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HOAI TRANU.S. ENVIRONMENTAL PROTECTION AGENCY, REGION 7
VIENNA, MISSOURIJULY 11, 2017
Proposed Plan at the Vienna Wells Site
1
Questions That Will Be Answered• What is Superfund?• What is the Remedial
Process? • Vienna Wells Site
• Remedial Investigation• Feasibility Study• Proposed Plan• Record of Decision
2
What is Superfund?• Law passed in 1980 by
Congress – Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
• Two provisions under CERCLA:
• Gave the federal government the authority to clean up hazardous waste sites
• Established the Hazardous Substance Trust Fund, commonly called Superfund, to pay for cleanups
3
PRP Search/lnvotvement Community Involvement
Integrated Assessment (Rermv• & Rerred 1.1I)
Goals of Superfund
• Protect human health and the environment by cleaning up polluted sites
• Involve communities in the cleanup process
• Return previously-polluted land to productive use
4
Vienna Wells Site• Three
contaminated public drinking water wells
• Source area is the former Langenburg Hat Factory
• Fund-lead Site, managed directly by EPA
5
What is the Remedial Process?
• Blueprint by which EPA investigates a site and evaluates, selects, and implements a remedy
• Remedial Project Manager oversees the process
• Begins when a site is placed on the National Priority List (NPL)
6
Remedial Process 7
PRP Search/Involvement Community Involvement
Integrated Assessment (Rerroval & Remech,ll
To Removal Program if Necessary
Pre-Remedial Activities8
PRP Search/Involvement Community Involvement
Integrated Assessment (Rerroval & Rerredol)
Pre-Remedial Activities• Discover & Notification – PCE was first
detected in City Well #1 in 1994• Preliminary Assessment – MDNR completed
PA on March 28, 2007• Site Investigation – MDNR completed SI on
March 31, 2009• National Priorities List – Final NPL on
September 29, 2010
9
Remedial Investigation10
PRP Search/ Involvement Community Involvement
Integrated Assessment (Rerrov~ & RerredlBI)
To Removal Program if Necessary
• Gathering more site information to help identify what is needed for cleanup• Types of chemical• Amount of chemical• Types of media (soil, groundwater, surface
water, or air)• Determine health and environmental exposure
11Remedial Investigation
• United States Geological Survey (USGS) began RI in 2011
• Phased Approach• Phase 1 – General reconnaissance and area-wide
sampling to search for other possible sources
• Phase 2 – Sampling of the hat factory to characterize source area
• Phase 3 – Sampling to address data requirements of the baseline risk assessment
12Remedial Investigation
Phase 1 - Activities• Area Wide Investigation• Phase 1 Activities
• Interviews with local residents and former employees of hat factory
• Review of historical maps and photos• Detailed reconnaissance of hat factory property• Sampling of creeks, seeps and sewer systems• Sampling of public and domestic wells• Geophysical logging
13
Phase 1- Conclusions• Primary contaminant is Tetrachloroethene (PCE)• Hat factory is the only source area (no other
source found)• No domestic drinking water wells are impacted by
PCE• Surface water (streams, seeps and storm sewers)
are generally not impacted by PCE
14
Phase 2 - Activities• Investigation of Hat Factory Building and Property• Phase 2 Activities
• Soil sampling at surface and at depth
• Installation and sampling of groundwater monitoring wells
• Sampling of on-site septic tanks and dumps on hat factory property
15
Phase 2 - Conclusions• Soil contamination is generally within the property
boundary of the hat factory• Majority of soil contamination is underneath and in the
immediate vicinity of the building• Soil contamination is migrating to groundwater• PCE contamination in the shallow groundwater above
the MCL of 5 ppb is generally within 500 feet of site property and laterally stable
• PCE contamination in the deep groundwater, as sampled through City Well #3 appears stable
16
Phase 3 - Activities• Sampling to support Baseline Risk Assessment• Phase 3 Activities
• Additional soil sampling at surface and at depth
• Sampling of Vienna water distribution system• Vapor Intrusion Assessment
17
Phase 3 - Conclusions• Surface soil exceeds risk levels for PCE, PAHs
and metals• PCE contamination in groundwater pose risk to
human health, if not treated• City of Vienna’s treatment system eliminates PCE
contamination and public drinking water is safe• Vapor intrusion pathway is not impacting area
residents• Overall ecological risks are negligible
18
Feasibility Study19
PRP Search/ Involvement
Community Involvement
Integrated Assessment (Rerroval & Rerredial)
To Removal Program if Necessary
Feasibility Study• Establish cleanup goals• Develop general response actions• Identify potential technology types• Evaluate options on the basis of nine factors • Analyze the alternatives
20
Proposed Plan21
PRP Search/Involvement Community Involvement
Integrated Assessment (Rerroval & Rerredol)
Proposed Plan• Reason for tonight’s Public Meeting• A Proposed Plan informs the public about the
preferred cleanup option• The public reviews and comments on the
Proposed Plan, either in writing or at the Public Meeting
• All relevant documents are maintained in the publicly available documents section of the Site Profile web page
22
Remedial Alternatives• Soil Alternatives
• Soil Alternative 1 - “No Action” Alternative• Soil Alternative 2 - Soil cap• Soil Alternative 3 - Excavation and off-site
disposal• Soil Alternative 4 - Excavation and on-site
treatment
23
• Groundwater (GW) Alternatives• GW Alternative 1 - “No Action” Alternative• GW Alternative 2 - Hydraulic containment in the
shallow and deep aquifer• GW Alternative 3 - GET for the shallow aquifer
and hydraulic containment for the deep aquifer• GW Alternative 4 - GET for the shallow and deep
aquifer
24
Remedial Alternatives
Nine Evaluation Criteria• Threshold Criteria
• Overall protection of human health and environment• Compliance with ARARs
• Balancing Criteria • Long-term effectiveness and permanence• Reduction of toxicity, mobility, or volume through treatment• Short-term effectiveness• Implementability• Cost
• Modifying Criteria• State acceptance• Community acceptance
25
Soil Alternative 1 No Action
• Evaluation required by the NCP• Serves as a baseline to compare with other
alternatives• Does not meet threshold criteria
26
Soil Alternative 2Soil Cap
• Facility, along with foundation, would be demolished and removed
• Surface soil would be removed• Subsurface soil contamination would be covered with a
low permeability material (cover is not an engineered RCRA cap)
• Positives: Lower capital costs than excavation• Drawbacks: Soil would be left in place, with O&M
activities to ensure integrity of cover
27
Soil Alternative 2Soil Cap
28
Soil Alternative 3Excavation and Off-Site Disposal
• Facility, along with foundation, would be demolished and removed
• Soil contamination would be excavated and shipped off to an off-site hazardous waste landfill
• Positives: Contamination removed from system; soil no longer a source to groundwater, and no long-term O&M
• Drawbacks: Truck traffic and higher relative capital costs
29
30Soil Alternative 3Excavation and Off-Site Disposal
Soil Alternative 4Excavation and On-Site Treatment
• Facility, along with foundation, would be demolished and removed
• Soil contamination would be excavated and treated by an on-site thermal desorption unit
• Treated soil would be used to backfill excavation• Positives: Soil no longer a source to groundwater, no
off-site disposal, and no long-term O&M• Drawbacks: Operation of on-site thermal desorption unit
may be difficult to implement, due to lack of electricity and other site conditions and higher relative capital costs
31
32Soil Alternative 4Excavation and On-Site Treatment
Preferred Soil Alternative
• Preferred Soil Alternative:• Soil Alternative 3 – Excavation and Off-Site
Disposal
33
Groundwater (GW) Alternative 1 No Action
• Evaluation required by the NCP• Serves as a baseline to compare with other
alternatives• Does not meet threshold criteria
34
Groundwater (GW) Alternative 2 Hydraulic Containment inShallow and Deep Aquifer
• Low-flow wells to address shallow contamination • Deep groundwater (GW) plume would continue to be treated
by Well #3
• Positives: Would capture shallow aquifer and prevent downward migration; City Well #3 would not be impacted by pumping rates of GETS and use of existing infrastructure
• Drawbacks: O&M of both shallow extraction wells and city’s treatment system, and longer cleanup time frame
35
Groundwater (GW) Alternative 2Hydraulic Containment in Shallow and Deep Aquifer
36
Groundwater (GW) Alternative 3GET for Shallow Aquifer and
Hydraulic Containment for Deep Aquifer
• Shallow groundwater would be treated similarly to GW Alternative 2
• Deep groundwater plume would continue to be treated by Well #3
• Positives: Shorter cleanup time frame than GW Alternative 2
• Drawbacks: O&M of both shallow extraction wells and city’s treatment system
37
Groundwater (GW) Alternative 3GET for Shallow Aquifer and
Hydraulic Containment for Deep Aquifer38
Groundwater (GW) Alternative 4GET for Shallow and Deep Aquifer
• Shallow groundwater would be treated the same as GW Alternative 3
• Deep groundwater plume would be treated with deep extraction wells
• Positives: Shorter cleanup time frame than GW Alternatives 2 and 3
• Drawbacks: O&M of both shallow and deep extraction wells; may not be implementable because volume of groundwater extracted may be too high
39
Groundwater (GW) Alternative 4GET for Shallow and Deep Aquifer
40
Groundwater (GW) Alternative 4GET for Shallow and Deep Aquifer
41
Preferred Groundwater Alternative
• Preferred Groundwater Alternative:• GW Alternative 3 – GET for Shallow Aquifer
and Hydraulic Containment for Deep Aquifer
42
Preferred Alternatives• Preferred Soil Alternative:
• Soil Alternative 3 – Excavation and Off-Site Disposal
• Preferred Groundwater Alternative:• GW Alternative 3 – GET for Shallow Aquifer
and Hydraulic Containment for Deep Aquifer
43
Public Comment Period• Mandatory 30-day comment period that began on June
22, 2017, and ends on July 22, 2017• A 30-day extension may be granted upon request• Comments may be submitted in different forms, including
electronic and through traditional mail
• Comments may be provided during meeting
44
Responsive Summary• EPA will respond to all substantive comments• Preferred Alternative may be modified as a result
of public comments• A Responsiveness Summary will be part of the
Record of Decision
45
Record of Decision46
PRP Search/Involvement Community Involvement
Integrated Assessment (Rerroval & Rerredol)
To Removal Program if Necessary
Record of Decision• A final decision on the cleanup (Record of
Decision) is released, which includes cleanup goals, significant changes to the proposed remedy (if any), possible hazardous substances remaining on the site, further analysis and review, and appropriate time frame.
47
Public Comment PeriodJune 22 to July 22, 2017
Administrative record file available for review online at:
https://semspub.epa.gov/src/collections/07/SC32109
OR
U.S. EPA Region 7Records Center
11201 Renner Blvd.Lenexa, KS 66219
For additional information, visit:www.epa.gov/superfund/viennawells
48
Contact InformationPublic comments may be submitted to:
Hoai TranProject Manager
U.S. EPA Region 7
11201 Renner Blvd.
Lenexa, KS 66219
Phone: 913-551-7330
Toll-free: 800-223-0425
Email: tran.hoai@epa.gov
Elizabeth KramerCommunity Engagement Specialist
U.S. EPA Region 7
11201 Renner Blvd.
Lenexa, KS 66219
Phone: 913-551-7186
Toll-free: 800-223-0425
Email: kramer.elizabeth@epa.gov
49
Comments and Questions?
50
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