August 24, 2017

Mr. Nick Hodgkins

Maine Department of Environmental Protection

17 State House Station

Augusta, Maine 04333

Subject: Phase II Environmental Site Assessment Scope of Work

Portland Bayside Parcel 3

178 Kennebec Street, Portland, Maine

Dear Mr. Hodgkins:

Credere Associates, LLC (Credere) was retained by the Maine Department of Environmental

Protection (DEP) to prepare this Phase II Environmental Site Assessment (ESA) Scope of Work

(SOW) for the property located at 178 Kennebec Street in Portland, Maine (Site).

1. SITE DESCRIPTION AND HISTORY

Site Description

The 0.2217-acre Site is developed as an unpaved parking lot currently used for the City of Portland

Public Works Department (DPW) vehicles, such as trucks and plows. Railroad tracks remain at

the Site indicating the location of the former railway.

Site History

In 1851, the Site was within the tidal zone of Back Cove (i.e., submerged) and the York and

Cumberland railroad line that crossed the Site was elevated on a bridge. Subsequently, the Site

and surrounding area was filled, and the Site occupied by Portland and Rochester Railroad line

dating back to at least 1871. At the time, the Site was depicted at the edge of the tidal zone. By

1886, Back Cove had been filled further north, the Site was developed with an engine repair house

associated with the Boston and Maine Railroad, and the surrounding area was residentially

developed. Other surrounding properties were developed with a laundry facility (New Systems

Landry facility) to the south beginning in the 1920s and coal fuel companies by 1939 to the east.

By 1949, the Site engine house was removed, but the railroad tracks remained. Through 1980,

surrounding properties were developed with the Portland DPW garage to the east, post office to

the west, post office garage to the north, and other various commercial/industrial occupants. It is

not known when active use of the rail line ceased; however, the Site was likely used for parking

or material storage since approximately 1970. It is reported New System Laundry did not begin

dry cleaning operations until 1978 and continued to 2013; however, the duration of operation as a

dry cleaner in recent history is not known.

Phase II Environmental Site Assessment Scope of Work

Portland Bayside Parcel 3

178 Kennebec Street, Portland, Maine August 24, 2017

CREDERE ASSOCIATES, LLC

2. PRIOR ENVIRONMENTAL REPORTS

Phase I Environmental Site Assessment, Credere, April 5, 2017

Credere prepared a Phase I ESA for the City of Portland dated April 5, 2017, for the purpose of

identifying recognized environmental conditions (RECs) as defined by the ASTM E 1527-13

standard associated with the Site. This Phase I ESA identified the following REC and other

environmental finding that did not rise to the level of a REC:

• REC #1 – Soil impacts associated with historical filling of the Site and railroad

development

• Environmental Finding #1 – Upgradient New Systems Laundry to the south

Supplemental Reconnaissance, August 1, 2017

On August 1, 2017, Credere completed a supplemental reconnaissance with the Maine DEP and

Kathy Alves of the City of Portland DPW. No additional items of concern were noted since the

April 2017 Phase I ESA.

3. CONCEPTUAL SITE MODEL

3.1 Physical Setting

Topography

Based on Credere’s Site observations and the United States Geological Survey (USGS)

Topographic Map of the Portland West Quadrangle, Maine, the Site is located approximately 12

feet above mean seal level (AMSL), and topography at the Site is generally flat with the local area

sloping gently north towards Back Cove.

Geology

Surficial Geology

According to the Maine Geological Survey (MGS) map, Surficial Geology of the Portland West

Quadrangle, Maine, the Site is mapped in an area of the Presumpscot Formation, which consists

of silt, clay, and minor sand deposited on the sea floor during the late-glacial marine submergence.

The Site was previously submerged and part of the tidal zone of Back Cove dating back to

approximately 1851, and the Site was filled prior to the 1880s to bring it above sea level. Previous

investigations in the local area have indicated urban fill to be present in varying thicknesses at the

surface with thickness increasing between Portland Street to the south and Kennebec Street

adjoining the Site to the north.

According to an Environmental Assessment performed by Tewhey Associates of adjoining and

nearby properties, surficial geology in the vicinity of the Site includes a layer of granular fill

material overlying the native soils. The thickness of the fill material increases to the north towards

Kennebec Street, with an average fill thickness previously observed to range from approximately

2 to 9 feet in adjoining and nearby properties.

Phase II Environmental Site Assessment Scope of Work

Portland Bayside Parcel 3

178 Kennebec Street, Portland, Maine August 24, 2017

CREDERE ASSOCIATES, LLC

Bedrock Geology

According to the MGS map, Bedrock Geology of the Portland West Quadrangle, Maine, the Site

is underlain by the Eliot Formation, which comprises Silurian to Ordovician fine-grained quartz-

plagioclase-biotite phyllite with abundant carbonate or calc-silicate mineral depending on the

metamorphic grade. The John’s Point Fault is located just south of the Site.

Hydrology

The Site is located within the surficial drainage basin of Back Cove, located approximately 0.5

miles north of the Site. Back Cove flows directly into the Atlantic Ocean, connected on the east

side. According to prior investigations performed at the Site, groundwater is approximately 10

feet below ground surface (bgs).

According to the Significant Sand and Gravel Aquifers of the Portland West Quadrangle, the Site

is not located within a significant sand and gravel aquifer.

For purposes of assessing potential environmental impacts from offsite sources, groundwater in

the area was inferred to flow generally north.

3.2 Source Areas & Current Contaminants of Concern

Based on the results of prior investigations and the findings of the April 2017 Phase I ESA, the

current source areas and contaminants of concern (COCs) include the following.

Source Areas

The following source areas were identified at the Site based on the previous investigations and the

findings of the April 2017 Phase I ESA:

• Urban fill throughout the Site

• Offsite upgradient former dry cleaner to the south (New Systems Laundry) and comingled

petroleum in groundwater

COCs

Based on the above source areas, associated current COCs include the following:

• Polycyclic aromatic hydrocarbons (PAHs)

• Lead

• Volatile organic compounds (VOCs)

• Extractable petroleum hydrocarbons (EPH)

3.3 Nature and Extent

The inferred extent of COCs based on currently available data is as follows:

Phase II Environmental Site Assessment Scope of Work

Portland Bayside Parcel 3

178 Kennebec Street, Portland, Maine August 24, 2017

CREDERE ASSOCIATES, LLC

PAHs and Lead

PAHs and lead were detected at varying concentrations in random locations of nearby and

adjoining properties, which indicates the heterogeneity of the fill in the Site vicinity. The Site has

not been assessed to date and analytical data and subsurface observations for the Site remain data

gaps. The concentrations of PAHs and lead are attributed to the presence of urban fill associated

with the filling of the Back Cove area; therefore, PAHs and lead are considered ubiquitous in the

fill interval at the Site.

VOCs and EPH

A subsurface investigation in 1990 indicated the presence of tetrachloroethylene (PCE) and

petroleum in groundwater at the upgradient to the south New System Laundry facility. PCE

concentrations in shallow groundwater were 15 micrograms per liter (µg/L) and were below the

laboratory reporting limits in the deeper aquifer above bedrock (46 feet bgs). Petroleum

concentrations (unknown method) presumably associated with the former fuel oil underground

storage tank (UST) were between 17,000 and 28,000 µg/L. The downgradient extent of PCE in

groundwater was not assessed; therefore, VOCs are considered a COC for subsurface soils and

primarily for groundwater at the Site. Assessment for migration of PCE or other chlorinated

volatile organic compounds (CVOCs) and petroleum onto the Site remains a data gap.

4. SCOPE OF WORK

Based on the identified data gaps in the above conceptual Site model, Credere has prepared the

scope of work provided in the attached Table 1.

Credere appreciates the opportunity to work with you on this project. Please do not hesitate to

contact me at (207) 828-1272 ext. 15 if you have any questions.

Sincerely,

Credere Associates, LLC

Allison Drouin, PG, CG Theresa Patten, PE

Project Manager/Geologist President

Attachment: Figure 1 – Proposed Sample Locations

Table 1 – Scope of Work

AA

A

A

!?

!?

!?

!?

!? !A

PARRIS STREET

THE SITE178 KENNEBEC STREET

KENNEBEC STREET

57 BRATTLE STREETPORTLAND PUBLIC WORKS PARKING

171 KENNEBEC STREETPOST OFFICE

158 KENNEBEC STREETPORTLAND PUBLIC WORKS PARKING

111 FOREST AVENUEPOST OFFICE

181 FOREST AVENUEPORTLAND PUBLIC WORKS PARKING

200 KENNEBEC STREETVANDELAY INDUSTRIES LLC

UNDEVELOPED

195 KENNEBEC STREETVANDELAY INDUSTRIES LLCFIRESTONE CENTURY TIRE COMPANY

FORMER DRY CLEANERS

PRES

UMED

GRO

UNDW

ATER

FLOW

DIR

ECTIO

N

BRATTLE STREET

82 HANOVER STREETPORTLAND PUBLIC WORKS GARAGE

MW-1

MW-2MW-4

MW-3

SB-6

SB-5

SB-4SB-3

SB-2

SB-1/MW-1

P:\17001390 Portland Bayside Phase I ESAData Source: Ortho Image: Google Maps (2012). Parcels: City of Portland (2012) Tax Map 323, 322, and 311.

PROJECT:DATE:

CHECKED BY:DRAWN BY: 8/4/2017

13001211

PORTLAND BAYSIDE178 KENNEBEC STREET

PORTLAND, MAINE 04103

p776 MAIN STREETWESTBROOK, MAINETel. 207.828.1272 Fax 207.887.1051WWW.CREDERELLC.COM

Credere Associates, LLCFIGURE 1

PROPOSED SAMPLE LOCATIONS

CRED

ERE

SAFASD

NOTES:1. EXISTING CONDITIONS FEATURES SHOWS ON THIS PLAN ARE APPROXIMATE AND ARE BASED ON INFORMATION OBTAINED FROM THE CITY OF PORTLAND ONLINE GIS DATA AND SITE RECONNAISSANCE PERFORMED ON MARCH 23, 2017 ANDAUGUST 1, 2017.2. AERIAL IMAGERY IS SLIGHTLY ASKEW, THEREFORE PARCEL BOUNDARIES MAY OVERLAP WITH BUILDING ROOFTOPS.

0 25 5012.5 FEET1 INCH = 25 FEET

!A PROPOSED SOIL BORING/MONITORING WELL LOCATION!? PROPOSED SOIL BORING LOCATION

A 1980 MONITORING WELLSSITE BOUNDARYPARCEL BOUNDARY

Media to be Collected Proposed Sample IDs QA/QC SamplesBoring/Screen Target

DepthSample Rationale

Sample Depth

(feet bgs)

Field Analysis/

ObservationsAnalytical Methods

To assess impacts associated with urban fill in accessible soil and

observe fill thickness 0-2

PAHs (EPA Method 8270D)

Lead (EPA Method 6020A)

To assess impacts associated with upgradient former dry cleaner

Greatest observed

contamination or groundwater

interface

VOCs (EPA Method 8260C)

EPH (MADEP EPH-04-1.1)

SB-2

SB-3

SB-4

SB-5

SB-6

Gro

un

dw

ate

r

MW-11 field duplicate

Trip blank (1 per cooler)

At least 5 feet past

groundwater interfaceTo assess impacts associated with upgradient former dry cleaner Screened interval

Visual, olfactory,

temperature, DO, pH, ORP,

specific conductivity,

turbidity

VOCs (EPA Method 8260C)

EPH (MADEP EPH-04-1.1)

Notes:

1 - If evidence of petroleum contamination is identified through odor or obviously saturated soils, oleophilic dye tests will be utilized to assess the presence of petroleum.

PID - photoionization detector ORP - oxidation-reduction potential VOCs - volatile organic compounds

bgs - below ground surface PAHs - polycyclic aromatic hydrocarbons EPH - extractable petroleum hydrocarbons

DO - dissolved oxygen

Table 1: Scope of Work

Portland Bayside Parcel 3

178 Kennebec Street, Portland, Maine

Soil 1 field duplicate

Trip blank (1 per cooler)

SB-1

At least 5 feet into native

soil

To assess impacts associated with urban fill in accessible soil and

observe fill thickness 0-2

PAHs (EPA Method 8270D)

Lead (EPA Method 6020A)

At least 5 feet past

groundwater interface for

monitoring well installation

or 5 feet into native soil

PID screening

Oleophilic dye tests1

Visual

Olfactory