1. Bill Janes and Earl Crapps Department of Environmental Conservation Division of Spill Prevention and Response Contaminated Sites Program

2. Presentation Overview  Site cleanup rules background  Multi-phase revision approach  Modifications effective October 8  Petroleum Issues  Audience discussion and input

3. Cleanup rules (18 AAC 75.325-390) developed over 10 years ago - no major changes since Default cleanup levels in look-up tables Risk-based approach allows for alternative cleanup levels Similar regulations for regulated UST cleanups developed in early 1990s (18 AAC 78) Cleanup levels in 75 adopted by reference Lab approval program in 78 Differences in terminology and procedure

4.  Phase I - Completed Updated Table B1 and Table C cleanup levels Updated several other technical requirements Addressed certain policy issues Performed housekeeping

5.  Phase II (current) and Beyond  Update technical and policy requirements  Merge 75 and 78 cleanup sections  Introduce a new QA/QC section  Develop clear and consistent submittal review and approval criteria

6.  Phase II and Beyond  Clarify regulation, procedure, and guidance  Perform regular housekeeping  Evaluate and possibly revise the petroleum fraction cleanup levels

7.  Q&A Fact Sheet  Comment response summary  Summary of 2008 Proposed Changes  Revised Regulations  Cleanup Levels Guidance  Cumulative Risk Guidance  Soil Water Partitioning Equation Tech Memo  Cleanup Levels Comparison Spreadsheet  Regulations Update Presentation (Nov. 2008)  Petroleum Cleanup Levels Discussion Paper

8.  Changed cumulative non-cancer HI to one significant figure (325 (g) and (h)  Updated citations - ADF&G, ADNR, Standard Methods, ASTM, 40 C.F.R. (325 h and k)  “Ingestion” replaced with “Direct Contact” (340)  Cleanup level tables updated (341 and 345) Uses Risk Assessment Information System (RAIS) Added new chemicals to tables Statewide migration to groundwater cleanup level

9.  Added new column to cleanup level tables to distinguish between carcinogenic and non- carcinogenic contaminants  Repealed the GW “10X” cleanup level option (345 (b)(2))  Clarified when the department may eliminate the use of institutional controls (375(f))

10.  Updated regional master discharge prevention and contingency plan boundary for Western AK  Clarified definition of “carcinogen” (990 (12)  Placed definition of “risk assessment” into regulation (990(109)

11.  Revised soil-water partitioning equation Fixed mixing zone depth of 5.5 meters Technical memo provides detailed discussion  http://www.dec.state.ak.us/spar/csp/guidance/soil.water.part_tm.pdf http://www.dec.state.ak.us/spar/csp/guidance/soil.water.part_tm.pdf  Added default Surface Area and Adherence Factors to commercial/industrial cleanup levels

12.  Added Absorption Factor (ABS) column for chemicals that have dermal risk effects for dermal contact pathway  Added “selection of compounds for dermal absorption” section

13.  Added PAHs to the indicator compounds table  Added table of fugitive dust COPCs  Updated compounds that exceed cancer risk standard and HQ of 1.0 at the Table C groundwater cleanup levels

15. No technical basis for the petroleum maximum allowable concentrations Request to move the maximum allowable issue to phase 2 of the regulation revisions Objection to a rigid concept regarding maximum allowable concentrations Maximum allowable concentrations create unreasonable demand for cleanup and a marginal reduction in risk at high cost

16. Request to use SOC papers to develop technically accurate and defensible migration to groundwater cleanup levels for petroleum Objection to applying a statewide migration to groundwater cleanup level to Arctic sites

17. Objection to applying the three-phase equation to both vadose zone and saturated zone soils Objection to rescinding the aliphatic/aromatic cleanup levels; important scientific link to the total fractions broken Petroleum fraction cleanup levels do not reflect how fuels migrate in the subsurface Fuel contamination in groundwater generally due to smear zone contact, not leachate migration through soil

18.  DEC considering repeal in order to simplify regulations and follow current practice  Technical foundation for the total GRO, DRO, RRO cleanup levels would remain

19. Option:  Rename as “residual saturation levels” Revise to 1,000, 2,000, and 5,000 mg/kg for GRO, DRO, RRO respectively Add text to regulations to clarify they are screening levels only Indicate a risk of NAPL migration if exceeded Option:  Interpret literally as not-to-exceed thresholds

20.  Applicable to groundwater contamination  Drinking Water Program does not regulate the petroleum fractions  Creates regulatory inconsistency

21.  Constituent based – targets individual compounds such as benzene  Risk assessment evaluation on a case-by-case basis  Subjective/arbitrary cleanup levels  TPH approach  Fuel Fractions – Cleanup levels range widely from state-to-state

22.  Three-phased approach may be overly conservative Above Csat - risk remains constant  Options: Allow for 4-phase partition modeling Allow for greater use of leaching analyses Three- and Four-Phase Partitioning & Human Health Risk Calculations Technical Background Report (Geosphere, CH2MHill, 2005)

23.  Current DRO and RRO ranges selected in mid-1990s as a matter of convenience Allowed for continued use of AK 102 and 103  Ranges not consistent with TPHWG recommendations or available data

24.  Calculated GRO groundwater cleanup is 7.3 mg/L for aromatics and 182.5 mg/L for aliphatics Used to calculate GRO method 2 migration to gw soil cleanup level As a conservative measure DEC defaulted to the calculated GRO solubility, 1.3 mg/L, for the gw cleanup level  Calculated solubility not used for DRO gw cleanup level; instead the aromatic fraction (1.5 mg/L was used)

26. Washington DRO Cleanup Level ( 2,000 mg/kg)  “Note that recently, the National Institute of Environmental Health Services has announced that naphthalene, a diesel fuel component, causes cancer in animals. If EPA proceeds with  development of a cancer potency factor for naphthalene, this could result in a much lower ground water cleanup level for naphthalene than is currently allowed under Method B, and consequently, a lower soil cleanup level for diesel range organics.” (Concise Explanatory Statement - MTCA Cleanup Regulations – February 2001)

27.  Soil – Direct Contact Butylbenzylphthalate Endrin Tetrachloroethene (PCE) Trichloroethene (TCE) Xylenes (total)

28.  Soil – Outdoor Air Inhalation 1,4-Dichlorobenzene Hexachloro-1,3-butadiene PCE 1,2,4-Trichlorobenzene TCE

29.  Soil – Migration to Groundwater Aldrin Bis(2-ethylhexyl)phthalate Bromodichloromethane Butylbenzylphthalate p-Chloroaniline Chlorodibromomethane (also called Dibromochloromethane) DDD DDE DDT Di-n-butylphthalate Di-n-octylphthalate Heptachlor Heptachlor epoxide Hexachlorobenzene Hexachloro-1,3-butadiene Hexachlorocyclopentadiene Hexachloroethane

30.  Groundwater Bromodichloromethane p-Chloroaniline Chlorodibromomethane (Dibromochloromethane) 