IDEM Issues New Remediation Screening Levels
By Andy Bowman, Attorney, Bingham Greenebaum Doll LLP
On March 1, 2013, the Indiana Department of Environmental Management (IDEM) published the first annual revision of the screening levels that appear in Table A-6 of the 2012 Remediation Closure Guide (2013 Screening Levels Table). The screening levels are one option for selecting remediation objectives at sites where releases have occurred and often are used to inform environmental investigations. IDEM’s screening levels are based upon, with certain modifications, EPA’s Regional Screening Levels (RSL). IDEM reviews the RSL in effect at the end of each calendar year to revise its screening levels.
According to IDEM the 2013 Screening Levels Table includes all of the chemicals listed in the 2012 Table plus the following seventeen newly-listed chemicals: aldicarb sulfoxide; boron trichloride; 2-chloroethanol; cyclohexene; tetrahydrofuran; hexamethylphosphora-mide; nitrate + nitrite (as N); di-N-octyl phthalate; sulfolane; thallium (I) nitrate; thallium acetate; thallium carbonate; thallium chloride; thallium sulfate; triacetin; tris(1-chloro-2-propyl)phosphate, and zirconium. The 2013 Screening Levels Table is easier to use now that all of the chemicals are listed in alphabetical order rather than using the chemical groups that appeared in the 2012 Table.
While the 2013 Screening Levels Table includes some two hundred changes, many of the changes are relatively minor or involve chemicals not commonly found at sites. However, IDEM’s announcement noted that changes in toxicity parameters have resulted in new screening levels for the following five chemicals often found at sites: cyanide, 1-methylnaphthalene, 2-methylnapthalene, methylene chloride, and tetra-chloroethene (PCE).
The soil direct contact screening level for lead at commercial/industrial sites was lowered from 1,300 mg/kg to 800 mg/kg, consistent with EPA’s screening level. In addition, the excavation worker screening level for lead is now rounded up to 1,000 mg/kg from the 2012 level of 970 mg/kg. IDEM also raised the recreational soil direct contact screening levels for lead from 400 mg/kg to 800 mg/kg for each of the three recreational scenarios.
A six-month transition period applies to the new screening levels.
To view a complete PDF of the January/February 2013 issue of the Environmental Letter, click HERE.