale soil-vapor extraction (SVE) system to remediate chlorinated volatile organic compounds (CVOCs). The SVE system is in operation and was expanded into target areas of residual contamination.

Terraphase currently performs semiannual groundwater and soil-vapor monitoring, and monthly SVE system operation and maintenance, in compliance with applicable air quality permits.

Notable Accomplishments

• Guided client through property acquisition with comprehensive environmental liability evaluation
• Installed and operated a full-scale SVE system, reducing PCE below regulatory criteria
• Successfully expanded the SVE system to target high-impact areas
• Achieved site-wide soil-vapor cleanup goals
• Developed and implemented a regulatory-approved Response Plan under CLRRA