1. Common Issues for Exposure Scenarios without GNS VAP CP Summer Coffee July 14 th, 2015 Mike Allen Ohio EPA CO- Supervisor Michael.Allen@epa.ohio.gov

2. Today’s Discussion Group’s Intent on Providing Consistent Guidance Across DERR Programs Regarding Risk – RCRA Closure and Corrective Action – CERCLA Enforcement – Voluntary Action Program Land Use Restrictions and Maintenances in the VAP with emphasis on Scenarios without GNS

3. VAP Generic Numerical Standards and Land Uses Conservative Exposure Assumptions Recently updated to be comparable to the Regional Screening Levels (RSLs) Direct Contact Standards for Soils (DCSS) DCSS Residential Land Use ~ Unrestricted - Point of Compliance (POC) @ 10 feet bgs DCSS Restricted Residential ~ ‘Unrestricted’ POC @ < 10 feet bgs

4. VAP Generic Numerical Standards and Land Uses DCSS Commercial Industrial DCSS Construction Excavation Indoor Air Standards (Residential) Indoor Air Standards (Commercial/Industrial) Potable Use Standards for Ground Water; MCLs and Risk Based

5. Risk Guidance Documents http://www.epa.state.oh.us/derr/rules/guidan ce.aspx#119153115-risk-assessment http://www.epa.state.oh.us/derr/rules/guidan ce.aspx#119153115-risk-assessment Support Document for the Development of Generic Numeric Standards (Current and Past) Chemical Information Database and Applicable Relative Standards (CIDARS) Ecological Risk Guidance Some Remedial Risk Guidance etc.

6. Rules 3746-300-08 and -09 Generic Standards and Property Specific Risk Assessment Procedures Typical Property Specific Risk Assessments are Recreational and Ecological Rules are fairly prescriptive but some of the things to note – Nature and Extent – Identified Areas vs. Exposure Units and the control/understanding of these – Fraction Contaminated term – Toxicity Hierarchy

7. Rules 3746-300-08 and -09 Generic Standards and Property Specific Risk Assessment Procedures …..some of the things to note – Must be able effective at maintaining monitoring the property’s compliance with applicable standards – Engineering controls or use restrictions controlled with an OandM Agreement – POC maintained with an Environmental Covenant

8. Rules 3746-300-08 and -09 Generic Standards and Property Specific Risk Assessment Procedures Generic Standards for Restricted Residential (POC) Generic Standards for Indoor Air (Fraction Contaminated) Generic Standards for Commercial/Industrial – …Generic direct contact standards for commercial land use may not be appropriate for properties where a high frequency of potential exposure to children may occur, such as at schools and day care facilities.—What does this mean?

9. Commercial Industrial Generic Guidance Generic Standards for Commercial/Industrial – …….may not be appropriate for properties where a high frequency of potential exposure to children may occur, such as at schools and day care facilities.— Development of guidance for this is ongoing but the considerations include – Control and Risk understanding with O&M Agreement, Environmental Covenant – Toxicity considerations – POC

10. Commercial Industrial Generic Guidance Control guidance— How is the OandM agreement constructed in order to not endanger CNS voidance? Risk guidance– How are the exposure constructs labeled within a generic standard understanding? Toxicity guidance- Problematic COCs, Pb, VC, TCE? Mutagenic carcinogens?

11. Commercial Industrial Generic Guidance Ohio EPA is currently constructing some daycare like scenarios that will help us direct you more explicitly with regards to toxicity and exposure assumptions OandM use to maintain particular use structures on the Property is an option Combining Generic Standards with a quantitative demonstration for the receptors may be an option using Rule -09

12. Questions? Michael.Allen@epa.ohio.gov