Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
TABLE OF CONTENTS
1
INTRODUCTION ............................................................................................... 1
2
REMEDIAL ACTION ALTERNATIVES ................................................. 2
2.1
REMEDIAL ACTION ALTERNATIVES IDENTIFICATION ........................................... 2
2.1.1
Soil Excavation, Disposal and Placement of New Surface ......................... 2
2.1.2
Placement of Surface Cover........................................................................ 2
2.1.3
Placement of Additional Surface Cover With a Reinforced Geotextile ...... 2
2.2
REMEDIAL ACTION EVALUATION ........................................................................ 3
2.2.1
Remedial Actions Effectiveness................................................................... 3
2.2.2
Remedial Actions Long/Short-Term Reliability .......................................... 3
2.2.3
Remedial Actions Difficulty of Implementation .......................................... 3
2.2.4
Remedial Actions Cost Comparison ........................................................... 4
2.2.5
Remedial Actions Technological Feasibility .............................................. 4
2.3
REMEDIAL ACTION SELECTION ............................................................................ 5
3 METHOD 3 RISK ASSESSMENT OF SELECTED REMEDIAL
ACTION .......................................................................................................................... 6
3.1 SITE-SPECIFIC CHARACTERISTICS ......................................................................... 6
3.1.1
Physical Characteristics ............................................................................. 6
3.1.2
Extent of Release ......................................................................................... 6
3.1.3
Contamination Characterization ................................................................ 6
3.2
RECEPTOR INFORMATION..................................................................................... 7
3.2.1
Human Receptor Identification ................................................................... 7
3.2.2
Environmental Receptor Identification ....................................................... 7
3.2.3
Site Activities and Uses Identification ........................................................ 7
3.3
SOIL CLASSIFICATION .......................................................................................... 7
3.3.1 Soil Exposure Points and Exposure Concentrations ........................................ 8
3.4
GROUNDWATER CLASSIFICATION ........................................................................ 8
3.4.1
Groundwater Exposure Points and Exposure Concentrations ................... 8
3.5
HOT-SPOT ASSESSMENT .................................................................................... 10
3.6
IMMINENT HAZARD EVALUATION ...................................................................... 10
3.7
DATA USABILITY ............................................................................................... 12
3.8 METHOD 3 RISK ASSESSMENT CONCLUSION ....................................................... 12
3.8.1
Risk to Safety ............................................................................................. 13
3.9
SUMMARY AND CONCLUSION OF METHOD 3 RISK ASSESSMENT ....................... 13
4
PHASE III SUMMARY AND FINDINGS ............................................... 14
5
COMPLETION STATEMENT AND LSP OPINION ......................... 15
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
FIGURES:
Figure 1
Figure 2
Figure 3
USGS Locus Map
Site Plan
MAGIS MAP
APPENDICES:
Appendix A
Appendix B
Appendix C
Appendix D
Public Involvement Notices
Soil Analytical Summary Tables
BWSC Form 108 as E-filed
Copy of Letter of Agency
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
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Phase III MCP Report
Margin Street Park, Beverly, MA
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AEG Project # 1667
February 2007
INTRODUCTION
On behalf of the City of Beverly, Massachusetts, Alliance Environmental Group, Inc.
(AEG) has completed the following Phase III – Identification, Evaluation, and Selection
of Comprehensive Remedial Action (“Phase III”) for a Disposal Site (hereinafter referred
to as “Site”) assigned Release Tracking Number (RTN) 3-19224 by the Massachusetts
Department of Environmental Protection (MADEP). A United States Geological Survey
(USGS) Map showing the location of the Site is presented as Figure 1. In addition, a plan
depicting general Site conditions and locations of sampling points described herein is
attached as Figure 2. Finally, a Massachusetts Geographical Information System
(MAGIS) Map has been attached as Figure 3.
This Phase III has been completed in accordance with 310 CMR 40.0850 of the
Massachusetts Contingency Plan (MCP, 310 CMR 40.0000). The purpose of this Phase
III study is to identify, evaluate and select a remedial action alternative that is a
Permanent or Temporary Solution and is reasonably likely to achieve a level of No
Significant Risk. In addition, the feasibility of achieving background is also evaluated.
The following sections outline in detail the results of the Phase III study.
As required by 40.0863, AEG has notified the Chief Municipal Officer and Board of
Health for the City of Beverly, MA. Copies of the notices have been provided in
Appendix A.
The person responsible for requesting this Phase III is:
Mr. Frank J. Killilea, Jr., PE
Director of Engineering
City of Beverly
191 Cabot Street
Beverly, MA 01915
978-921-6000 x 403
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Phase III MCP Report
Margin Street Park, Beverly, MA
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AEG Project # 1667
February 2007
REMEDIAL ACTION ALTERNATIVES
The results of the Method 1 Risk Assessment, as summarized in the Interim Phase II Comprehensive Site Assessment (“Phase II”), completed by AEG and dated February
2007, show that a condition of Significant Risk exists for soil on the Site and, as such,
further response actions are needed to mitigate risk. Accordingly, AEG has prepared the
following Phase III study to satisfy the requirements of 310 CMR 40.0850.
2.1
REMEDIAL ACTION ALTERNATIVES IDENTIFICATION
The following sections evaluate three remedial action methods that could be employed at
the Site and describes the selection method that was used to choose the recommended
alternative. This is in compliance with 310 CMR 40.0855 through 40.0859.
2.1.1 Soil Excavation, Disposal and Placement of New Surface
Based upon the results of the Phase II investigation, contamination at the Site is
associated with urban fill materials. The materials were deposited at the Site a number of
years ago along a portion of the Bass River formerly known as Bass Creek. Subsurface
investigation shows the materials are mainly comprised of ash resulting from the
combustion of wood and coal, although other miscellaneous debris such as glass and
brick were found. Contaminants associated with the fill include various PAHs and metals
(mainly lead and chromium). A Method 1 Risk Assessment of conditions at the Site
show a level of Significant Risk does exist with respect to soil due to the presence of
contaminants within the top 3’ below surface grade (bsg) at levels exceeding applicable
MCP S-1 GW-2/3 Soil Standards.
Therefore, one option to achieve a level of No Significant Risk at the Site is to excavate
the top three feet, dispose of the soil, and place three feet of clean cover. In areas that
have asphalt cover, an additional 4” layer of asphalt would be installed. To maintain this
condition of No Significant Risk, an Activity Use Limitation would be filed for the Site.
2.1.2 Placement of Surface Cover
Another option that would achieve a level of No Significant Risk involves the placement
of 3 feet of clean soil over the existing grade of the entire park in order to provide a
barrier to direct contact. In areas that have asphalt cover, an additional 4” layer would be
installed. Again, this option would require the filing of an AUL.
2.1.3 Placement of Additional Surface Cover With a Reinforced Geotextile
In this scenario, a reinforced geotextile would be placed over the entire Site to act as a
barrier to penetration into the contaminated soils below and act as an indicator barrier.
Once the textile has been placed, two feet of clean soil with a vegetative surface would be
installed. In areas that have an existing asphalt cover, an additional 4” layer would be
installed. In this scenario, cutting along the edges would need to be completed in order
for the required depth of cover to be achieved along edges (i.e. sidewalks and asphalt
areas and building) to be met. The materials, cut prior to the placement of the geotetxtile,
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
would be redistributed over the existing grade and capped over. This option would also
include filing an AUL.
2.2 REMEDIAL ACTION EVALUATION
When selecting the most appropriate remedial action for the Site that could render a level
of No Significant Risk, AEG considered various criteria listed in 310 CMR 40.0858 and
40.0860 of the MCP, including the effectiveness of the approach, long/short-term
reliability, practicality of completion, cost of completion, technological feasibility, and an
analysis of whether background could be reached.
2.2.1 Remedial Actions Effectiveness
In affect, all of the identified remedial actions will achieve a permanent solution and
provide a level of No Significant Risk. However, none of the options will reduce levels
of contaminants at the Site to concentrations that achieve or approach background. It has
been demonstrated within the Phase II that contamination is associated with fill material
found to be situated within the top 3’ bsg and extending as deep as 18’ bsg down to
where native marine silt was observed. In order to reach background, it is estimated that
from surface grade to at least 18’ bsg of fill/soil would need to excavated and disposed.
The park is around 3.6 acres and the resulting amount of soil excavated would be
approximately 240,000 tons. Using a benchmark figure of $200 per ton for excavation,
loading, transportation and disposal, the cost of disposing this amount of material would
be roughly $5,200,000 and does not included costs associated with management and
consulting. Based upon this evaluation, it is infeasible to reach background at the Site.
2.2.2 Remedial Actions Long-/Short-Term Reliability
It is the opinion of AEG that any one of the remedial alternatives considered for the Site
would have long-term reliability. In each scenario, general maintenance would be
necessary and would be institutionally controlled by implementation of an AUL.
2.2.3 Remedial Actions Difficulty of Implementation
When evaluating the difficulty of implementing each of the alternatives, AEG considered
the disruption to the surrounding area, time to complete the project, and problems
associated with meeting grades around the existing buildings, public walkways and
seawall along the Bass River.
Excavation of the top 3’ of soil at the Site would result in the movement and disposal of
approximately 17,000 cubic yards of material. Based upon previous experiences and the
use of a reasonable amount of equipment, AEG estimates that, on average, 10 trucks
carrying approximately 20 yards of material could be shipped each day. Using this as a
baseline, it would take a little under 3 months to complete the removal process, during
which extensive security and public safety issues would need to be addressed because
contaminated materials would be extensively disturbed and exposed.
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
Placement of additional cover in the form of 3 feet of soil would also be a complicated
task. Similar to the removal of the top 3’, placement would take roughly the same time,
and issues regarding edge conditions and maintaining appropriate grades for recreation
uses including a baseball field would be difficult.
Finally, placement of an additional soil cover over a geotextile membrane, in the opinion
of AEG, would be a more feasible approach since grades would be more easily managed,
material could be placed and supplied in a more timely fashion, and the cost of
completing the project is much more reasonable, as described below. In addition, this
approach would still reach and maintain a level of No Significant Risk.
2.2.4 Remedial Actions Cost Comparison
When comparing the costs of completing each alternative, AEG considered materials and
time as the major factors.
Excavation of the top 3’, loading, transportation, disposal, and placement of a new
surface would be labor intensive and costly. As indicated above, disposal alone of the
material would cost around $5,200,000. Contracting and consulting expenses are
estimated to cost somewhere in the vicinity of $250,000, and placement of new surfaces,
assuming a benchmark figure for soil of $15 per yard in place, is approximately
$315,000. In summary this option would cost somewhere in the vicinity of $5,765,000.
Placement of 3’ of cover would result in contacting and consulting costs somewhere
around $150,000. In addition the cost for materials would be approximately $315,000
totaling $465,000 to complete the project.
The final option would be able to be completed in a more timely fashion, because less
material would be needed to be handled and Site management issues, including dealing
with edge conditions and restoration of the facility grades for future recreational use,
would be easier and less expensive. To complete this option, around 11,500 cubic yards
of soil would be needed at a cost of approximately $172,500 in place. The reinforced
geotextile fabric is estimated to cost around $7,000 and, due to the inherent shortened
time to compete the project, it is estimated contracting and consulting fees would total
around $100,000. This option would total somewhere around $273,000 and provide a
condition of No Significant Risk.
2.2.5 Remedial Actions Technological Feasibility
All remedial action options considered here for the Site are considered technologically
feasible because they all include proven methods that can render a level of No Significant
Risk. However, in order to extrapolate further, AEG considered the use of soil
stabilization in conjunction with all of the proposed remedial actions. Based upon AEG’s
past experience on various projects that involved the use of soil stabilization methods,
this would cost of approximately $40 per ton. Because the risk associated with
contamination at the Site is due to direct contact, and the stabilization method does not
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
remove this risk, use of this technology in conjunction with the proposed remedies is not
worthwhile, especially since it involves greater costs.
2.3 REMEDIAL ACTION SELECTION
Based upon the above identification and evaluation of remedial alternatives, it is apparent
that the best approach is the placement of a geotextile with an additional 2’ of surface
cover to act as a barrier to direct contact. Along with this barrier, the Site will be
institutionally controlled and access to deeper soils prohibited via an AUL.
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Phase III MCP Report
Margin Street Park, Beverly, MA
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AEG Project # 1667
February 2007
METHOD 3 RISK ASSESSMENT OF SELECTED REMEDIAL ACTION
To further validate that implementation of the selected remedial action will lead to a
conditions of No Significant Risk at the Site, AEG has completed a Method 3 Risk
Assessment (“Method 3”) in accordance Section 40.0990 of the MCP.
3.1
SITE-SPECIFIC CHARACTERISTICS
3.1.1 Physical Characteristics
The Site is located along the Bass River and is developed with a pumping station used for
the control of stormwater and a recreational park known as Innocenti Park. Topography
of the Site is mostly flat with a gentle slope to the west toward the Bass River. Surface
conditions are grass; asphalt-paved walkways, parking area, basketball court, hockey
court, and skateboard court; and two small structures built slab-on-grade, the pump
station and a small youth center.
During subsurface investigation of the Site, the geology was identified to be comprised of
urban fill materials including coal ash, wood ash, and other miscellaneous fill such as
wood, brick, and glass, over a native marine silt. Groundwater was reached across the
Site and found to be situated at approximately 6’ bsg and to be tidally influenced.
3.1.2 Extent of Release
Using the subsurface and historical data described earlier in the Phase II Report, the
release is associated with urban fill material that was deposited some time ago. The
extent of the fill material appears to include the entire park and extend underneath
McPherson Drive and southerly underneath properties along the Bass River. Vertically,
the fill has been found to be near surface grade and extend to approximately 18’ bsg to
native marine silts.
3.1.3 Contamination Characterization
Contamination at the Site is associated with urban fill material that has been laboratory
tested for various analytes. The contaminants found include PAHs and metals (mainly
lead and chromium) in soil. Groundwater analysis from various areas of the Site did not
detect targeted analytes in exceedence of any MCP Method 1 GW-2/3 Groundwater
Standards, which indicates contaminants are confined to soil.
In summary, the contaminants found at the Site are persistent in the environment and risk
associated with them is due to direct contact. This conclusion in based upon the nature of
the contaminants being non-volatile and confined to soil.
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Phase III MCP Report
Margin Street Park, Beverly, MA
3.2
AEG Project # 1667
February 2007
Receptor Information
3.2.1 Human Receptor Identification
Contamination at the Site during subsurface investigation was found on average to be
found within 3' of the surface and extend to as deep as approximately 18’ bsg. As a result
of the placement of a reinforced geotextile and 2’ of clean soil on the Site, the only
human receptor group identified who would have direct contact with contaminated soils
are future Construction and Utility workers. An AUL would prevent other potential
receptors from gaining access to contaminated soils by securing the Site during any
construction or utility work that would involve disruption of the contaminated soils.
3.2.2 Environmental Receptor Identification
In determining the environmental receptors that could come in contact with
contamination at the Site, receptors likely to be present at the Site or in the surrounding
area were considered.
The Site is located along the Bass River and, according to the MAGIS, is designated as
open space, and a portion of the Site is located within the Federal Emergency
Management Agency (FEMA) 100-year floodplain.
Biota at the Site or within the surrounding area includes wildlife such as squirrels, fish
and shellfish, as well as plants such as trees and grasses.
The only habitat at the Site or within the surrounding area is the Bass River. According
to the MAGIS, Areas of Critical Environmental Concern (ACEC) are not located at the
Site or within the surrounding area.
3.2.3 Site Activities and Uses Identification
Current and foreseeable activities associated with environmental receptors include
forging by wildlife and potentially seasonal nesting by birds.
3.3
Soil Classification
Based on Site conditions and exposure scenarios, AEG has characterized soil at the Site
as being S-1 as defined by 310 CMR 40.0933. This decision is based on the following:
a. The potential exists for construction or utility workers to be present on-Site and,
as such, it is assumed that, when present, they would have a high intensity of use.
b. The majority of the Site will be covered with a geotextile membrane and 2’ of
clean soil. It will be assumed that any future construction or utility workers will
have access to contaminated soil and as such the soil will be considered
“accessible.”
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
3.3.1 Soil Exposure Points and Exposure Concentrations
The Exposure Point Concentration for soils, both surface and subsurface, is defined as the
average of all soil analytical results on the Site. Tables listing the contaminant
concentrations detected at each soil boring advanced have been provided in Appendix B
– Soil Analytical Summary Tables. A table displaying the average of all soil analytical
has been provided below. Note that the table below does not include data from the CDM
cleanup around the pump station because these soils were reportedly removed. As
observed below, chromium, lead, and benzo(a)pyrene, on average, exist above the
applicable MCP Method 1 S-1 GW-2/3 Soil Standards, which categorically represents a
condition of Significant Risk.
3.4
Groundwater Classification
Based on Site conditions and exposure scenarios, AEG has characterized groundwater at
the Site in accordance of 310 CMR 40.0932. According to MAGIS, groundwater at the
Site and within the surrounding area is not within a current or potential drinking water
source area and is therefore not considered GW-1.
Because there is an occupied building on-Site, groundwater is considered GW-2 and, due
to all groundwater being considered a potential source of discharge to surface water, GW3 is also appropriate. Therefore, groundwater at the Site is considered GW-2/3.
3.4.1 Groundwater Exposure Points and Exposure Concentrations
As summarized in Section 3.2.1, above, groundwater at the Site was laboratory tested for
the 8 RCRA Metals, VOCs, MA-EPH with PAH targets, and sulfides, none of which
were detected at or above an applicable MCP Method 1 GW-2/3 Groundwater Standard.
As a result, current conditions at the Site, with respect to groundwater, categorically
represent a condition of No Significant Risk of Harm to health, safety, public welfare and
the environment.
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
Average Site-Wide Exposure Point Concentrations (all depths)
Site-Wide Average
Contaminant
Concentration (mg/Kg)
MCP Method 1
S1 GW-2/3 Soil
Standard
METALS
Arsenic
12.1
20
Barium
213.7
1000
Cadmium
1.2
2
Chromium
41.6
30
Lead
1,361.6
300
Mercury
0.7
20
Selenium
4.7
400
Silver
0.6
100
MA-EPH
C9-C18 Aliphatics
115.5
1000
C19-C36 Aliphatics
275.8
2500
C11-C22 Aromatics
322.6
800
SVOCs
2-Methylnaphthalene
0.3
500
Acenaphthene
0.5
1000
Aceaphthylene
0.6
100
Anthracene
1.3
1000
Benzo(a)anthracene
3.0
7
Benzo(a)pyrene
3.0
2
Benzo(b)fluoranthene
2.8
7
Benzo(g,h,i)perylene
1.5
1000
Benzo(k)fluoranthene
2.3
70
Chrysene
3.7
7
Dibenzo(a,h)anthracene
0.4
0.7
Fluoranthene
7.3
1000
Fluorene
0.6
1000
Indeno(1,2,3-cd)pyrene
1.5
7
Naphthalene
0.3
40/500
Phenanthrene
7.6
1000/100
Pyrene
5.5
1000
VOCs
1,2,4-Trimethylbenzene
0.5
NS
1,3,5-Trimethylbenzene
0.2
NS
4-Isopropyltoluene
0.09
NS
Isopropylbenzene
0.1
NS
n-Propylbenzene
0.1
NS
sec-Butylbenzene
0.2
NS
tert-Butylbenzene
0.1
NS
Toluene
0.1
300/500
Xylens (total)
0.1
300
0.5
PCBs (Total)
2
Notes
1. Shaded: Average concentration in exceedence of MCP Method 1 S-1 GW-2 and/or
GW-3 Soil Standard
2. MCP Method 1 S-1 GW-2/3 Soil Standards as defined in 310 CMR 40.0975(6)(a), Table
2.
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Phase III MCP Report
Margin Street Park, Beverly, MA
3.5
AEG Project # 1667
February 2007
Hot-Spot Assessment
As part of the Method 1 Risk Assessment, AEG completed a Hot Spot assessment in
accordance with 40.0924. A Hot Spot is defined by the MCP as a discrete area where the
average contaminant concentration is greater than 10 but less than 100 times the average
concentration in the immediate surrounding area, unless there is no evidence that the
discrete area would be associated with greater exposure potential than the surrounding
area.
Only lead, of the analytes exceeding a relevant MCP Standard, has the potential of being
a defined Hot Spot. Analytical results indicate that the highest level of lead in soil was
detected in soil from boring AE-118 (1’-3’ bsg) at 39,200 ppm. The average lead
concentration in the area surrounding AE-118 is approximately 667 ppm. Based upon
AE-118 not being located on a playing field or within an area that would represent a
greater potential of use than the surrounding area, a factor of 100 times was used in
determining whether a Hot Spot exists.
The concentration of lead at AE-118 is less that 100 times the average within the
immediate surrounding area and, as such, a Hot Spot categorically does not exist.
3.6
Imminent Hazard Evaluation
In accordance with 40.0950 of the MCP and use of the Site, AEG completed the
following Imminent Hazard Evaluation. As documented in the previous sections, soil,
unlike groundwater, has been found to pose a Significant Risk. Consequently, AEG has
investigated whether conditions with respect to soil pose an Imminent Hazard.
As stipulated in Section 40.0953(2) of the MCP, Exposure Point Concentrations
associated with the Immediate Hazard Evaluation are defined as those concentrations at
ground surface or within the top 12” bsg. A total of 8 samples were collected within the
top 12” bsg and laboratory analyzed for the RCRA 8 Total Metals, MA-EPH and PAHs.
Using the, “Guidance for Disposal Site Risk Characterization” MADEP Interim Final
Policy WSC/ORS-95-141, dated July 1995, AEG assessed the potential of Site conditions
to pose an Imminent Hazard. As a general indicator of an Imminent Hazard, AEG
compared Site-wide averages of contaminants, shown in the table below, to multiples of
standards defined in Table 5 of 310 CMR 40.0985. Standards in Table 5 were used
because they consider risk solely associated with direct contact (dermal or ingestion).
Using a multiple of 10 as a “rule-of-thumb,” values in Table 5 of 310 CMR 40.0985 were
recalculated to represent concentrations that could pose an Imminent Hazard, and these
concentrations compared to the average contaminant concentrations detected within the
top 12” bsg. This comparison did not indicate an exceedence of the adjusted standards,
indicating an Imminent Hazard does not exist at the Site.
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
Average Site Wide Exposure Point Concentration (Top 12”)
Site-Wide
Average
Contaminant
Concentration
*Adjusted Method 2
S-1 Soil Standard
Metals
Arsenic
12.1
200
Barium
112.8
10,000
Cadmium
1.6
20
Chromium
17.8
300
Lead
564.0
3,000
Mercury
0.3
200
Selenium
3.9
4,000
Silver
0.3
1,000
MA-EPH
C9-C18 Alophatics
74.5
10,000
C19-C36 Aliphatics
74.5
25,000
C11-C22 Aromatics
74.5
8,000
SVOCs
2-Methylnaphthalene
0.4
5,000
Acenaphthene
0.5
10,000
Acenaphthylene
0.7
1,000
Anthracene
1.4
10,000
Benzo(a)anthracene
3.4
70
Benzo(a)pyrene
3.5
20
Benzo(b)fluoranthene
3.1
70
Benzo(g,h,i)perylene
2.1
10,000
Benzo(k)fluoranthene
2.8
700
Chrysene
4.5
70
Dibenzo(a,h)anthracene
0.7
7
Fluoranthene
8.7
10,000
Fluorene
0.7
10,000
Indeno(1,2,3-cd)pyrene
2.2
7
Naphthalene
0.5
5,000
Phenanthrene
5.6
10,000
Pyrene
6.9
10,000
VOCs
1,2,4-Trimethylbenzene
0.04
NS
1,3,5-Trimethylbenzene
0.04
NS
4-Isopropyltoluene
0.04
NS
Isopropylbenzene
0.04
NS
n-Propylbenzene
0.04
NS
sec-Butylbenzene
0.04
NS
tert-Butylbenzene
0.04
NS
Toluene
0.04
5,000
Xylenes (total)
0.1
5,000
0.2
PCBs (Total)
20
Notes
1. Units: mg/Kg (ppm).
2. MCP Method 2 S-1 Soil Standards adjusted based upon MADEP Interim Final
Policy WSC/ORS-95-141, dated July 1995, and based upon standards in 310 CMR
40.0985, Table 5.
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Margin Street Park, Beverly, MA
3.7
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February 2007
Data Usability
This section summarizes a quality control/quality assurance (QA/QC) assessment of the
analytical data used in this submittal. Pursuant to Section 40.0017(1) of the MCP, “any
person undertaking response actions under the provisions of the MCP shall ensure that
analytical data and environmental monitoring data used in support of recommendations,
conclusions, or Licensed Site Professional (LSP) Opinions with respect to assessment,
removal, or containment actions is scientifically valid and defensible, and of a level of
precision and accuracy commensurate with its stated and intended use.”
For this Method 3 Risk Assessment, AEG reviewed analytical QA/QC reports from the
soil samples collected and analyzed in December 2006. This data usability evaluation
includes the following: (i) assurance that the detection of surrogate analytes added to
submitted samples were within acceptable ranges, (ii) assurance that sample blanks
contained no analytes at values greater than 3% of any reported values, (iii) assurance
that analyses were performed within acceptable time limitations, (iv) assurance that only
published USEPA approved analytical methods were used, (v) assurance that detection
limits for all analytes were stated and were low enough to evaluate a possible exceedance
of a referenced standard, and (vi) sample collection was performed by persons who are
qualified by education, training and experience.
AEG concludes that, after reviewing the soil analytical QA/QC, the qualifications to the
data for analytes are of no import and do not impact the collective body of data used
when drawing conclusions. Thus, AEG is confident that this data can be relied upon as
representative of Site conditions.
3.8
Method 3 Risk Assessment Conclusion
Based upon the results of a Method 3 Risk Assessment (Construction Worker Scenario),
performed using the MADEP ShortForm Version 01-07, the Hazard Index (HI) was
determined to be 2.0 and the Excess Lifetime Cancer Risk (ELCR) 5 X 10-7. The
spreadsheets are presented in Appendix C. Compared to the maximum allowable HI of
1.0 and the maximum allowable ELCR of 1 X 10-5, it has been demonstrated that a level
of Significant Risk exists with respect to soil conditions at the Site. However, if an AUL
is implemented that specifies a requirement that all on-Site workers must wear a
suitable respirator then a condition of no Significant Risk can be achieved. These
respirators must cover both nose and mouth to prevent the respiration/ingestion of
contaminated soil particulates. In addition, this AUL must specify that all non-workers
must be kept off the Site during construction, which could expose the public to
contaminated soil, is underway. As part of this risk assessment, an evaluation of Hot
Spots and Imminent Hazards was completed, which did not indicate the presence of
either.
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Phase III MCP Report
Margin Street Park, Beverly, MA
AEG Project # 1667
February 2007
3.8.1 Risk to Safety
As required under 310 CMR 40.0971(5), a qualitative characterization of risk to safety
was conducted for the Site. The purpose of evaluating the risk of harm to safety is to
identify conditions that have resulted in or may result in a release of oil and/or hazardous
material currently or in the foreseeable future that will pose a threat of physical harm or
bodily injury to people. The risk to safety is primarily based on a characterization of
contaminants associated with flammability and ignitability, corrosivity, reactivity and
infectious nature. Contaminants present at the Site do not exhibit these characteristics
and consequently there exists a condition of No Significant Risk to safety now and for the
foreseeable future.
3.9
Summary and Conclusion of Method 3 Risk Assessment
AEG has completed this Method 3 Risk Assessment to validate that the selected remedial
action will render a level of No Significant Risk at the Site, once implemented. A
Method 3 Risk Assessment (Construction Worker Scenario), determined that the HI= 2.0
and the ELCR= 5 X 10-7. As part of the chosen remedial action, therefore, an AUL will
specify that all future on Site Construction/Utility workers performing work resulting in
direct contact with contaminated soils must wear a suitable respirator which will cover
both nose and mouth to prevent the respiration/ingestion of contaminated soil
particulates. In addition, this AUL must specify that all non-workers must be kept off the
Site while construction, which exposes the public to contaminated soil, is underway. As
part of the risk assessment, an evaluation of Hot Spots and Imminent Hazards was
completed, which did not indicate the presence of either.
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Phase III MCP Report
Margin Street Park, Beverly, MA
4
AEG Project # 1667
February 2007
PHASE III SUMMARY AND FINDINGS
AEG has completed this Phase III report in accordance with 40.0850 of the MCP. The
Phase III included identification and evaluation of various response actions that could
yield a condition of No Significant Risk at the Site pertaining to direct contact with
contaminated soils. After careful evaluation, which included effectiveness, reliability,
difficulty of implementation, cost, and technological feasibility, AEG selected placement
of a reinforced geotextile with a 2’ thick layer of clean surface cover to act as a barrier to
direct contact and institutional control of the Site under an AUL.
Furthermore, as part of the Phase III, AEG completed a Method 3 Risk Assessment to
evaluate the only group identified who would have future direct contact with
contaminated soils beneath the cap. These receptors included Construction and Utility
workers. The result of the Method III showed that Significant Risk still exists for this
receptor group. However, the AUL will implement measures to prevent direct exposure
including use of particulate respirators and chemical resistant gloves, in addition to a soil
management plan that would outline procedures to manage fugitive dust. Furthermore,
during any Construction/Utility work conducted in the future, the park would be closed to
public use until the cap was repaired to its original configuration and condition.
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Phase III MCP Report
Margin Street Park, Beverly, MA
5
AEG Project # 1667
February 2007
COMPLETION STATEMENT AND LSP OPINION
This Phase III Report has been completed in accordance with 310 CMR 40.0000 of the
MCP. At this time, a remedial action rendering a level of No Significant Risk has been
evaluated and selected based upon specific criteria of the MCP. Furthermore, a Method 3
has been completed, which shows that, when in place, the remedial action maintains a
condition of No Significant Risk.
AEG’s office is located at 124 Mt. Auburn Street, Suite 200N, Cambridge, Massachusetts
02138. AEG can be contacted at (617) 492-6500.
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