Laguna Lake Risk Assessment

The City of San Luis Obispo proposed a maintenance dredging regime over a four-year period at Laguna Lake to mitigate ongoing sedimentation. The Lake is situated on the 344-acre Laguna Lake Natural Reserve. Prior to dredging, Langan conducted a human health risk assessment (HHRA) to determine whether constituents in sediment and dried sediment (soil) pose unacceptable risks to human health under site-specific exposure conditions and to support decisions concerning the need for further evaluation or mitigation. The results of the HHRA demonstrated that existing conditions posed no unacceptable carcinogenic or non-carcinogenic risks to future receptors. Langan also supported the project’s CEQA analysis by developing project-specific avoidance and minimization measures for fugitive dust.