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What the difference is, and why lawyers, bankers, regulators, and the regulated community should care Steve Crider May 7, 2014 Vapor Encroachment Screening.

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Presentation on theme: "What the difference is, and why lawyers, bankers, regulators, and the regulated community should care Steve Crider May 7, 2014 Vapor Encroachment Screening."— Presentation transcript:

1 What the difference is, and why lawyers, bankers, regulators, and the regulated community should care Steve Crider May 7, 2014 Vapor Encroachment Screening (VES) and Vapor Intrusion (VI) Assessment

2 News articles

3 Acronym list AOC:area of concern VES:vapor encroachment screen VEC:vapor encroachment condition VI:vapor intrusion TP:target property COC:chemical of concern LNAPL: light nonaqueous-phase liquids DNAPL: dense nonaqueous-phase liquids EP: environmental professional

4 Vapor encroachment and the vapor intrusion assessment process Are there actual or potential volatile vapors encroaching on the target property (TP)? (addressed by ASTM E ) If so, can these vapors migrate into structures on the property? (addressed by federal/state VI guidance) If so, can they represent an indoor air-quality problem? (addressed by federal/state VI guidance)

5 Informal survey: consultants and the vapor pathway MDEQ has focused on VI, May 2013 published a guidance document; ASTM updated Phase I ESA standard practice which now specifically mentions vapor, so are we, consultants, doing any better? Not yet −BEAs still targeting soil and groundwater −Vapor typically an afterthought during due-care planning process, resulting in: Insufficient or no vapor data Presumptive remedies −Of the five BEAs on desks of district staff, only one mentions vapor assessment in Phase I ESA

6 Root cause(s)??? Cost and time to conduct soil-gas sampling Soil gas not its own criteria; SVIIC and GVIIC not typically facility status drivers Vapors not thoroughly assessed or considered in Phase I ESA process

7 Using ASTM E or an alternative If a company develops its own methodology, it must be well enough documented in the Phase I ESA to allow a third party to reconstruct the analysis Advantages of using Tier 1 in ASTM E −Methodology standardized through ASTM consensus process −Developed by industry VI experts −Ability to use (without further documentation) critical distances in E −Reduced liability

8 ASTM E : overview NOT A REQUIREMENT FOR ASTM Standard guide not standard practice Focused solely on likelihood of migrating vapors to encroach on TP (creating a vapor encroachment condition, or VEC)

9 ASTM E : purpose Provide practical guidance and useful process for conducting a vapor encroachment screen (VES) on a property parcel involved in a real estate transaction in the U.S. with respect to chemicals of concern (COCs) that may migrate as vapors onto a property as a result of contaminated soil and groundwater on or near the property

10 ASTM E : objective Whether or not encroaching vapors result in intrusion requires investigation beyond scope of standard Objective: identify VECs, analogous to identifying Recognized Environmental Conditions in ASTM E1527

11 ASTM E : summary Two levels of screening for VECs: −Tier 1: focuses on known or suspected contaminated sites in AOC as identified in ASTM E1527 investigations (government records investigation, historical research, etc.) −Tier 2: focuses on plumes from any contaminated sites in AOC and their proximity (critical distance) to TP, or actual sampling to identify if vapors have encroached on TP

12 ASTM E : additional terminology Vapor encroachment condition (VEC) Area of concern (AOC) Critical distance

13 ASTM E : vapor encroachment condition Actual or likely presence of COC vapors in subsurface of TP, caused by release of vapors from contaminated soil or groundwater on or near TP

14 ASTM E : area of concern Measured from TP boundary to known or suspected contaminated property 1/3 mile for known or suspected contaminated sites with COCs (volatile or semivolatile hazardous substances) 1/10 mile for known or suspected contaminated sites with petroleum hydrocarbon COCs May be reduced in cross-gradient and side-gradient direction if groundwater flow direction is known

15 ASTM E : critical distance Defined as distance from nearest edge of contaminated plume to nearest TP boundary Measured linearly in any direction: horizontal, vertical, etc. 100 ft. for COCs 30 ft. for dissolved volatile petroleum hydrocarbons 100 ft. for petroleum LNAPL accumulating above water table What about DNAPL?: treat as COC

16 ASTM E : methodology Getting down to business

17 ASTM E : Tier 1 initial screening for VECs Designed as screening step to supplement Phase I ESA; relies on information already collected in investigation Review of governmental and historical records at specific search distances to identify COC-contaminated properties within AOC −1/3 mile for known or suspected contaminated sites with COCs (volatile or semivolatile hazardous substances) −1/10 mile for known or suspected contaminated sites with petroleum hydrocarbon COCs

18 ASTM E : most prevalent sources of concern Present and former: −Gas stations and auto repair sites −Scrap-metal sites −Manufactured gas plant sites −Dry-cleaning sites −Industrial sites, particularly those using chlorinated solvents for degreasing and parts cleaning −Municipal solid waste landfills and open dumps −Hazardous-waste disposal sites

19 ASTM E : Tier 1 AOC when groundwater flow direction can be estimated Upgradient −1/3 mile for COC sources −1/10 mile for petroleum hydrocarbon sources Downgradient −100 ft. for COC sources/petroleum hydrocarbon LNAPL sources −30 ft. for dissolved petroleum hydrocarbon sources Cross-gradient −100 ft. for COC sources/petroleum hydrocarbon LNAPL sources + plume-width consideration −30 ft. for dissolved petroleum hydrocarbon sources + plume-width consideration

20 ASTM E : net reduction in AOC for Tier 1 screening of known or suspected petroleum sources Source locationE E w/ Buonicore methodology* Upgradient528 ft. Downgradient528 ft.100 ft. (LNAPL) 30 ft. (dissolved) Cross-gradient528 ft.165 ft. (LNAPL) 95 ft. (dissolved) * Buonicore, A.J., Screening for Potential Vapor Intrusion Problems, Paper #129, Proc. AWMA 102 nd Annual Conference, Detroit, MI, June 16–19, 2009, and Buonicore, A.J., Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Mitigation from Nearby Contaminated Sources, Paper No A- 301, Proceedings, AWMA 104 th Annual Meeting in Orlando, FL, June 20–24, 2011

21 ASTM E : net reduction in AOC for Tier 1 screening of known or suspected COC sources Source locationE E w/ Buonicore methodology* Upgradient1,760 ft. Downgradient1,760 ft.100 ft. Cross-gradient1,760 ft.365 ft. * Buonicore, A.J., Screening for Potential Vapor Intrusion Problems, Paper #129, Proc. AWMA 102 nd Annual Conference, Detroit, MI, June 16–19, 2009, and Buonicore, A.J., Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Mitigation from Nearby Contaminated Sources, Paper No A- 301, Proceedings, AWMA 104 th Annual Meeting in Orlando, FL, June 20–24, 2011.

22 EDR VEC app

23 EDR VEC app (cont.)

24

25 ASTM E : EP judgment Type of TP Location of contamination source Cleanup status of contaminated site Depth to groundwater Soil characteristics Presence of “vapor conduits” (MDEQ favorite) Presence of hydraulic or physical barriers

26 ASTM E : Tier 1 conclusions 1.A VEC exists (physical evidence) 2.A VEC likely exists (within close proximity, e.g., two properties?) 3.A VEC cannot be ruled out (further away, beyond two properties?) 4.VEC can be ruled out because it does not or is not likely to exist (you are done!!)

27 ASTM E : Tier 1 conclusions (cont.) If 1, 2, or 3, determine if VEC is a REC if done in conjunction with Phase I ESA “De minimis” (?) Apply state VI guidance criteria (?) Other (?) If 1, 2, or 3, EP and user decide whether further investigation (such as proceeding to Tier 2 or state program) is warranted

28 ASTM E : Tier 2 more refined screening Non-invasive −If Phase II data on contaminated source exist, proximity of contaminated plume to TP is evaluated −Plume test / critical-distance evaluation

29 ASTM E : Tier 2 more refined screening Critical Distance 100 ft for NAPL COCs 30 ft for Dissolved Petro Critical Distance TP Property Boundary Existing or proposed building Vapor Conduits

30 ASTM E : Tier 2 invasive Invasive (soil, groundwater or soil gas sampling) −If Phase II data on contaminated source does NOT exist, or −If preferential pathway exists (natural or constructed), or −If VEC is identified in Tier 1 and you want to do confirmatory sampling (follow state program), or −If client or lender is more comfortable with sampling (follow state program). Sampling can be done at the TP boundary to identify whether vapors are encroaching on TP −Plume test / critical-distance evaluation

31 ASTM E : Tier 2 conclusions 1.VEC exists (physical evidence) 2.VEC likely exists (within close proximity, e.g., two properties?) 3.VEC cannot be ruled out (further away, beyond two properties?) 4.VEC can be ruled out because it does not or is not likely to exist (you are done!!)

32 ASTM E : Tier 2 conclusions (cont.) If 1, 2, or 3 then determine if VEC is a REC if done in conjunction with a Phase I ESA −“De minimis” (?) −Apply state VI guidance criteria (?) −Other (?) If 1, 3, or 3, EP and user decide whether further investigation (such as state program) is warranted

33 Why do we care about E if it’s not part of a Phase I ESA? ASTM E Section lists term VAPOR— so EP must consider it during Phase I ESA ASTM E2600 and Buonicore method provide hard numbers to rely on for determining REC or no REC Gut feelings are great, but having data to support your position helps lawyers sleep at night

34 Why do I care about E if it’s not part of a Phase I ESA? (cont.) Both ASTM E and E rely on EP’s professional judgment, so ultimately it’s still up to you Using guidance in E does not mean you have to write a full report…

35 Scope of work: Tier I Add-on to Phase I ESA −Modified questionnaire (see Appendix 3) −Report format follows 1527 so you need to add only subsections that discuss vapor in “records review, findings, opinions, and conclusions” section of report

36 Scope of work: Tier 2 Non-intrusive −More extensive file review of State/Local records −Letter-style report documenting reports reviewed and plume distances measured to nearest TP boundary (the critical-distance assessment) Intrusive sampling −Follow state guidelines

37 Final thoughts Not required for ASTM E , but a useful guide!

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