Sacramento Housing and Redevelopment Agency (SHRA) retained Partner to characterize and remediate lead in on-site soil before redevelopment of the site with a residential housing community, park, and community garden. Before soil characterization and remediation activities, Partner prepared a Sampling and Analysis Plan (SAP) in accordance with Department of Toxic Substances Control (DTSC) guidance.

Twin Rivers (Mirasol Village) in Sacramento, California

The soil characterization process consisted of dividing each of the redevelopment areas into sub-areas using a grid and collecting soil samples from depths of 0.5 and 2 feet below ground surface within the center of each sub-area. Areas where the grid samples exceeded the DTSC screening level (SL) for lead in residential soil were remediated by soil excavation. Soil excavation was deemed complete when excavation confirmatory soil samples were below the DTSC SL.

Challenges

During site grading activities, two water wells were discovered. SHRA relied on Partner for permitting, procuring a licensed driller, and overseeing the proper destruction of the water wells.

Benefits

The developer’s consultant recommended the removal of the top 12 to 24 inches of soil across the site (approximately 12.5 acres) to address potential lead in soil impacts. Partner’s approach of characterizing lead impacts in soil at the site prior to soil excavation reduced remediation costs and allowed the site development to proceed promptly.

Project Highlights

Remediation was performed to the satisfaction of the developer’s consultant, resulting in meeting development milestones.