Myths and Misconceptions about Screening for Vapor Migration in Phase Is

Misconceptions with Vapor Misconceptions with Vapor Migration Screening using Migration Screening using ASTM E 2600-10 in a Phase ASTM E 2600-10 in a Phase

IIbyby

Anthony J. Buonicore, P.E., DEE, QEPAnthony J. Buonicore, P.E., DEE, QEPCEO, The Buonicore GroupCEO, The Buonicore Group

Chairman, ASTM Vapor Intrusion Task Chairman, ASTM Vapor Intrusion Task GroupGroup

for presentation atfor presentation at

EDR Due Diligence at Dawn SeminarEDR Due Diligence at Dawn SeminarSpring 2012Spring 2012

OverviewOverview

Top 10 Misconceptions about E 2600-Top 10 Misconceptions about E 2600-1010

Suggested Steps for Conducting a Suggested Steps for Conducting a Tier 1 VEC Screen as part of a Phase ITier 1 VEC Screen as part of a Phase I

Considerations in Making a VEC-REC Considerations in Making a VEC-REC DeterminationDetermination

Misconception #1Misconception #1

““Vapor migration screening is Vapor migration screening is not part of a Phase I unless not part of a Phase I unless the client asks for it or the the client asks for it or the state where the property is state where the property is located has vapor intrusion located has vapor intrusion regulations. Moreover, E regulations. Moreover, E 2600-08 says it is optional.”2600-08 says it is optional.”

WRONG!WRONG! E 2600-08 has been superceded by E 2600-10E 2600-08 has been superceded by E 2600-10 CERCLA definition of CERCLA definition of release release of of hazardous hazardous

substances substances includes “includes “emittingemitting” and ” and ““escapingescaping” ” into the environment into the environment (which (which includes “includes “into subsurface stratainto subsurface strata.”.”

AAI Rule says EP must provide “an opinion as AAI Rule says EP must provide “an opinion as to whether the inquiry has identified to whether the inquiry has identified conditions indicative of releases or conditions indicative of releases or threatened threatened releasesreleases of of hazardous hazardous substancessubstances……onon, , atat, , in or to the propertyin or to the property.”.”

WRONG!WRONG! ASTM E 1527 definition of a REC includes ASTM E 1527 definition of a REC includes

“presence or likely presence of any “presence or likely presence of any hazardous hazardous substancessubstances or or petroleumpetroleum productsproducts…indicate an …indicate an existing release, a past release or a material threat existing release, a past release or a material threat of a of a releaserelease……into structuresinto structures……into the groundinto the ground…”…”

CERCLA, AAI and the REC definition do not CERCLA, AAI and the REC definition do not differentiate “releases” by media, i.e., solid, liquid differentiate “releases” by media, i.e., solid, liquid or vapor.or vapor.

E 1527 is currently being revised to clarify that E 1527 is currently being revised to clarify that vapor migration must be treated no differently than vapor migration must be treated no differently than contaminated groundwater migration in a Phase I…contaminated groundwater migration in a Phase I…

E 1527 Ballot Revisions Clarifying that Vapor E 1527 Ballot Revisions Clarifying that Vapor Migration is to be Treated No Differently Migration is to be Treated No Differently

than Contaminated Groundwater Migrationthan Contaminated Groundwater Migration CERCLA definitions of “CERCLA definitions of “releaserelease” and “” and “environmentenvironment” added” added E 2600-10 specifically referenced in Documents Section Definition of “migration” added: “movement of hazardous

substances or petroleum products in any form, including solid and liquid at the surface or subsurface, and vapor in the subsurface” and specifically mentioned in a number of sections in the standard

Regulatory agency files should be reviewed if the property or adjoining identified in records research if EP judges that it is warranted – would assist in evaluating potential impact of vapor migration from nearby sites that have been “remediated” without vapor pathway considered

Non-scope considerations – Indoor Air Quality – clarified to say “unrelated to releases of hazardous substances or petroleum products into the environment”


“ “ The REC definition The REC definition includes releases or includes releases or threatened releases “into threatened releases “into structures” on the property. structures” on the property. This mean that vapor This mean that vapor intrusion into structures intrusion into structures needs to be evaluated in an needs to be evaluated in an ASTM E 1527 Phase I.” ASTM E 1527 Phase I.”

WRONG!WRONG!

Vapor intrusion assessment involves an indoor air Vapor intrusion assessment involves an indoor air quality evaluation. E 1527 specifically identifies quality evaluation. E 1527 specifically identifies indoor air quality as a “non-scope consideration” in a indoor air quality as a “non-scope consideration” in a Phase I.Phase I.

If a VEC exists or is likely or cannot be ruled out, and If a VEC exists or is likely or cannot be ruled out, and the EP determines that it represents a REC in the the EP determines that it represents a REC in the Phase I, a follow-on investigation can be conducted to Phase I, a follow-on investigation can be conducted to evaluate the potential for vapor intrusion. evaluate the potential for vapor intrusion.

If it is determined that a VEC can be ruled out If it is determined that a VEC can be ruled out because it does not exist or is unlikely to exist, then because it does not exist or is unlikely to exist, then the issue of whether vapors may intrude into the issue of whether vapors may intrude into structures on the property is moot.structures on the property is moot.


“ “ If a VEC exists or is If a VEC exists or is likely to exist, there is no likely to exist, there is no way to close a deal way to close a deal without an extensive site without an extensive site investigation that will investigation that will probably kill the deal.”probably kill the deal.”

WRONG!WRONG! If a VEC exists or is likely to exist or cannot be ruled out, If a VEC exists or is likely to exist or cannot be ruled out,

the deal can still be closed by doing “pre-emptive the deal can still be closed by doing “pre-emptive mitigation.” mitigation.”

Since vapor intrusion mitigation measures can be Since vapor intrusion mitigation measures can be estimated reasonably accurately (generally in the $2 – estimated reasonably accurately (generally in the $2 – $7/SF range, depending on mitigation measure), this cost $7/SF range, depending on mitigation measure), this cost can be used to adjust the deal price similar to the way can be used to adjust the deal price similar to the way that the presence of asbestos has been used to adjust the that the presence of asbestos has been used to adjust the deal price (since asbestos removal costs can also be deal price (since asbestos removal costs can also be estimated reasonably accurately).estimated reasonably accurately).

The cost to pre-emptively mitigate can be much less than The cost to pre-emptively mitigate can be much less than the cost to conduct a VI site investigation to determine if the cost to conduct a VI site investigation to determine if a problem really exists.a problem really exists.


““Both Tier 1 and Tier 2 Both Tier 1 and Tier 2 screening in E 2600-10 screening in E 2600-10 must be conducted to must be conducted to evaluate vapor evaluate vapor migration.”migration.”

WRONG!WRONG!

Tier 1 was designed as the Tier 1 was designed as the methodology for vapor migration methodology for vapor migration evaluation in a Phase I.evaluation in a Phase I.

If a VEC exists or is likely or cannot If a VEC exists or is likely or cannot be ruled out based upon the Tier 1 be ruled out based upon the Tier 1 evaluation, Tier 2 was designed as evaluation, Tier 2 was designed as the suggested follow-up (effectively the suggested follow-up (effectively equivalent to a “vapor” Phase II).equivalent to a “vapor” Phase II).


““Using the distances Using the distances specified in Tier 1 to specified in Tier 1 to identify the area of identify the area of concern results in too concern results in too many sites that need many sites that need evaluating. This can take evaluating. This can take significant time.” significant time.”

WRONG!WRONG! The Tier 1 distances for the AOC are just the The Tier 1 distances for the AOC are just the

starting point. They conservative and represent starting point. They conservative and represent 9090thth percentile plume lengths and widths! percentile plume lengths and widths!

The EP can reduce the Tier 1 distances The EP can reduce the Tier 1 distances significantly using professional judgment, e.g., significantly using professional judgment, e.g., with respect to groundwater flow direction, soil with respect to groundwater flow direction, soil characteristics, intercepting utility corridors, characteristics, intercepting utility corridors, etc.etc.

When the AOC is minimized using professional When the AOC is minimized using professional judgment, there will be far fewer sites that need judgment, there will be far fewer sites that need to be evaluated further.to be evaluated further.


““All VECs are RECs.”All VECs are RECs.”

WRONG!WRONG! Only for HUD multifamily Phase Is!Only for HUD multifamily Phase Is!

(Note: HUD projects involve (Note: HUD projects involve residentialresidential properties properties wherewhere

virtually all the vapor intrusion litigation can be found.)virtually all the vapor intrusion litigation can be found.) More often than not, VECs will not be RECs.More often than not, VECs will not be RECs. More often than not, a known or suspect More often than not, a known or suspect

contaminated site (with potential vapor migration) contaminated site (with potential vapor migration) located nearby and located nearby and up-gradientup-gradient from the TP would from the TP would have been judged a REC anyway from a have been judged a REC anyway from a groundwater migration viewpoint (irrespective of groundwater migration viewpoint (irrespective of the additional concern over vapor migration).the additional concern over vapor migration).

More on this later!More on this later!


““Vapor migration analysis Vapor migration analysis need only be performed need only be performed on RECs since a VEC on RECs since a VEC would have been a REC would have been a REC anyway.”anyway.”

WRONG!WRONG!

If vapor migration evaluations are only performed on RECs, If vapor migration evaluations are only performed on RECs, then the implicit assumption is that only contaminated then the implicit assumption is that only contaminated groundwater migration will be considered to determine if groundwater migration will be considered to determine if there is a REC. there is a REC. This will eliminate conditions that become This will eliminate conditions that become RECs solely because of the potential for vapor migration. RECs solely because of the potential for vapor migration.

For example…For example… If vapor migration is not being considered, a If vapor migration is not being considered, a down-gradientdown-gradient

nearby (but not adjacent) dry cleaner would not likely be nearby (but not adjacent) dry cleaner would not likely be considered a REC since the contaminated groundwater plume considered a REC since the contaminated groundwater plume would be moving away from the TP. However, would be moving away from the TP. However, today it may be today it may be considered a REC solely based upon vapor migration considered a REC solely based upon vapor migration potentialpotential (vapor migration does not have to follow (vapor migration does not have to follow groundwater direction, but rather the path of least resistance groundwater direction, but rather the path of least resistance which can be opposite groundwater flow direction).which can be opposite groundwater flow direction).


““There is no guidance on There is no guidance on evaluating VECs to evaluating VECs to determine if they are RECs.”determine if they are RECs.”

--

77

WRONG!WRONG! The best guidance is the REC definition The best guidance is the REC definition

itself and specifically the itself and specifically the de minimis de minimis definitiondefinition

Two conditions for Two conditions for de minimis de minimis - not a threat to human health and the environment - not a threat to human health and the environment

ANDAND

- would not be subject of an enforcement action if - would not be subject of an enforcement action if broughtbrought

to the attention of appropriate government agenciesto the attention of appropriate government agencies

De minimis De minimis conditions are not RECsconditions are not RECs More on this later!More on this later!


““The future use of a The future use of a property is not taken property is not taken into consideration in E into consideration in E 2600-10.”2600-10.”

WRONG!WRONG! For Tier 1 screening, distances are For Tier 1 screening, distances are

measured from a known or suspect measured from a known or suspect contaminated site contaminated site to the to the target property target property boundaryboundary

If vapors are likely to penetrate the If vapors are likely to penetrate the property boundary, then a VEC is likely property boundary, then a VEC is likely irrespective of the status of the propertyirrespective of the status of the property

Future use comes into play more often Future use comes into play more often than not with determining if the VEC is a than not with determining if the VEC is a RECREC


““E 2600-10 conflicts with E 2600-10 conflicts with state vapor intrusion state vapor intrusion guidance.”guidance.”

WRONG!WRONG! State guidance focuses on vapor intrusion State guidance focuses on vapor intrusion assessmentassessment

(and vapor migration from the source of (and vapor migration from the source of contamination – could be from the contamination – could be from the edgeedge of a of a contaminated soil or groundwater plumecontaminated soil or groundwater plume - to the - to the buildingbuilding))

E 2600-10 focuses on the potential for vapors to E 2600-10 focuses on the potential for vapors to encroachencroach upon the property, i.e., vapor migration from upon the property, i.e., vapor migration from a known or suspect a known or suspect contaminated site contaminated site to encroach to encroach upon the TP upon the TP boundaryboundary

E 2600-10 complements state guidance in that it E 2600-10 complements state guidance in that it effectively acts as a screening tooleffectively acts as a screening tool

If a VEC exists or is likely or cannot be ruled out, state If a VEC exists or is likely or cannot be ruled out, state guidance can assist in determining if the VEC is a RECguidance can assist in determining if the VEC is a REC

The jury is still out on… The jury is still out on… ““Dealing with nearby Dealing with nearby remediated/closed/NFA sites where vapor remediated/closed/NFA sites where vapor pathway was NOT taken into pathway was NOT taken into consideration.”consideration.”

Is it necessary to review the regulatory files?Is it necessary to review the regulatory files?E 1527 Task Group has proposed for the 2013 E 1527 Task Group has proposed for the 2013 revision to require the EPs to review pertinent revision to require the EPs to review pertinent regulatory files on nearby properties that in their regulatory files on nearby properties that in their judgment have the potential to impact the target judgment have the potential to impact the target property!property!

Suggested Steps for Conducting a Suggested Steps for Conducting a Tier 1 VEC ScreenTier 1 VEC Screen

(assuming no preferential pathways direct to the TP from (assuming no preferential pathways direct to the TP from

contaminated sites)contaminated sites) 1. Identify AOC and minimize to the maximum 1. Identify AOC and minimize to the maximum extent possible based on experienceextent possible based on experience

● ● Start out with 1/3Start out with 1/3rdrd mile or 1/10 mile or 1/10thth mile (for petroleum hydrocarbons), BUT mile (for petroleum hydrocarbons), BUT ● ● Can reduce significantly when GW flow direction known or can be inferred Can reduce significantly when GW flow direction known or can be inferred (from topographical data or nearby Phase II data or hydrologic data, etc.)(from topographical data or nearby Phase II data or hydrologic data, etc.) ● ● Can further reduce by using professional judgment based on local knowledgeCan further reduce by using professional judgment based on local knowledge ● ● Hydraulic barriersHydraulic barriers (such as rivers and wetlands) (such as rivers and wetlands) ● ● Sub-surface Sub-surface man-made physical barriersman-made physical barriers (preventing vapors (preventing vapors from reaching TP such as utility lines in a main road that can intercept from reaching TP such as utility lines in a main road that can intercept migrating vapors moving toward a TP)migrating vapors moving toward a TP) ● ● Sub-surface Sub-surface natural barriersnatural barriers (preventing vapors from reaching the TP (preventing vapors from reaching the TP such as confining layers, e.g., low permeability soil (e.g., clay layer) or such as confining layers, e.g., low permeability soil (e.g., clay layer) or fresh water lensfresh water lens

Net Reduction in AOC for Tier 1 Net Reduction in AOC for Tier 1 Screening of Screening of Known or Suspect Known or Suspect

COC SOURCESCOC SOURCES

E 2600-10 w/ E 2600-10 w/

Source LocationSource Location E 2600-10E 2600-10 Buonicore Buonicore Methodology*Methodology*

Up-gradient 1,760’ 1,760’Up-gradient 1,760’ 1,760’

Down-gradient 1,760’ 100’Down-gradient 1,760’ 100’

Cross-gradient 1,760’ 365’Cross-gradient 1,760’ 365’

* Buonicore, A.J. , * Buonicore, A.J. , Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Migration Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Migration

from Nearby Contaminated Sourcesfrom Nearby Contaminated Sources, Paper No. 2011-A-301, , Paper No. 2011-A-301, ProceedingsProceedings, Air & Waste Management Association, 104, Air & Waste Management Association, 104 thth Annual Annual

Meeting, Orlando, Florida, June 20-24, 2011.Meeting, Orlando, Florida, June 20-24, 2011.

Net Reduction in AOC for Tier 1 Net Reduction in AOC for Tier 1 Screening of Screening of Known or Suspect Known or Suspect

PHC SOURCESPHC SOURCES E 2600 Revised w/ E 2600 Revised w/

Source LocationSource Location E 2600-08E 2600-08 Buonicore Methodology*Buonicore Methodology*

Up-gradient 528’ 528’Up-gradient 528’ 528’

Down-gradient 528’ 100’ (LNAPL) Down-gradient 528’ 100’ (LNAPL)

30’ (dissolved)30’ (dissolved)

Cross-gradient 528’ 165’ (LNAPL)Cross-gradient 528’ 165’ (LNAPL)

95’ (dissolved)95’ (dissolved)

* Buonicore, A.J. , * Buonicore, A.J. , Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Migration Methodology for Identifying the Area of Concern Around a Property Potentially Impacted by Vapor Migration

from Nearby Contaminated Sourcesfrom Nearby Contaminated Sources, Paper No. 2011-A-301, , Paper No. 2011-A-301, ProceedingsProceedings, Air & Waste Management Association, 104, Air & Waste Management Association, 104thth Annual Annual

Meeting, Orlando, Florida, June 20-24, 2011.Meeting, Orlando, Florida, June 20-24, 2011.

Conducting a Tier 1 VEC ScreenConducting a Tier 1 VEC Screen cont’dcont’d

2. Are there any known or suspect COC-2. Are there any known or suspect COC- contaminated sites in the EP-defined AOC?contaminated sites in the EP-defined AOC? ● ● Government recordsGovernment records ● ● Historical researchHistorical research ● ● Other (?)Other (?)

3. Evaluate each site remaining in the EP-defined AOC3. Evaluate each site remaining in the EP-defined AOC ● ● Remediation status?Remediation status? ● ● Did remediation consider vapor pathway?Did remediation consider vapor pathway? ● ● Review AULs – contamination left on-site?Review AULs – contamination left on-site? ● ● Other (?)Other (?)


4. Identify VEC status4. Identify VEC status

● ● exists (physical evidence) exists (physical evidence)

● ● likely (within close proximity, e.g., two properties?) likely (within close proximity, e.g., two properties?)

● ● can not be ruled outcan not be ruled out (further away, beyond two (further away, beyond two

properties?)properties?)

● ● can be ruled out because it does not or is unlikely can be ruled out because it does not or is unlikely

to exist to exist

5. If VEC can be ruled out, vapor migration evaluation is5. If VEC can be ruled out, vapor migration evaluation is

completedcompleted


6. If VEC exists/likely/cannot be ruled out, 6. If VEC exists/likely/cannot be ruled out, determine if VEC is a RECdetermine if VEC is a REC ● “● “De minimis” (?)De minimis” (?) ● ● Apply state VI guidance criteria (?)Apply state VI guidance criteria (?) ● ● Other (?)Other (?)

7. If VEC is a REC, E 2600-10 Tier 2 provides a 7. If VEC is a REC, E 2600-10 Tier 2 provides a suggested vapor migration scope-of-work for follow-suggested vapor migration scope-of-work for follow- on investigation in Phase II (may also be part of a on investigation in Phase II (may also be part of a

Phase Phase II investigation into potential groundwater II investigation into potential groundwater contamination)contamination)

Considerations in Considerations in Making a VEC-REC Making a VEC-REC

DeterminationDetermination

Considerations Considerations

What is the What is the depth to contaminated depth to contaminated groundwatergroundwater? ? For example, VEC may exist or be For example, VEC may exist or be likely because of groundwater contamination on likely because of groundwater contamination on or near the TP, but a REC (due to vapor or near the TP, but a REC (due to vapor migration) may not exist (under the migration) may not exist (under the de minimis de minimis conditioncondition clause) because the depth to clause) because the depth to groundwater may be greater than the applicable groundwater may be greater than the applicable ASTM critical distance or distance identified in ASTM critical distance or distance identified in state VI guidance. [Of course, the presence of state VI guidance. [Of course, the presence of contaminated groundwater in and of itself may contaminated groundwater in and of itself may result in a REC anyway.]result in a REC anyway.]

Considerations Considerations cont’dcont’d Where is the Where is the nearest structure nearest structure on the TP on the TP

with respect to the contaminant plume? with respect to the contaminant plume? For For example, VEC may exist or be likely because of example, VEC may exist or be likely because of groundwater contamination on or near the TP, groundwater contamination on or near the TP, but a REC (due to vapor migration) may not exist but a REC (due to vapor migration) may not exist (under the (under the de minimis conditionde minimis condition clause) because clause) because the distance between the structure and the edge the distance between the structure and the edge of the contaminated plume may be greater than of the contaminated plume may be greater than the distance specified in state VI guidance. [Of the distance specified in state VI guidance. [Of course, the presence of contaminated course, the presence of contaminated groundwater in and of itself may result in a REC groundwater in and of itself may result in a REC anyway.]anyway.]

For example… For example…

●● NJDEP VI Guidance: NJDEP VI Guidance: distance horizontally distance horizontally or vertically between the or vertically between the nearest edge of nearest edge of the contaminated groundwater plumethe contaminated groundwater plume and and the the nearestnearest structurestructure on the TP, equal to on the TP, equal to

● ●100’ for COC or LNAPL PHC-COC100’ for COC or LNAPL PHC-COC

● ● 30’ for Dissolved PHC-COC30’ for Dissolved PHC-COC

For example…For example…

● ● State of Colorado is concerned when: State of Colorado is concerned when: ● ● Building “directly over or immediately adjacentBuilding “directly over or immediately adjacent to a subsurface source of contamination”to a subsurface source of contamination” ● ● Building “within one or two properties of the Building “within one or two properties of the plume boundary or approximately 100 ft.”plume boundary or approximately 100 ft.”

●● Colorado Indoor Air Guidance, September 2004Colorado Indoor Air Guidance, September 2004: : distance horizontally or vertically between the distance horizontally or vertically between the nearest edge of the contaminated groundwater plumenearest edge of the contaminated groundwater plume and the and the nearestnearest structurestructure on the TP, equal to on the TP, equal to

● ● 100’ for COC or LNAPL PHC-COC100’ for COC or LNAPL PHC-COC

ConsiderationsConsiderations cont’d cont’d

What is the What is the contaminant concentrationcontaminant concentration? ? For example, a VEC may exist or be likely For example, a VEC may exist or be likely because of groundwater contamination on or because of groundwater contamination on or near the TP, but a REC (due to vapor migration) near the TP, but a REC (due to vapor migration) may not exist (under the may not exist (under the de minimis conditionde minimis condition clause) because the volatile contaminant clause) because the volatile contaminant concentration is below the state risk screening concentration is below the state risk screening level for groundwater. [Of course, the presence level for groundwater. [Of course, the presence of contaminated groundwater in and of itself of contaminated groundwater in and of itself may result in a REC anyway.]may result in a REC anyway.]

Considerations Considerations cont’dcont’d

How has the How has the structurestructure on the TP been on the TP been designeddesigned? ? For For example, a VEC may exist or be likely because of example, a VEC may exist or be likely because of groundwater contamination on or near the TP, but a REC groundwater contamination on or near the TP, but a REC (due to vapor migration) may not exist (under the (due to vapor migration) may not exist (under the de de minimis conditionminimis condition clause) because the structure has been clause) because the structure has been designed to be designed to be intrinsically safeintrinsically safe from chemical vapor from chemical vapor intrusion, i.e., no vapor pathway to potential human intrusion, i.e., no vapor pathway to potential human receptors. Examples might include a building designed to receptors. Examples might include a building designed to operate 100% of the time under positive pressure, or operate 100% of the time under positive pressure, or condos with open-air parking directly below the units, or condos with open-air parking directly below the units, or buildings with radon mitigation systems. [Of course, the buildings with radon mitigation systems. [Of course, the presence of contaminated groundwater in and of itself may presence of contaminated groundwater in and of itself may result in a REC anyway.]result in a REC anyway.]

Where are there more likely Where are there more likely to be RECs to be RECs based solely on based solely on

vapor migrationvapor migration considerations?considerations?

Down-gradientDown-gradient known or suspect known or suspect contaminated sitescontaminated sites

Cross-gradientCross-gradient known or suspect known or suspect contaminated sitescontaminated sites

Vapor migration takes the path of Vapor migration takes the path of least resistance no matter what least resistance no matter what direction it is!direction it is!

Where is it more likely that Where is it more likely that what caused a VEC would what caused a VEC would

have been viewed as a REC have been viewed as a REC anyway even if vapor anyway even if vapor

migration was not migration was not considered?considered?

Up-gradientUp-gradient known or suspect known or suspect contaminated sitescontaminated sites

VEC-REC determination is impacted VEC-REC determination is impacted by:by:

State VI Guidance and E 1527-05 deState VI Guidance and E 1527-05 de

minimus criteria in REC definitionminimus criteria in REC definition Soil characteristics, subsurface Soil characteristics, subsurface

confiningconfining

layers and depth to water tablelayers and depth to water table Hydraulic barriersHydraulic barriers Physical barriersPhysical barriers Building design and location on Building design and location on

propertyproperty Building operationBuilding operation

Bottom LineBottom Line EP must consider vapor migration no differently EP must consider vapor migration no differently

than the way contaminated groundwater migration than the way contaminated groundwater migration is considered in a Phase Iis considered in a Phase I

EP can evaluate vapor migration using whatever EP can evaluate vapor migration using whatever methodology the EP determines to be appropriate methodology the EP determines to be appropriate (if not E 2600-10, then EP needs to document (if not E 2600-10, then EP needs to document “alternative” methodology and include “alternative” methodology and include documentation in the Phase I)documentation in the Phase I)

E 2600-10 Tier 1 screening methodology is an E 2600-10 Tier 1 screening methodology is an industry consensus methodology industry consensus methodology

E 2600-10 allows for EPs professional judgment and E 2600-10 allows for EPs professional judgment and is therefore able to “cover” virtually any is therefore able to “cover” virtually any “alternative” vapor migration methodology “alternative” vapor migration methodology (making a (making a strong case for using E 2600-10) strong case for using E 2600-10)

Bottom LineBottom Line If E 2600-10 Tier 1 screening indicates a If E 2600-10 Tier 1 screening indicates a

VEC, EP must then decide as part of Phase VEC, EP must then decide as part of Phase I if VEC constitutes a RECI if VEC constitutes a REC

- RECs can only be identified - RECs can only be identified through the ASTM through the ASTM

E 1527-05 standard practiceE 1527-05 standard practice

- RECs do not include - RECs do not include de minimisde minimis conditions conditions

E 2600-10 Tier 2 provides a suggested E 2600-10 Tier 2 provides a suggested

follow-on investigation of a Tier 1 VECfollow-on investigation of a Tier 1 VEC

Technology

Myths and Misconceptions about Screening for Vapor Migration in Phase Is