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Zoo 1
INTRODUCTION ^
Meeting Objectives:
Q Begin dialogue with the community regarding cleanup alternatives
Q Review the site schedule
Q Present the Alternatives Analysis Report
Q Answer Questions
o <r-
Page 1 of 44 C>o
INTRODUCTION
Key Points:
> Draft Report, your comments will be considered
> Historical resources and associated impacts are major parameters in evaluating options
> Community impacts are important factors
> Integration of cleanup with historic preservation and long-term land use consistent with land ownership/ community vision is the objective
Page 2 of 44
INTRODUCTION Site Contacts USEPA toll free number 1-888-372-7341
Project Managers for EPA:
Edward Hathaway ME/VT/CT Superfund Section 1 Congress Street Suite 1100, mailcode: HBT Boston, MA 02114-2023 Phone: (617) 918-1372, or 1-888-372-7341, ext. 81372 Fax:(617)918-1291 E-mail: [email protected]
William Lovely ME/VT/CT Superfund Section 1 Congress Street Suite 1100, mailcode: HBT Boston, MA 02114-2023 Phone: (617) 918-1240, or 1-888-372-7341, ext. 81240 Fax:(617)918-1291 E-mail: [email protected]
Community Involvement Coordinator:
Sarah White 1 Congress Street Suite 1100, mailcode: RAA Boston, MA 02114-2023 Phone: (617) 918-1026, or 1-888-372-7341, ext. 81026 Fax:(617)918-1029 E-mail: [email protected]
EPA NEW ENGLAND WEB SITE: http://www.epa.gov/regionO 1 add: "/remed" after "regionOl" for the Superfund web site
Page 3 of 44
INTRODUCTION Site Contacts
US Army Corps of Engineers (USAGE) Project Manager:
Scott Acone 696 Virginia Road Concord, MA 01742-2751 Phone:(978)318-8162 Fax:(978)318-8064 E-mail: [email protected]
State of Vermont:
Vermont Project Manager:
Michael Young Waste Management Division 103 South Main Street/West Building Waterbury, VT 05671-0404 Phone:(802)241-3887 Fax:(802)241-3296 E-mail: [email protected]
State Historic Preservation Office Representative:
Giovanna Peebles, State Archeologist
Division for Historic Preservation
National Life Building,
Drawer 20
Montpelier, VT 05620-0501
phone: (802) 828-3050FAX: (802) 828-3206
email: [email protected]
Page 4 of 44
INTRODUCTION
How we reached this point:
a VT ANR requested EPA involvement in 1999
Q EPA presented proposal for early cleanup in February 2000
U Community response indicated that a program with substantial community involvement was preferred
G Community Advisory Group (CAG) formed as focal point for EPA and VTANR contact
Q Monthly meetings with CAG and subcommittees has resulted in a revised program
Page 5 of 44
INTRODUCTION
Current Program:
Q Implement an early cleanup to address the tailings piles
U Perform comprehensive study of site at the same time as the early cleanup
G Meet with CAG to provide regular updates
Page 6 of 44
INTRODUCTION
Current Program:
Q Better define historic resources and future use potential of the site
U Prepare a series of reports to allow for substantial public involvement
Q Four draft reports to be submitted to CAG
> Site Conditions Report; > Alternatives Analysis Report; > Supplemental Historical Report: Historical
Context and Preliminary Resource Evaluation; and > Human Health and Ecological Screening Report
Page 7 of 44
INTRODUCTION Early Cleanup Schedule
Activity
Site Conditions Report
Alternatives Analysis Report
Alternatives Analysis Presentation
Supplemental Historic Report
Supplemental Historic Report Presentation
Alternative Analysis, Historic Resources, and Future Use Discussion
Human Health and Ecological Screening Risk Assessment
Human Health and Ecological Risk Presentation
Work Plan for Field Investigations
Draft EE/CA
Final EE/CA
30 day comment on Proposed Action Public Comment
Action Memorandum
Design Removal Action
Begin Implementation
Planned Date
February 2001
March/April 2001
April 25th CAG
May 23rd 2001
May 23rd CAG
June 27th CAG
June/July 2001
July or August CAG meeting
June/July 2001
August/ September 2001
October/ November 2001
November 2001
December 2001
January 2002 - March 2003
Spring 2003
Page 8 of 44
BACKGROUND
Historical Significance:
> Many important individuals associated with the mine
> Elizabeth Mine landscape constitutes one of the largest and most intact historic mining sites in New England
> Elizabeth Mine embodies the distinctive landscape of an early nineteenth century to mid-twentieth century American metallic ore mining and processing site
> Elizabeth Mine also has archaeological potential
> Supplemental Historical Report: Historical Context and Preliminary Resource Evaluation will provide a summary of historical significance
May 23 presentation to the C AG of the historic report
Page 9 of 44
BACKGROUND
Historical Significance:
> EPA has determined the Elizabeth Mine to be eligible for the National Register of Historic Places
> State Historic Preservation Officer concurs with the EPA determination
> Section 106 of the National Historic Preservation Act will apply to the cleanup of the Elizabeth Mine
> A Memorandum of Agreement describing mitigation of adverse effects will be developed
Page 10 of 44
BACKGROUND
Previous Investigations:
Chemical Analysis Data
G Vermont Agency of Natural Resources 1977,1998
Q United Stated Army Corp of Engineers 1984
Q Colorado School of Mines 1983
Q United States Geological Survey 1998
Q Elizabeth Mine Study Group 1999
a Thayer Design Team 2000 Report
Page 11 of 44
BACKGROUND
Previous Investigations:
Biological Assessment Data
G Vermont Agency of Natural Resources Benthic Surveys 1986,1987,1998
Q United States Army Corp of Engineers 1990 Fish Survey
a Elizabeth Mine Study Group Benthic Surveys 1998, 1999
Page 12 of 44
EPA INVESTIGATIONS
Focus of investigations performed to date has been:
> Verification of previous findings
> Delineation of source areas
> Better definition of human health issues
> Improved understanding of historic resources
> Ecological impact assessment
Page 13 of 44
EPA INVESTIGATIONS
Sampling of:
> Tailings Piles 1, 2, and 3
> Residential water supplies
> Residential soil, dust, and air
> Surface water and sediments of Copperas Brook, West Branch of the Ompompanoosuc, East Branch of the Ompompanoosuc, Ompompanoosuc, Lord Brook, and, several other tributaries to the West Branch
Biota surveys and toxicity testing were performed to provide additional measures of the ecological impact
Page 14 of 44
EPA INVESTIGATIONS
Results:
Surface Water
S Concentration of certain metals (primarily aluminum, cobalt, copper, iron, manganese, and zinc) in surface water are significantly higher in areas downgradient of the tailings
S Aluminum is consistently elevated in upstream locations, but at much lower levels than the mixing zone
S Nickel and cadmium are only elevated within Copperas Brook
S Lead and barium do not appear to be related to the tailings
Page 15 of 44
EPA INVESTIGATIONS
Results:
Surface Water
S Copperas Brook and a section of the West Branch of the Ompompanoosuc just below the confluence with Copperas Brook have the highest concentrations of metals in surface water within the study area
S Maximum concentrations in the West Branch of the Ompompanoosuc exceeded Vermont Water Quality Standards (VTWQS) by a factor of 209 for aluminum, 35 for copper, and 45 for iron
S The same section of the river failed to meet Vermont Water Quality Standards in 55 of 61 samples for aluminum, 37 of 64 for copper, and 39 of 64 for iron
Page 16 of 44
EPA INVESTIGATIONS
Results:
Human Health
One former residential well contained high concentrations of several metals including copper, cadmium, manganese, and iron
This well has been abandoned
Copper, iron, lead, and possibly thallium have been detected in residential yards and homes
A more detailed assessment of human health and ecological impacts will be presented in an upcoming report
Page 17 of 44
Frequency of Surface Water Concentrations Above Standards (Vermont Water Quality Standards and Other)
Constituent
aluminum
cadmium
cobalt
copper
iron
lead
manganese
selenium
zinc
Upstream and
Tributaries/ Reference Locations
42 samples
77%
0%
0%
9%
9%
23%
9%
0%
2%
Source Areas:
Tailings and Air
Shaft
61 samples
92%
27%
92%
84%
87%
2%
93%
24%
53%
Mixing Zone in WBOR
64 samples
86%
0%
28%
58%
61%
12%
48%
2%
3%
Below Mixing Zone in WBOR
36 samples
86%
0%
0%
44%
36% 6%
11% 3%
8%
Ompompanoosuc
River
11 samples
82%
0%
0%
36%
10% 10%
27%
0%
0%
Page 18 of 44
EPA INVESTIGATIONS
Preliminary Conclusions from Investigations:
S TP1, TP2, and TP3 are the major source areas for acid mine drainage and metal loading to the West Branch of the Ompompanoosuc
S Tailings represent an estimated 84% of metal (Al, Cu, Fe, Zn) loading to the West Branch of the Ompompanoosuc during baseline flow (approximately 97% of the loading during peak flow events)
S The South Open Cut and Air Shaft are less significant sources of contaminants than the tailings
S North Open Cut is not a source area
S The tailings are having a negative impact on the West Branch, as demonstrated by failure of the river to meet VTWQS
Page 19 of 44
EARLY CLEANUP
Concept:
U Implement a cleanup action for the tailings while a long-term investigation is under way
Q Control primary source areas as early as possible
Page 20 of 44
EARLY CLEANUP
Process:
01 EPA Non-Time-Critical Removal Action (NTCRA) Authority
Q Cleanup options are described in an Engineering Evaluation and Cost Analysis (EE/CA)
Q EE/CA and proposal for early cleanup are subject to public comment
Q EPA signs a decision document known as an Action Memorandum to formally initiate an early cleanup
Q Design and Implementation occur after the Action Memorandum
Page 21 of 44
EARLY CLEANUP
Modified Process:
Q Draft Reports prepared to preview sections of the EE/CA and to highlight critical subject areas (historic preservation)
Q Alternative Analysis Report developed to allow for early public involvement in cleanup option development
Q The Alternative Analysis Report evaluates cleanup options and recommends a short list of alternatives
Q The Alternatives Report is a draft that is intended to serve as the basis for dialogue between EPA, VT ANR, the State Historic Preservation Office, the community, and other interested parties
Page 22 of 44
ALTERNATIVES ANALYSIS REPORT
Objectives of the Early Cleanup:
Q Achieve VT Water Quality Standards in the West Branch of the Ompompanoosuc
O Minimize and/or prevent the formation of acid mine drainage
Q Stabilize the slopes of the tailings to reduce erosion and prevent a future slope failure
Q Comply with requirements of National Historic Preservation Act by avoiding impacts to historic properties to the extent practical, and providing mitigation for any unavoidable adverse effects
Q Comply with all applicable federal and state regulations
Page 23 of 44
ALTERNATIVES ANALYSIS REPORT
Important Site Characteristics:
Q Copperas Brook is located in a steep drainage with a wide fluctuation in flows (2 gallons per minute to over 1,000 gallons per minute)
Q The stability of the existing slopes of TP1 and TP2 is marginal
Q Site topography and historic resources limit the amount of space available for the cleanup
Q Unweathered tailings within the Tailings Piles have a high acid generating potential
G Historic resources need to the protected
Page 24 of 44
ALTERNATIVES ANALYSIS REPORT
General Cleanup Approaches:
Three basic approaches to address acid mine drainage:
1. Prevent water from coming into contact with acid generating material
2. Keep acid generating material saturated in low oxygen environment
3. Capture and treat all of the acid mine drainage
Page 25 of 44
ALTERNATIVES ANALYSIS REPORT
General Cleanup Options Evaluation:
Numerous technologies evaluated (over 20 individual technologies)
Some technologies were not determined to be appropriate as stand-alone solutions but may be used as components of several cleanup strategies
A short list of cleanup options was developed for further evaluation in the Engineering Evaluation and Cost Analysis (EE/CA)
Page 26 of 44
ALTERNATIVES ANALYSIS REPORT
Cleanup Options Evaluated in the Alternatives Report:
Cleanup Option 1: Collect and Treat
Cleanup Option 2: Hydraulic Isolation (3 sub-options)
Cleanup Option 3: Soil Cover
Cleanup Option 4: Wet Cover
Page 27 of 44
ALTERNATIVES ANALYSIS REPORT
Cleanup Option 1: Collect and Treat
Summary: Capture all water that comes into contact with the tailings and treat this water in a standard water treatment plant
Major Components:
> Surface water collection system to divert clean water away from tailings
> Surface water collection to capture water that contacts tailings
> Collection of the seep water at the base of TP 1
> Storage of water in a holding pond to stabilize flow into the treatment plant
> Treatment Plant
> Stabilization of steep banks (possibly using a concrete surface)
Estimated Capital Costs: $11,400,000
Estimated Operation and Maintenance Cost: $2,500,000 per year
Page 28 of 44
ALTERNATIVES ANALYSIS REPORT
Cleanup Option 2: Hydraulic Isolation
Summary: This cleanup approach uses a combination of engineering controls to minimize the water that comes into contact with the tailings as well as natural systems/passive treatment approach to treat any remaining water that comes into contact with the tailings
Three sub-options have been developed
Page 29 of 44
ALTERNATIVES ANALYSIS REPORT
Option 2A: Hydraulic Isolation with consolidation of TP2 and TP3 onto TP 1.
Major Components:
> Removal of all tailings from TP2 and TP3 and placement of this material on TP1 to create the smallest possible area for long-term management
> Grade the slope of TP1 to a 3:1 surface
> Divert all surface water from area outside TP1 around the perimeter
> Cover the tailings in TP1 with a multi-layer cap to prevent infiltration
> Install a collection system, or toe drain, along the base of TP1 to collect any water that continues to flow through the tailings
> Treat the water from the seeps of TP 1 using a natural systems/ passive treatment approach
Estimated Capital Costs: $20,600,000
Estimated Operation and Maintenance costs: $21,500 per year with a periodic costs every 15 years of approximately $341,000
Page 30 of 44
ALTERNATIVES ANALYSIS REPORT
Option 2B: Hydraulic Isolation with consolidation of all of TP 2 and a portion of TP3 onto TP1, and preservation of a portion of the heap leaching piles (TP3)
Major Components same as 2A except:
> Preserve some portion of TP3
> Treat the flow of water from the preserved portions of TP3 with a natural systems passive treatment approach
Estimated Capital Costs: $21,000,000
Estimated Operation and Maintenance costs: $24,800 per year with a periodic costs every 15 years of approximately $625,000
Page 31 of 44
ALTERNATIVES ANALYSIS REPORT
Option 2C: Hydraulic Isolation with consolidation of a portion of TP3 and a portion of TP 2 onto TP1 and preservation of a portion of the heap leaching piles (TP3).
Major Components same as 2B except:
> Removal of only a portion of TP 2 with placement of this material on TP1
> Install an engineered surface to stabilize the slopes of TP1 and TP2 in the current configuration
> Roller compacted concrete is a likely material for the slope stabilization
> Treat the flow of water from the seeps of TP1 and the remaining area of TP3 with a natural systems/passive treatment approach
Estimated Capital Costs: $21,000,000
Estimated Operation and Maintenance costs: $26,200 per year with a periodic costs every 15 years of approximately $632,000
Page 32 of 44
ALTERNATIVES ANALYSIS REPORT
Cleanup Option 3: Soil Cover
Summary: This option is very similar to cleanup option 2 except that a soil cover which does not limit infiltration is placed over the tailings.
Major Components:
> Removal of all of TP 2 and TP3 and placement of this material onTPl
> Grade slopes to 4:1
> Divert all surface water outside of TP1 around the perimeter
> Cover the tailings on the graded surface of TP1 and TP2 with a soil cover of 24 inches to develop vegetation
> Install a collection system, or toe drain, along the base of TP1 to collect any water that continues to flow from the tailings
> Treat the remaining flow of water from the seeps of TP1 and the remaining area of TP3 with a natural systems/passive treatment approach
Estimated Capital Costs: $17,000,000
Estimated Operation and Maintenance costs: $28,600 per year with a periodic costs every 10 years of approximately $771,000
Page 33 of 44
ALTERNATIVES ANALYSIS REPORT
Cleanup Option 4: Wet Soil Cover
Summary: This option relies upon the saturation of the tailings along with the delivery of low oxygen high dissolved organic carbon water into the tailings to limit acid generation.
Major Components:
> Removal of a portion TP3 and placement of this material on TP1
> Grade the slopes to a stable configuration of 5:1
> Divert all surface water from area outside TP1 around the perimeter
> Cover the tailings on the graded surface of TP1 and TP2 with a series of fens/wetlands
> Install a collection system, or toe drain, along the base of TP1 to collect any water that continues to flow from the tailings
> Treat the remaining flow of water from the seep of TP1 and the remaining area of TP3 with a natural systems passive treatment approach
Estimated Capital Costs: $22,300,000
Estimated Operation and Maintenance costs: $30,800 per year for the first 5 years then $15,400 per year. Periodic costs every 5 years of $244,700, and every 15 years of approximately $531,000
Page 34 of 44
ADVANTAGES AND DISADVANTAGES
Alternative 1: Collect and Treat Runoff
Advantages
> Least impact on historic resources > Minimizes construction traffic > Lowest construction costs
Disadvantages
> High cost of maintenance (PRSC) that will be borne by the State of Vermont
> The treatment plant would generate a large quantity of potentially hazardous wastes
> Does not control the source of AMD; therefore AMD generation will continue
Page 35 of 44
ADVANTAGES AND DISADVANTAGES
Alternative 2: Hydraulic Isolation
Option 2A: Combine TP-1/2/3, Regrade, and Hydraulic Isolation
Advantages
>
>
Significantly reduces or eliminates acid-generation potential
Provides for future beneficial reuse of land >>
Utilizes innovative technologies for treatment of seep water Minimizes long-term costs borne by the State of Vermont
(PRSC costs)
Disadvantages
> Permanent, irreversible impact to industrial landscape of all tailings features, including complete removal of TP3
> Significant exposure of un-oxidized tailings during construction
> Impacts to Mine Road residents, including noise, dust, traffic
> Significant construction traffic for surrounding towns
Page 36 of 44
ADVANTAGES AND DISADVANTAGES
Option 2B: Same As 2A, But Retains Portion ofTP-3
Advantages
> Significantly reduces or eliminates acid-generation potential
> Provides for future beneficial reuse of land > Utilizes innovative technologies for treatment of seep water > Minimizes long-term costs borne by the State of Vermont
(PRSC costs) > Flows from TP1 may eventually be reduced below levels
requiring treatment > Retains portion of historic copperas production area
Disadvantages
> Permanent, irreversible impact to industrial landscape of all tailings features, including partial removal of TP3
> Significant exposure of un-oxidized tailings during construction
> Impacts to Mine Road residents, including noise, dust, traffic
> Significant construction traffic for surrounding towns > Additional cost to treat water from remainder of TP3 in
perpetuity
Page 37 of 44
ADVANTAGES AND DISADVANTAGES
Option 2C: Same As 2B, But Retains TP-1 and TP-2 Profile
Advantages
> Significantly reduces or eliminates acid-generation potential
> Provides for future beneficial reuse of land > Utilizes innovative technologies for treatment of seep water > Minimizes long-term costs borne by the State of Vermont
(PRSC costs) > Flows from TP1 may eventually be reduced below levels
requiring treatment > Retains portion of historic copperas production area > Retains overall profile and current appearance of TP1/2 > Minimizes exposure of un-oxidized tailings during
construction
Disadvantages
> Permanent, irreversible impact to industrial landscape of all tailings features, including partial removal of TP3
> Impacts to Mine Road residents, including noise, dust, traffic
> Significant construction traffic for surrounding towns > Additional cost to treat water from remainder of TP3 in
perpetuity
Page 38 of 44
ADVANTAGES AND DISADVANTAGES
Alternative 3: Soil Cover
Advantages
> Provides for future beneficial reuse of covered tailings > Utilizes innovative technologies for treatment of seep water > Lower cost than impermeable caps > Less truck traffic alternative 2
Disadvantages
> Does not eliminate interaction of tailings with water and oxygen; therefore allows continued acid production
> Permanent, irreversible impact to industrial landscape (TP 1,2, and 3)
> More material movement than any of Alternative 2 sub-options
> Significant exposure of un-oxidized tailings during construction
> Impacts to Mine Road residents, including noise, dust, traffic
> Significant construction traffic for surrounding towns > Perpetual maintenance costs
Page 39 of 44
ADVANTAGES AND DISADVANTAGES
Alternative 4: Wet Cover Approach
Advantages
> If successful would reduce AMD production using naturally generated materials
> Promotes most biodiversity of all options
Disadvantages
> Oxygen may continue to infiltrate into tailings (except below and around fens) allowing continued acid generation
> Complete saturation of the tailings during substantial periods of the year may not be possible
> Storage of water on top of TP1 and TP2 substantially increases slope instability
> Significant impact to industrial landscape (TP1, 2) > Most material movement of all cleanup options > Most significant exposure of un-oxidized tailings during
construction of all options > Impacts to Mine Road residents, including noise, dust,
traffic > Significant construction traffic for surrounding towns > Perpetual maintenance may be required
Page 40 of 44
ALTERNATIVES EVALUATION SUMMARY
Cleanup Options
Lower Capital Costs
Lower Maintenance Costs
Proven Technology
Reliable/Long-Term Effectiveness
Least Adverse Effect on Historic Properties
Minimize Truck Traffic
Maximize Re-Use Potential
Minimize Exposure of Un-Oxidized Tailings
Promotes Biodiversity
1 2A 2B 2C 3 4
+ + / /
y / y y
/ / /
+ / y
+ y
^ / /
+ y
y ^ ^
y +
+ Indicates that this option is substantially better than the others for this category Indicates that this criterion is a strength for this option
Page 41 of 44
SUMMARY
The community's input is requested:
G The current list of cleanup alternatives is based upon the technical evaluation by EPA and its consultants
Q EPA is seeking public comment regarding the range of alternatives to be considered in the Engineering Evaluation and Cost Analysis (EE/CA)
Q The list of alternatives may change based on comments
Q EPA is also seeking public comment regarding the alternatives' impacts to the community and to historic resources
Page 42 of 44
NEXT STEPS
Q Dialogue regarding Alternatives Report
Q Comments should be sent to EPA by the end of May 2001
Ul Presentation of historic report at May 23 CAG meeting
Q Subcommittee meetings to discuss alternatives and historic reports should be scheduled
Page 43 of 44
NEXT STEPS
Target June C AG for discussion of both Alternatives and Historic Reports
Set a schedule for regular meetings to discuss future land use and landowner issues
Community input regarding possible future use of the site will be needed by the end of July 2001 to be considered in EE/CA
A National Historic Preservation Act 106 review will be included in May or June CAG presentation
Final Note: Many of the specific details relating to the cleanup action will be addressed as part of the design phase (truck routes, material source locations, construction sequencing, staging areas and construction road locations, exact location of treatment systems, and surface water diversion)
Page 44 of 44