CDW CONSULTANTS, INC....90 Windsor Street, Roxbury, MA June 14, 2013 CDW CONSULTANTS, INC. Page 2 2.2 Land Use and Potential Receptors The Site is currently vacant and there …

40 Speen Street Suite 301, Framingham, MA 01701 508-875-2657 FAX 508-875-6617 www.cdwconsultants.com

CDW CONSULTANTS, INC. CIVIL & ENVIRONMENTAL ENGINEERS

DRAFT

ANALYSIS OF BROWNFIELDS

CLEANUP ALTERNATIVES

90 Windsor Street

Roxbury, MA

DEP Release Tracking Number

3-29641

Prepared For

United Neighbors of Lower Roxbury

P.O. Box 321109

Boston, MA 02123

June 17, 2013

CDW Project # 1365.00

Analysis of Brownfields Cleanup Alternatives 90 Windsor Street, Roxbury, MA

June 14, 2013

CDW CONSULTANTS, INC. Page i

TABLE OF CONTENTS 1.0 INTRODUCTION ...............................................................................................................1 1.1 Purpose .....................................................................................................................1 2.0 BACKGROUND ................................................................................................................1

2.1 Site Location and Description ..................................................................................1 2.2 Land Use and Potential Receptors ...........................................................................2 2.3 Summary of Previous Assessments .........................................................................2 2.4 Site and Hydrogeologic Characteristics ...................................................................3 2.5 Conceptual Site Model .............................................................................................4

3.0 ALTERNATIVES ANALYSIS ..........................................................................................4

3.1 Remedial Action Objectives and Cleanup Goals .....................................................4 3.2 Identification of Remedial Alternatives ...................................................................4 3.3 Evaluation of Remedial Alternatives .......................................................................5 3.4 Comparison of Remedial Alternatives .....................................................................6 3.5 Selection of Remedial Alternative ...........................................................................7

4.0 EPA CLEAN AND GREEN POLICY ...............................................................................7 5.0 PUBLIC PARTICIPATION ...............................................................................................7 FIGURES Figure 1: Site Location Map Figure 2: Site Plan with Sampling Locations Figure 3: Priority Resources Map TABLES Table 1: Remedial Alternatives Evaluation Matrix ATTACHMENT: EPA Region 1 Clean and Green Policy for Contaminated Sites


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CDW CONSULTANTS, INC. Page 1

1.0 INTRODUCTION

CDW Consultants, Inc. (CDW), on behalf of United Neighbors of Lower Roxbury (UNLR), has prepared an Analyses of Brownfields Cleanup Alternatives (ABCA) for the property located at 90 Windsor Street, in Roxbury, Massachusetts (“Site”). This analysis is being prepared as part of UNLR’s Brownfields Cleanup Grant requirements, and is funded by the United States Environmental Protection Agency (EPA).

1.1 Purpose

The purpose of this ABCA is to evaluate and discuss feasible alternatives to remediate the Site to limit potential exposure to future users of the Site. Remediation of the Site will facilitate future redevelopment or restoration of the Site. Alternatives are evaluated and an alternative is chosen that best meets the cleanup goals based on the future use of the property in accordance with the EPA and Massachusetts DEP standards.

2.0 BACKGROUND

2.1 Site and Surrounding Area Description

The Site consists of an approximate 0.1 acre parcel of land located on the corner of Windsor and Warwick Streets in an urban residential area of the Roxbury section of Boston, MA. The Site is identified as Parcel ID #0901960000 with the Boston Assessor’s Department. The building on the Site was constructed in the late 1940s for use as a church and was more recently used as a community center until the mid 1990s. The Site was occupied by two “shanties” in the late 1800’s. From the late 1800s until at least 1946, the Site was a vacant lot. The building is currently used for the storage of landscaping equipment and supplies. The Site parcel is currently owned by UNLR.

The building at the Site consists of a one-story brick building constructed on a masonry block foundation with a full basement. The footprint of the building is approximately 2,100 square feet and is surrounded by asphalt and concrete paved walkways and landscaping. Based on visual evidence, a fire occurred in the building at an unknown time. The Site is partially fenced-in and is accessible to the public.

The Site is abutted to the southwest by a fenced-in community garden owned by the City of Boston and Boston Redevelopment Authority. Melnea Cass Boulevard is located further south of the garden. Residential apartment complexes are located to the north and east along Warwick Street. Undeveloped land abuts the Site to the west and open parkland abuts the Site to the southeast.

Utilities serving the Site include potable water, sanitary sewer, overhead electrical, and natural gas.


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2.2 Land Use and Potential Receptors

The Site is currently vacant and there are no on-site workers. There are no schools or institutions within 500 feet of the Site. The topography of the Site and surrounding area is generally flat. The surrounding area is primarily residential with some mixed commercial. The Site is not located within a current or potential drinking water source area. There are no private drinking water wells located within 500 feet of the Site. There are no surface waters within 500 feet of the Site. The nearest surface water is the Muddy River located approximately 3,000 feet northwest of the Site. In addition, the Site is not located within an area of critical environmental concern or protected open space. According to the current Natural Heritage & Endangered Species Program Atlas of Estimated Habitats of Rare Wetlands Wildlife, the Site is not within an identified area for rare or endangered species of plants or animals.

Because contamination exceeding S-1 cleanup standards may exist within the top 6 inches of the Site and access to the Site is not currently entirely restricted, there exists a potential for human exposure to contaminated soils at the Site. Possible exposure pathways to trespassers on the Site are dermal contact, incidental ingestion, and inhalation of contaminated soil-derived dust. 2.3 Summary of Previous Assessments

A Phase I Environmental Site Assessment (ESA) was completed in 2010 by Nobis Engineering, Inc. as part of a Draft Targeted Brownfields Assessment dated July 2010. Several Recognized Environmental Conditions (REC) were observed within the Site building and include the visual observation of potential asbestos containing materials (ACM), pealing paint that could be lead-based, water leakage into the basement creating potential mold/fungi, and an unknown substance protruding from a pipe connected to the chimney.

In May 2010, Nobis conducted a Targeted Brownfields Investigation to further evaluate RECs identified in the Phase I. A hazardous materials survey including ACM, Lead Based Paint (LBP) and mold testing was performed within the building by the Scott Lawson Group, Ltd. As part of the survey a total of 64 samples were collected for asbestos analysis, three samples were collected for polychlorinated biphenyl (PCB) analysis, three samples were collected for mold and several paint samples analyzed for lead using x-ray fluorescence (XRF) technology.

The results of the hazardous materials building survey indicated that ACM was detected throughout the building. ACM was detected above 1% in floor tiles, mastic, caulking and flashing. LBP was identified in painted surfaces throughout the building. Two areas were identified as having elevated lead (>1 mg/m³) that would require additional testing to determine proper disposal methods. Mold/fungi was identified on several surfaces and materials throughout the building including ceiling tiles, gypsum wallboard, wood ceiling decking, and wood ceiling joists. PCBs were not found in window and door caulking samples.


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Nobis also collected six soil samples throughout the Site with a hand auger. The samples were screened with a photoionization detector (PID) for the presence of volatile organic compounds (VOCs). The samples were collected from unpaved areas at an approximate depth of one to two feet below ground surface (bgs). The samples were analyzed for polycyclic aromatic hydrocarbons (PAHs) and RCRA 8 Metals. Some of the samples were obtained from areas where LBP may have impacted soils. Soil was observed by Nobis to be fill to a depth of two feet and consisted of soil, coal, ash, bricks and clinkers. Groundwater was not encountered, nor analyzed as part of the investigation.

The results of the soil analyses indicated benzo(a)pyrene at concentrations exceeding applicable Massachusetts Contingency Plan (MCP) Reportable Concentrations (RCs) in three samples and lead, chromium and nickel exceeding RCs in one sample.

In accordance with the MCP, the Site was reported to DEP as a 120-day release condition on November 8, 2010. On December 29, 2011, a Tier Classification was submitted by Nobis which classified the Site as Tier II.

2.4 Site and Hydrogeologic Characteristics

The topography of the area is relatively flat with a gradual slope to the northeast. According to the USGS Topographic Map, the Site is located at an elevation of 11 feet mean vertical datum. Rain water would likely either flow overland in paved and concrete walkways to storm drains or infiltrate vertically into the vadose zone to the groundwater in unpaved areas. Storm drains are located at the southern corner of Windsor and Warwick Streets immediately north of the Site and along Melnea Cass Boulevard. According to the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (Panel 25025CO79G), the Site is located within a Zone X, which is classified as an area outside of the 0.2% annual chance floodplain.

Soil encountered during the Nobis investigation consisted of fill material to a depth of two feet. According to the Nobis report, groundwater was not encountered at a depth of two feet and was expected to be encountered deeper than five feet.

According to the U.S. Department of Agriculture’s (USDA) Soil Conservation Service (SCS), the Site soil component is predominantly Urban Land (Udorthents), This map unit consists of filled areas that were previously tidal marshes, river flood plains, bays, harbors, and swamps. The fill material consists of rubble, refuse, and mixed soil material which may include sand, gravel and channel dredgings. Soil permeability in these areas is moderate or slow.


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2.5 Conceptual Site Model

The Site consists of approximately 4,020 square feet of vacant wooded land with the building occupying approximately half of the parcel. Two “shanties” occupied the parcel in the late 1800s. The parcel was vacant for most of the early 1900s until the current building was constructed in the late 1940s. There are no known sources of soil contamination originating at the Site. Soil at all five locations was observed to consist of urban fill with coal klinkers, mixed debris and brick fragments. As with much of Boston and other urban areas, urban fill consisting of coal and coal ash was likely placed on the Site in the late 1800s through the early 1900s. Lead was detected in one soil sample at elevated concentrations and PAHs were detected in three samples at elevated concentrations. The source of the detected PAHs and lead appear to be from urban fill materials. The distribution of contaminants at the Site shows no definitive pattern and appears to be random. Groundwater was not analyzed as part of this investigation, and was not observed in soil at depths up to two feet. Groundwater appears to be located at depths of at least five feet below grade, therefore migration of known soil contamination from the upper fill layer to groundwater is unlikely. In addition, the urban location of the Site would make it difficult to determine likely sources and migration pathways for contaminants that might be present in groundwater. 3.0 ALTERNATIVES ANALYSIS

3.1 Remedial Action Objectives and Cleanup Goals

The objective of the remedial program at the Site is to achieve a permanent solution and MCP Site closure, and to demonstrate that a condition of No Significant Risk exists for current and future use of the property. This would be documented in a Response Action Outcome submittal to DEP. Elimination of potential dermal, vegetable uptake and inhalation pathways would be required. If impacted soil will remain on the Site after remediation, an Activity and Use Limitation (AUL) may be required. Abatement of all hazardous building materials will occur in conjunction with the selected soil remediation alternative.

3.2 Identification of Remedial Alternatives

Several possible remedial alternatives were evaluated for addressing contaminated soil at the Site. Based on an initial screening of these, a limited number of feasible alternatives were evaluated that could be implemented that would meet the needs for the anticipated reuse of the property. The no action scenario was evaluated to establish a basis for remedial actions at the Site. The remedial alternatives identified for consideration under this alternatives analysis include the following:


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Soil Excavation and Off-site Recycling or Disposal Limited Soil Excavation and Off-site Recycling or Disposal In-situ Chemical Oxidation No Action

3.3 Evaluation of Remedial Alternatives

Each of the above alternatives were evaluated to determine if they would achieve a permanent solution under the MCP. Technological and economic feasibility were also incorporated into the evaluation. A table comparing the estimated costs for each alternative is included as Table 1.

Option #1 - Soil Excavation and Off-site Recycling or Disposal

This alternative involves the excavation and off-site recycling or disposal of the top two feet of urban fill soils throughout the entire parcel outside the footprint of the building. The intent is to reduce the risk to surface soils while allowing unrestricted recreational use of the Site. This includes an approximate 2,088 square foot area. Based on an excavation depth of two feet in this area, the volume of soil is estimated at 150 cubic yards. Although the excavation would be completed up to the existing building, due to the shallow depth, no shoring is anticipated. Excavation dewatering is also not anticipated under this scenario as groundwater is anticipated to be located at a depth greater than two feet. Due to area constraints at the Site, soil would need to be pre-characterized to determine disposal options and loaded directly onto trucks during excavation. Confirmatory soil sampling and analyses would be conducted after excavation. Based on preliminary laboratory data, it is anticipated that the soil would be suitable for asphalt batch recycling or thermal treatment as remediation waste under the MCP.

Under this scenario, it is likely that some contaminated soils would remain below two feet requiring a warning marker layer and AUL to maintain a condition of No Significant Risk under the MCP.

Option #2 - Limited Soil Excavation and Off-site Recycling or Disposal

Based on initial soil results, targeted soil removal may be appropriate to mitigate the highest concentrations of lead and PAHs in soil. The intent is to conduct risk reduction to reduce overall soil exposure. This option would require additional soil sampling to fill in data gaps and determine appropriate areas to target for removal. If area permits, soil may be stockpiled on Site prior to off-site recycling or disposal. Shoring or dewatering is not anticipated under this scenario. Up to 75 cubic yards of soil may be removed as part of this scenario. Site closure under the MCP is dependent upon confirmatory soil sample results. Based on preliminary laboratory data, it is anticipated that the soil would be suitable for asphalt batch recycling or thermal treatment as remediation waste under the MCP.


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Option #3 - In-situ Chemical Oxidation

In-situ chemical oxidation involves the injection into the remediation area of an oxidant such as hydrogen peroxide or potassium permanganate, a catalyst such as ferrous sulfate, and other process-enhancing additives such as acids (to lower the soil pH). The oxidation process transforms contaminants into water and carbon dioxide. This is a relatively innovative treatment technology, which is reasonably likely to result in a permanent solution. It is most effective for groundwater treatment, but under certain circumstances, can also be used to treat soils. This technology may be effective on PAHs, however, would not be effective on reducing concentrations of total metals. This alternative will not reduce risks from heavy metals resulting in significant limitations on re-use and redevelopment of the Site. Therefore, this alternative is option will not be included in the comparison analysis and will not be considered further. . Option #4 - No Action

This alternative involves no remedial actions, maintaining current Site conditions and implementing an AUL to restrict future use. This alternative would not reduce risk at the Site and would involve significant limitations on the reuse and redevelopment of the Site. Because of this, this option will not be included in the comparison analysis and will not be considered further.

3.4 Comparison of Remedial Alternatives

Options #1 and #2 would be moderately easy to implement due to the relatively small area(s) to excavate, shallow depth of contaminants, and lack of the need for excavation dewatering.

Given the relatively small size of the parcel, the cost to implement Options #1 and #2 are comparable. For Options #1 and #2, much of the cost is equipment mobilization. While less soil would be disposed of under Option #2, it would require more sampling and analyses, and possibly a second mobilization to remove additional soils. Option #1 could be completed within one week of Site work. Option #2 would require a more expanded timeframe while sample results are evaluated.

Option #1 is considered the most reliable option for ensuring public health is protected from exposure during future use of the Site, and achieving Site closure. Because the top two feet of soils throughout the Site would be removed, there would be no data gaps where residual concentrations of contaminants might remain in that zone. This option would have a very low potential for failure. Both options would require an AUL to restrict future use of the Site, but uses under option #1 will not preclude unrestricted access for passive recreation.


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3.5 Selection of Remedial Alternative

Option #1 was chosen as the preferred remedial alternative. Due to the limited size of the area, excavation of the top two feet throughout the parcel is the most technologically feasible, cost effective and reliable option that would achieve a permanent solution under the MCP. This option also has the shortest implementation time. Under this option, an AUL would be implemented to restrict access to soils below two feet and limit future use of the Site.

4.0 EPA CLEAN AND GREEN POLICY

To the extent possible, the project work will incorporate relevant and feasible opportunities for achieving green remediation goals. These include:

Reducing energy consumption Minimizing waste generation Reducing water use Eliminating sedimentation and erosion Substituting recycled materials for virgin materials Supporting Environmental Sustainable Site Re-Use

A copy of the EPA Region 1 Clean and Green Policy for Contaminated Sites is included as an attachment.

5.0 PUBLIC PARTICIPATION

EPA, in consultation with UNLR, will approve a remedy only after the public is provided with an adequate time period for review and comment, all comments have been reviewed, and responses have been prepared to address the comments. Public comments on the proposed remedy are important to the remedy selection process. EPA may ask that the UNLR modify the proposed remedy or select another remedy, based on new information or comments received from the public.

The UNLR will solicit input from the public by publishing a public notice soliciting input on the draft ABCA.

CDW CONSULTANTS, INC.

FIGURES

CDW CONSULTANTS, INC.SITE LOCATION MAP

90 WINDSOR STREET, ROXBURY, MA

PROJECT NO.: 1365.00APROX. SCALE: 1:25,000

SOURCE: MA Geographic Information System

FIGURE 1

I

SITE

UNITED NEIGHBORS OF LOWER ROXBURYEPA - BROWNFIELDS GRANT

RTTN: 3-29641

bmiller

Typewritten Text

FIGURE 3


TABLES

Table 1Remedial Alternative Evaluation Matrix

Remedial AlternativeImplementation

RisksEffectiveness &

ReliabilityDifficulty of

Implementation Timeliness Estimated CostOption #1 Soil Excavation and Off-site Recycling/Disposal (top 2 feet) low high moderately easy short $60,000 Option #2 Limited Soil Excavation and Off-site Recycling/Disposal (targeted areas) moderate moderate moderately easy moderate $50,000 - $70,000*

Building Hazardous Materials Abatement NA NA NA NA $23,000*Costs are dependent upon sample results at completion of first targeted soil excavation and disposalBoth options assume AUL placed on the Site



ATTACHMENT

EPA Region 1 Clean and Green Policy for Contaminated Sites

Documents

CDW CONSULTANTS, INC....90 Windsor Street, Roxbury, MA June 14, 2013 CDW CONSULTANTS, INC. Page 2 2.2 Land Use and Potential Receptors The Site is currently vacant and there …