Indiana Department of Environmental Management to Present Remediation Closure Guide and Remediation Program Guide to the Indiana Solid Waste Management Board

At 1:30 pm today, Tuesday February 21, 2012, the Indiana Department of Environmental Management (IDEM) intends to present its Remediation Closure Guide and Remediation Program Guide to the Indiana Solid Waste Management Board.  This will mark the final step in the two-year process undertaken by IDEM, with private industry input, to overhaul their subsurface environmental investigation and remediation Non-Rule Policy guidance. 

The soon to be replaced Risk Integrated System of Closure, or RISC program, has been in effect since February 2001 and has provided default cleanup levels for soil and groundwater in both residential and commercial/industrial scenarios in cookbook fashion.  Groundwater levels were established largely on health-based levels deemed safe for human consumption in residential and industrial exposure scenarios.  Soil levels were established primarily on the most conservative of direct contact, ingestion or migration to groundwater pathways, the latter of which was typically selected as default. Continue reading “Indiana Department of Environmental Management to Present Remediation Closure Guide and Remediation Program Guide to the Indiana Solid Waste Management Board”

IDEM’s Changes to TPH Procedures for Ground Water

Written by Steve Henshaw, P.G., President & CEO, EnviroForensics

On June 17, 2010 the Indiana Department of Environmental Management (IDEM) once again adjusted their guidance regarding the regulation of Total Petroleum Hydrocarbons (TPH) and revised pertinent sections of their Risk Integrated System of Closure (RISC) Technical Guidance Document.  A special RISC TPH Work Group has determined that the investigation, delineation and/or remediation of TPH in ground water are no longer warranted, unless protection of drinking water wells is necessary.  This development could significantly impact environmental cleanup projects where releases of petroleum products have occurred. 

The term TPH refers to an accumulation of hydrocarbon compounds that make up a variety of petroleum products.  Not all of the compounds that fall in this category have been researched individually by toxicologists, such that closure levels could be established.  Those that do have closure levels are considered Contaminants of Concern (COCs) at cleanup sites, which are commonly the more toxic compounds and are regulated individually.  The non-specific TPH is also regulated as a COC based on surrogate toxicological data.  Continue reading “IDEM’s Changes to TPH Procedures for Ground Water”