RECAP Implementation Issues

1. RECAP  Implementation Issues 

2. Transition to the 2003 RECAP The management of an AOC/AOI may continue under RECAP 2000 until the current phase/task of the project has been completed and approved by the Department. Further assessment of the AOC/AOI shall be under RECAP 2003 unless otherwise approved by the Department.

3. Transition to the 2003 RECAP • Pick a version and stick with it • RECAP 2003 is more flexible with more tools • RECAP 2000 is an option if the investigation was begun under RECAP 2000

4. TPH Issues • TPH-GRO and DRO ranges redefined Not necessary to re-analyze just to account for 2003 TPH fractions! • Added TCEQ Methods 1005 and 1006 • Omitted Washington method for TPH fractions - SO, MO-1, MO-2 - soil and groundwater

5. TPH Issues • Use aliphatic and aromatic fractionations as final remedial standards whenever possible • RECAP Appendix I applies to most petroleum releases, not just UST sites • Enclosed space does not preclude the use of Appendix I.

6. TPH Issues • Only TPH-G and/or equivalent fractions, not TPH-D or TPH-O, require sample collection using 5035 • Only TPH-G and/or equivalent fractions not TPH-D or TPH-O require evaluation for volatilization into an enclosed space

7. TPH IssuesSw and L • Sw and L are used in determination of DF • Applies to vadose (unsaturated) zone only! -not smear zone • Identify borings with COC soil concentration > SS above the zone of groundwater fluctuation (not smear zone) • Typically 30’ X 30’ for most UST site AOIs

8. Institutional Controls • ·If the residual COC concentration in soil is > Soilni, then a conveyance notification shall be place on the property. • ·If the residual COC concentration in a groundwater 2 aquifer is > GW2 (w/o DF2), then a conveyance notice shall be place on the portion of the plume within the property boundaries. *Does not apply to GW1 or GW3

9. Identification of Landowners and Easement/Right-of-Way Holders The Submitter shall identify the name and mailing address of all other landowners and easement/right-of-way holders whose property is within an AOI.

10. Identification of Landowners and Easement/Right-of-Way Holders • Applicable property boundary standards • Soilni • MCL or drinking water standard for GW1/2 • Use of DF3 for GW3 aquifer does not trigger notification • Enclosed space standards if applicable • Likely offsite impact (common sense)

11. Voluntary Remediation Program(VRP) • Only requires on-site delineation of nature and extent • Waiver of Liability • Possible pathway elimination based on intended use

12. Soil Intervals • Current/potential surface soil 0-15’ • Soili/ni, SoilGW , Soilsat and Soiles • Subsurface soil >15’ bgs • SoilGW and Soilsat

13. Ambient and indoor air issues • Errors in RECAP Table H-5 (Cai) • These result in Soiles/GWes errors in Tables 2 and 3 of RECAP • These errors will be addressed through rulemaking

14. Soil Gas • Soil gas as an alternative to Soiles/GWes • May be used in RECAP MO-2 or MO-3 • Soil gas sampling protocol to be available on RECAP website soon • Compare Soil gas results times Alpha to Ca *Alpha = attenuation factor (0.01)

15. Background • Number of samples - site-specific background A minimum dataset consisting of 4 discrete samples from unimpacted area • Arsenic background of 12 mg/kg Compare average of site samples to 12

16. Conceptual Site Model • Identification of exposure pathways  is done a step before the estimation of exposure concentrations • a pathway is complete if there exists a unique mechanism by which a population may be exposed to the chemicals at or originating from the site

17. Self Implementation • Phase II site investigations • Small, quick or interim clean-ups • Reporting requirements and Department notification must be met. • Bad idea for larger or more detailed sites/investigations – all work done at own risk

18. Reminders/ Useful RECAP Tools

19. foc • MO-2 and MO-3 only • Changes (raises) Soili, Soilni, Soilgw, Soilsat and Soiles • Sample must be taken from un-impacted area of site • Be sure to check sample location and lab analysis • ASTM 2974 Foc = % organic matter /174

20. Foc – impact on benzene RS

21. SPLP • Alternative evaluation of soil to ground water pathway • Replaces and supercedes Soilgw • May be used under any MO, including SO • Sample must be taken from location with highest constituent concentration • EPA Method 1312

22. SPLP • GW1 – compare soil SPLP to GW1 X (20) • GW2 – compare soil SPLP to GW2 X 20 X DF2 • GW3 – compare soil SPLP to GW3 X 20 X DF3 • AOIC must still meet lower of Soili and Soilsat

23. Addressing Exposure to MultipleConstituents that Elicit Noncarcinogenic Effects on the Same Target Organ/System • Risk-based RS must be adjusted to account for potential additive effects • Soilni, Soili, Soiles • GW1, GW2, GWes • Not applicable to SoilGW, Soilsat, GW3, Watersol, background levels, quantitation limits, MCLs or ceiling values

24. MO-1: Accounting for AdditivityExample Chemical Target Organ RS Adjusted RS A kidney 24 8 B kidney, liver 15 5 C kidney 60 20 • Divide the RS for A, B, and C by 3 (kidney) (Same as calculating a RS using a THQ of 0.33)

25. MO-1: Accounting for AdditivityExample Chem. Target Organ RS Adjusted RS [COC] A kidney 24 8 18.0 B kidney, liver 15 5 3.0 C kidney 60 20 2.0 • Divide the RS for A, B, and C by 3 (kidney) (Same as calculating a RS using a THQ of 0.33)

26. Hazard Index Approach to Adjustments for Additive Effects • MO-2 and MO-3 only • Just like MO-1 approach, applies only to direct human health-based standards, e.g. Soili, Soilni, GW1, GW2 and Soiles. • Do not blindly divide by the number of constituents!

27. Hazard Index Approach THIkidney = ECA/RSA + ECB/RSB + ECc/RSc where: EC = exposure concentration RS = RECAP Standard THIkidney = 18/24 + 3/15 + 2/60 = 0.98 • THI must be < 1.0

28. RECAP QUESTIONS?