OPERATIONS AND 

MAINTENANCE 

PLAN 

O’CONNOR COMPANY 

SUPERFUND SITE 

AUGUSTA, MAINE

222350 

Central Maine Power 

Company 

October 2009 woodardcurran.com

COMMITMENT & INTEGRITY DRIVE RESULTS
Central Maine Power (222350.00) i October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

TABLE OF CONTENTS 

SECTION PAGE NO. 

1. INTRODUCTION................................................................................................................................ 1-1

1.1 Site Setting .....................................................................................................................................1-1

1.2 History of Contamination and Remediation ....................................................................................1-2

1.3 Current Conditions..........................................................................................................................1-5

1.4 Purpose of the Operations and Maintenance Plan.........................................................................1-7

2. RECORD KEEPING AND REPORTING............................................................................................ 2-1

3. NORMAL OPERATIONS AND MAINTENANCE ............................................................................... 3-1

3.1 Inspections .....................................................................................................................................3-1

3.2 Soil Sampling .................................................................................................................................3-1

3.3 Routine Maintenance......................................................................................................................3-2

3.4 Repairs ...........................................................................................................................................3-4

4. ASSESSMENT OF SITE CONDITIONS............................................................................................. 4-1

5. OPERATIONAL SAFETY PLAN........................................................................................................ 5-1

6. GLOSSARY OF ACRONYMS............................................................................................................ 6-1

7. REFERENCE LIST............................................................................................................................. 7-1

LIST OF FIGURES 

FIGURE PAGE NO. 

Figure 1 Site Location Map.......................................................................................................................... 1-3

Figure 2 Site Features ................................................................................................................................. 1-4

Figure 3 Revised Site Plan .......................................................................................................................... 1-6

Figure 4 Designated Area Soil Sampling Locations .................................................................................... 3-3

APPENDICES 

Appendix A: 2009 Site Photographs

Appendix B: O’Connor Inspection Checklist

Appendix C: Monitoring Well Decommissioning Procedures
Central Maine Power (222350.00) 1-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

1. INTRODUCTION 

1.1 SITE SETTING 

The F. O’Connor Site (Site) consists of approximately 23 acres within a 28-acre property owned by Central Maine 

Power Company (CMP) and is located on U.S. Route 17 approximately three miles east of the Kennebec River in 

Augusta, Maine. The location of the property is shown on Figure 1 and the Site features are shown on Figure 2. The 

surrounding area is generally rural. The property is bordered on the east and southeast by Riggs Brook, a small 

northerly flowing tributary of the Kennebec River, on the north and west by woodlands, and on the south by Route 17. 

The property south of Route 17 is generally wooded. A residence abuts the CMP property along its western 

boundary. The land at the Site was used as farmland until the 1950s when the F. O’Connor Company established a 

salvage yard and transformer recycling operation at the Site. The Maine Department of Environmental Protection 

(MEDEP)-designated Hazardous Substance Site consists of the same 23 acres within the 28-acre property. 

The Site is located on a ridge that transects the Site in a generally northeast-southwest direction. An access road 

splits the Site from southwest to northeast. North and west of the road, the Site is relatively level, with a low swampy 

area known as the Upland Marsh. East and south of the road the topography slopes sharply toward Riggs Brook, 

with a change in elevation of approximately 50 feet. Three water bodies are located on the Site, all of which were 

created by operations of the F. O’Connor Company and later reconstructed as a part of the source control work. The 

approximately 2-acre Upland Marsh drains to a channel that flows to the Upper and Lower Lagoons and on to the 

Riggs Brook wetlands. Figure 2 shows these features and site topography. 

The overburden soils at the Site generally consist, from surface to depth, of glacial marine silts and clays, glacial till, 

and bedrock. The clay tends to be absent only in areas of shallow bedrock. Bedrock drilling completed during site 

investigations indicated mostly competent rock with very few recognizable fractures. Bedrock outcrops are found in 

the areas of transformer work area (TWA) I and III (see Figure 2). 

The principal groundwater migration pathway on the Site is a discrete zone within the till along the top of the bedrock 

surface. Groundwater flow from the Upland Marsh (a large recharge basin) is confined and channeled through the 

bedrock trough in the bedrock saddle centered immediately northeast of the Upper Lagoon. The bedrock flow regime 

has very little water in storage. The vertical permeability of the bedrock is believed to be very low, creating a “quasi” 

perched condition of the overburden groundwater flow system. At the southeastern end of the Site, near Riggs 

Brook, the potentiometric surface of the bedrock groundwater is above the ground surface. MW-106B in this area is 

a free-flowing artesian well. 
Central Maine Power (222350.00) 1-2 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

1.2 HISTORY OF CONTAMINATION AND REMEDIATION 

The F. O’Connor Company operated a salvage yard for the dismantling and recycling of electrical transformers and 

capacitors on the Site from the early 1950s until the late 1970s. This resulted in drippage and spillage of oil to the 

ground, principally in the vicinity of the TWAs. Soil and groundwater contamination primarily consisted of 

polychlorinated biphenyls (PCBs) with some volatile organic compounds (VOCs) and semi-volatile organic 

compounds (SVOCs), and inorganics. Potential sources of contamination that were identified on the Site included 

three TWAs, scrap piles, oil storage tanks, and two lagoons installed to help control oil migration from the Site (see 

Figure 2). 

In September 1991, CMP, an identified potentially responsible party (PRP) at the Site, signed a Consent Order with 

the United States Environmental Protection Agency (USEPA) to undertake an investigation and remediation of the 

Site. CMP also acquired ownership of the Site from the F. O’Connor Company in 1992. 

The Remedy for the Site was initially described in the Record of Decision (ROD) (USEPA, 9/89) and Consent Decree 

(USEPA, 9/3/91), and was modified in the Explanation of Significant Differences (ESD) (USEPA, 7/20/94). The 

Remedy included two components, Source Control (SC) and Management of Migration (MOM). On April 26, 1996 

USEPA separated the Riggs Brook component of the MOM by creating a third operable unit (OU-3). The Site was 

therefore broken down into three operable units: 

• OU-1 Source Control 

• OU-2 Management of Migration 

• OU-3 Riggs Brook 
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JOB NO: 222350.01 

DATE: OCTOBER 2009 

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SUPERFUND SITE BOUNDARY 

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FIGURE2 
Central Maine Power (222350.00) 1-5 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

The Source Control Remedial Action (SCRA) at OU-1 was completed in November 1997, and included the 

excavation and off-site disposal of 20,000 tons of soil and sediment with PCB concentrations greater than 10 parts 

per million (ppm). Another 3,000 tons, with PCB levels less than 10 ppm, were consolidated on site in one three- to 

four-acre area, identified as the Designated Area (See Figure 2). Approximately 24,000 cubic yards of clean soil 

(PCBs less than 1 ppm) were imported to the Site to restore the excavated area to approximate the original grade 

and to provide a 12-inch soil cover over the entire Designated Area. Site restoration also included re-establishing 

drainage patterns to achieve discharges to Riggs Brook similar to those that existed prior to remediation of the Site, 

restoration of on-site wetlands, including the establishment of compensatory wetlands, and removal of the perimeter 

fence (W&C, 1998). 

The Amendment to the Consent Decree, September 2003 and its Appendix II Remedial Design/Remedial Action 

(RD/RA) 2003 Statement of Work (SOW) (USEPA, 9/18/03) required that the 25-sided Designated Area be simplified 

to a 10-sided area. This 10-sided Designated Area has been surveyed and permanent markers have been placed on 

site to make the Designated Area easier to recognize while in the field. The current site topography following the 

SCRA as well as the Revised 10-sided Designated Area is shown on Figure 2. 

The MOM operable unit (OU-2) addresses groundwater quality and the potential migration of contaminants on the 

Site. Groundwater at the Site has been monitored since 1996, and a number of monitoring wells on the Site continue 

to be sampled for groundwater quality. The 1989 ROD was amended in September 2002 following an evaluation of 

the technical practicability of restoring the groundwater within a reasonable time period. The ROD Amendment 

(USEPA, 9/02) changed the remedy for groundwater and designated a Technical Impracticability (TI) zone for OU-2. 

The TI zone for OU-2 is shown on Figure 3. 

The Riggs Brook operable unit (OU-3) addresses sediment and biota quality along Riggs Brook. In accordance with 

the 1989 ROD and the 1991 SOW, ten years (1996-2005) of annual sediment sampling have been completed and 

biota sampling, also required by the ROD, was completed in 1997 and 2000. 

1.3 CURRENT CONDITIONS 

Based on the five-year site review completed in September 2007, the Site remains a mix of forest and open field, 

bordering the Riggs Brook wetland, and unchanged since the 2002 five-year review. The open fields encompass the 

formerly contaminated areas and the three reconstructed wetlands on the Site (Upland Marsh, Upper Lagoon, and 

Lower Lagoon). The Site is not actively used by CMP. Surrounding land uses include low-density residential, light 

agricultural, fields, and forest. 
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BY EPRO 2002 

- ·-·-·-·-·-REVISED 10-SIDED DESIGNATED AREA 

SUPERFUND SITE BOUNDARY 

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TOPOGRAPHIC INFORMATION IS APPROXIMATE. 

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COMPILED FROM ORIGINAL SITE PLAN AND 

1999 SURVEY OF REMEDIATED AREA 

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Central Maine Power (222350.00) 1-7 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

Natural resources on the Site include both terrestrial and aquatic habitats. Riggs Brook is not navigable in the vicinity 

of the Site, but large wetland areas in the Riggs Brook watershed have been mapped by the MEDEP. The Riggs 

Brook wetlands are considered to be shrub swamps, consisting of a mix of woodlands and emergent aquatic 

vegetation and peat. 

Site inspections have concluded that vegetation at the Site is well developed, and drainage channels are in good 

condition, and functioning as designed. Annual mowing was not routinely performed in the first 10 years after Source 

Control to allow the vegetation to establish itself. However, the TWA II area was mowed to facilitate access to the 

wells. In 2006 and 2007, the entire Designated Area, with the exception of the steep slopes east of TWA II, was 

mowed. Future mowing at the Site will be conducted in accordance with this Operations and Maintenance (O&M) 

Plan. Minor ruts in the access road were filled in 2003; otherwise the access road is in good repair. A vehicle barrier 

gate across the access road was installed in 2003 (see Figure 2). 

Monitoring conducted in 2007 to evaluate wetland vegetation survival and general wetland system recovery, 

measured slightly less acreage and less vegetative cover than was recorded prior to remediation, yet the function 

and value acreage has increased. The restored wetlands have developed wet meadow communities comprised of a 

dominance of wetland species with a mixture of old-field upland species, which is consistent with the characteristics 

of natural communities. In addition to the wetland species, the 2007 monitoring identified hydric soil conditions and 

evidence of hydrology. The wetland communities provide potentially diverse habitat for aquatic and wetland 

dependant species. 

Photographs taken in 2009, showing the Site conditions and features (Upland Marsh, lagoons, access road, vehicle 

barrier gate, culverts, representative boundary markers, etc.) are located in Appendix A. 

1.4 PURPOSE OF THE OPERATIONS AND MAINTENANCE PLAN 

This O&M Plan has been prepared for Operable Units OU-1 and OU-2. Sediment and biota sampling have been 

completed at OU-3 and there is no additional monitoring proposed for OU-3. 

This O&M Plan has been prepared in accordance with the Section 4.e (6) of the Revised Statement of Work (RSOW) 

(USEPA, 10/20/94) for the Site. The purpose of this O&M Plan is to define those operations, monitoring and 

maintenance activities that will be performed to ensure the long-term continued effectiveness of the SCRA and longterm monitoring of the Site. The draft O&M Plan was originally submitted as part of the SCRA Work Plan 100 

Percent Remedial Design (CMP, 7/9/96), and has been updated several times since. The O&M plan will be reviewed 

and updated as necessary coincident with the five-year reviews. By performing Site maintenance and monitoring 
Central Maine Power (222350.00) 1-8 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

activities in a timely manner as outlined in this plan, the potential for major repairs and long-term costs will be 

reduced. 

Wetland compliance monitoring required as a part of the 100% remedial design for the SCRA was conducted five 

times between 1998 and 2007, and has been completed. 
Central Maine Power (222350.00) 2-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

2. RECORD KEEPING AND REPORTING 

The O&M activities associated with the SCRA and long-term monitoring at the Site were initiated in 1998 upon 

completion of the SCRA. Inspections of the Site have been conducted semi-annually, at the same time as the 

groundwater monitoring events. Beginning in 2008, groundwater monitoring is conducted annually in April, but site 

inspections continue to be conducted semi-annually in the spring and the fall. An inspector familiar with the Source 

Control 100 Percent Remedial Design, the O&M requirements, and the monitoring requirements will perform each 

inspection for the Site. The information from each inspection will be recorded on the inspection checklist provided in 

Appendix B, as well as any site photographs. 

Following each of the inspection visits, necessary maintenance or repairs will be scheduled and performed as 

required. The inspection checklists, along with a letter report describing any routine maintenance or repairs that were 

or will be completed will be forwarded to USEPA and MEDEP within a month of the inspection. This letter report will 

also address any non-routine maintenance or repairs that are proposed. 

The RD/RA SOW, Appendix II of the 2003 Amendment to the Consent Decree, stated that as long as contamination 

remains which prevents unrestricted use of the Site, five-year reviews shall be performed to evaluate the 

effectiveness of the implemented cleanup plan. Consequently, it is anticipated that maintenance and inspections will 

continue for an extended period of time. As part of the five-year process, the O&M Plan will be reviewed and revised 

as necessary to incorporate significant changes in the operations and maintenance procedures and frequencies. 

USEPA and MEDEP will be given the opportunity to comment on any proposed changes to the O&M Plan and 

USEPA’s concurrence, after opportunity for MEDEP review and comment, will be obtained before implementing any 

proposed changes. 

Contact names, addresses and phone numbers for reporting are as follows. 

Mr. Terrence Connelly 

USEPA Region 1 

1 Congress Street 

Suite 1100 (Mail Code HBT) 

Boston, MA 02114-2023 

(617) 918-1373 

Ms. Claudia Sait 

Maine Department of Environmental Protection 

Bureau of Remediation and Waste Management 

State House Station #17 

Augusta, ME 04333-0017 

(207) 287-7713 

Roy Koster 

Central Maine Power 

Environmental Compliance Department 

83 Edison Drive 

Augusta, ME 04336 

(207) 626-9574
Central Maine Power (222350.00) 3-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

3. NORMAL OPERATIONS AND MAINTENANCE 

Normal operations, monitoring and maintenance for the Site have consisted of and will continue to consist of Site 

inspections, soil sampling and routine maintenance and repairs to the soil cover and drainage systems when 

necessary. The purpose of the monitoring and maintenance program is to identify and correct any damage that may 

occur to the soil cover or drainage systems that could interfere with the proper functioning of these systems or the 

protectiveness of the SCRA. If damage is identified during an inspection, corrective maintenance or repairs will be 

implemented. 

3.1 INSPECTIONS 

For each inspection, the following general information and observations will be noted. 

a. Inspector(s) Name(s); 

b. Date, time, and weather conditions; 

c. Condition of monitoring wells; 

d. Observed erosion, sloughing, or settlement of surface soils within the Designated Area; 

e. Observed erosion or rutting of access road soils; 

f. Observed animal burrow holes; 

g. Condition of culverts, drainage channels, and Designated Area permanent markers; 

h. Condition of Upland Marsh, and reconstructed lagoons; and 

i. Any other obvious changes to the condition of the Site. 

Inspections will be conducted semi-annually in the spring and fall, and in the event of a major storm (such as two 

inches or more rainfall within a 24-hour period) that could produce erosion, an additional site inspection will be 

conducted. Following each of the inspection visits, necessary maintenance or repairs will be scheduled and 

performed as required. 

3.2 SOIL SAMPLING 

As a part of operations and maintenance for the Site, every five years coincident with the Comprehensive 

Environmental Response, Compensation and Liability Act (CERCLA) -required five-year reviews, samples will be 

collected of the soil cover that was placed on the Designated Area in 1997. The purpose of sampling the soil cover is 

to demonstrate that concentrations of total PCBs remain less than 1 ppm. Using the surveyed locations on the 30-
Central Maine Power (222350.00) 3-2 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

foot sampling grid that was established during the SCRA, and additional grid nodes added where necessary to fill in 

the 10-sided Designated Area, soil samples will be collected at 10 random locations, within the 10-sided Designated 

Area, to be representative of the soil cover (see Figure 4). 

The 10 random points will be marked in the field prior to sampling. A composite soil sample will be collected from 

each sampling location from a depth of approximately 8-12 inches below ground surface. The soil will be 

homogenized and the sample collected and analyzed for PCBs using Method 8082. If PCBs are found to exceed 1 

ppm, the data will be reviewed with MEDEP and USEPA to determine if additional action is required. 

A detailed discussion can be found in the O’Connor Company Superfund Site Quality Assurance Project Plan 

Amendment (W&C, 4/17/07). This QAPP Amendment will be revised for future five-year reviews. 

3.3 ROUTINE MAINTENANCE 

Mowing. Non-wetland areas of the Designated Area will be mowed as necessary during the summer months to 

prevent the growth of trees and shrubs, and the perimeter of the access road shall be mowed as necessary to 

maintain access. Based on past experience, it is expected that this mowing will occur once each summer. The need 

to increase the frequency of mowing will be determined based upon the routine inspections and the height of the 

vegetation in the early fall during annual mowing. Any trees and shrubs observed to be growing on the steep slope 

between Points C, D, E, and F of the Designated Area will be cut down individually, as mowing this slope creates a 

potential safety issue for the mower. 

Drainage. If inspections of culverts and drainage channels show evidence of debris accumulation or damage, 

activities to unclog or repair these drainage pipes and channels shall be scheduled. It is important that all drainage 

systems are operating properly in order to prevent erosion or slope failure along the lagoon dikes, resulting in 

expensive repairs and possible environmental damage. 

If normal maintenance requires the removal of sediment or debris from drainage channels, the work shall be 

performed with typical equipment used for that purpose, taking care not to damage the surface of the cover system or 

any other site features. If maintenance of the drainage channels requires excavation greater than 12 inches, the 

USEPA and MEDEP will be notified prior to the start of the maintenance activity. 

Surface Soils. The Site surfaces shall be inspected for deficiencies in the soil layer overlying the Designated Area. 

Deficiencies may be evident as excessive erosion, surface water ponding, depressions, animal burrow holes, vehicle 

ruts, or other abnormalities. Large obstructions that may restrict the movement of water (from rainfall, snowmelt, 

etc.) from migrating into and through the soil cover shall be removed. 
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LEGEND: 

PTA DESIGNATED AREA MARKERS - SURVEYED 

BY EPRO 2002 

- ·-·-·-·-·-REVISED 10-SIDED DESIGNATED AREA 

SUPERFUND SITE BOUNDARY 

NOTES: 

1. TOPOGRAPHIC INFORMATION IS APPROXIMATE. 

TOPOGRAPHIC INFORM A llON HAS BEEN COMPILED FROM 

ORIGINAL SITE PLAN AND 1999 SURVEY OF REMEDIATED AREA. 

2. FOR SIMPLIFICATION, GROUNDWATER AND OIL MONITORING 

LOCATIONS, GEOPROBE, SURFACE WATER SAMPLING LOCATIONS 

ARE NOT SHOWN ON THIS FIGURE. 

80' 

SAMPLING GRID FOR SOURCE CONTROL 

REMEDIAL ACTION (FIGURE 5 W&C SOURCE 

CONTROL REMEDIAL ACTION REPORT SEPT 

2. 1998) 

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Central Maine Power (222350.00) 3-4 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

If animal burrow holes are observed during site inspections, efforts will be made to remove the animals from the Site, 

and the burrow holes will be filled. 

Monitoring Wells. In accordance with the Management of Migration Groundwater Monitoring Program Sampling and 

Analysis Plan (SAP), Volume I of II, Revision 4 (W&C, December, 1996), the condition of monitoring wells has been 

checked during each groundwater monitoring event, and will continue to be checked during the annual April 

groundwater monitoring events. 

In summary, the monitoring and extraction wells will be observed for the following: 

• Check the well for proper identification and location; 

• Observe the well for evidence of settlement of the casing, and condition of the surface seal; 

• Calculate the percentage of well screen that is free of sediment for each well, to determine if the well 

requires rehabilitation; and 

• Check security of the well. 

Detailed procedures for well rehabilitation are described in Section 5 and Table 4 of the SAP (W&C, December, 

1996). 

Based on USEPA’s approval of CMP’s monitoring well decommissioning request (dated June 14, 2007), 18 wells and 

7 piezometers were decommissioned during the summer of 2008 (see Figure 3). Procedures for well 

decommissioning are outlined in Appendix C. 

3.4 REPAIRS 

Erosion. The most common repair will likely be erosion or vegetation damage. Eroded areas shall be filled with soil 

and seeded. A layer of mulch or an erosion control blanket shall be provided as necessary to protect these areas 

until vegetation is established. 

Drainage Ways. Erosion of the drainage channels will be repaired in a manner that will ensure long-term resistance 

to possible future erosion. These measures may include re-grading and seeding, installation of erosion control 

blankets, or construction of riprap surfaces in areas requiring more permanent slope protection. 

The operation of the outlet pipes of the Upland Marsh, Upper Lagoon, and Lower Lagoon is important in the 

establishment and long-term success of the restored wetlands. If damage to the outlet pipes of the Upland Marsh or 

lagoons occurs, repairs shall be made as soon as possible following discovery. All repair activities shall be reviewed 
Central Maine Power (222350.00) 3-5 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

and approved by a qualified engineer. The suspected cause of the damage and all work performed as part of the 

repairs will be documented in the following site inspection report. 

Surface Soils. Settlement in the Designated Area can be tolerated provided the integrity of the cover soil remains 

intact. Vegetated areas of the Designated Area that may have experienced some settlement are still considered 

protective, due to the stabilizing effect of the vegetation. However, if erosion or rutting of soil in the Designated Area 

is observed, the area must be refilled with soil and reseeded to maintain the required cover soil depth. If erosion or 

rutting on the access road is observed, the road must be repaired by filling the ruts or eroded areas such that the 

elevation of the access road remains equal to or higher than the vegetated portion of the Designated Area. This will 

ensure that the thickness of clean soil in the access road is greater than the minimum requirement over the 

Designated Area. 

Monitoring Wells. If well rehabilitation measures other than pumping out the accumulated silt as described in the 

SAP (W&C, December, 1996) are to be undertaken, USEPA and MEDEP shall be notified prior to the start of the 

work. 
Central Maine Power (222350.00) 4-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

4. ASSESSMENT OF SITE CONDITIONS 

All normal maintenance and repairs shall be conducted as necessary and included in the inspection letter report with 

an evaluation and assessment of site conditions and any observed changes at the Site. Prior to conducting any 

repairs that are determined to be major (excavation to a depth of 12 inches or greater), the USEPA and MEDEP 

would be notified. In addition, the location of any identified problems or maintenance and repair issues shall be 

shown on the figure included in Appendix B, and included with the inspection report. 

It was noted above that the groundwater monitoring program is being performed under the Management of Migration 

Groundwater Monitoring Program Sampling and Analysis Plan (SAP), Volume I of II, Revision 4 (W&C, December, 

1996). This program, whose objective is to track dissolved PCBs and VOCs, while not an O&M activity, will be 

performed at the same time as the spring site inspection and this serves as a cross-reference to that program. The 

monitoring shall be performed until it has been determined by USEPA, after opportunity for review and comment by 

MEDEP, that the groundwater in the overburden soils and in the bedrock has achieved the performance standards 

set in the 1989 ROD and 2002 ROD Amendment. 

The 1989 ROD included temporary institutional controls as a part of the overall remedy. The 1994 ESD modified this 

to make the institutional controls permanent. CMP and MEDEP signed a restrictive covenant which was recorded in 

the Kennebec County Registry of Deeds on September 13, 2002. Compliance with this covenant, while not an O&M 

activity, will be confirmed at the same time as the spring site inspection and this serves as a cross-reference to that 

covenant.
Central Maine Power (222350.00) 5-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

5. OPERATIONAL SAFETY PLAN 

All inspections and maintenance work shall be performed in conformance with the Site Health and Safety Plan (CMP, 

7/9/96), and well decommissioning shall be performed in accordance with the supplemental Health and Safety Form 

(W&C, 4/15/08). Requirements of the Occupational Safety and Health Act (OSHA) 29 CFR provide the basic safety 

requirements that shall be followed for all activities at the Site. 

Maintenance and inspection activities present many opportunities for physical injury to occur. This Site contains 

steep slopes and riprap drainage structures which could make otherwise normal activities more unpredictable and 

dangerous. Equipment use at this Site should be done with care. Wearing the proper protective clothing and sturdy 

boots and using common sense can prevent many injuries. 
Central Maine Power (222350.00) 6-1 October 27, 2009 

Operations and Maintenance Plan Woodard & Curran 

 

6. GLOSSARY OF ACRONYMS 

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act 

CMP Central Maine Power Company 

ESD Explanation of Significant Differences 

MEDEP Maine Department of Environmental Protection 

MOM Management of Migration 

O&M Operations and Maintenance 

OSHA Occupational Safety and Health Act 

OU Operable Unit 

PCBs Polychlorinated biphenyls 

ppm Parts per million 

PRP Potentially Responsible Party 

RD/RA Remedial Design/Remedial Action 

ROD Record of Decision 

RSOW Revised Statement of Work 

SAP Sampling and Analysis Plan 

SC Source Control 

SCRA Source Control Remedial Action 

SOW Statement of Work 
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SVOC Semi-volatile organic compound 

TI Technical Impracticability 

TWA Transformer Work Area 

USEPA United States Environmental Protection Agency 

VOC Volatile organic compound 
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7. REFERENCE LIST 

CMP, 1996. Source Control (SC) 100 Percent Remedial Design, O’Connor Company Superfund Site, Augusta, 

Maine; July 9, 1996. 

CMP, 6/14/2007. Letter from Ray Koster, CMP to Terrence Connelly, USEPA, RE: O’Connor Company Superfund 

Site Monitoring Well Decommissioning Request, 2007. 

TRC Engineering, LLC, 2007. Wetland Restoration Monitoring Report for the O’Connor Company Superfund Site, 

Augusta, Maine; Prepared for Central Maine Power Company; Augusta 24, 2007. 

TSA, 1996. Wetlands Construction and Monitoring Report, 100 Percent Remedial Design, O’Connor Company 

Superfund Site, Augusta, Maine. The Smart Associates, Environmental Consultants, Inc. Concord; New 

Hampshire, 1996. 

USEPA, 1989. Record of Decision Summary; U.S. Environmental Protection Agency, Region 1, Boston, 

Massachusetts; September 1989. 

USEPA, 1991. Consent Decree – United States of America, Plaintiff v. Central Maine Power Company, Defendant; 

September 3, 1991. 

USEPA, 7/20/94. Explanation of Significant Differences, O’Connor Company Superfund Site, Augusta, Maine; July 

20. 

USEPA, 10/20/94. Remedial Design/Remedial Action Revised Statement of Work, O’Connor Company Superfund 

Site, Augusta, Maine; October 20. 

USEPA, 9/02. Record of Decision Amendment Operable Unit 2, F. O’Connor Company Superfund Site; U.S. 

Environmental Protection Agency, Region 1, New England; September. 

USEPA, 9/18/03. Amendment to Consent Decree - United States of America v. F. O’Connor Company Superfund 

Site, et. al, in the United States District for the District of Maine; September 18. 

Woodard & Curran, 1996. Management of Migration Groundwater Monitoring Program Sampling and Analysis Plan, 

O’Connor Superfund Site; December 1996 with Amendments. 

Woodard & Curran, 1998. Final Source Control Remedial Action Report, O’Connor Company Superfund Site, 

Augusta, Maine; September 1998. 

Woodard & Curran, 2002. Technical Impracticability Evaluation for OU-2 Management of Migration, O’Connor 

Company Superfund Site, Augusta, Maine; June 2002. 

Woodard & Curran, 4/17/07. O’Connor Company Superfund Site Quality Assurance Project Plan Amendment, 

O’Connor Company Superfund Site, Augusta, Maine; April 17. 
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APPENDIX A: 2009 SITE PHOTOGRAPHS 
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Culvert inlet by Route 17 

Access road looking south 
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Access road looking north 

Eastern slope 
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Culvert inlet under access road 
Central Maine Power (222350.00) October 27, 2009 

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Designated area marker 
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Outlet- Upper Lagoon 

Lower Lagoon 
Central Maine Power (222350.00) October 27, 2009 

Operations and Maintenance Plan

O’Connor beaver dam along Upland Marsh edge - June 25, 2009 

Transformer work area (TWA) wells 
Central Maine Power (222350.00) October 27, 2009 

Operations and Maintenance Plan

Outlet pipe- Lower Lagoon 
Central Maine Power (222350.00) October 27, 2009 

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Outlet pipe- Upper Lagoon 
Central Maine Power (222350.00) October 27, 2009 

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Upland Marsh 

Upper Lagoon 
Central Maine Power (222350.00) October 27, 2009 

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Vehicle barrier gate 
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APPENDIX B: O’CONNOR INSPECTION CHECKLIST 
Central Maine Power (222350.00) October 27, 2009 

Operations and Maintenance Plan 

O’Connor Inspection Checklist 

Inspector: Date:

Weather: Time:

MONITORING/OBSERVATION WELLS 

Well Casing Well Locks Condition Erosion Comments 

MW 104B 

MW 106A 

MW 106B 

MW 501 

MW 502 

MW 503 

MW 507A 

MW 508B 

OW 201B 

OW 202B 

OW 302B 

RW 101 

Follow Up Action Required: 
Central Maine Power (222350.00) October 27, 2009 

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Designated Area 

Boundary Markers Condition Comments 

PTA 

PTB 

PTC 

PTD 

PTE 

PTF 

PTG 

PTH 

PTI 

PTJ 

Follow Up Action Required: 

Surface Soils 

CONDITION LOCATION (MARK ON ATTACHED MAP) 

Excessive Settlement - Ponding 

Erosion Rills 

 

Vegetation – Stressed or Sparse 

Animal Burrows 

Tree and Shrub Encroachment on 

Designated Area 
Central Maine Power (222350.00) October 27, 2009 

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Access Road 

Feature Condition Comments 

Excessive Rutting 

Erosion, Sloughing of Shoulders 

Other 

Follow Up Action Required: 

CULVERTS AND SURFACE DRAINAGE 

Location Condition Comments 

Upland Marsh Culvert – Primary 

Upland Marsh Culvert – Overflow 

Upper Lagoon Culvert Outlet 

Swale Upper to Lower Lagoon 

Lower Lagoon Culvert Outlet 

Drainage Lower Lagoon to Riggs Brook 

Follow Up Actions Required: 

UPLAND MARSH AND LAGOONS 

Location Feature Condition Comments 

Side Slopes Upland Marsh Vegetation 

Side Slopes Upper Lagoon Vegetation 

Side Slopes Lower Lagoon Vegetation 

Follow Up Actions Required: 
Central Maine Power (222350.00) October 27, 2009 

Operations and Maintenance Plan 

INSTITUTIONAL CONTROLS 

Covenant Compliance Comments 

No use of groundwater beneath the Property 

has occurred during the past year without prior 

written approval of MEDEP 

 

No activity which might disrupt remedial or 

monitoring measures has occurred during the 

past year without prior written approval of 

MEDEP 

 

CMP or subsequent owner has maintained the 

Property during the past year in a condition 

adequate to ensure continued compliance with 

all applicable cleanup standards, and to ensure 

the ongoing adequacy of the remediation 

implemented 

 
Central Maine Power (222350.00) October 27, 2009 

Operations and Maintenance Plan 

OTHER OBSERVATIONS/RECOMMENDED ACTIONS 

 CHECK HERE IF ADDITIONAL INFORMATION IS ATTACHED 

Inspector’s Signature Date: 
Central Maine Power (222350.00) October 27, 2009 

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Central Maine Power (222350.00) October 27, 2009 

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APPENDIX C: MONITORING WELL DECOMMISSIONING 

PROCEDURES 
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Operations and Maintenance Plan 

APPENDIX C: 

MONITORING WELL DECOMMISSIONING PROCEDURES 

The State of Maine has not published guidelines or policies specifically concerning the abandonment of 

groundwater monitoring wells at hazardous waste sites. However, the Maine Department of Human 

Services, Bureau of Health has issued Well Drillers and Pump Installers Rules (10-144 Chapter 232), that 

contain guidance detailing the abandonment of drinking water wells (Chapter 5). The objective of the 

Chapter 5 rules is to ensure that abandonment of wells is completed in a manner appropriate to prevent 

potential entry of contaminants into groundwater. Chapter 5 of 10-144 Chapter 232 (Abandonment of Wells) 

is attached, and was utilized in the development of this monitoring well decommissioning plan. 

Monitoring wells proposed to be decommissioned at the O’Connor Company Superfund Site in Augusta, 

Maine will be handled in two ways, depending on whether the well is located inside of or outside of the 

designated area at the Site. The designated area is a three- to four-acre area containing soil contaminated 

with PCBs less than 10 parts per million beneath a 12-inch clean soil cover. It is proposed that monitoring 

wells within the designated area be grouted in place, and terminated at 6-inches below grade (within the top 

12-inches of clean cover soil) to avoid disturbance of potentially PCB-impacted soils in the designated area. 

For wells located outside of the designated area, an attempt will be made to remove the existing well 

construction materials. 

Monitoring well decommissioning procedures are described in detail below: 

Monitoring wells within the designated area 

• Measure well depth and compare to as-built depth; clear any obstructions in the well. 

• Pump via the tremie pipe method (i.e., bottom of well to top), a neat cement/bentonite grout mixture into 

the well or open borehole. 

• Fill the well pipe with the grout material to approximately 6-inches below ground surface. 

• Groundwater that is displaced during the well grouting procedure will be allowed to runoff to the ground 

surface, except at well OW-301B. Based on historic sampling results, displaced groundwater from this 

well will be containerized and sampled for off-site disposal. 

• Remove the well’s protective casing (standpipe). For bedrock wells OW-204B and OW-301B, the well 

casing above ground surface is the protective casing. 
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• Terminate the well approximately 6-inches below grade (using an internal cutting tool, if necessary to 

minimize disturbance of soil), followed by ground surface restoration to surrounding conditions (i.e., 

topsoil consistent with the existing Site cover soils). 

Monitoring wells outside of the designated area

• Measure well depth and compare to as-built depth; clear any obstructions in the well. 

• If possible, remove the existing well construction materials (e.g., screen, riser, steel casing) by directly 

lifting/pulling the material from the ground using the drill rig, while intermittently grouting the hole. Limit 

the length of well material pulled between grouting to prevent collapse prior to grouting, estimated to be 

two feet. Push out the bottom of the well and pump via the tremie pipe method (i.e., bottom of well to 

top), a neat cement/bentonite grout mixture into the well or open borehole. 

• Fill the borehole with the grout material. 

• Groundwater that is displaced during the well grouting procedure will be allowed to runoff to the ground 

surface. 

• Remove the well’s protective casing (standpipe). 

• Terminate the well approximately 3 feet below grade; apply a minimum of one to two feet of concrete 

following by ground surface restoration to surrounding conditions (i.e., topsoil). 

• All extracted well materials will be disposed of or recycled in accordance with applicable regulations. 

A record of decommissioning activities will be completed and maintained, including removal and sealing 

methods, date, depth sealed, and quantity of sealing material used. The monitoring well decommissioning 

activities will be performed by a registered driller in the State of Maine. Woodard & Curran will provide onsite oversight and documentation of the abandonment activities, including a letter report summarizing the 

work performed. All work will be conducted in accordance with the Supplemental Health & Safety Plan 

(April, 2008).