PLANNING AHEAD:  When contaminated soil and groundwater are left in place and not removed, tracking the migration and status of the residual contaminants are not covered in the LTCP.  These hazardous compounds may underlie nearby properties or utility corridors.   Construction and utility workers may be exposed to unidentified residual contaminants unexpectedly while working on a subsurface project.  Researching nearby sites on Geotracker (http://geotracker.waterboards.ca.gov/) and other databases prior to excavation will help to identify nearby sites that may contain residual contamination prior to any possible worker exposure or job shut-down.

Although LTCP is now the policy, both 1) worker exposure through OSHA laws and also 2) lending issues for banks have not changed in response to LTCP.  Communicating the remaining hazards, if any exist, and proper disclosure for real estate transactions, are important steps to avoid possible exposure issues or litigation for sites or areas with residual contamination left in place.

Evaluating potential future issues is appropriate for planners and investors who might try to change future use of a site closed by LTCP.  The standards for continuing obligations for residual contamination have been established by ASTM international (ASTM E2790-11).

Humboldt County, Department of Health and Human Services, requires a  Soil Management Contingency Plan for sites with remaining contamination, to address the potential for construction workers and any others who might be exposed to buried contaminants in subsurface soil and in groundwater.


ASTM E2790 11, the Standard Guide for Identifying and Complying with Continuing Obligations, provides guidance in regards to residual contamination.

Geotracker: http://geotracker.waterboards.ca.gov/

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