epa's proposed plan at the vienna wells sitedetected in city well #1 in 1994 • preliminary...

Post on 10-Sep-2020

2 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

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

top related