Office of Solid Waste and EPA-542-R-11-010
Emergency Response January 2012
(5102G) www.epa.gov/tio
www.clu-in.org/optimization
Optimization Review
Palermo Wellfield Superfund Site
City of Tumwater, Thurston County, Washington
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OPTIMIZATION REVIEW
PALERMO WELLFIELD SUPERFUND SITE
CITY OF TUMWATER, THURSTON COUNTY, WASHINGTON
Report of the Optimization Review
Site Visit Conducted at the Palermo Wellfield Superfund Site on
August 25, 2011
December 14, 2011
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EXECUTIVE SUMMARY
Optimization Background
U.S. Environmental Protection Agency's (USEPA) working definition of optimization as of December
2011 is as follows:
"A systematic site review by a team of independent technical experts, at any phase of a cleanup process,
to identify opportunities to improve remedy protectiveness, effectiveness and cost efficiency, and to
facilitate progress toward completion of site work. "
An optimization review considers the goals of the remedy, available site data, conceptual site model
(CSM), remedy performance, protectiveness, cost-effectiveness, and closure strategy. A strong interest in
sustainability has also developed in the private sector and within Federal, State, and Municipal
governments. Consistent with this interest, optimization now routinely considers green remediation and
environmental footprint reduction during optimization reviews. An optimization review includes
reviewing site documents, interviewing site stakeholders, potentially visiting the site for one day, and
compiling a report that includes recommendations in the following categories:
• Protectiveness
• Cost-effectiveness
• Technical improvement
• Site closure
• Environmental footprint reduction
The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed prior to implementation of the recommendation. Note that the recommendations are based on an
independent review, and represent the opinions of the review team. These recommendations do not
constitute requirements for future action, but rather are provided for consideration by the Region and
other site stakeholders. Also note that while the recommendations may provide some details to consider
during implementation, the recommendations are not meant to replace other, more comprehensive,
planning documents such as work plans, sampling plans, and quality assurance project plans (QAPP).
Site-Specific Background
The Palermo Wellfield Superfund Site (Site) is located near Interstate Highway 5 and Trosper Road in
Tumwater, Washington. The Site includes a City-operated water-supply wellfield and an adjacent
residential neighborhood in the Deschutes River Valley (sometimes referenced in site documents as the
Palermo Valley), as well as upland source areas including the current Washington State Department of
Transportation (WSDOT) Materials Testing Laboratory (MTL), a former WSDOT MTL, and the
Southgate Dry Cleaners business. Trichloroethene (TCE) was detected at the wellfield in 1993.
Subsequent investigations identified a TCE groundwater plume over 3,000 feet (ft) long and 600 ft wide,
and a smaller tetrachloroethene (PCE) plume near the Southgate Dry Cleaners site.
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The Site remedy for groundwater includes capture of contaminated groundwater at the Palermo Wellfield
with air stripping to reduce the levels of TCE and PCE below maximum contaminant levels (MCL). The
air strippers have been in operation since 1999.
Additionally, a soil vapor extraction system (SVE) was operated from 1998 to 2000 at the Southgate Dry
Cleaners site to reduce the levels of PCE near this source area.
Finally, a French drain system has been installed at the western edge of the Palermo neighborhood to
prevent surface discharge of contaminated groundwater to home crawlspaces and to mitigate the potential
for indoor air exposure risks at the homes in the neighborhood. Groundwater collected in the French drain
system is treated through aeration in a small lagoon and discharged to a ditch that flows to the Deschutes
River.
Summary of Conceptual Site Model
Figure 1 is a cross-section illustration that summarizes the CSM. Volatile organic compound (VOC)
contamination released at the surface and/or in the shallow subsurface from the Southgate Dry Cleaners
and both the current and former WSDOT MTL facilities has impacted groundwater at the Site. The soils
are relatively permeable (described as sands) and low in organic carbon. In addition, the releases in some
cases may have occurred approximately 25 years before remedial investigation (RI) sampling occurred.
These factors contributed to relatively low soil concentrations observed during the RI and may have
resulted in relatively weak continuing sources of dissolved groundwater contamination in 2010 at these
previously identified sources. The relatively high groundwater flow rates and low organic carbon have
contributed to contaminant flushing over the period of three to four decades from the time of the original
releases until present. As a result, the majority of contamination associated with the original releases
appears to have migrated away from the source areas and is now present in the vicinity of the Palermo
neighborhood. However, one or more of the historic source areas may be continuing to impact
groundwater.
The known extent of the VOC groundwater plume is approximately 3,000 ft long and includes the
Palermo Wellfield. The fate of contaminated groundwater includes surface expression as seeps in the
vicinity of the Palermo neighborhood, capture by the subdrain system (constructed as a French drain),
extraction by the Palermo Wellfield, or potentially migration beyond the Palermo neighborhood and
Palermo Wellfield. Contaminant migration pathways begin at the water table near the source areas and
gradually migrate deeper as a result of regional pumping and recharge. Due the relatively eastern location
of the main PCE source area (Southgate Dry Cleaners), it is likely that the PCE has remained sufficiently
shallow to be captured by the subdrain system as reflected by the PCE concentrations in the subdrain and
the absence of PCE detections in groundwater downgradient of the subdrain. PCE concentrations have
been decreasing in the subdrain because the PCE source was mostly removed and the PCE is being
flushed from the aquifer. TCE contamination, which started migrating from sources further west, has had
the opportunity to migrate slightly deeper and is more dispersed. The TCE plume core likely migrates
under the subdrain. The removal of water from the subdrain and the surface expression of seeps due to the
abrupt change in regional topography result in an upward gradient in the valley such that some of the
deeper TCE migrates closer to the surface in the Palermo neighborhood and some is extracted by the
Palermo Wellfield. Shallow groundwater contaminated with TCE and PCE and/or shallow groundwater
discharging to the surface represent potential vapor intrusion (VI) exposures for residents in the Palermo
neighborhood north of the Palermo Wellfield.
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Summary of Findings
Based on a review of the information provided to the optimization team, the Site visit conducted on
August 25, 2011, and interviews with persons knowledgeable about the Site, the following main findings
have been identified:
• The definition of the groundwater plume is incomplete.
• Plume capture by the subdrain and wellfield is likely not complete.
• VI remains a concern and additional information is needed.
• There is insufficient information to determine if historic sources continue to be ongoing sources
of contamination.
Summary of Recommendations
Recommendations are provided to improve remedy effectiveness, reduce cost, provide technical
improvement, and assist with accelerating site closure. The recommendations in these areas are as
follows:
Improving effectiveness - sample additional existing and new wells to improve plume delineation and the
CSM, update the capture zone evaluation based on the new information, update and improve the indoor
air sampling in the Palermo neighborhood, install vapor mitigation systems as appropriate, evaluate the
feasibility and costs of improving the subdrain extraction rate and influence, evaluate the effectiveness of
the historic SVE system at remediating soils, and formalize an agreement with City of Tumwater for
wellfield operation.
Reducing cost - refine the long-term monitoring (LTM) program after completion of additional
investigation work. Cost reductions will not occur in the immediate future but rather after full delineation
is attained and concentration trends are established.
Technical improvement - improve the presentation of data in reports and manage data electronically.
Site closure - update the official site remedy description after completion of the other recommendations.
No opportunities were identified for meaningful reduction of the remedy environmental footprint.
in
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NOTICE
Work described herein was performed by Tetra Tech GEO for the U.S. Environmental Protection Agency
(USEPA). Work conducted by Tetra Tech GEO, including preparation of this report, was performed
underwork Assignment 1-58 of USEPA contract EP-W-07-078 with Tetra Tech EM, Inc., Chicago,
Illinois. Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
IV
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PREFACE
This report was prepared as part of a national strategy to expand Superfund optimization from remedial
investigation to site completion implemented by the United States Environmental Protection Agency
(USEPA) Office of Superfund Remediation and Technology Innovation (OSRTI). The project contacts
are as follows:
Organization
Key Contact
Contact Information
USEPA Office of Superfund
Remediation and Technology
Innovation
(OSRTI)
Kathy Yager
USEPA
Technology Innovation and Field Services
Division
11 Technology Drive (ECA/OEME)
North Chelmsford, MA 01863
yager.kathleen@epa.gov
phone:617-918-8362
USEPA Office of Superfund
Remediation and Technology
Innovation
(OSRTI)
Stephen Dyment
USEPA
Technology Innovation and Field Services
Division
1200 Pennsylvania Ave., NW (5203P)
Washington, DC 20460
dyment. stephen@epa. gov
Phone: 703-603-9903
Tetra Tech EM, Inc.
(Contractor to USEPA)
Jody Edwards, P.G.
Tetra Tech EM Inc.
1881 Campus Commons Drive, Suite 200
Reston,VA20191
iody.edwards@tetratech.com
phone: 802-288-9485
Tetra Tech GEO
(Subcontractor to Tetra Tech EM,
Inc.)
Doug Sutton, PhD,
P.E.
Tetra Tech GEO
2 Paragon Way
Freehold, NJ 07728
phone: 732-409-0344
doug.sutton@tetratech.com
v
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LIST OF ACRONYMS
micrograms per liter
micrograms per cubic meter
above mean sea level
applicable or relevant and appropriate requirements
below ground surface
best management practice
Comprehensive Environmental Response, Compensation, and Liability
Act
cubic feet per minute
chemical of concern
compound specific isotope analysis
conceptual site model
Environmental Data Resources Inc
Explanation of Significant Difference
feasibility study
feet
feet squared
cubic feet
Five Year Review
granular activated carbon
gallons per minute
human health risk assessment
hazard index
horsepower
Institutional controls
hydraulic conductivity
long term monitoring
maximum contaminant limit
milligrams per kilogram
Model Toxics Control Act
materials testing laboratory
monitoring well
National Priorities List
Office of Superfund Remediation and Technology Innovation
operable unit
pump and treat
tetrachloroethylene (perchloroethylene)
Potentially Responsible Party
polyvinyl chloride
(ig/m3
amsl
ARARs
bgs
BMP
CERCLA
cfm
coc
CSIA
CSM
EDR
BSD
FS
ft
ft2
ft3
FYR
GAC
gpm
HHRA
HI
HP
1C
K
LTM
MCL
mg/kg
MTCA
MTL
MW
NPL
OSRTI
OU
P&T
PCE
PRP
PVC
VI
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QA
QAPP
RA
RAO
RG
RI
ROD
RSE
SIM
SVE
TCE
USEPA
UST
VI
VOC
WSDOE
WSDOT
quality assurance
Quality Assurance Project Plan
Remedial Action
remedial action objective
remediation goal
remedial investigation
Record of Decision
remedial system evaluation
Selected Ion Monitoring
soil vapor extraction
Trichloroethylene
United States Environmental Protection Agency
underground storage tank
vapor intrusion
volatile organic compound
Washington State Department of Ecology
Washington State Department of Transportation
vn
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TABLE OF CONTENTS
EXECUTIVE SUMMARY i
NOTICE iv
PREFACE v
LIST OF ACRONYMS vi
TABLE OF CONTENTS vii
1.0 INTRODUCTION 1
1.1 PURPOSE 1
1.2 TEAM COMPOSITION 2
1.3 DOCUMENTS REVIEWED 2
1.4 QUALITY ASSURANCE 3
1.5 PERSONS CONTACTED 3
2.0 SITE BACKGROUND 5
2.1 LOCATION 5
2.2 SITE HISTORY 5
2.2.1 HISTORIC LAND USE AND OPERATIONS 5
2.2.2 CHRONOLOGY OF ENFORCEMENT AND REMEDIAL ACTIVITIES 5
2.3 POTENTIAL HUMAN AND ECOLOGICAL RECEPTORS 7
2.4 EXISTING DATA AND INFORMATION 7
2.4.1 SOURCES OF CONTAMINATION 8
2.4.2 GEOLOGY SETTING AND HYDROGEOLOGY 9
2.4.3 SOIL CONTAMINATION 9
2.4.4 SOIL VAPOR OR INDOOR AIR CONTAMINATION 11
2.4.5 GROUNDWATER CONTAMINATION 12
2.4.6 SURFACE WATER CONTAMINATION 13
3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES 15
3.1 REMEDY AND REMEDY COMPONENTS 15
3.1.1 WELLHEAD TREATMENT AIR STRIPPERS 15
3.1.2 SUBDRAIN AND TREATMENT LAGOON 15
3.1.3 STANDING WATER EVALUATION 16
3.1.4 SVE 16
3.1.5 LONG-TERM GROUNDWATER MONITORING 16
3.1.6 MONITORING OF SUBDRAIN AND LAGOON PERFORMANCE 16
3.1.7 PUBLIC NOTICE OF CONTAMINATED GROUNDWATER 17
3.2 RAOs AND STANDARDS 17
3.3 PERFORMANCE MONITORING PROGRAMS 18
4.0 CONCEPTUAL SITEMODEL 19
4.1 CSM OVERVIEW 19
Vlll
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4.2 CSM DETAILS AND EXPLANATION 20
4.2.1 TCE AND PCE SOURCE AREAS, GROUND WATER PLUME MORPHOLOGY 20
4.2.2 SHALLOW GROUND WATER AND VI 21
4.2.3 HISTORICAL INFORMATION AND CSM ELEMENTS 21
4.3 DATA GAPS 22
4.4 IMPLICATIONS FOR REMEDIAL STRATEGY 22
5.0 FINDINGS 23
5.1 SOURCES 23
5.1.1 CONNECTION OF PLUMES TO SOURCES 23
5.1.2 SVE EFFECTIVENESS 23
5.2 GROUNDWATER 23
5.2.1 PLUME DELINEATION 23
5.2.2 PLUME CAPTURE 24
5.2.3 GROUNDWATER CONTAMINANT CONCENTRATIONS 26
5.3 SHALLOW GROUNDWATER AND VI 26
5.3.1 GROUNDWATER DISCHARGE TO SURFACE WATER 26
5.3.2 VIPOTENTIAL AND AIR QUALITY 27
5.4 TREATMENT SYSTEM COMPONENT PERFORMANCE 28
5.4.1 PALERMO WELLFIELD AIR STRIPPERS 28
5.4.2 SUBDRAIN SYSTEM TREATMENT LAGOON 28
5.5 REGULATORY COMPLIANCE 28
5.6 COMPONENTS OR PROCESSES THAT ACCOUNT FOR MAJORITY OF ANNUAL COSTS 28
5.7 APPROXIMATE ENVIRONMENTAL FOOTPRINTS ASSOCIATED WITH REMEDY 28
5.8 SAFETY RECORD 29
6.0 RECOMMENDATIONS 30
6.1 RECOMMENDATIONS TO IMPROVE EFFECTIVENESS 30
6.1.1 EXPAND GROUNDWATER SAMPLING TO BETTER DEFINE THE PLUMES AND TO
INFORM AN UPDATED CAPTURE-ZONE EVALUATION 30
6.1.2 UPDATE CAPTURE-ZONE ANALYSIS 32
6.1.3 RENEW AND IMPROVE INDOOR AIR SAMPLING PROGRAM IN PALERMO
NEIGHBORHOOD 32
6.1.4 INSTALL MITIGATION SYSTEMS IF/AS NEEDED AT NEIGHBORHOOD HOUSES ... 34
6.1.5 EVALUATE OPTIONS AND PRACTICABILITY FOR LOWERING THE WATER TABLE
AT THE BLUFF AND THROUGHOUT THE PALERMO NEIGHBORHOOD 35
6.1.6 ASSESS VIAT SOUTHGATE SHOPPING CENTER 36
6.1.7 EVALUATE SVE EFFECTIVENESS AND IMPLEMENT CONTROLS AS NEEDED 37
6.1.8 MAKE AN AGREEMENT WITH THE CITY FOR CONTINUED OPERATION OF THE
PALERMO WELLFIELD IN A MANNER NEEDED TO ENSURE CAPTURE 37
6.2 RECOMMENDATIONS TO REDUCE COSTS 38
6.2.1 REDUCE SAMPLING FREQUENCY AT SELECT MONITORING WELLS 38
6.3 RECOMMENDATIONS FOR TECHNICAL IMPROVEMENT 38
6.3.1 MONITORING REPORTS 39
6.3.2 WELL-FLOW REPORTING SYSTEM 39
6.3.3 DATA MANAGEMENT SYSTEM 39
6.4 CONSIDERATIONS FOR GAINING SITE CLOSE OUT 39
IX
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6.4.1 SUGGESTED CLOSURE STRATEGY 39
6.4.2 MODIFY THE REMEDY 40
6.5 RECOMMENDATIONS RELATED TO GREEN REMEDIATION 40
6.6 SUGGESTED APPROACH TO IMPLEMENTING RECOMMENDATIONS 40
List of Tables
Table 6-1. Cost Summary Table
List of Figures
Figure 1. Cross Section Illustration of Site Conceptual Model
Attachments
Attachment A: Figures from Existing Site Reports
Attachment B: Chart of Historic VI Sampling Results
Attachment C: PCE/TCE Trends in Monitoring Wells
Attachment D: PCE/TCE Trends in the Subdrain
Attachment E: Location of Pertinent Surface Features
Attachment F: Photolog
Attachment G: EDR Report
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1.0 INTRODUCTION
1.1 PURPOSE
During fiscal years 2000 and 2001 independent reviews called Remediation System Evaluations (RSEs)
were conducted at 20 operating Fund-lead pump and treat (P&T) sites (i.e., those sites with P&T systems
funded and managed by Superfund and the States). Due to the opportunities for system optimization that
arose from those RSEs, U.S. Environmental Protection Agency (USEPA) Office of Superfund
Remediation and Technology Innovation (OSRTI) has incorporated RSEs into a larger post-construction
complete strategy for Fund-lead remedies as documented in OSWER Directive No. 9283.1-25, Action
Plan for Ground Water Remedy Optimization. Concurrently, USEPA developed and applied the Triad
Approach to optimize site characterization and development of a conceptual site model (CSM). USEPA
has since expanded the definition of optimization to encompass investigation stage optimization using
Triad Approach best management practices (BMP), optimization during design, and RSEs. USEPA's
working definition of optimization as of December 2011 is as follows:
"A systematic site review by a team of independent technical experts, at any phase of a
cleanup process, to identify opportunities to improve remedy protectiveness,
effectiveness, and cost efficiency, and to facilitate progress toward site completion. "
As stated in the definition, optimization refers to a "systematic site review," indicating that the site as a
whole is often considered in the review. Optimization can be applied to a specific aspect of the remedy
(e.g., focus on long-term monitoring [LTM] optimization or focus on one particular operable unit [OU]),
but other site or remedy components are still considered to the degree that they affect the focus of the
optimization. An optimization review considers the goals of the remedy, available site data, CSM, remedy
performance, protectiveness, cost-effectiveness, and closure strategy. A strong interest in sustainability
has also developed in the private sector and within Federal, State, and Municipal governments. Consistent
with this interest, OSRTI has developed a Green Remediation Primer (http://cluin.org/greenremediation/).
and now routinely considers green remediation and environmental footprint reduction during optimization
reviews. The optimization review includes reviewing site documents, potentially visiting the site for one
day, and compiling a report that includes recommendations in the following categories:
• Protectiveness
• Cost-effectiveness
• Technical improvement
• Site closure
• Environmental footprint reduction
The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed prior to implementation of the recommendation. Note that the recommendations are based on an
independent evaluation, and represent the opinions of the review team. These recommendations do not
constitute requirements for future action, but rather are provided for consideration by the Region and
other site stakeholders. Also note that while the recommendations may provide some details to consider
during implementation, the recommendations are not meant to replace other, more comprehensive,
planning documents such as work plans, sampling plans, and quality assurance project plans (QAPP).
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The national optimization strategy includes a system for tracking consideration and implementation of the
optimization recommendations and includes a provision for follow-up technical assistance from the
optimization team as mutually agreed upon by the site management team and USEPA OSRTI.
The Palermo Wellfield Superfund Site (Site) is located near Interstate Highway 5 and Trosper Road in
Tumwater, Washington. The Site includes a City-operated water-supply wellfield and an adjacent
residential neighborhood in the Deschutes River Valley (sometimes referenced in site documents as the
Palermo Valley), as well as upland source areas including the current Washington State Department of
Transportation (WSDOT) Materials Testing Laboratory (MTL), a former WSDOT MTL, and the
Southgate Dry Cleaners business. Trichloroethene (TCE) was detected in the City water supply at the
wellfield in 1993. Subsequent investigations identified a TCE groundwater plume over 3,000 feet (ft)
long and 600 ft wide, and a smaller tetrachloroethene (PCE) plume near the Southgate Dry Cleaners site.
USEPA Region 10 nominated the Site for an optimization review due an interest in updating the CSM
and concerns regarding plume migration control and the potential for vapor intrusion (VI).
1.2 TEAM COMPOSITION
The optimization team consisted of the following individuals:
Name
Steve Dyment
Greg Council
Tim Costello
Affiliation
USEPA HQ/OSRTI
Tetra Tech GEO
Tetra Tech GEO
Phone
703-603-9903
770-619-9950
916-853-4584
Email
dy ment. stephen@epa. gov
greg.council@tetratech.com
tim.costello@tetratech.com
In addition, Doug Sutton from Tetra Tech GEO assisted with project direction, report preparation/review,
and evaluation of the environmental footprint of remedial components.
1.3 DOCUMENTS REVIEWED
The following documents were reviewed. The reader is directed to these documents for additional site
information that is not provided in this report.
Remedial Action Construction Documentation Subdrain System and Treatment Lagoon (URS
Greiner, Inc. - March 6, 2011)
Action Memorandum for a Removal Action (USEPA - June 27, 1997)
Soil Vapor Extraction System Operation, Decommissioning, and Confirmation Sampling (URS
Corporation - August 11, 2000)
Final Trip Report (URS Greiner, Inc. - October 2001)
Final 2010 Annual Groundwater Long-Term Monitoring Report (Parametrix - April 2011)
Final Feasibility Study (URS Greiner, Inc. - May 1999)
Final Remedial Investigation (URS Greiner, Inc. - June 1999)
Technical Memorandum Modeling of Site Characteristics (URS Greiner, Inc. - June 1999)
First Five Year Review Report (URS Greiner, Inc. - September 2003)
Final Second Five Year Review Report (Parametrix - September 2008)
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• Final Record of Decision (USEPA - October 1999)
• Expert Report ofDimitri Vlassopoulos, Ph.D (Dimitri Vlassopoulos - May 2006)
• Brewery City Pizza Removal Assessment (Ecology & Environment, Inc. - August 30, 1997)
• Liability Status of Chevron at the Palermo Superfund Site (USEPA - October 11, 2002)
• City of Tumwater 2010 Water System Plan (HDR - April 2011)
• Underground Storage Tank Closure and Independent Remedial Action Report (July 1, 1996)
Also, historical aerial photographs and topographic maps were obtained and reviewed during this review.
Those materials, which were obtained from Environmental Data Resources Inc (EDR), are provided in
Attachment G.
1.4 QUALITY ASSURANCE
This optimization review utilizes existing environmental data to interpret the CSM, evaluate remedy
performance, and make recommendations to improve the remedy. The quality of the existing data is
evaluated by the optimization team prior to using the data for these purposes. The evaluation for data
quality includes a brief review of how the data were collected and managed (where practical, the site
QAPP is considered), the consistency of the data with other site data, and the use of the data in the
optimization review. Data that are of suspect quality are either not used as part of the optimization review
or are used with the quality concerns noted. Where appropriate, this report provides recommendations
made to improve data quality.
1.5 PERSONS CONTACTED
A stakeholders meeting was held on August 25, 2011, at the offices of Washington State Department of
Ecology (WSDOE) in Lacey, Washington. In addition to the optimization team, the following persons
were present for the stakeholders meeting:
Name
Claire Hong
Marcia Bailey
Kira Lynch
Bernie Zavala
Lara Linde
Norm Payton
Rico Baroga
Mike Stephens
Scott MacDonald
Mike Hutchinson
Affiliation
USEPA Region 10 (RPM)
USEPA Region 10
USEPA Region 10
USEPA Region 10
Parametrix (USEPA contractor)
WSDOT
WSDOT
WSDOT
GeoEngineers (WSDOT contractor)
GeoEngineers (WSDOT contractor)
Email Address
hong.claire@epa.gov
bailey.marcia@epa.gov
lynch .kira@epa. gov
zavala.bernie@epa.gov
llinde@parametrix.com
pavtonn@wsdot.wa.gov
barogar@wsdot.wa.gov
stephem@wsdot.wa.gov
smacdonald@geoengineers.com
mhutchinson@geoengineers.com
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Guy Barrett
Barbara Trejo
WSDOE
Washington State Department of Health
gbar461@ecy.wa.gov
barbara.trej o@doh.wa.gov
After the stakeholders meeting, the entire group toured the site. A portion of the Site tour was conducted
at the Palermo Wellfield property. For that portion of the tour, three City of Tumwater employees
participated: Dan Smith (Water Resources Program Manager; desmith@ci.tumwater.wa.us'). Dennis Ash,
and Steve Craig.
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2.0 SITE BACKGROUND
2.1 LOCATION
The Site is located near Interstate Highway 5 and Trosper Road in Tumwater, Thurston County,
Washington. Tumwater is located about 60 miles south of Seattle in the Puget Sound Basin of western
Washington. The Site includes a City-operated water-supply wellfield and an adjacent residential
neighborhood in the Deschutes River Valley (sometimes referenced in site documents as Palermo Valley),
as well as upland source areas including the (current) WSDOT MTL, a former WSDOT MTL, and the
Southgate Dry Cleaners business. TCE was detected in the City water supply in 1993 at a level exceeding
the maximum contaminant level (MCL). Subsequent investigations identified a TCE groundwater plume
over 3,000 ft long and 600 ft wide, and a smaller PCE plume near the Southgate Dry Cleaners site. The
western (upgradient) end of the TCE plume is near the intersection of Trosper Road and Littlerock Road,
about 800 ft south of Barnes Lake. The TCE plume extends to the east northeast, across the Palermo Bluff
(i.e., the steep topographic drop into the Deschutes River Valley), and underneath the Palermo
neighborhood just west of the Tumwater Valley Golf Course. The City's Palermo Wellfield is located
south of and adjacent to the Palermo neighborhood (Attachment A: Exhibit A-l).
2.2 SITE HISTORY
2.2.1 HISTORIC LAND USE AND OPERATIONS
The City of Tumwater, originally called New Market, was the first American settlement on the Puget
Sound, dating to 1845. The City is well known for a brewery that was established in 1896 and used
groundwater for production. The brewery is no longer in operation. The Palermo Wellfield and Palermo
neighborhood in the Deschutes River Valley were part of a strawberry farm once owned by the Palermo
family. The City began groundwater extraction at the present wellfield in the 1930s and the neighborhood
was developed in the 1950s.
West of the valley is a steep bluff and upland area. This area started to become urbanized in the 1950s
once Interstate 5 was constructed in the area. The Southgate Shopping Center (also referenced in site
documents as the Southgate Mall) and other developments along Trosper Road were developed in the
1970s.
2.2.2 CHRONOLOGY OF ENFORCEMENT AND REMEDIAL ACTIVITIES
Discovery of TCE in the water supply at the Palermo Wellfield in 1993 resulted in a series of
investigations and remedial actions (RA). Multiple potential sources of TCE and PCE were identified in
the upland areas, including the Southgate Dry Cleaners (source of PCE), the current WSDOT MTL north
of Trosper Road (source of TCE), and a former WSDOT MTL south of Trosper Road. The Site was
placed on the National Priorities List (NPL) in 1997.
In 1998 a soil vapor extraction (SVE) system was installed near the Southgate Dry Cleaners PCE source.
This SVE system was operated from March 1998 until June 2000.
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A wellhead air-stripper treatment system was installed for the Palermo Wellfield. This system was put
into operation in 1999 and operation has continued to present. This treatment system is operated by the
City of Tumwater as part of the City's water supply system.
Remedial Investigation (RI) and Feasibility Study (FS) reports were finalized in 1999, and a Record of
Decision (ROD) was finalized in October of that year. Among other items, the ROD included the
following remedy components:
• The wellhead air-stripper treatment system for the Palermo Wellfield that was already in use at
the time of the ROD;
• The SVE system at Southgate Dry Cleaners that had already begun operation at the time of the
ROD; and
• Construction of a subdrain system at the base of the valley bluff just west of the Palermo
neighborhood to lower the water table in the neighborhood.
Semiannual monitoring of groundwater and remedy performance monitoring has occurred since 2001.
The subsurface shallow-groundwater drainage system was constructed along the western edge of the
Palermo neighborhood in 2000-2001. Operation of the system began in 2002.
Two Five-Year-Review (FYR) reports have been completed for USEPA: the first in 2003 and the second
in 2008. The Second FYR listed several recommendations and follow-up actions. Among the
recommendations and follow-up actions that are relevant to this optimization review are the following:
• Prepare and record a deed restriction at Southgate Dry Cleaners or sample SVE treated soil to
determine whether actual soil concentrations require an Institutional Control (1C).
• Conduct a capture zone analysis to assess whether or not the TCE plume is being fully captured
by the operation of the Palermo Wellfield. Analysis shall assess the vertical distribution of
contaminants within the aquifer.
• Evaluate the groundwater monitoring system to assess if existing wells are adequate for
monitoring plume migration and remediation and to determine if additional monitoring points are
required in the downgradient portion of the Site.
• Re-evaluate the CSM and Remedial Action Objectives (RAO) since natural attenuation is not a
significant process for reducing TCE and PCE concentrations in groundwater.
• Continue indoor air monitoring to ensure concentrations of TCE and PCE remain below
1.46 micrograms per cubic meter ((ig/m3) and 4.38 (ig/m3, respectively.
• Re-evaluate the remediation goal (RG) for the groundwater-to-indoor air pathway.
In 2005, the U.S. government initiated a cost-recovery case against two Potentially Responsible Parties
(PRP): WSDOT and Southgate Development Corp. In 2007, a settlement was finalized with Southgate
and the court issued a judgment identifying WSDOT as liable for past and future response actions related
to TCE contamination at this Site.
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2.3 POTENTIAL HUMAN AND ECOLOGICAL RECEPTORS
The primary receptors of potential concern are:
• Users of City water; and
• Occupants of buildings that lie within the aerial footprint of the TCE and PCE plume, especially
residents of the Palermo neighborhood.
The air-stripper treatment of Palermo Wellfield water has been effective in eliminating potential risks to
City water users from TCE or PCE contamination because, based on periodic test data, treated water
concentrations are less than MCLs.
Elimination of potential risk to building occupants is less definitive due to data sparseness, but all indoor
air data collected between 2004 and 2008 in the Palermo neighborhood indicated that concentrations in
air met the indoor air RGs established in the 1999 ROD. No indoor air data have been collected since
2008, and there has been no evaluation of VI in the upland areas.
Other potential receptors may include:
• Private well users within the plume; and
• Humans and ecological receptors that come into contact with contaminated surface water either at
the base of the Palermo Bluff in seeps within the valley, or in drainage ditches.
Presently, there are no known or suspected private-well users in the plume area. City water service is
available throughout the area.
Human exposure to seep water was evaluated quantitatively in the RI and risks were found to be
negligible. A screening-level ecological risk assessment presented in the RI concluded that there were no
significant ecological risks associated with concentrations of PCE and TCE in seeps and ditches near the
Palermo neighborhood. This conclusion was reached because: (1) the measured surface water
concentrations were below ecological toxicity benchmarks; and (2) aquatic receptors are not expected to
be found near the points of groundwater discharge.
If contamination migrates past the Palermo Wellfield, it would likely eventually discharge to the
Deschutes River, which is approximately 1,200 ft to the east of the Palermo area and is a major drainage
feature for the area. The Deschutes River discharges to Capital Lake a little over 1 mile to the north of the
Palermo area, and Capital Lake discharges to Puget Sound.
2.4 EXISTING DATA AND INFORMATION
The information provided in this section is intended to represent data already available from existing site
documents. Interpretation included in this section is generally interpretation from the document from
which the information is obtained. The optimization team's interpretation of this data is discussed in
Sections 4.0 and 5.0 of this report. A cross-section summarizing select soil and groundwater results for
TCE and PCE is presented in Figures 4-8 and 4-9 of the RI (Attachment A: Exhibit A-2a/b).
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2.4.1 SOURCES OF CONTAMINATION
The RI and FS reports identified areas of soil contamination in three primary locations: Southgate Dry
Cleaners in the Southgate Shopping Center; Brewery City Pizza located across Capitol Boulevard to the
east of Southgate Shopping Center; and the Chevron service station located northeast of the intersection
of Trosper Road and Second Avenue (Attachment A: Exhibit A-l). It was recognized in the RI that some
of this soil contamination (such as that identified beneath Brewery City Pizza) had probably resulted from
partitioning of contaminants from groundwater or soil vapor. The RI also indicated contaminated soil
presence at the current WSDOT MTL and at the WSDOT Olympic Region Headquarters south of the
Palermo Wellfield.
The RI indicates that the WSDOT MTL was a source of TCE at the site, consistent with the following
information, some of which is taken from an underground storage tank (UST) Closure Report:
• Historical and recent TCE use at the facility had been documented;
• A TCE release had been documented from an UST system designed to contain spent TCE;
• TCE had been detected on the property and downgradient of the property;
• In 1996, the UST was excavated and removed from the WSDOT MTL property;
• At the time of the excavation, groundwater was encountered at a depth of approximately 7.5 ft.
• The UST was full of water at the time of excavation; and
• A soil sample obtained during excavation at approximately 7 ft below ground surface (bgs)
indicated the presence of TCE at a concentration 0.085 milligrams per kilogram (mg/kg); this
sample was taken between the bottom of the UST and a subsurface concrete slab located
approximately 8 ft bgs.
Per the RI, the groundwater surface in the area of the WSDOT MTL is reportedly observed from 7 to 10
ft bgs in this area. Depth to groundwater is shallow in this area due to the proximity of Barnes Lake. The
depth of the UST excavation is not known. It is also unknown if any remedial measures (e.g., soil
excavation and disposal) were taken during removal of the UST. Given the shallow depth to groundwater,
it is feasible that the UST excavation penetrated the water table. As a result, a TCE release from the UST
system could have had direct access to groundwater.
At the time of the RI, FS, and ROD (1999), the Chevron station was considered to be a likely source of
TCE. However, subsequent investigation led USEPA to conclude that the Chevron was likely not a source
of TCE for the Site; accordingly since 2002, Chevron has not been considered to be a PRP at the Site. In
particular, subsurface sampling at the former WSDOT MTL (south of Trosper Road), located upgradient
of the Chevron station, indicated elevated TCE in the soil and groundwater (reported by URS Greiner in
2001). Also, TCE concentrations at monitoring well (MW) MW-UI, upgradient of Chevron and
downgradient of the former WSDOT facility, have consistently exceeded the MCL and have been higher
than concentrations at a well (MW-ES-07) just downgradient of the Chevron station.
An expert report prepared in 2006 on behalf of USEPA Region 10 (Vlassopoulos, 2006) utilized
compound specific isotope analysis (CSIA) to evaluate if the TCE resulted from degradation of PCE
released from the Southgate Dry Cleaners. The report concluded that the presence of TCE at the Site is
from upgradient of the dry cleaner and potentially related to historical operations of the former and/or
current WSDOT MTL. The RI estimated the PCE release from the dry cleaner may have occurred around
1964 and the release of TCE from a location west of the dry cleaner may have occurred around 1970.
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2.4.2 GEOLOGY SETTING AND HYDROGEOLOGY
The following descriptions of the site geology and hydrogeology are obtained from the RI and FS reports.
Geology of the area consists of Deschutes River fluvial deposits cutting into older glacial deposits. The
glacial sediments consist of the Vashon Drift. Glacial deposits are generally flat in the uplands area with
localized relief comprising Tertiary basalt or marine sandstone. Fluvial sediments in the valley are
unconsolidated sands and gravels with minor silty interbeds. Fluvial deposits range in thickness from
approximately 100 ft to greater than 186 ft, and the Palermo Wellfield wells are completed within these
fluvial deposits (R.F. Weston, 1996). Upland deposits, west of the valley, are recessional outwash
deposits from the Vashon Drift. These deposits are reported to be predominantly sand. Vashon till, a
dense, poorly sorted sand with variable amounts of silt and gravel, is found beneath the recessional
outwash in the southwestern portion of the Deschutes River Valley. The till is reported to be absent in the
uplands area west of the Palermo Wellfield. Bedrock in the study area is described as Tertiary sediments
and basalt. Basalt has been identified in a boring at the Olympia Brewery at a depth of approximately 300
ft bgs and at depths greater than 350 ft bgs at other locations within the Deschutes River Valley.
Two aquifer systems are reported in the study area. The uppermost aquifer system is the Deschutes River
Alluvium and the Vashon Drift. This system is considered to be unconfmed (Vashon Drift in the uplands)
to semi-confined (Deschutes River Alluvium in the valley). The Palermo Wellfield wells are completed
within the Deschutes River Alluvium at depths ranging from 70 to 110 ft bgs. Static water levels within
the Palermo Wellfield wells are generally less than 10 ft bgs. The difference in the depth to the screened
water bearing zone and the depth to water in the completed wells suggests semi-confined conditions in the
valley. Groundwater surface elevations in the uplands are comparable to elevations in the valley. This
suggests that the Vashon Drift in the uplands is unconfmed and hydraulically linked to the Deschutes
River Alluvium. Groundwater flow across the study area is approximately due east with a hydraulic
gradient of approximately 0.03 ft per foot with some radial flow from Barnes Lake. The modeling report
in the RI presents estimates of thickness and hydraulic conductivity (K) for the Vashon Drift/Alluvium
hydrogeologic unit. Based on this information, the combined transmissivity of this unit is approximately
5,800 ft squared per day.
The lower aquifer is identified as the Penultimate Drift, located beneath the interglacial, fine-grained
deposits of the Kitsap Formation. The Kitsap Formation is reportedly a confining layer to the Penultimate
Drift. Static water levels for wells completed within the Penultimate Drift have been reported ranging
from 100 ft bgs to hydraulic heads above the ground surface. All of the site wells are completed in the
uppermost aquifer system.
Depth to water in the upland site wells appears to be approximately 35 to 55 ft bgs. Depth to water in the
valley site wells appears to be approximately 4 to 8 ft bgs with scattered artesian conditions observed near
the base of the bluff.
2.4.3 SOIL CONTAMINATION
Soil sampling with direct-push and monitoring well installation was conducted at several potential source
areas during the RI. The analytical results for these samples as summarized by the RI are presented
below. With the exception of the SVE remedy conducted at the Southgate Dry Cleaners (described later),
the sampling described below is the only soil sampling documented for potential source areas.
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Southgate Shopping Center Area
PCE was detected in 111 of the 176 soil samples analyzed in the Southgate Shopping Center area, at
concentrations ranging from 0.001 to 258 mg/kg. The highest PCE concentration in the Southgate
Shopping Center area and in the entire Site was detected in the soil sample collected from beneath a dry
well located in the floor of the Southgate Dry Cleaners (HA01) at a depth of approximately 4 ft bgs. PCE
was identified in soil in the Southgate Dry Cleaners area from depths of 2.5 to 45 ft bgs with an average
concentration of approximately 4.9 mg/kg. The highest concentrations in soil were at depths of 17 ft bgs
or less. The groundwater surface is approximately 35 to 40 ft bgs in this area.
TCE was detected in 12 of the 160 soil samples analyzed in the Southgate Shopping Center area, at
concentrations ranging from 0.0016 to 1.48 mg/kg at depths ranging from 5 to 40 ft bgs. The highest
concentrations were from 12 to 27 ft bgs. TCE was detected in groundwater at depths very close to the
groundwater surface at several sampling locations in the Southgate area.
An investigation was conducted at the Brewery City Pizza property east of the Southgate Dry Cleaners
(E&E, 1997) in the Capitol 5000 Building area. TCE and PCE were found in groundwater. No
unsaturated-zone source of TCE or PCE was indicated by the soil sampling at Brewery City Pizza,
suggesting that the groundwater contamination originated from an upgradient source.
Current WSDOT MTL
Samples were collected immediately downgradient (east) of the property. PCE was detected in 6 of the 54
soil samples collected from the current WSDOT MTL at concentrations ranging from 0.00011 to 0.0042
mg/kg. PCE detections in soil occurred at depths of 5 to 15 ft bgs. TCE was detected in 4 of 54 soil
samples collected from the current WSDOT MTL at concentrations ranging from 0.00135 to 0.012 mg/kg
(average 0.00801 mg/kg). TCE detections in soil occurred at depths of 5 to!5 ft bgs. A soil sample was
collected from the base of an excavation during the 1996 removal of the UST that contained spent TCE.
According to the RI, a TCE concentration of "85 ppb" was reported for this sample in the facility audit.
The depth of the sample was not reported. A fluid sample from this UST was collected prior to removal.
This fluid sample contained TCE at a concentration of 15,700 micrograms per liter ((ig/L).
Chevron and Former WSDOT MTL
At the time of the RI, FS, and ROD (1999), the Chevron station was considered to be a likely source of
TCE based on TCE detections in soil and groundwater at the property. However, subsequent investigation
led USEPA to conclude that the Chevron was likely not a source of TCE for the site; accordingly since
2002, Chevron has not been considered to be a PRP at the Site. In particular, subsurface sampling at the
former WSDOT MTL (south of Trosper Road), located upgradient of the Chevron station, indicated
elevated TCE in the soil and groundwater (reported by URS Greiner in 2001). Also, TCE concentrations
at monitoring well MW-UI, upgradient of Chevron and downgradient of the former WSDOT facility,
have consistently exceeded the MCL and have been higher than concentrations at a well (MW-ES-07) just
downgradient of the Chevron station.
WSDOT Olympic Region Headquarters
The RI notes that TCE was detected in soil and groundwater samples at three locations near the WSDOT
Olympic Region Headquarters south of the Palermo Wellfield. TCE was detected in soil samples from the
ground surface to the groundwater surface indicating that a surface release or releases likely occurred in
the immediate area of one or more of these locations. PCE was detected in only 1 of the 21 soil samples
collected from this facility at a concentration below 0.001 mg/kg. TCE was detected in 16 of the 21 soil
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samples collected from this facility at concentrations ranging from 0.00068 to 0.11199 mg/kg at depths
ranging from 5 to 45 ft bgs. The highest concentrations were present from depths of 20 to 45 ft bgs. The
groundwater surface occurs at approximately 45 ft bgs.
The plumes depicted in site groundwater monitoring reports do not depict groundwater contamination
near this facility.
2.4.4 SOIL VAPOR OR INDOOR AIR CONTAMINATION
Ambient air samples have been collected from crawlspaces and home interiors across the Palermo
neighborhood beginning in 2001. A figure from the Second FYR Report showing the residential
neighborhood and the location of the subdrain system (constructed as a French drain) and indoor air
sample locations is provided as Exhibit A-3 (see Attachment A). A chart presenting the indoor air and
crawlspace sample analytical results is provided as Attachment B. No indoor air or crawlspace samples
have been collected since 2008. There are 47 homes in the residential neighborhood. A total of 24
different homes have been tested. Home testing frequency is summarized below:
No samples 23 homes
One sample 2 homes
Two samples 10 homes
Three samples 2 homes
Four samples 7 homes
Five samples 3 homes
Sampling events typically included both home interior and crawlspace samples, but on occasion
crawlspace samples are not collected. Sample events since 2004 have met the indoor air RGs, but only
eight homes have been sampled since 2004. Those eight homes are located in the downgradient portion of
the highest TCE concentrations in groundwater (from roughly the 25 to 100 (ig/L TCE contour), but did
not include homes located west of Rainier Avenue, including the southern two homes (5101 and 5103 SE
Rainier Avenue; air-sampling locations #5 and #6) that are located within or near the 100 (ig/L contour
for TCE in groundwater and do not meet the ROD-specified RG for groundwater depth.
Since 2001, one indoor air sample has exceeded the 4.38 (ig/m3 RG for PCE in indoor air. The sample
was taken at 206 SE N Street (air-sampling station #20) in December 2004 and the PCE concentration
was 18 (ig/m3; no later samples were collected at this location. The corresponding crawlspace sample
result was two orders of magnitude lower for PCE (0.17 (ig/m3). Since 2001, six indoor air samples have
exceeded the 1.46 (ig/m3 RG for TCE. These TCE exceedances occurred at 220 SE O Street (air-sampling
station #7: 1.8 (ig/m3), 5004 SE Rainier Avenue (air-sampling station #8: up to 3.1 (ig/m3), 206 SE O
Street (air-sampling station #9: up to 3.1 (ig/m3), and 5002 SE Rainier Avenue (air-sampling station #13:
2.6 (ig/m3). For each TCE exceedance in indoor air, at least one sample was collected afterward that met
the indoor air RG for TCE. One crawlspace sample exceeded the indoor air goal for PCE and four
crawlspace samples exceeded the indoor air goal for TCE.
The ability to acquire a robust data set of indoor air and crawlspace sample results from across the
neighborhood is dependent on gaining property owner consent and occupant cooperation. As a result, the
current data set lacks consistency.
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2.4.5 GROUNDWATER CONTAMINATION
Groundwater sampling was conducted at monitoring wells and direct-push drilling locations concurrently
with the soil sampling described in Section 2.4.3. Groundwater analytical results from this sampling are
discussed for the same properties presented in Section 2.4.3.
Southgate Shopping Center
During the RI, PCE detections extended from the groundwater surface at approximately 32 ft bgs to over
120 ft bgs. The highest PCE concentrations in groundwater were located from 35 to 75 ft bgs. PCE was
detected in 82 of the 108 groundwater samples analyzed in the Southgate Shopping Center area at
concentrations as high as 949 (ig/L. TCE was detected in 50 of the 108 groundwater samples analyzed in
the Southgate Shopping Center area. The highest TCE concentration (169 (ig/L) in groundwater was
detected in a sample collected from well MW-ES-01 at a depth of approximately 95 ft bgs. This well is
located in the extreme northern portion of the Southgate Shopping Center property directly downgradient
of the current WSDOT MTL, suggesting that the current WSDOT MTL was the principal source for the
elevated TCE at this location.
Current WSDOT MTL
During the RI, PCE was detected in 9 of the 107 groundwater samples collected from the current WSDOT
MTL area at concentrations as high as 34.55 (ig/L and at depths ranging from 25 to 75 ft bgs. The highest
PCE detection (34.55 (ig/L) was detected in the groundwater sample collected downgradient of the
current WSDOT MTL at a depth of 25 ft bgs. The remaining groundwater samples displayed PCE
concentrations at or below 2 (ig/L. TCE was detected in 33 of 108 groundwater samples collected from
the current WSDOT MTL area at concentrations as high as 72.8 (ig/L and at depths ranging from 13 to 75
ft bgs. The highest TCE detection in groundwater occurred at a depth of approximately 45 ft bgs and
approximately 240 ft east (downgradient) of the facility. The shallowest TCE detection in groundwater
(13 ft bgs) occurred immediately adjacent to the former UST position.
Chevron
During the RI, PCE detections in groundwater in the area of the Chevron station were no higher than 2.6
(ig/L. TCE was detected in 46 of the 74 groundwater samples collected from the Chevron service station
area at concentrations as high as 50.8 (ig/L. TCE detections occurred at depths ranging from 20 to 75 ft
bgs. The highest TCE detections were generally located at depths between 20 and 35 ft bgs (upper portion
of the saturated zone).
WSDOT Olympic Region Headquarters
During the RI, PCE was not detected in the 22 groundwater samples collected from this area. TCE was
detected in 9 of the 22 groundwater samples collected from this area at concentrations as high as 8.6
(ig/L. TCE detections occurred at depths ranging from 50 ft bgs (near the groundwater surface) to 65 ft
bgs. The highest TCE detections are generally located at 50 ft bgs (upper portion of the saturated zone).
Site-Wide Groundwater Sampling
Groundwater quality data has been collected by USEPA contractors on a semiannual basis. The LTM
program includes 21 groundwater sampling locations: 15 monitoring wells, three shallow piezometers in
the Palermo neighborhood, and three production wells in the Palermo Wellfield. Water level
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measurements are also collected at the monitoring wells and piezometers. Figures from the most recent
Annual Groundwater Monitoring Report are included in Attachment A as Exhibits A-4 and A-5 to show
measured PCE and TCE concentrations at the LTM sampling locations in October 2010. PCE and TCE
concentrations are also measured in the groundwater subdrain system at four cleanout locations as part of
performance monitoring for that system. Plots illustrating PCE and TCE trends in the site monitoring
wells are provided in Attachment C. Plots illustrating PCE and TCE trends in the subdrain system are
provided in Attachment D.
In October 2010, only two LTM monitoring wells had measured PCE concentrations above the 5 (ig/L
MCL. These two wells (MW-ES-06 and MW-ES-04) are in the upland area downgradient of the
Southgate Dry Cleaners. The maximum measured PCE concentration was 34 (ig/L (MW-ES-04). PCE
was not detected in the monitoring wells, piezometers, or production wells in the valley; however PCE
was measured at concentrations between 5.3 (ig/L and 13 (ig/L in the subdrain system along the western
edge of the Palermo neighborhood.
Based on October 2010 data, TCE concentrations exceed the 5 (ig/L MCL at nine of the 15 monitoring
wells, all three piezometers in the Palermo neighborhood, and at TW-2 in the Palermo Wellfield. Also,
the subdrain system measurements all had concentrations of TCE above the MCL. The highest measured
TCE concentration in October 2010 was 130 (ig/L at a monitoring well (MW-ES-09) in the southwestern
portion of the Palermo neighborhood.
2.4.6 SURFACE WATER CONTAMINATION
A total of 14 surface water seep samples were collected for volatile organic compound (VOC) analysis
along the base of the bluff west and south of the homes along the west side of Rainier Avenue during the
RI. TCE and/or PCE were detected in nine of the 14 samples. Maximum TCE and PCE concentrations in
the seep water were 60 (ig/L and 45.4 (ig/L, respectively, both from sample SW-107 which was collected
at a point west-northwest of the house at 5003 SE Rainier Avenue (air-sampling station #4), between
current piezometer locations PZ-708 and PZ-709, and west of cleanout #4 (CO4) of the subdrain. A
surface water sample from a crawlspace beneath a home along the west side of Rainier Avenue, contained
115 (ig/L TCE and 102 (ig/L PCE, the highest concentrations found during the RI surface water sample
round.
A human health risk assessment (HHRA) was performed as part of the RI. Exposure to seep water
containing TCE and PCE was included in the risk assessment. A quantitative evaluation was performed
for pathways consisting of incidental ingestion of and dermal contact with water by elementary school-
age children playing in the ditches. Inhalation of air contaminants from the ditches was excluded from
quantitative analysis because exposure via the ambient air pathway was assumed to be negligible. The
total risk for both exposure pathways combined was calculated to be 1 x 10"7 with a hazard quotient of
0.004. The dermal contact exposure pathway was found to contribute the majority of the risk, above that
posed by incidental ingestion. Seeps continue to occur west of homes along Rainier Avenue and south of
homes along O Street. Current seep water is expected to contain PCE and TCE above MCL values.
Surface water sampling since the RI has historically been limited to VOCs associated with the aeration
pond that collects shallow groundwater from the subdrain on the west and north sides of the Palermo
neighborhood. The intent of this sampling is to ensure that surface water standards for PCE and TCE are
being met at the point of discharge from the aeration pond to the nearby Deschutes River. The results
indicate no exceedances of ROD goals for this sampling.
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During the Site visit, the project team encountered what appeared to be a surface water expression of
shallow groundwater emanating from the Palermo Bluff. Flowing surface water was identified in a trench
beginning at the base of the bluff in the southwest corner of the Palermo neighborhood and extending east
along the southern edge of the neighborhood down to the Palermo Wellfield. In addition, while walking
along the base of the bluff to the west side of the Palermo neighborhood, the team noted several
interesting surface features including a 6" polyvinyl chloride (PVC) pipe extending down from the
parking areas on top of the bluff to within a few feet of the base of the bluff and another surface water
feature (low lying swamp area) just east of the PVC pipe. These features are illustrated in Attachment E.
The seeps and the drainage water from the PVC pipe have not been sampled. These features are shown in
the attached Photolog (Attachment F).
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3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES
The information provided in this section is intended to represent information already available from
existing Site documents. Interpretation included in this section is generally interpretation from the
document from which the information is obtained. The optimization team's interpretation of this
information and evaluation of remedy components are discussed in Sections 4.0 and 5.0 of this report.
3.1 REMEDY AND REMEDY COMPONENTS
The Site remedy has consisted of several remedy components specified in the 1999 ROD and summarized
in the Second FYR. Each of these components is described in the following subsections.
3.1.1 WELLHEAD TREATMENT AIR STRIPPERS
Two air-stripper towers with associated blowers, an underground clearwell, and pumps and piping were
constructed as part of a removal action in advance of the ROD and were incorporated into the selected
remedy. The treatment system is designed to remove TCE contamination in the water from wells TW-2,
TW-4, and TW-5. It was transferred to the City for operation in April 1999. In addition to removing TCE
from the City's water supply, the air-stripper system also removes natural carbon dioxide which helps to
increase the pH and reduce levels of certain metals at water taps in the City's distribution system.
3.1.2 SUBDRAIN AND TREATMENT LAGOON
A subdrain system consisting of perforated PVC collection pipe in gravel was installed at the foot of the
bluff to the west of the Palermo neighborhood to lower the water table in the neighborhood (see
Attachment A: Exhibit A-6). The subdrain consists of a 600-foot long trunk drain, eight finger drains
(each approximately 75 ft long) oriented perpendicular to the trunk drain, and several cleanouts. The total
depth of the trench and cleanouts varies between approximately 7 and 8 ft bgs. Water elevation in the
drain ranges from a high of 104 ft above mean sea level (amsl) at the southern end to approximately 102
ft amsl at the northern (discharge) end. Collected water flows by gravity to a set of three aeration lagoons
to the west of the neighborhood with a design water elevation of 97 ft amsl. Water is treated by lagoon
aeration with three 3 horsepower (HP) aerators prior to gravity discharge to the Deschutes River. The
subdrain and aeration lagoons have been operating continuously since installation was completed in
January 2001. Measured subdrain flow rates vary seasonally and annually, but have averaged 135 gallons
per minute (gpm) over the 28 measurement events since 2001 as measured at the subdrain outfall (Station
360). Recent subdrain flow rates have been among the highest recorded, at 204 and 246 gpm in May and
October 2010, respectively. The average 135 gpm flow rate from the subdrain equals 70 million gallons
of shallow groundwater removed per year on average.
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3.1.3 STANDING WATER EVALUATION
The 1999 ROD specified additional evaluation of potential standing water in home crawlspaces and
contingent actions if standing water was present (i.e., lowering the water table or venting the
crawlspaces). This evaluation is ongoing; the potential presence of standing water is evaluated during
semiannual subdrain performance monitoring. If standing water is present, sampling of the standing water
in the crawlspaces and performing a HHRA is specified. If the risk assessment shows unacceptable risks
then the remedy is to either lower the water table or vent the crawlspace, whichever is more cost effective.
3.1.4 SVE
The SVE system was constructed and tested between November 1997 and March 1998 adjacent to the
Southgate Shopping Center building that contains Southgate Dry Cleaners. The system included four
vapor extraction wells in the parking lot and one inside the dry cleaner. Extracted vapors were treated
with granular activated carbon (GAC) units and discharged through a 20-foot tall emission stack. The
SVE system was operated from March 1998 through June 2000. The Second FYR includes the following
information from the preliminary close out report:
"The SVE system began operation on March 24, 1998, and removed approximately 425 pounds
ofPCE before it was decommissioned in June 2000, based on comparing the results of vapor
samples collected from the system at startup to those collected just prior to decommissioning. The
highest concentration ofPCE in soil beneath Southgate Dry Cleaners prior to remediation was
63.2 mg/kg. By applying the ratio of the PCE concentration in vapor samples at startup and just
prior to decommissioning to the concentration in soils prior to remediation, an average PCE
concentration remaining in soil within the area of SVE system influence is estimated at 0.013
mg/kg. This is below the soil remediation goal (RG) of 0.0858 mg/kg. However, the one
confirmation soil sample collected in the same area following decommissioning of the SVE
system indicated a concentration ofO. 232 mg/kg PCE. This indicates the presence of isolated
areas of soil beneath Southgate Dry Cleaners containing PCE concentrations still in excess of the
RG and therefore requires a deed restriction on the property in accordance with the ROD. "
3.1.5 LONG-TERM GROUND WATER MONITORING
As described in Section 2.4.5, the LTM program includes semi-annual sampling of the following 21
groundwater sampling locations for VOCs as illustrated on Exhibit A-l (see Attachment A):
• 15 monitoring wells;
• three shallow piezometers in the Palermo neighborhood; and
• three production wells in the Palermo Wellfield.
Water levels are also collected at the monitoring wells and piezometers semi-annually.
3.1.6 MONITORING OF SUBDRAIN AND LAGOON PERFORMANCE
The performance of the subdrain system is monitored on a semi-annual basis as follows:
• Measure depth-to-water in eight subdrain cleanouts (CO1 through COS, all located west of the
homes along Rainier Avenue) and 12 piezometers (PZ-704, PZ-709, PZ-715, PZ-719 through PZ-
726, PZ-728) to assess depth to groundwater.
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• Measure total depth in the same eight subdrain cleanouts and in three catch basins (CB-1, CB-2,
CB-3) to assess for sedimentation in the drain line and conveyance piping.
• Measure total depth of the treatment lagoon along three cross sections (Al, A2, A3) to assess for
sedimentation or scouring.
• Measure flow rates and collect water samples for chemical analysis from three drain cleanouts
(sample locations 357, 358 and 359 which correspond to drain cleanouts CO1, CO4 and CO6,
respectively); three outfalls to the treatment lagoon (sample locations 360 - subdrain outfall, 350
- storm drain outfall, and 362 - terminus catch basin outfall); and three surface water stations
near the treatment lagoon (356, 361, 364) to assess contaminant removal performance. Sample
station 361 is the treatment lagoon discharge location and sample station 364 is the discharge
location to the Deschutes River located approximately 2,000 ft north of the treatment lagoon.
Sample station 356 is located upstream of the treatment lagoon.
3.1.7 PUBLIC NOTICE OF CONTAMINATED GROUND WATER
USEPA published a fact sheet in February 2001, which was sent to local well drillers and property
owners. The fact sheet included an alert concerning installation of new wells in the area of contaminated
groundwater. A figure was included to show the area of contamination. In addition to this public notice,
the City requires that all properties within the city limits be connected to the City water supply. This
requirement is a disincentive to the drilling of new private wells.
3.2 RAOs AND STANDARDS
The following RAOs and associated performance standards are identified in the ROD:
1. Clean up the groundwater aquifer. The relevant standards are MCLs (5 (ig/L for both PCE and
TCE).
2. Prevent ingestion of, or exposure to, groundwater containing carcinogens in excess of applicable
or relevant and appropriate requirements (ARAR) and total excess cancer risk no greater than
10"6. The relevant standards are MCLs (5 (ig/L for PCE and TCE).
3. Prevent inhalation of chemicals of concern (COC) via vapors from surface water in residential
crawlspaces at concentrations that result in a total excess cancer risk of greater than 10"6. The
target indoor air values for PCE and TCE are 4.38 (ig/m3 and 1.46 (ig/m3, respectively.
4. Prevent discharge of groundwater containing PCE and TCE to the Deschutes River at
concentrations in excess of ARARs or resulting in an ecological hazard index (HI) greater than 1.
Discharge standards are 0.8 (ig/L for PCE and 2.7 (ig/L for TCE.
5. Reduce the potential for PCE in soils under the Southgate Dry Cleaners to reach the groundwater.
To achieve the objective related to inhalation of vapors, a performance goal for the subdrain is to lower
the water table to a depth 3 ft below the bottom of the crawlspaces. The 3-foot protective depth to
groundwater is referenced in the Second FYR Report and includes a margin of error in the event
crawlspace floors are 1.5 ft in depth as opposed to at grade. The depth to groundwater was based on
Johnson-Ettinger modeling showing a reduction of potential inhalation risks to acceptable levels.
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3.3 PERFORMANCE MONITORING PROGRAMS
The performance monitoring programs are described in Section 3.1.5 and 3.1.6 as components of the
remedy.
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4.0 CONCEPTUAL SITE MODEL
This section discusses the optimization team's interpretation of existing characterization and remedy
operation data and Site visit observations to explain how historic events and site characteristics have led
to current conditions. This CSM may differ from that described in other site documents. CSM elements
discussed are based on data obtained from USEPA Region 10 and discussed in the preceding sections of
this report. This section is intended to include interpretation of the CSM only. It is not intended to provide
findings related to remedy performance or recommendations for improvement. The findings and
recommendations are provided in Sections 5.0 and 6.0, respectively.
4.1 CSM OVERVIEW
Figure 1 is a cross-section illustration of the CSM as interpreted by the optimization team.
VOC contamination released at the surface and/or in the shallow subsurface from the Southgate Dry
Cleaners and both the current and former WSDOT MTL facilities has impacted groundwater at the site.
The soils are relatively permeable (described as sands) and low in organic carbon. In addition, the releases
in some cases may have occurred approximately 25 years before the RI sampling occurred. These factors
contributed to relatively low soil concentrations observed during the RI and may have resulted in
relatively weak continuing sources of dissolved groundwater contamination measured in 2010 at these
previously identified sources.
In the case of the current WSDOT MTL, groundwater is sufficiently shallow in that area that groundwater
may have been impacted by the historic release from the UST without significantly impacting unsaturated
soils. In the case of the Southgate Dry Cleaners, substantial PCE mass was removed with an SVE remedy.
The relatively high groundwater flow rates and low organic carbon have contributed to contaminant
flushing over the period of three to four decades from the time of the original releases until present. As a
result, the majority of contamination associated with the original releases appears to have migrated away
from the source areas and is now present in the vicinity of the Palermo neighborhood. Diffusion limited
transport into and out of relatively impermeable zones in the aquifer may somewhat retard the flushing.
Relatively low levels of contamination in soil that are spatially limited result in low-level fluctuating
concentrations in the former source areas. The SVE system has been successful at substantially reducing
the mass of contamination in soil, likely resulting in reductions in groundwater concentrations at the dry
cleaner. PCE groundwater concentrations downgradient of the Southgate dry cleaner, however, remain
above standards and are declining at a very slow rate, suggesting that some source material may continue
to cause low level groundwater contamination or that flushing of the remaining levels of contamination is
diffusion limited. This may also be the case at some of the other source areas, and existing sampling
locations are insufficient to tie portions of the plume back to the potential sources.
The known extent of VOC groundwater plume is approximately 3,000 ft long and includes the Palermo
Wellfield. The fate of contaminated groundwater includes surface expression as seeps in the vicinity of
the Palermo neighborhood, capture by the subdrain system, extraction by the Palermo Wellfield, or
potentially migration beyond the Palermo neighborhood and Palermo Wellfield. Contaminant migration
pathways begin at the water table near the source areas and gradually migrate deeper as a result of
regional pumping and recharge. Due the relatively eastern location of the main PCE source area
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(Southgate Dry Cleaners), it is likely that the PCE has remained sufficiently shallow to be captured by the
subdrain system as reflected by the PCE concentrations in the subdrain and the absence of PCE detections
in groundwater downgradient of the subdrain. PCE concentrations have been decreasing in the subdrain
because the PCE source was mostly removed and residual PCE is being flushed from the aquifer. TCE
contamination, which started migrating from sources further west, has had the opportunity to migrate
slightly deeper and is more dispersed. The TCE plume core likely migrates under the subdrain. The
removal of water from the subdrain and the surface expression of seeps due to the abrupt change in
regional topography result in an upward gradient in the valley such that some of the deeper TCE migrates
closer to the surface in the Palermo neighborhood and some is extracted by the Palermo Wellfield. TCE
concentrations in the upland (area of original sources) are declining in the absence of strong continuing
sources, but concentrations near the subdrain and the Palermo neighborhood may have recently peaked
and are only now beginning to slowly decline. If finer sediments are present at the interface of the Vashon
Drift and alluvium, diffusion limited transport into and out of these sediments could contribute to slowing
concentration reductions. Shallow groundwater contaminated with TCE and PCE and/or shallow
groundwater discharging to the surface represent potential VI exposures for residents in the Palermo
neighborhood north of the Palermo Wellfield operated by the city of Tumwater, Washington.
4.2 CSM DETAILS AND EXPLANATION
This section provides CSM details pertaining to key questions for the optimization evaluation. Key
considerations include:
• TCE and PCE source areas, groundwater plume morphology
• Shallow groundwater and potential VI in the Palermo neighborhood
• Historical information for CSM elements
4.2.1 TCE AND PCE SOURCE AREAS, GROUNDWATER PLUME MORPHOLOGY
The CSM as presented by the optimization team suggests that the majority of contaminant mass may have
already migrated from the source areas due to high natural groundwater flushing rates and that relatively
weak residual sources are contributing a low flux of contamination to groundwater. This CSM is
generally supported by decreasing TCE concentration trends in many upland monitoring wells (e.g., MW-
109, MW-111, MW-ES-03, and MW-ES-05) and low-level fluctuating concentrations near the former
WSDOT MTL (e.g., MW-UI and MW-ES-07). The declines to date are the result of decades of
groundwater flushing in the absence of a strong continuing source. Using a K of approximately 10 ft per
day (consistent with RI modeling assumptions), a hydraulic gradient of 0.03 ft per foot (measured), and
an effective porosity of approximately 0.25 (reasonable assumption), the groundwater seepage velocity is
over 400 ft per year, allowing for approximately 5 pore volumes of flushing of the 3,000-foot long plume
over a 30 to 40 year period (e.g., from approximately 1970 to approximately 2010).
With regard to PCE and TCE in the area of the Palermo neighborhood, groundwater elevations for paired
wells MW-ES-09 and MW-ES-10 indicate an upward component of groundwater flow in this area. In
addition, a review of TCE results for shallow well MW-ES-09 (screen interval 20-30 ft bgs, 130 (ig/L)
and a nearby shallow piezometer PZ-724 (87 (ig/L) are indicative of TCE contamination at shallow
depths downgradient of the subdrain. Deeper wells in this same vicinity such as MW-ES-02 (screen
interval 95-105 ft bgs) and MW-ES-10 (screened interval 82-92 ft bgs) have historically detected
approximately one half or less (47 (ig/L and 46 (ig/L respectively) of the highest concentrations found at
well MW-ES-09 and nearby piezometer PZ-724. The presence of TCE concentrations of approximately
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30 (ig/L in the subdrain, higher concentrations in the shallow zone (130 (ig/L at MW-ES-09), and the
upward gradient in the Palermo neighborhood suggest the likelihood that the TCE plume core (and lower
concentrations at deeper intervals) migrate beneath subdrain. By contrast, PCE contamination appears to
be sufficiently shallow that it is presumably discharged in the surface seeps at the base of the bluffs and
captured by the subdrain.
TCE concentrations at MW-ES-09 are currently the highest observed TCE concentrations at the Site and
concentrations are declining slowly, indicating it will take many decades to reach MCLs in this area with
the current remedial approach, even if upland sources have been removed. In addition, the higher
concentrations at shallower depths (compared to wellfield pumping at deeper depths) and the position of
the Palermo Wellfield south of the plume core increases likelihood that the wellfield may not provide full
capture (plume capture is further discussed in Section 5.2.2).
The extent of the TCE and PCE plumes are also not well-defined along the southern plume boundaries.
Plume contours presented in Attachment A: Exhibits A-4 and A-5 are not bound by monitoring wells;
however several existing wells to potentially address this data gap were identified during the site visit by
visual confirmation and maps provided by City employees from the Palermo Wellfield. Some of the wells
appear to be owned by the City of Tumwater and may be helpful in delineating the southern plume
boundary including: CT-MW-2 (may also be known as TUM MW-96-16) and two CT-MW wells located
on Linda and Ruby Streets.
4.2.2 SHALLOW GROUNDWATER AND VI
Due to an abrupt drop in topography between the upland and the valley, the groundwater at the base of the
bluff and east to the Palermo neighborhood discharges in surface seeps. TCE and PCE are present in the
shallow groundwater at the base of the bluff. The subdrain was installed in an attempt to mitigate seeps
and reduce the water table elevation. Shallow groundwater TCE concentrations in the Palermo
neighborhood exceed 100 (ig/L (MW-ES-09). VI associated with shallow groundwater remains a concern
in the Palermo neighborhood. VI sampling results to date are presented in Section 2.4.4. Interpretation of
those results is discussed further in Section 5.3.2 of this report.
4.2.3 HISTORICAL INFORMATION AND CSM ELEMENTS
There are a number of site features associated with the CSM, where additional information may lead to
improved remedy performance and monitoring. There may be relatively small but important preferential
pathways or specific localized flow regimes that can impact remedy performance near the Palermo
neighborhood.
Historical site topographic and aerial photos included as part of the EDR report provided in Attachment G
were also reviewed for indication of historical land use and changes in surface features that may impact
surface or shallow groundwater flow. Both the 1957 aerial photo and the 1959 topographic map show
distinct surface road features extending down from the bluff both north of the Palermo neighborhood (M
Street) and south of the neighborhood (area just North of Linda Street extending down to the Palermo
Wellfield). These surface features topographically bound the current plume depictions to the north and
south. In addition the United States Geological Survey 7.5 minute topographical maps provided in the
EDR report (Attachment G) provide decent site coverage from 1949, 1959, 1968, 1973, and 1981;
however, the contour intervals are such that there is no obvious evidence of a drainage feature noted along
the bluff. The eastern most (highest) topographic lines in these maps do have a small inflection along the
bluff southwest of the Capitol 5000 building, which is suggestive of a drainage feature. This shape
however is not repeated in the two western (lower) topographic lines indicating that it is not a prominent
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feature along the entire bluff. It should be noted that the PVC pipe identified at the base of the bluff
during the optimization site visit on August 25, 2011, is adjacent to this topographic feature (Attachment
E).
In addition to site physical features, historical land use in the area is also an important CSM component.
A review of historical aerial photos and topographic maps provide some detail to potential land use in the
site area. There is minimal development on the top of the bluff identified in aerial photos prior to the 1957
photo. A housing area at the top of the bluff is observed in the 1959 topographic map and continues to be
observed until the 1973 topographic map where minimal housing structures are again observed. The 1981
topographic map, however, calls out a trailer park in this same area. A review of the aerial photographs
from this same time frame (1969 and 1973 photos provide best evidence) match the topographic maps
well and show a lot of structures and elongated buildings indicative of trailer homes along the bluff.
Topographic maps obtained do not extend beyond 1981, however by the 1990 aerial photo all apparent
trailer home structures are gone and commercial buildings appear including the Capitol 5000 building and
the Brewery City Pizza building. While historical residential and commercial land use along the bluff
does not indicate operations of significance, the continued redevelopment of this area likely involved
excavation, grading, and other shallow surface operations that can impact shallow groundwater and
surface water migration in this area.
Similarly, historical use of the former and current WSDOT MTL facilities along with their relationship to
shallow stratigraphy both at these facilities and at the nearby bluff west of the Palermo neighborhood are
key hydrogeologic CSM features pertaining to the question of preferential migration pathways and
remedy performance. A review of aerial photos and topographic maps indicates that the current WSDOT
MTL began operations between 1969 and 1973 while the 1957 aerial suggests some operations of the
former WSDOT MTL.
4.3 DATA GAPS
There are several data gaps in the existing CSM. These are discussed in Section 5.0.
4.4 IMPLICATIONS FOR REMEDIAL STRATEGY
The implications of the CSM and above data gaps are discussed in Sections 5.0 and 6.0.
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5.0 FINDINGS
The observations provided below are the interpretations of the optimization team. They are not intended
to imply a deficiency in the work of the system designers, system operators, or site managers but are
offered as constructive suggestions in the best interest of the USEPA and the public. These observations
have the benefit of being formulated based upon operational data unavailable to the original designers.
Furthermore, it is likely that site conditions and general knowledge of groundwater remediation have
changed over time.
5.1 SOURCES
5.1.1 CONNECTION OF PLUMES TO SOURCES
The plume depictions in LTM reports show the high-concentration portions of the TCE and PCE plumes
downgradient of the source areas. While it may be that the areas of relatively high concentration have
migrated downgradient in the groundwater and the source areas are now relatively clean (as discussed in
Section 4.0), additional data are needed to confirm or disprove this hypothesis.
There are no LTM concentration data near the current WSDOT MTL or immediately downgradient of
Southgate Dry Cleaners, so separation of the TCE and PCE plumes from those sources cannot be
confirmed.
The delineation of the TCE plume lacks sufficient resolution to identify potential pathways from sources
to plume hot-spot areas.
5.1.2 SVE EFFECTIVENESS
The SVE system was shut down and dismantled once PCE removal rates declined to a very low rate
compared to early removal rates. One confirmation soil sample was collected, but this sample did not
meet the ROD goal. Remaining soil contamination may be sufficient to cause VI concerns or to act as a
continuing source of dissolved groundwater contamination.
5.2 GROUNDWATER
5.2.1 PLUME DELINEATION
The definition of the groundwater plume, as presented in the LTM reports is incomplete. In particular, the
northern, northeastern, and southern extents of the TCE plume (as defined by the concentration contour
corresponding to the MCL) are not confirmed due to lack of available concentration data. To the north,
MW-ES-01 had elevated TCE concentrations (169 (ig/L) during the RI. To the northeast, the plume may
extend beyond the Palermo neighborhood.
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The depicted PCE plume is separated from the Southgate Dry Cleaners source area even though there are
no data near that source to confirm this condition. Also, the depicted PCE plume does not extend across
the valley bluff even though PCE is routinely detected above the MCL in the subdrain system that
intercepts shallow groundwater.
5.2.2 PLUME CAPTURE
The ROD assumes, based mainly on numerical groundwater modeling performed during the RI, that
groundwater extraction at the Palermo Wellfield does capture, and will continue to capture, the entire
TCE plume. However, plume capture cannot be confirmed with the available head and concentration data
set. Furthermore, the wellfield operator (City of Tumwater) is under no obligation to maintain extraction
rates at levels that will ensure continued plume capture.
Plume capture can be evaluated per USEPA guidelines documented in A Systematic Approach for
Evaluation of Capture Zones at Pump and Treat Systems (EPA 600/R-08/003). Under these guidelines,
capture effectiveness is evaluated using a weight-of-evidence approach that may consider the following
types of analyses:
• Review of potentiometric surface maps generated from water-level measurements;
• Review of measured concentrations in groundwater wells downgradient of extraction wells;
• Calculation of the expected flow needed for capture using available estimates of aquifer
transmissivity, hydraulic gradient, and plume width; and
• Numerical groundwater modeling.
Potentiometric Surface Maps
There are inadequate head data to infer a regional potentiometric surface that would be needed to
establish the capture zone of Palermo Wellfield. In particular, there are no piezometers within the
wellfield and regional head data are not collected/evaluated as part of the LTM program.
Concentration Trends
There have been no detections of PCE or TCE at MW-110, which is east of the Palermo neighborhood.
This fact supports the hypothesis of complete plume capture at the wellfield. Additional confirmation at
points north and south of MW-110 would be helpful. The near-surface (shallow) portion of the plume is
the critical portion to monitor.
Groundwater Flow and Extraction
Simple calculations can be made to estimate the flow that would be needed to fully capture the plume.
Such calculations are described in the USEPA guidance on capture-zone evaluation. While the
calculations assume ideal and non-realistic conditions (e.g., homogeneity, two-dimensional porous-media
flow, no recharge), they are informative for making initial approximations of extraction rates required for
hydraulic containment.
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One of the simplest calculations provides an estimate of minimum flow (0 needed for capture of a plume
of known width (w) given uniform aquifer transmissivity (7) and hydraulic gradient (J): Q = TJw. The
aquifer transmissivity is the product of aquifer K and aquifer thickness: T = Kb.
For purposes of this evaluation, it is assumed that the target capture zone is the TCE plume greater than
5 (ig/L. The width (w) of the target capture zone is approximately 800 ft as measured from the figure in
Attachment A.
Using this same figure, the hydraulic gradient in the valley is estimated to be 0.03 (10 ft head drop over
approximately 330 ft distance) in the valley.
The modeling report in the RI presents estimates of thickness and K for the Vashon Drift/Alluvium
hydrogeologic unit. Based on this information, the combined transmissivity of this unit is approximately
5,800 feet squared (ft2)/day. It is assumed in this analysis that the Kitsap Formation limits groundwater
flow from the deeper Penultimate Drift to the Palermo wells (which are screened in the alluvium).
Based on these estimates of transmissivity, hydraulic gradient, and plume width, the required flow rate to
capture the TCE plume is approximately 140,000 cubic feet (ft3)/day, or 720 gpm. It should be noted that
this flow rate is based on approximations of key parameters (particularly transmissivity) and idealized
assumptions. Using a 1.5 uncertainty factor (assumed), the required flow rate could be between 500 and
1000 gpm.
The average flow rate from the Palermo Wellfield has traditionally been over 800 gpm. However, based
on data received from the City, the average total production from the wellfield in 2010-2011 has been less
than 400 gpm. It appears that production from Palermo has been decreasing for the past decade, with
other groundwater sources (primarily the Bush Middle School Wellfield) making up a larger portion of
the total City water supply. The City is evaluating ways to increase the flow rate from Palermo, including
rehabilitation of TW-5 and possible replacement of TW-2.
Also, the Palermo wells are not directly downgradient of the TCE plume and are deeper than the
shallower plume core (e.g., MW-ES-09), which means that a portion of the wellfield capture zone does
not overlap the plume.
Based on this simplistic analysis, the amount of flow required to capture the TCE plume is similar to
(perhaps greater than) the current production rate of the entire Palermo Wellfield. This line of evidence
does not support a hypothesis of complete capture.
Numerical Groundwater Modeling
Numerical modeling conducted during the RI indicated complete capture of the TCE and PCE plumes by
the Palermo Wellfield. The modeling used reasonable methods and assumptions and a total wellfield
production rate of 840 gpm based on then-current information. The actual capture zone determined from
the model results was several thousand feet wide, extending from Barnes Lake to points south of the
wellfield. The TCE and PCE plumes are entirely within the model-estimated capture zone.
In general, numerical modeling of capture zones will be more accurate than simple calculations of
required extraction to achieve capture (e.g., as presented above) because many of the assumptions
required for the simple calculation are not required for numerical modeling.
While the numerical model results support the hypothesis of complete capture, the numerical model in the
RI has not been updated to reflect current extraction rates.
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Overall Assessment of Capture
Based on the above information and analysis, there is not enough evidence to conclude that capture of the
TCE plume is complete. Also, USEPA currently has no control over the extraction rates at the wellfield.
The highest levels of contamination that are not captured may be relatively shallow (e.g., 20 ft bgs at
MW-09-ES compared to approximately 80 to 90 ft bgs for the supply wells).
5.2.3 GROUNDWATER CONTAMINANT CONCENTRATIONS
As concluded in the Second FYR, natural attenuation is not a significant process at the Site. Based on
concentration trends at the high-concentration monitoring wells (as presented in LTM reports), it appears
that it will take several decades, or longer, to achieve MCLs for TCE and PCE in the aquifer.
5.3 SHALLOW GROUNDWATER AND VI
5.3.1 GROUNDWATER DISCHARGE TO SURFACE WATER
Based on the Draft 2010 Subdrain System and Treatment Lagoon Status Report, the subdrain system has
been successful in achieving the ROD-specified performance criteria in the central portion of Rainier
Avenue, but not at the south end of Rainier Avenue where artesian conditions persist, and occasionally
not at the north end of the street at PZ-719. As a result, the two southern-most homes (5101 and 5103 SE
Rainier Avenue; air-sample locations #5 and #6) overlie groundwater shallower than 1.5 ft below the
base of the crawlspaces, increasing the potential for TCE and PCE concentrations in indoor air to exceed
ROD indoor air goals of 1.46 (ig/m3 and 4.38 (ig/m3, respectively. Groundwater beneath the northern-
most home (4901 SE Rainier Avenue; air-sampling location #1), sporadically is measured shallower than
3 ft in depth. Groundwater elevations have also been measured shallower than 3 ft in depth in other areas
of the neighborhood including at well MS-ES-09 northeast of the house at 5101 SE Rainier Avenue (air
sampling location #5); in the northwest corner of the neighborhood (PZ-719) in May 2010, and in the
southern portion of the neighborhood (PZ-725) in May 2010. Also, during the site visit the optimization
team was told of a home that operated a sump pump to remove standing water from the crawlspace
beneath the home (discharge location unknown). The home is located at 301 SE N Street between air
sampling locations #17 and #18. The Palermo team believes that several other instances of water in crawl
spaces have been reported.
The subdrain is also not effective in eliminating the surface seeps along the base of the bluff as envisioned
in the ROD.
The highest TCE detection from the October 2010 sample round was 130 (ig/L at well MW-ES-09 with a
depth to water of 0.33 ft below top-of-casing. TCE concentrations in shallow groundwater near the homes
at 5101 and 5103 SE Rainier Avenue (air sampling locations #5 and #6) are shown to be near 100 (ig/L
based on TCE contours using October 2010 groundwater data.
The subdrain water quality also provides an indication of seep and shallow groundwater concentrations.
PCE and TCE concentrations in shallow groundwater captured by the subdrain have trended differently
since 2001. PCE concentrations have decreased significantly, presumably due to PCE source area
remediation with the SVE system and continued groundwater flushing. TCE concentrations have
remained relatively consistent, with a recent decrease that might be associated with a decrease in flow.
Trend plots from the Draft 2010 Subdrain System and Treatment Lagoon Status Report document for
monitoring (cleanout) stations 357, 358, 359 and 360 are attached, showing the reduction of TCE and
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PCE concentrations with time. Figures 3-5 and 3-6 from the same report are also attached showing the
decrease in PCE and TCE concentrations with time.
Shallow groundwater depth and water quality are directly tied to concerns regarding VI. Expression of
contaminated seeps at the surface could also pose a risk to people working or playing near the ditches that
convey the contaminated water. The risks of dermal adsorption and ingestion were considered during the
RI risk assessment, but exposure to vapors for this exposure scenario was not.
5.3.2 VI POTENTIAL AND AIR QUALITY
The sporadic indoor air and crawlspace data collected to date make it difficult to establish the presence or
absence of a VI pathway above ROD goals. The homes at greatest risk for VI are the two southern homes
and one northern home along Rainier Avenue (street address numbers 4901, 5101, and 5103; air-sample
locations #1, #5, and #6). Other homes in the southwest portion of the neighborhood that overlie the
highest TCE concentrations in groundwater and homes in the east-central portion of the neighborhood
that overlie groundwater near 3 ft in depth are also at risk. One of these homes on N Street reportedly
used a sump pump to address standing water (301 SE N Street; between air-sample locations #17 and
#18; discharge location unknown).
Crawlspace to indoor air attenuation factors are difficult to establish due to factors including site-specific
differences in building construction and resulting air exchange, and background sources within homes.
Review of Palermo crawlspace and indoor air data shows attenuation factors varying from above 1 in a
few instances to 0.01, with most from 0.1 to 1, which is within the expected crawlspace to indoor air
range.
The evaluation of the potential for VI based on groundwater concentrations and depth to water is further
complicated by unknown performance standards. The 1999 ROD calls for achieving WSDOE Model
Toxics Control Act (MTCA) values in indoor air of 1.46 (ig/m3 for TCE and 4.38 (ig/m3 for PCE by
lowering the water table via a subdrain system. According to the Second FYR, 2001 changes in MSDOE
MTCA default values for indoor air resulted in lower indoor air thresholds of 0.022 (ig/m3 for TCE and
0.42 (ig/m3 for PCE. This suggests that the subdrain criteria might need to be more aggressive than that
suggested in the ROD. However, a comparison of observed groundwater concentrations and measured
indoor air concentrations from adjacent properties (Table 7-2 of the Second FYR) indicates that the
Johnson-Ettinger model may have been overly conservative in establishing the original performance
criteria. The calculated surface water/shallow groundwater (ponded crawlspace water) goals for
protection of indoor air are 0.027 (ig/L and 0.05 (ig/L for TCE and PCE, respectively, which are an order
of magnitude lower than the laboratory reporting limit. Modeling performed for the ROD predicted that
the average crawlspace water TCE and PCE concentrations of 19.55 (ig/L TCE and 20.25 (ig/L PCE
would result in indoor air concentrations of 408 (ig/m3 TCE and 687 (ig/m3 PCE. Actual indoor air
sample results have been two to three orders of magnitude lower than predicted values.
The potential VI pathway also exists in other areas of the Palermo Superfund site. In particular,
commercial lease spaces overlying and near the Southgate Dry Cleaners business have not been evaluated
using shallow soil vapor, sub-slab soil vapor, or indoor air sampling. Residual PCE impacts to soil and
groundwater in that area could result in a VI pathway. Subslab or shallow soil vapor, and indoor air
sampling would be necessary to further evaluate the potential VI pathway near the former PCE source
area.
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5.4 TREATMENT SYSTEM COMPONENT PERFORMANCE
5.4.1 PALERMO WELLFIELD AIR STRIPPERS
The groundwater treatment component of the remedy (air stripping) is effective. TCE and PCE do not
exceed MCLs in treated water. Furthermore, since air stripping is the City's preferred technology for pH
control, the air stripping remedy adds no cost or energy use to the water treatment plant operations at the
wellfield. Air stripping is also used at the City's Bush Middle School Wellfield even though no organic
contaminants are present there.
5.4.2 SUBDRAIN SYSTEM TREATMENT LAGOON
The treatment lagoon has been meeting performance criteria in reducing PCE and TCE concentrations in
water. The Second FYR references some issues with keeping the aerators operating, but City personnel
did not emphasize problems during the optimization team site visit.
5.5 REGULATORY COMPLIANCE
TCE and PCE concentrations in groundwater within the plume continue to exceed MCLs and likely will
exceed MCLs for many decades (or longer).
TCE and PCE are regularly reported in the treatment lagoon outfall and are occasionally detected in the
receiving water outfall (to the Deschutes River) but remain below the permitted limit.
TCE and PCE are regularly detected in indoor and crawlspace air within the Palermo neighborhood but
have remained below the allowable limit since December 2004 (with no data since May 2008). Most
indoor air detections fall within expected background concentrations, but sampling has been inconsistent
due to a variety of factors.
The commercial portion of the Site has not been fully evaluated for potential VI. The Southgate Dry
Cleaners lease space and adjacent lease spaces have not been tested for VI.
5.6 COMPONENTS OR PROCESSES THAT ACCOUNT FOR MAJORITY OF ANNUAL
COSTS
Detailed annual cost information that is representative of future costs is not available, in part because
much of the remedy operation is conducted by the City as part of routine public works efforts. For this
reason, annual costs are not discussed further.
5.7 APPROXIMATE ENVIRONMENTAL FOOTPRINTS ASSOCIATED WITH
REMEDY
Electricity and water usage associated with water supply well and air stripper operation are not considered
as part of the remedy for footprinting purposes because the wells are operated for public water supply
purposes, and the City indicates that the air strippers would operate regardless of the VOC contamination
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to adjust the pH of the water. The water diverted to surface water from subdrain operation likely has little
effect on water resources because of the potential for that water to be expressed as a natural seep in the
absence of subdrain operation. The remedy footprints for energy use, air emissions, water use, materials
use, and waste generation are predominantly associated with operation of the lagoon aerators, process
monitoring, and semi-annual groundwater sampling. These footprints are likely relatively small and
subject to substantial uncertainty given the lack of footprint information for laboratory analysis. Due to
the relatively small anticipated footprint and the uncertainty, the footprint has not been quantified for this
report.
5.8 SAFETY RECORD
The site team did not report any safety concerns or incidents.
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6.0 RECOMMENDATIONS
Several recommendations are provided in this section related to remedy effectiveness, cost control,
technical improvement, and site closure strategy. Note that while the recommendations provide some
details to consider during implementation, the recommendations are not meant to replace other, more
comprehensive, planning documents such as work plans, sampling plans, and QAPPs.
Cost estimates provided herein have levels of certainty comparable to those done for Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) FSs (-30%/+50%), and these cost
estimates have been prepared in a manner generally consistent with USEPA 540-R-00-002, A Guide to
Developing and Documenting Cost Estimates During the Feasibility Study, July, 2000. The costs
presented do not include potential costs associated with community or public relations activities that may
be conducted prior to field activities. The costs and sustainability impacts of these recommendations are
summarized in Tables 6-1 and 6-2.
Additional information and analysis is needed to belter define the effectiveness of the remedy in (1)
containing the groundwater TCE plume and (2) preventing unacceptable risks due to VI. Several
recommendations are provided in Section 6.1 to address these issues. The annual costs associated with the
current remedy are low, in part because the City currently operates and maintains the treatment systems at
no additional cost beyond routine public works costs. There may be an opportunity to slightly reduce
future annual monitoring and maintenance costs, as identified in Section 6.2. In Section 6.3, a few ideas
are presented for improving data management and presentation. Finally, recommendations related to
implementation of a site closure strategy are presented in Section 6.4.
6.1 RECOMMENDATIONS TO IMPROVE EFFECTIVENESS
6.1.1 EXPAND GROUNDWATER SAMPLING TO BETTER DEFINE THE PLUMES AND TO
INFORM AN UPDATED CAPTURE-ZONE EVALUATION
Additional groundwater data are needed to define and confirm the shapes of the current PCE and TCE
plumes, both horizontally and vertically. An expanded sampling event is recommended that includes all
of the LTM sampling points plus additional existing sampling points to better delineate the current
plumes. In particular, the following additional sampling points are recommended (marked in Exhibits A-3
and A-5 in Attachment A):
• Existing shallow piezometers (as available and accessible) in the Palermo neighborhood (in
addition to the three that are routinely sampled), particularly:
o PZ-719, PZ-726, PZ-730, PZ-731, and PZ-722 to define the northern and eastern TCE
plume extents;
o PZ-720, PZ-727, PZ-722, PZ-725, and PZ-729 for additional resolution of the high-
concentration portion of the TCE plume; and
o PZ-716, PZ-712, PZ-709, and PZ-708 west of the homes to try to identify locations of
high PCE and TCE at the valley bluff;
• Five wells at the current WSDOT MTL property: MW-102, MW-103, WSDOT-MW-1,
WSDOT-MW-2, and MW-ES-11;
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• Existing City of Tumwater Wells that may assist with plume delineation:
o TW-58, which is northeast of the Palermo neighborhood;
o TW-8, which is one of the production wells in the Palermo Wellfield;
o MW-4A and MW-4B which are northwest of the Palermo Wellfield;
o A well south of the Palermo neighborhood that may be helpful for defining the southern
extent of the plumes (possibly named MW-93-03);
o A well located on the valley bluff near the southwestern corner of the neighborhood; and
o Wells along Linda street south of the Palermo Wellfield; and
• Groundwater seep locations near the bluff, particularly in ditches behind (east of) the home at
4905 Rainier Avenue (Air Sample Location #1) and south-southeast of the home at 5103 Rainier
Avenue (Air Sample Location #6).
The actual well locations and depth details should be field verified and locations should be adjusted as
needed to achieve the goal of more complete delineation.
Also, there is a well in the parking lot south of the Southgate Dry Cleaners that has not been sampled
because it has been found to be damaged. If it is possible to repair the well or sample the well using
alternative procedures, this should be attempted because the well could be a valuable data point for
establishing the southern boundary of the TCE plume.
The results from the expanded sampling event should be used to update the LTM program to focus on the
wells/piezometers that provide the most important information for: (1) understanding concentration
trends; and (2) ensuring plume expansion does not occur. It may be helpful to repeat expanded sampling
for one or two additional rounds before setting on a new LTM program. For these additional, expanded
sampling events, the wells to sample should be adjusted based on results obtained in prior sampling.
Also, the results of the first expanded sampling event should be used to determine whether additional
monitoring wells are needed and, if so, where. It is likely that additional shallow (water table)
groundwater wells will be needed east of the Palermo neighborhood to define the eastern extent of the
TCE plume. Recommended locations (subject to change based on new data) are near MW-110, near TW-
58, and 300 ft south of MW-110. Also, if the well in the parking lot south of Southgate Dry Cleaners
cannot be sampled, a new well should be installed to define the southern plume extent. Likewise, a new
well near the location of abandoned well MW-ES-01 (which had elevated TCE concentrations during the
RI) will likely be helpful to establish the northern extent of the plume.
It will also helpful to install a monitoring well nest immediately downgradient of the Southgate Dry
Cleaners site (southwest of MW-ES-06) to better determine whether PCE has effectively been flushed
away from that source (see also Section 6.1.7); both shallow and deep monitoring points are
recommended at that location to also assess TCE and PCE concentrations at depth. Similarly, if sampling
data from the existing wells is unclear, an additional monitoring point at the current WSDOT MTL may
be helpful to assess if TCE has been flushed from that source area.
In addition to the water quality sampling mentioned above, additional water level data should be collected
over a wide regional area to better define the potentiometric surface as affected by pumping at the
Palermo Wellfield. This includes collection of water levels at all sampled wells, wells on the golf course
east of the neighborhood/wellfield, City wells south of the TCE plume, and any other accessible wells to
better define the regional potentiometric surface. If a well in the wellfield has been non-operational for a
reasonable period of time, that well may be valuable as a head measurement point also. Ultimately, it may
be useful to install one or two piezometers within the wellfield property (e.g., between TW-5 and TW-2).
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Analysis of the potentiometric surface should be performed in a low-water-demand month (October-
April) and should be repeated in future years. A one-time analysis of the potentiometric surface in a high-
water-demand month (July-August) would provide useful information for comparison.
The estimated additional cost for each expanded sampling event is $25,000 and includes 7 days of
sampling at $2,500 per day plus 38 additional sample analyses (including quality assurance [QA]) at $50
each.
If five wells are installed, the estimated cost will be $71,000. That includes $10,000 for plan
development, $10,000 per well for drilling, installation, and oversight, $10,000 for an installation report,
and 20 sample analyses (groundwater, soil, and QA) at $50 each.
6.1.2 UPDATE CAPTURE-ZONE ANALYSIS
A new capture zone analysis should be conducted after the next sampling event using regional head data
and more spatially extensive concentration data. The capture zone analysis should include:
• Development of a regional potentiometric surface for the upper aquifer (see prior
recommendation) with a graphical interpretation of the capture zone, if possible;
• Evaluation of concentrations east, northeast, and southeast of the Palermo neighborhood
(downgradient from the target capture zone); and
• Numerical or analytical flow modeling of capture using the best available estimates of aquifer
transmissivity and wellfield pumping.
If available, the existing RI groundwater model may be adapted for use in this analysis.
The optimization team estimates that the costs for a rigorous capture zone analysis with this new data
would be approximately $50,000 assuming the RI groundwater model is available. This is based on an
estimate of 400 hours (10 full-time person-weeks) of labor at an average labor rate of $125 for
groundwater modelers, management, and clerical/drafting support. This estimate includes some minor
updates to the model and recalibration, but not extensive model reconstruction.
6.1.3 RENEW AND IMPROVE INDOOR AIR SAMPLING PROGRAM IN PALERMO
NEIGHBORHOOD
The sporadic indoor air and crawlspace data collected to date make it difficult to establish the presence or
absence of a VI pathway above ROD goals. The homes at greatest risk for VI are the two southern homes
and one northern home along Rainier Avenue (street address numbers 4901, 5101, and 5103; air sampling
locations #1, #5, and #6); the homes in the southwest portion of the neighborhood that overlie the highest
TCE concentrations in groundwater (which includes the two southern homes on Rainier Avenue), and
homes in the east-central portion of the neighborhood that overlie groundwater near 3 ft in depth,
including one home at 301 SE N Street (between air sampling stations #17 and #18), that reportedly
operates a sump pump (discharge location unknown).
As a first step, a survey of crawlspace conditions should be conducted, including presence/absence of a
crawlspace, crawlspace height/depth and degree of saturation, and presence/absence/condition of any
vapor/moisture barrier. This should be coupled with crawlspace and indoor air sampling to better assess
the VI pathway and determine if active remediation is needed for homes (see next recommendation,
Section 6.1.4).
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Soil vapor samples are typically collected as part of a VI assessment. However, the shallow groundwater
in the neighborhood makes collecting soil vapor samples difficult to impossible because soil pores are
saturated with water. In the absence of soil vapor data groundwater, crawlspace air and indoor air samples
are needed. Crawlspace air and indoor air data fluctuate with weather conditions and other factors such as
air exchanges in the buildings, and the potential presence of background sources. As a result several
sample rounds are best when relying on crawlspace and indoor air data.
According to the Second FYR the current default WSDOE MTCA Method B indoor air cleanup levels for
TCE and PCE are 0.022 (ig/m3 and 0.42 (ig/m3, respectively, which (according to MTCA assumptions)
equates to a 1 x 10"6 excess cancer risk. The ROD indoor air cleanup goals for TCE and PCE are 1.46
(ig/m3 and 4.38 (ig/m3, respectively, which fall within USEPA's acceptable risk range of 1 x 10"4 to
1 x 10"6 excess cancer risk. WSDOE is presently considering updates to MTCA standards for TCE and
PCE.
Published background concentrations of TCE and PCE in indoor air (June 2011 USEPA 530-R-10-001)
are described as highly variable, and the range of the 50th percentile for TCE and PCE are non-detect to
1.1 (ig/m3 and non-detect to 2.2 (ig/m3, respectively. The upper ends of these background ranges exceed
most of the Palermo neighborhood indoor air detections.
Regardless of the depth to shallow groundwater, the potential for VI to result in indoor air concentrations
of TCE and PCE above cleanup goals remains as long as the shallow groundwater contains elevated
concentrations of TCE and PCE. Some homes may not have crawlspaces and in those cases the risk for
elevated indoor air concentrations of TCE and PCE may be greater, depending on construction
characteristics of the slab, sealing of slab penetrations, and presence/absence/characteristics of a moisture
barrier beneath the slab.
Additional periodic sampling of crawlspace air and living-space air is recommended until it is reasonably
established that indoor air concentrations meet ROD goals at all houses. Modeling of indoor-air
concentrations has significantly overestimated actual concentrations of PCE and TCE historically
observed and should therefore not be used as a primary means of effectiveness demonstration.
Summa canisters are generally considered the standard for collecting ambient air samples for low
reporting limit applications. The low-flow regulator allows an integrated sample to be collected over the
sample duration (24 hours for residential applications). Other ambient air sampling approaches are
available in addition to Summa canisters, although those applications are typically weighted more toward
an initial stage of an investigation for a problem/no-problem evaluation as opposed to quantifying very
low VOC concentrations, such as those at the Palermo site. For example, one passive diffusive sampling
design under the trade name "Radiello" passively uptakes VOCs by chemical sorption, and an ambient air
concentration is calculated as opposed to a simple flux. However, Summa canisters may provide more
detailed low-concentration quantification. Additional research of alternate sampling approaches and costs
can be performed during workplan preparation.
The approximate costs for the recommended additional air sampling are:
• $26,000 for the planning phase, including a workplan ($10,000) community survey/outreach
($10,000), and building survey ($6,000: 2-person crew at $l,500/day for 4 days);
• $6,000 per sample event for sampling, including 4 days for a 2-person crew at $l,500/day;
• $11,000 per sample event for laboratory analysis, assuming 25 homes sampled, 25 crawlspace
samples, 35 indoor air samples (10 homes with two samples), two outdoor ambient samples, and
eight duplicate samples (70 samples total) for TO-15 Selected Ion Monitoring (SIM) analysis at
$150/sample;
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• $10,000 per sampling event for data review and reporting.
Thus, the initial sampling is expected to cost approximately $53,000. Subsequent events would not
require the planning tasks and would be expected to cost approximately $27,000 each. If a total of four
annual events are conducted, the total (undiscounted) cost would be approximately $134,000. Four events
should provide: (1) enough information to determine that VI is not an issue at certain homes; and (2)
information sufficient to assess mitigation system performance at any homes where mitigation is needed
and installed, assuming that installation occurs after the second sampling event (see next recommendation
in Section 6.1.4).
6.1.4 INSTALL MITIGATION SYSTEMS IF/AS NEEDED AT NEIGHBORHOOD HOUSES
Active remediation will be necessary if indoor air TCE or PCE concentrations exceed target cleanup goals
and groundwater remains shallow and impacted. Typical mitigation measures for existing residences are
based on radon mitigation systems. Three candidate systems are as follows:
1) Subslab Depressurization System - This system is generally the most practical for slab-on-grade
foundations where a permeable vadose (unsaturated soil) zone is present. For this system, one or
two suction pits are excavated adjacent to the slab and piping extends from the pits to above the
house for venting. The venting location needs to be away from windows to prevent vapors from
entering the structure. A small in-line fan is used to draw air from below the slab, creating a
pressure differential across the slab to prevent migration into the structure. Installation costs range
from $1.00 - $2.50/ft2 for homes (January 2007 Vapor Intrusion Pathway document, by the
Interstate Technology & Regulatory Council Vapor Intrusion Team; and July 2009 Proposed Plan
for Vapor Intrusion Pathway, MEW Superfund Site, Mountain View and Moffett Field,
California). For a 2,000 ft2 house, installation costs would range from $2,000 - $5,000. Annual
electrical costs are incurred. Limitations include clayey soils and saturated soils. The presence of
crawlspaces in the Palermo neighborhood and the saturated ground conditions significantly
reduce the effectiveness of this approach.
2) Submembrane Depressurization - This system is generally used when crawlspaces are present
and can be accessed and where a vadose zone is present. This system has been shown to be very
effective. A membrane is loosely placed across the floor of the crawlspace and sealed along the
perimeter and around pipe penetrations. The membrane can be polyethylene material or plastic
sheeting. An extraction pipe is placed below the membrane, extending above the house. An in-
line fan creates low pressure beneath the membrane. Low permeability soils may require
additional extraction locations under the membrane. Costs range from $1 - $9/ft2 ($2,000 -
$18,000 for a 2,000 ft2 home). Higher costs are due in part to sealing cracks and penetrations in
the floor. Annual electrical costs are incurred. The membrane requires monitoring to ensure it
remains sealed and is not damaged.
3) Crawlspace Ventilation Causing Pressurization - This system is used in instances when the
crawlspace is partially enclosed and air circulation is poor, and when the crawlspace cannot be
accessed to place a depressurization membrane. Air is pushed into the crawlspace by a fan to
increase crawlspace air pressure and dilute concentrations of VOCs present in the crawlspace.
Soil vapor is forced away from the area of high pressure and is less likely to enter the crawlspace.
Cracks and floor penetrations must be sealed to prevent short-circuiting and introduction of air
from the crawlspace into the home. In cold climates, water and sewer pipes in the crawlspace
must be wrapped to prevent freezing. During periods of cold weather, introduction of cold air into
the crawlspace may result in added heating costs for the home. Costs for these systems are not as
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well documented as the two common approaches discussed above. Installation costs would be
expected to be on the order of $2 - $3/ft2 for homes ($4,000 - $6,000 per home based on a 2,000
ft2 house). This includes $750 - $1,000 for a fan and louvers, and one or two days for installation
and sealing at $2,000/day for a 3-person crew.
While advantages and disadvantages of all options should be considered on a house-by-house basis,
conditions in the neighborhood suggest that option 3 may be the only practicable option for mitigation (if
needed) where groundwater is very shallow and crawlspace clearance is very limited. For this option, the
fan can be designed based on exchanging the air volume in the crawlspace about 15 times/hour.
Assuming a 1.5-foot tall crawlspace across a 2,000 ft2 foundation (= 3,000 cubic ft x 15
exchanges/hour/60 minutes) a 750 cubic feet per minute (cfm) fan would be appropriate. A smaller sized
fan to achieve fewer air exchanges per hour may still provide adequate ventilation. The 750 cfm fan
would be very low HP and electrical costs for a 1/30 HP fan should be less than $10/month. Costs for the
fan and louvers for the vents would be expected to total less than $750. With sealing cracks and floor
penetrations, insulating pipes, and installation, an estimate of $2 to $3/sq. ft. is reasonable. The fan must
continuously operate to provide the positive air pressure and ventilation in the crawlspace. If the fan stops
working, moisture could build up in the crawlspace due to the louvers preventing circulation, potentially
causing an environment suitable for mold growth.
6.1.5 EVALUATE OPTIONS AND PRACTICABILITY FOR LOWERING THE WATER TABLE
AT THE BLUFF AND THROUGHOUT THE PALERMO NEIGHBORHOOD
The subdrain system has not eliminated discharge of groundwater to the surface as envisioned in the
ROD. A feasibility-level evaluation of potential methodologies to eliminate surface discharge should be
undertaken. Options to consider may include (but should not be limited to):
• Installation of an additional (or expanded) subdrain system to intercept shallow groundwater
before discharge; or
• Groundwater extraction from deeper intervals (~ 100 ft bgs) near the bluff, with water potentially
piped to the existing Palermo Wellfield treatment system (directional drilling may be considered).
The optimization team finds it more likely than not that active pumping will be needed to provide a
meaningful result, particularly for reducing existing seeps and for addressing the water table in the
southwestern portion of the Palermo neighborhood. The southern portion of the subdrain is the highest
portion of the subdrain because adequate elevation is required to allow gravity flow through the rest of the
drain to the lagoons for treatment.
In conducting this evaluation, the effect of these options on overall TCE plume capture should be
estimated, especially if the capture-zone analysis (as explained in a prior recommendation, Section 6.1.2)
suggests that the TCE plume is not being completely captured.
If extracted water cannot be piped to the existing Palermo Wellfield system for treatment and input into
the water supply, considerations will be needed to provide treatment because the existing lagoon will
likely not have sufficient capacity to provide the necessary treatment. An expansion of this lagoon may be
feasible.
Use of the existing numerical groundwater flow model, or a new groundwater flow model, would likely
be helpful for this exercise. The evaluation may result in a conclusion that elimination of surface
discharge is not practical and necessary. In this case, the remedy documentation should clearly reflect the
decision to allow surface discharge.
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The feasibility analysis should also reassess whether a more aggressive and active cleanup strategy is
warranted in the upland areas (e.g., in source areas and areas of relatively high PCE and TCE
concentrations) based on the additional data collected. Such a strategy could be considered if it would
accelerate the time to attain MCLs throughout the aquifer. However, the optimization team is not
optimistic that a practical and cost-effective strategy can be deployed in the upland areas due to plume
size and natural aerobic conditions (which limits biodegradation potential).
The optimization team estimates that the cost for this type of analysis would be on the order of $30,000
assuming the RI model is available for use with relatively minor modifications. This is based on an
estimate of 250 hours of labor at an average labor rate of $115 for engineers, scientists, modelers,
management, and clerical/drafting support.
6.1.6 ASSESS VI AT SOUTHGATE SHOPPING CENTER
The commercial portion of the Site has not been fully evaluated for potential VI. The Southgate Dry
Cleaners lease space and adjacent lease spaces have not been tested for VI. Sub-slab soil vapor samples
and indoor air samples from the dry cleaning lease space and two adjacent lease spaces (which are close
to the source area and may share the same slab foundation), and ambient outdoor air samples to assess
background conditions, should provide sufficient data to evaluate whether there is a potential for VI in the
Southgate Shopping Center. If the dry cleaning business is active and using PCE, then an indoor air
sample would not be collected at that facility because the sample result would reflect the routine chemical
use in that commercial lease space.
No VI evaluation is proposed outside the existing building footprint at this time, pending results from the
source area and adjacent lease space results. If the source area and adjacent lease space evaluation results
indicate that VI is not a concern, then further assessment outside the building footprint should not be
necessary. If sub-slab results exceed screening criteria then a broader soil vapor survey can be planned to
include surrounding areas and to include sampling both sub-slab and adjacent to buildings.
The optimization team estimates that the cost for implementing this recommendation is approximately
$35,000, including:
• $10,000 for a work plan, including visiting the Site, selecting sample locations, preparing the
work plan, and preparing the health and safety plan;
• $10,000 for field work, including coring six cores (two in each of three lease spaces) and
installing six soil vapor monitoring points (6-inch long #50 mesh stainless steel screen at a depth
of Ifoot beneath the base of the slab, connected to %-inch tubing). The vapor monitoring points
are placed within a 3-inch diameter hand augered boring through a 4-inch diameter hole cored
through the slab. Sand is placed around the screen and the upper portion of the borehole sealed
with bentonite. A brass ball valve is connected to the tubing. A hose barb for soil vapor sampling
is attached to the top of the ball valve. A utility cover is placed over the core. The vapor
monitoring points are allowed to equilibrate over a minimum 2-day period prior to sampling.
Field QA for sampling is assumed to be the helium shroud method. An alternative is using a
Freon spray (dust off spray) along all connections. One to 2 days in the field for one staff member
to install the probes, and 1 to 2 days in the field for two staff members to sample the probes and
abandon the boreholes are assumed. Field work also includes collecting one ambient air sample
inside each of the three lease spaces, and one outdoor ambient air sample. Equipment includes 1-
L Summa canisters for the soil vapor samples and 6-L Summa canisters for the ambient air
samples. The probe installation cost does not include local boring permit fees, if any. The cost
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includes project-management time and coordinating with tenants and the landowner. The cost
does not include working on procuring an access agreement, if necessary.
• $5,000 in laboratory fees for six USEPA Method TO-15 direct inject for subslab VOC analyses
and six helium analyses (if the helium shroud field QA method is used) using Modified ASTM
Method D-1946 and four ambient air samples for SIM analyses, plus possible duplicate samples
and possible repeat sampling prior to abandoning boreholes.
• $10,000 for preparation of a report presenting sample and QA protocol, tabulating results and
discussing findings.
6.1.7 EVALUATE SVE EFFECTIVENESS AND IMPLEMENT CONTROLS AS NEEDED
The Southgate Dry Cleaners SVE system was shut down in June 2000 after it had removed approximately
424 Ibs of PCE from the vadose zone. The system was shut down due to diminishing returns: the rate of
PCE removal at the time of shutdown was very small compared to removal rates measured in the first few
months of operation. At the time of shutdown, a single effectiveness-assessment soil sample was collected
in the SVE area at a location near where relatively high soil concentrations had been measured prior to
SVE operation. The PCE concentration in that soil sample was approximately 200 (ig/kg, which exceeded
the soil RG of 85.8 jig/kg.
While it is clear that the SVE action at the Southgate Dry Cleaners reduced the potential for PCE
migration to groundwater, it has not been demonstrated that the SVE system met the RG. While
additional soil sampling could potentially be done to confirm that most of the soil meets the RG (or the
RG is met on average), such an exercise is not recommended for the short term.
Rather, it is recommended that a water-table well be installed just to the east-northeast of the PCE source
area to determine if groundwater concentrations are elevated. This new well should be monitored as part
of the LTM program to determine if a significant PCE source is present (i.e., increasing or high-and-
stable concentration). Also, the indoor sub-slab Vl-assessment sampling that is recommended for this area
will help in determining if a significant mass of PCE remains in the vadose zone.
Per the ROD, unless and until it is demonstrated that vadose-zone PCE poses no threat to groundwater,
deed restrictions should be placed on the Southgate Shopping Center property to prevent future actions on
the property that could exacerbate transfer of PCE in soil to groundwater. Such deed restrictions would
specify, for instance, that the asphalt surface (or similar low-infiltration surface) remain in place and be
maintained by the property owner and that a program be implemented to reduce or eliminate any water
infiltration in the PCE source area. Other ICs may also be needed if it is determined that other exposure
scenarios (e.g., involving subsurface construction work) pose potentially unacceptable risks.
The cost for well installation is included with the costs in Section 6.1.1. The cost of performing an
effectiveness evaluation (desktop study) plus legal costs to implement the deed restriction are estimated to
be $15,000.
6.1.8 MAKE AN AGREEMENT WITH THE CITY FOR CONTINUED OPERATION OF THE
PALERMO WELLFIELD IN A MANNER NEEDED TO ENSURE CAPTURE
The City is presently under no obligation to maintain production rates at the Palermo Wellfield that
ensure hydraulic containment of the TCE plume. Production-rate data provided by the City show that
pumping at the wellfield has declined substantially in recent years. After completion of the capture-zone
evaluation recommended above, USEPA should enter into an agreement with the City requiring operation
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of the wells at rates deemed sufficient for capture, provided that the required rate is within the wellfield
water right of approximately 1,900 gpm as an annual average (HDR, 2011).
It is assumed that the City will be amenable to such an agreement and that only minimal legal costs will
be incurred (approximately $5,000). It should be noted that appropriate technical and legal factors need to
be considered in developing such an agreement.
If increased pumping is needed, there may be technical challenges associated with higher extraction rates
(e.g., well-screen fouling or intra-well drawdown interference) that would need to be overcome through
engineering design and implementation. One or more new strategically-located extraction wells may be
required. Also, mandated increased pumping could result in excess supply, especially during winter (low-
demand) months. In that case, USEPA should work with the City to ensure best use of extracted
groundwater and, if necessary, should ensure that any discharge of unused water occurs in a cost-effective
and non-detrimental way.
Also, the City of Tumwater, together with the City of Olympia and the City of Lacey, is currently
beginning a project to utilize an additional groundwater right (1,400 gpm annual average) that had
belonged to a now-defunct brewery. Wells that had been used for this water right are generally east of the
Palermo Wellfield. If additional groundwater extraction is needed for plume containment, it is likely that
the contemplated development and extraction at wells just to the east of the Palermo neighborhood would
be beneficial for plume capture.
6.2 RECOMMENDATIONS TO REDUCE COSTS
Annual costs for this site include only groundwater monitoring and subdrain system performance
evaluations. Thus, opportunities for cost savings are limited. However, as discussed below, there is at
least one opportunity to reduce annual costs.
6.2.1 REDUCE SAMPLING FREQUENCY AT SELECT MONITORING WELLS
Semi-annual sampling is presently conducted for 21 groundwater monitoring locations. The number of
sampling points should remain about the same (but the specific locations may change) after completion of
the expanded sampling events recommended in Section 6.1.1. However, for most of the LTM points,
sampling frequency can be decreased. Semi-annual sampling should continue for points that are needed to
establish that the plume is not expanding and for points that are used to determine concentration trends for
the high-concentration portions of the plumes. For the remaining monitoring points, annual sampling is
recommended.
The one-time cost to update the LTM program documents is estimated to be $5,000. The reduced
frequency of sampling should save approximately $5,700 per year (2 fewer days at $2,500 each + 15
fewer samples at $50 each). The reduction in monitoring costs will not occur until the new LTM program
is established, which may not occur for one to two years.
6.3 RECOMMENDATIONS FOR TECHNICAL IMPROVEMENT
A few recommendations are provided that could help in managing data associated with the Site and with
assisting future evaluations.
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6.3.1 MONITORING REPORTS
Monitoring reports should identify the well-screen elevation intervals for all wells sampled. In addition to
PCE and TCE concentration contour maps, cross-section maps would be useful for showing plume shape.
If data indicate significant depth variability of the plumes, and this is not clear from cross sections, plume
maps for different elevations or depths may be useful.
Also, as described in Section 6.1.1, regional potentiometric surface maps should be generated, at least
annually, and at least for the water table (other aquifer-specific surfaces may also be useful). These maps
need to cover an area much larger than the TCE plume and coordination with the City and State agencies
will likely be required. These contour maps will be useful for defining the capture zone of the Palermo
Wellfield and for determining the depth to water throughout the Palermo neighborhood.
These changes should have minimal effect on annual costs.
6.3.2 WELL-FLOW REPORTING SYSTEM
Extraction rates and total extracted volumes for each well at the Palermo Wellfield should be reported on
a regular basis to USEPA, no less frequently than monthly. This should have minimal effect on annual
costs.
6.3.3 DATA MANAGEMENT SYSTEM
Data from the Site, including relevant data collected by City and State agencies and contractors, should be
entered into an electronic data management system to improve data availability and accessibility. This
will improve the efficiency for any future evaluations at the Site. The cost for setting up the data
management system should be less than $10,000. Management of the system will require some labor, but
it is expected that additional labor costs will be entirely offset by improved efficiency in annual reporting
of analyses.
6.4 CONSIDERATIONS FOR GAINING SITE CLOSE OUT
The effectiveness recommendations listed in Section 6.1 were selected because they are likely to be
helpful in initiating progress toward Site Closure. Additional closure-related recommendations are
provided below.
6.4.1 SUGGESTED CLOSURE STRATEGY
The active remediation systems (wellhead air stripping and subdrain system operation) at the Site appear
to be functioning and providing benefits. These remediation measures should therefore be continued.
As indicated in Sections 6.1.3 and 6.1.4, VI should be reassessed and mitigation measures should be
installed if/as necessary.
As indicated in Section 6.1.5, additional measures should be evaluated for elimination of surface
discharge. The possible actions include:
• No additional action;
• New wells for City (deep, possibly non-vertical); and/or
39
-------
• Expanded subdrain system (e.g., using deeper and/or larger diameter pipes).
If the recommended capture-zone analysis indicates that the TCE plume is expanding, additional
remediation measures will need to be considered to address that condition.
Once these recommendations are implemented, the path to site closure will be clearer and may focus on
continued monitoring until all RGs are met (likely decades).
6.4.2 MODIFY THE REMEDY
After implementing the recommendations of Section 6.1 (as well as recommendations from the Second
FYR Report), it will likely be prudent to issue a ROD Amendment, Explanation of Significant Difference
(ESD), or similar document to the update and clarify the remedial strategy and goals. In particular, the
new remedy document should:
• Establish that the VI pathway is evaluated primarily using air concentration data rather than
groundwater-depth and partitioning models;
• Clarify that biodegradation appears to be minimal and thus natural attenuation is not a significant
component of the remedy;
• Clarify the area of the TCE plume that is under control and being managed; and
• Estimate the time to achieve all cleanup goals (likely decades).
6.5 RECOMMENDATIONS RELATED TO GREEN REMEDIATION
The current remedy has a very low environmental footprint. No green remediation recommendations are
provided.
6.6 SUGGESTED APPROACH TO IMPLEMENTING RECOMMENDATIONS
The suggested order for implementing recommendations, along with estimated cost information, is
provided in Table 6-1. The first step should be to conduct the expanded groundwater sampling event.
Many of the additional evaluations and actions will depend on the results obtained from that event.
The overall cost effect of implementing these recommendations is expected to be an increase in costs for
this Site on the order of a few hundred thousand dollars (present-value). The highest costs are associated
with addressing the VI pathway in the Palermo neighborhood and are uncertain. In the costs presented in
Table 6-1, it is assumed that 2 years of air sampling will be conducted in the neighborhood, then
mitigation measures will be implemented at 20 homes, then an additional 2 years of air monitoring will be
conducted.
If it is determined that additional groundwater remedies are needed for plume capture or seepage control,
additional costs beyond those presented here will be incurred.
40
-------
Table 6-1. Cost Summary Table
Recommendation
Expanded Sampling Event (6.1.1), assume two, six months apart
Implement Technical Improvement Recommendations (6.3.1-6.3.3)
Assess VI at Southgate Mall (6. 1 .6)
Conduct Capture-Zone Evaluation (6. 1 .2)
Install and Sample Additional Wells (6. 1 . 1 & 6. 1 .7)
Implement Neighborhood Air Sampling Program (6. 1.3), four years
Enter Agreement with City (6. 1 .8)
Evaluate SVE Effectiveness and Implement Controls (6. 1 .7)
Evaluate Options for Lowering Water Table (6. 1.5)
Reduce LTM Frequency (6.2.1)
Execute Indoor Air Mitigation (if/where needed) (4. 1 .4)
TOTAL
Additional Capital
costs ($)
$50,000
$10,000
$35,000
$50,000
$71,000
$26,000
$5,000
$15,000
$30,000
$5,000
$100,000
$397,000
Estimated Change in
Annual Costs ($/yr)
$0
$0
$0
$0
$0
$27,000
$0
$0
$0
($5,700)
$120
$21,420
Estimated Change in
Life-Cycle Costs $*
$50,000
$10,000
$35,000
$50,000
$71,000
$134,000
$5,000
$15,000
$30,000
($109,000)
$102,400
$393,400
Discounted Estimated
Change in Life-Cycle
Costs $**
$50,000
$10,000
$35,000
$50,000
$71,000
$126,000
$5,000
$15,000
$30,000
($80,000)
$102,000
$414,000
* Includes capital cost plus 20-years of annual cost changes (no discout rate), except neighborhood air sampling continued only for 4 years
** Dicount rate of 3% applied to annual costs
41
-------
ATTACHMENT A
-------
EXHIBITA-1
VANCOUVER
ISLAND
BELLINGHAM
EVERETT
SEATTLE
TACOMA
TUMWATER
PROJECT
SITE
A
NT
VICINITY MAP
NO SCALE
LEGEND
ROADS/HIGHWAY
BUILDINGS
DRINKING WATER WELL SAMPLED
DRINKING WATER WELL NOT SAMPLED
-ES-05|^ MONITORING WELL SAMPLED
10I^S MONITORING WELL NOT SAMPLED
lpz-721ln PIEZOMETERS SAMPLED
• PIEZOMETERS NOT SAMPLED
APPROXIMATE AREA OF PALERMO WELLFIELD SUPERFUND SITE
TUMWATER, WASHINGTON
DATE: 10;24/08 12:29pm FILE: BR2328007P004TAN07_F1-1
ISBB
400'
SCALE IN FEET
PALERMO NEIGHBORHOOD BOUNDARY
SOURCE:
QUALITY ASSURANCE PROJECT PLAN
SAMPLING AND ANALYSIS FOR O&M OF SUBDRAIN SYSTEM
(URS, 2000)
Figure 1-1
Palermo Wellfield Super-fund Site
Long-Term Monitoring
Project Location Map with
Monitoring Well Locations
-------
-EXHIBITA-2a
Note: This figure was printed in color; information may
be missing from black and white photocopies.
rrr: Roads/Highway
Buildings
Fence
Surface Water/
Seep Sample
Drinking Water Well
Hand Auger
Geoprobe
M!Ha9 Monitoring Well
RI/FS Geoprobe
Location/ID
RI/FS Well Location/ID
Soil Boring
Polcrmo Wellfield Superfund Site
Tumwater, WA
ARCS EPA
REG»N 10
URS Gre/ner
Figure 4-8
Cross-Section Location
-------
(w«t)
180'
160'
140'
120'
100'
Screen Interval
Legend
EXHIB IT A-2b
Southgote Brewery City Pizza
Valley (East)
A'
X Groundwater Surface i
T May 1998 *"' (""/^ TCE
I Wat»r (ug/l) TCE PCE
Approximate Vertical Extent ^"•" l*^^™
Palermo WellfieU Superfund Site
Tumwater, WA
ARCS EPA
REGION 10
Vertical Scal«: !"=20'
Horizontal Scal«: 1"=200'
URSGrelner
180'
160'
140'
120
100
OT
•s.
Figure 4-9
Section A-A'
Showing Select PCE and TCE Soil &
Groundwater Analytical Results
-------
EXHIBIT A-3
LI FT STATION
CONTROL BUILDING
CONNECTION OF
DRAIN PIPE TO
TREATMENT
LAGOON
LOCATION
—*- -TIGHTLINEPIPE
209^
#23
TYPE 2 CATCH BASIN !(TYP) rf
T~^-^J*r.. • —-""u - ^s2
|_PZ-70 i PZ-701
CITY OF TUMWATER
MUNICIPAL
GOLF COURSE
CAPITOL 5000
PROPERTY
FINGER DRAIN (TYP)~
SURFACE WATER CHANNEL
FLOWS TO NORTH
xV-sSsssw' - • I1"' M •* '
%%TRUNK DRAIN ALIGNMENT
\\\m :m\\<\
PALERMO NEIGHBORHOOD
CITY OF TUMWATER
PALERMO WELLFIELD
\ \ \.,,\ \ \ 'H'V'X , '. '. •. f-V • 4tf
SUBDRAIN SYSTEM,V
DATE: 06/1 6/08 3, rpm FILE: B232a007P041TFR01F-03
207l STREET ADDRESS NUMBER
SOURCE:
QUALITY ASSURANCE PROJECT PLAN
SAMPLING AND ANALYSIS FOR O&M OF
SUBDRAIN SYSTEM (URS, 2000)
PIEZOMETER TO SAMPLE FOR
EXPANDED SAMPLING EVENT
0 5Q.
SCALE INF ••:• \
PART OF EXISTING LTM
NETWORK
Figure 7-1
Palermo Wellfield Super-fund Site
Second Five-Year Review
Indoor Air Sampling Locations
-------
EXHIBITA-4
^Sanitary Sewer Lift
/ Station "Wet Well" giw-23
-^Sanitary Sewer Lift
S Station Control Building
GTW-24
Drainage
Ditch
Capitol
5000 Bldg
Former Singer's l^
Gull Station
BARNES LAKE
City of Tumwater
Municipal Golf Course
Brewery
City Pizza
Drainage
Ditch
-ES-09 "0" St
Palermo
Neighborhood
MW-ES-03
1125.081
lo.soul (N
Overall Groundwater
Flow Direction
Palermo
Wellfield
Chevron Station -\
Southgate
Cleaners
Texaco Station
TrosperRoad—
— Palermo
Valley Bluff
/— Poage's Towing
and Auto Repair
Former WDOT
Facility
East Lee St
WDOT District
Maintenance Facility
Parametrix DATE:
1/6/2011 10:19 AM FILE:
BR2328007P004TAN07_OCT F2-3 LEGEND
300
SCALE IN FEET
Roads/highway
I , Buildings
TW~8O Drinking Water Well
X Piezometer
Monitoring Well Sampled
Monitoring Well Not Sampled
Groundwater Elevation (ft)
PCE Value (ug/l)
NOTES
1. Overall Groundwater Gradient =0.015 Vertical Feet Per Linear Foot.
2. Highlighted PCE Values Used To Generate Contours.
3. PCE at concentrations exceeding 5 ug/L has been detected in the
subdrain system west of Rainier Avenue. These concentrations were not
included when developing the isoconcentration contour lines for PCE.
Figure 2-3
Palermo Wellfield LTM
Piezometric Contour Map with
PCE Concentrations in Groundwater
October 2010
-------
EXHIBITA-5
Sanitary Sewer Lift
Station "Wet Well" o™"23
~ Sanitary Sewer Lift Station
Control Building
-W-24
City of Tumwater
^°^l Municipal Golf Course
Drainage
Ditch
Palermo
Neighborhood
n • \ t j v \ i
^ i—v \J
^ C^TJ
Drainag
Ditch
Capitol
5000 Bldg
Former Singer's
Gull Station
BARNES LAKE
Brewery
City Pizza
Chevron Station
Southgate
Dry Cleaners
Texaco Station
Southgate Mall
Trosper Road
Palermo
Valley Bluff
Poage's Towing
ay 1 Auto Repair
L'n
-------
EXHIBITA-6
364 - 2000' N @ DESCHUTES RIVER
361
111
AERATION LAGOON
CITY OF TUMWATER
MUNICIPAL
GOLF COURSE
ii n n — n n — n
tti if-:-!,1 M: :f-r!4
iii1 .1 . 'i i' i i.
PALERMO NEIGHBORHOOD
LIFT STATION
l (CONTROL BUILDING
'I IFSt^-li ih
~uu>3 iLdru..'L'iu //
TYPE 2 CATCH BASIN (TYP)
CAPITOL 5000
PROPERTY
FINGER DRAIN (TYP)
TRUNK DRAIN ALIGNMENT
SURFACE WATER CHANNEL
FLOWS TO NORTH
ITY OF TUMWATER
PALERMO WELLFIELD
Parametrix
DATE: 01/12/11 11:07am FILE: BR2328007P004TAN07 F1-2
LEGEND
SAMPLING STATION DESCRIPTIONS
100'
SCALE IN FEET
Piezometer Location
Water Sampling Station
Perforated Drainpipe
Tightline Drainpipe
350 M Street Storm Drain Outfall
356 Watercourse Upstream Of Lagoon
357 Cleanout CO6
358 Cleanout CO4
359 Cleanout CO1
360 Tightline Pipe Outfall
361 Lagoon Effluent
362 M Street Terminus CB Outfall (Rarely Flows)
Figure 1-2
Palermo Wellfield Superfund Site Subdrain System
and Treatment Lagoon Status Report
System Layout and Monitoring Stations
-------
ATTACHMENT B
-------
TCE Concentration ( ug/m3)
0 ,_, g
0 P !-> 0 0
l-i l-i l_i O O O
TCE Indoor and Crawl Space Air Sample Results and Risk Levels
^~*
* 5.6
4 4.6
• 3.6
431 431
* 2.7 • 2.6
• 2.2
* L8 ^ , c ^
^ -1"3 4 1.4 4 1.4 J
1 1-1 * 1-1 A no- II 1
0 MM > 0.98 V 1
u.81 u.e u.81 4^0.78
. A. n M O-1^ 4 u.bb
+ n " 4 0 " b 0 " bO" b 0 " U-:" • PS * 0.54 A 0 , k 0 - * Ui:" b 0 -
> U.J » U.J » U.J > U.J ^ Q 4g U.J4 o.4/ U'J ' U'J ' U'J
40.34* °'39 4 0.34 * °'39 ; *°'37
4 0.28 $ 8:2*7 * 0.28
0 21 . 0-19 0-22 0.22
i m » o.14 «§i§* ai8 »- :- »8:11 *o:»4013 ;:;: as
*o.ntol jo.ll t 01 i12 * "-11 i--- ""« *o.n * 0.115 °
4 0.085 ' U.(J9/^ o OXh Z OQ83 n nn * 0.087 ^ nnm
u.uoo » 007^* n n7? Ui(J" u.uai
L nn^a * OOf * 0nfiS
4^1.058 u.Ub
0 Or ^ 0 Or
•*• n n/n •*• n n/n 4 0.043 UlUJ A o 042 "'""" 4 0.043 4 0.044
Anm? [oof r°-038 0.03440.035 4 O.OSsf Pf5A n m,
w • 4 0.027 4 o:027
4 0 021
4 0.014 4 0.014 °-°
0 0105
) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
Sample results of Non-Detect (ND) are listed at half the reporting limit and marked in ORANGE House Number
Note: Several ND results represent multiple sample events, all ND with 1.0 Reporting Limit
Note: No detections above the 1.46 ug/m3 ROD cleanup goal have been seen since 2004. All detections exceeding 1.46 ug/m3 have been followed with at least one sample event with results below 1.46 ug/m3
WA DOE MTCA Method B value is 0.022 ug/m3; revised 0.098 ug/m3 value is under consideration
120 ug/m3
(IxlO-4)
QJ CO
c -c.
CT1 tC 60
C &. u
~ -w °
2r — "
£ ^ 9j
LLJ -t-* _
1/1 Q. tC
=> g >
U — 1
< 1/1
ROD Acceptable
x^ Risk Level
(1.46 ug/m3)
1.20 ug/m3
(IxlO-6)
)98 ug/m3
s
LLJ CO
O 73 -1
Q o -^
^=> — < -B a: ^
5 | « S
^ "^ -Q x
o
-------
ATTACHMENT C
-------
MW-109
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
•TCETrendline
-------
MW-111
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
-TCE Trendline
-------
MW-101B
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
•TCE Trendline
-------
MW-104B
PCE Concentration Time-Trend Plot
Sampling Date
•PCE
•PCETrendline
-------
MW-UI
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
-TCE Trendline
-------
MW-ES-02
TCE Concentration Time-Trend Plot
100
Sampling Date
-TCE
•TCE Trendline
-------
MW-ES-03
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
-TCE Trendline
-------
MW-ES-04
TCE Concentration Time-Trend Plot
2.5
O)
o
1.5
0)
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c
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LU 1
O
0.5
CD
D
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cr
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cp
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cr
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cr
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cr
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o
CD
03
^
03
Sampling Date
-TCE
-TCE Trendline
-------
MW-ES-04
PCE Concentration Time-Trend Plot
300
Sampling Date
•PCE
•PCETrendline
-------
MW-ES-05
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
-TCE Trendline
-------
MW-ES-06
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
-TCE Trendline
-------
MW-ES-06
PCE Concentration Time-Trend Plot
180
160
Sampling Date
•PCE
•PCETrendline
-------
MW-ES-07
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
•TCE Trendline
-------
MW-ES-09
TCE Concentration Time-Trend Plot
350
300
Sampling Date
-TCE
-TCETrendline
-------
MW-ES-10
TCE Concentration Time-Trend Plot
120
Sampling Date
-TCE
-TCETrendline
-------
PZ-721
TCE Concentration Time-Trend Plot
120
110
10
03
^
03
^^
CD
C
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CD
CD
03 C
i ^
03 O
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(35
oo
CD
Sampling Date
-TCE
•TCE Trendline
-------
PZ-721
PCE Concentration Time-Trend Plot
1.2
1.1
1
0.9
I0'7
| 0.6
o>
g 0.5
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uj 0.4
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Q.
0.3
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o
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CD
03
>5
O
CD
Sampling Date
•PCE
•PCE Trendline
-------
PZ-724
TCE Concentration Time-Trend Plot
03
•?
CD
CD
CD
CD
03
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O
CD
03
C5
03
C5
Sampling Date
-TCE
•TCE Trendline
-------
PZ-724
PCE Concentration Time-Trend Plot
1.2
^,0.8
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o
0.6
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o
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OO
o
3
Sampling Date
-PCE
•PCE Trendline
-------
PZ-728
TCE Concentration Time-Trend Plot
03
03
CD
CD
CD
CD
03
03
O
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03
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O
CD
03
03
03
03
Sampling Date
-TCE
•TCE Trendline
-------
TW-2
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
•TCE Trendline
-------
TW-4
TCE Concentration Time-Trend Plot
4.5
3 3.5
o>
c o
o
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5 25
^ 2.5
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03
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03
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cr
CD
03
^
C
03
Sampling Date
-TCE
•TCE Trendline
-------
TW-5
TCE Concentration Time-Trend Plot
Sampling Date
-TCE
•TCE Trendline
-------
ATTACHMENT D
-------
PCE, TCE and Flow at Station 350
Sampling Month
I PCE '
140
-------
PCE, TCE and Flow at Station 357
120
Sampling Month
IPCE ' 'T.F _*_Flow
-------
PCE, TCE and Flow at Station 358
Sampling Month
IPCE ' 'T.F _*_Flow
160
-------
PCE, TCE and Flow at Station 359
250
Sampling Month
IPCE '
-------
PCE, TCE and Flow at Station 360
300
-- 250
[I I '[I I '[I I '[I I '[I I '[
I I I I I I
200
Q.
O)
-- 150-a
n-- 100
-- 50
Sampling Month
IPCE ' 'T.F _*_Flow
-------
PCE, TCE and Flow at Station 361
1600
Sampling Month
IPCE ' 'T.F _*_Flow
-------
ATTACHMENT E
-------
-^N o
PVC Pipe
Surface water
t*'C Jt-tiLiltlW flSS fcltt«rW«-ll-J-.-ll
A
f.f.ilF |NF?='"
i ••^%-^.^.
H=?:;i.T-fB Cf^TlC"
^llTY ASSJV^ZL PflCL£CT P
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Figura ^-1
Palermo Wellfiald Suparfund Site
Second Five-Year Review
Subdrajn System and Treatment Lagoon
-------
ATTACHMENT F
-------
E
'•S.
O
PHOTO 1: Overview of Southgate Mall and Southgate Dry Cleaners,
looking west.
LAUNDROMAT DRY CLEANERS
PHOTO 2: Southgate Dry Cleaners lease space, looking northwest.
Page 1 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 3: Groundwater monitoring well and abandoned large diameter
feature located in the parking lot south of Southgate Dry Cleaners.
PHOTO 4: Looking east from Southgate Mall parking lot toward Capitol
Boulevard, with commercial businesses and the Palermo Valley Bluff
beyond.
Page 2 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 5: City of Tumwater Palermo Well Field - Dual air stripping towers
within and above pump house and water treatment building, looking
northeast.
PHOTO 6: City of Tumwater Palermo Well Field - Dual air stripping towers
within and above pump house and water treatment building, looking
southwest.
Page 3 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 7: City of Tumwater Palermo Well Field - Dual air stripping towers
within and above pump house and water treatment building, looking
southwest.
PHOTO 8: City of Tumwater Palermo Well Field - Dual air stripping towers
within and above pump house and water treatment building, looking east;
note seep drainage in foreground.
Page 4 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 9: City of Tumwater Palermo Well Field - Looking south toward
stake marking proposed TW-2 well replacement location, with TW-2 well
house in background.
PHOTO 10: City of Tumwater Palermo Well Field - Well house structures,
looking east-northeast.
Page 5 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 11: City of Tumwater Palermo Well Field - Looking northeast
toward well house structures (left) and undeveloped land beyond.
PHOTO 12: City of Tumwater Palermo Well Field - Interior of Pump House.
Page 6 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 13: City of Tumwater Palermo Well Field - Air Stripping Tower #2.
PHOTO 14: City of Tumwater Palermo Well Field - Chemical treatment
container (sodium hypochlorite) - typically not used - air strippers used instead
to adjust pH.
Page 7 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 15: City of Tumwater Palermo Well Field - Air ducting for Blower
No. 2 for Air Stripping Tower No. 2
PHOTO 16: Overview of residential neighborhood.
Page 8 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 17: Overview of residential neighborhood.
PHOTO 18: Overview of residential neighborhood.
Page 9 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 19: Overview of residential neighborhood.
PHOTO 20: Typical residential perimeter foundation with crawl space; note
crawl space ventilation.
Page 10 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 21: Close-up of residential foundation showing crawlspace
ventilation.
PHOTO 22: Seep drainage feature oriented west-east, south of House #6
at the southwest corner of the neighborhood, looking southeast.
Page 11 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 23: Seep drainage feature oriented west-east, south of House #6
at the southwest corner of the neighborhood, looking southwest.
PHOTO 24: Looking south from M Street, west of House #1 at the
northwest corner of the neighborhood, where seep drainage feature extends
to the south, behind (west of) homes along Rainier Avenue.
Page 12 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 25: Looking northwest at seep drainage south of neighborhood;
view toward backyard of homes along O Street; seep drainage is oriented
west-east.
PHOTO 26: Close-up of seep drainage south of O Street house, looking
north-northwest.
Page 13 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 27: View southwest along former Palermo Well Field access road,
southwest of well field, ascending bluff.
PHOTO 28: Apparent groundwater monitoring well and two bumper posts
along bluff.
Page 14 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 29: Debris, including tires and wheels, along bluff west of
residential neighborhood.
PHOTO 30: 8-inch diameter PVC pipe day-lighting along bluff west of
residential neighborhood; location estimated to be 60 feet west of the
northwest corner of House #4.
Page 15 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 31: Another view of 8-inch diameter drainage pipe along bluff.
PHOTO 32: Drain Pipe Treatment Lagoon northeast of neighborhood;
looking southeast, with golf course in background.
Page 16 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 33: Drain Pipe Treatment Lagoon, looking northeast, with golf
course in background.
PHOTO 34: Looking south toward up-stream end of Treatment Lagoon
drainage feature.
Page 17 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
E
'•S.
O
PHOTO 35: Looking northeast toward downstream end of Treatment
Lagoon drainage feature.
PHOTO 36: Looking east across Treatment Lagoon toward wells TW-20,
TW-23 and TW-24. "
Page 18 of 18
&EPA
PHOTOGRAPHIC LOG
Palermo Superfund Site
Tumwater, Washington
August 25, 2011
-------
ATTACHMENT G
-------
Palermo Area
5150 Capitol BlvdSE
Olympia, WA 98501
Inquiry Number: 3167828.1
September 16, 2011
DR Historical Topographic Map Report
EDR
Environmental Data Resources Inc
440 Wheelers Farms Road
Milford,CT 06461
800.352.0050
www.edrnet.com
-------
EDR Historical Topographic Map Report
Environmental Data Resources, Inc.s (EDR) Historical Topographic Map Report is designed to assist professionals in
evaluating potential liability on a target property resulting from past activities. EDRs Historical Topographic Map Report
includes a search of a collection of public and private color historical topographic maps, dating back to the early 1900s.
Thank you for your business.
Please contact EDR at 1-800-352-0050
with any questions or comments.
Disclaimer - Copyright and Trademark Notice
This Report contains certain information obtained from a variety of public and other sources reasonably available to Environmental Data Resources, Inc.
It cannot be concluded from this Report that coverage information for the target and surrounding properties does not exist from other sources. NO
WARRANTY EXPRESSED OR IMPLIED, IS MADE WHATSOEVER IN CONNECTION WITH THIS REPORT. ENVIRONMENTAL DATA
RESOURCES, INC. SPECIFICALLY DISCLAIMS THE MAKING OF ANY SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION,
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE OR PURPOSE. ALL RISK IS ASSUMED BY THE USER. IN NO EVENT SHALL
ENVIRONMENTAL DATA RESOURCES, INC. BE LIABLE TO ANYONE, WHETHER ARISING OUT OF ERRORS OR OMISSIONS, NEGLIGENCE,
ACCIDENT OR ANY OTHER CAUSE, FOR ANY LOSS OF DAMAGE, INCLUDING, WITHOUT LIMITATION, SPECIAL, INCIDENTAL,
CONSEQUENTIAL, OR EXEMPLARY DAMAGES. ANY LIABILITY ON THE PART OF ENVIRONMENTAL DATA RESOURCES, INC. IS STRICTLY
LIMITED TO A REFUND OF THE AMOUNT PAID FOR THIS REPORT. Purchaser accepts this Report AS IS. Any analyses, estimates, ratings,
environmental risk levels or risk codes provided in this Report are provided for illustrative purposes only, and are not intended to provide, nor should they
be interpreted as providing any facts regarding, or prediction or forecast of, any environmental risk for any property. Only a Phase I Environmental Site
Assessment performed by an environmental professional can provide information regarding the environmental risk for any property. Additionally, the
information provided in this Report is not to be construed as legal advice.
Copyright 2011 by Environmental Data Resources, Inc. All rights reserved. Reproduction in any media or format, in whole or in part, of any report or map
of Environmental Data Resources, Inc., or its affiliates, is prohibited without prior written permission.
EDR and its logos (including Sanborn and Sanborn Map) are trademarks of Environmental Data Resources, Inc. or its affiliates. All other trademarks
used herein are the property of their respective owners.
-------
Historical Topographic Map
IN
T
TARGET QUAD
NAME: OLYMPIA
MAP YEAR: 1937
SERIES:
SCALE:
15
1:62500
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
;•••/ • ..-'OLYMPlAv '•'.
N
T
TARGET QUAD
NAME: OLYMPIA
MAP YEAR: 1949
SERIES: 15
SCALE: 1:62500
SITE NAME: Palermo Area
ADDRESS: 51 50 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 / -122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
" A
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—,-*' " •*•»->—\'*—>\ T \-^\\ • "i
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IN
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TARGET QUAD
NAME: OLYMPIA
MAP YEAR: 1949
SERIES:
SCALE:
7.5
1:25000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1959
SERIES:
SCALE:
7.5
1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
~~= . ^<"if I? '.....:'.'-" ~I wa
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*;. : ^-'"^e...
N
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1968
PHOTOREVISED:1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 51 50 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 / -122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
5Q6 55' fVl IK CLNTRALIA 20 Ml
IN
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1973
PHOTOREVISED:1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
TARGET QUAD
NAME: OLYMPIA
MAP YEAR: 1974
SERIES:
SCALE:
15
1:50000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
5Q6 55' "I / Ct£N1RALIA V4 *»/
IN
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1981
PHOTOREVISED:1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1994
REVISED: 1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
rwe
IN
T
TARGET QUAD
NAME: TUMWATER
MAP YEAR: 1997
SERIES:
SCALE:
7.5
1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
ADJOINING QUAD
NAME: CHEHALIS
MAP YEAR: 1916
SERIES: 30
SCALE: 1:125000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
T vmS
IN
T
ADJOINING QUAD
NAME: TENINO
MAP YEAR: 1944
SERIES:
SCALE:
15
1:62500
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
ADJOINING QUAD
NAME: MAYTOWN
MAP YEAR: 1949
SERIES:
SCALE:
7.5
1:25000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
/H /I
- y>
_s£—H -« /C
IN
T
ADJOINING QUAD
NAME: TENINO
MAP YEAR: 1949
SERIES:
SCALE:
15
1:62500
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
ADJOINING QUAD
NAME: MAYTOWN
MAP YEAR: 1959
SERIES:
SCALE:
7.5
1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
i OL > MPIAI *11
IN
T
ADJOINING QUAD
NAME: TENINO
MAP YEAR: 1959
SERIES:
SCALE:
15
1:62500
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
IN
T
ADJOINING QUAD
NAME: MAYTOWN
MAP YEAR: 1968
PHOTOREVISED:1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
'^' 1 SF^OL\-n
-• 3*jc:Mffi/j/
IN
T
ADJOINING QUAD
NAME: MAYTOWN
MAP YEAR: 1973
PHOTOREVISED:1959
SERIES: 7.5
SCALE: 1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
JM/ CK-tV ^s *- — ' -f' f- ^ /[
• ,/fl ^^.
IN
T
ADJOINING QUAD
NAME: TENINO
MAP YEAR: 1975
SERIES:
SCALE:
15
1:50000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Historical Topographic Map
= =• '•:•: I--*1.1
'in
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LlllkJ
CAS£_3QAD EXTENSION
IN
T
ADJOINING QUAD
NAME: MAYTOWN
MAP YEAR: 1990
SERIES:
SCALE:
7.5
1:24000
SITE NAME: Palermo Area
ADDRESS: 5150 Capitol Blvd SE
Olympia, WA 98501
LAT/LONG: 47.0012 /-122.9093
CLIENT: Tetra Tech GEO
CONTACT: Keith Hoofard
INQUIRY*: 3167828.1
RESEARCH DATE: 09/16/2011
-------
Palermo Area
5150 Capitol BlvdSE
Olympia, WA 98501
Inquiry Number: 3164761.1
September 13, 2011
he EDR Aerial Photo Decade Packag
EDR
Environmental Data Resources Inc
440 Wheelers Farms Road
Milford,CT 06461
800.352.0050
www.edrnet.com
-------
EDR Aerial Photo Decade Package
Environmental Data Resources, Inc. (EDR) Aerial Photo Decade Package is a screening tool designed to assist
environmental professionals in evaluating potential liability on a target property resulting from past activities. EDR's
professional researchers provide digitally reproduced historical aerial photographs, and when available, provide one photo
per decade.
When delivered electronically by EDR, the aerial photo images included with this report are for ONE TIME USE
ONLY. Further reproduction of these aerial photo images is prohibited without permission from EDR. For more
information contact your EDR Account Executive.
Thank you for your business.
Please contact EDR at 1-800-352-0050
with any questions or comments.
Disclaimer - Copyright and Trademark Notice
This Report contains certain information obtained from a variety of public and other sources reasonably available to Environmental Data Resources, Inc.
It cannot be concluded from this Report that coverage information for the target and surrounding properties does not exist from other sources. NO
WARRANTY EXPRESSED OR IMPLIED, IS MADE WHATSOEVER IN CONNECTION WITH THIS REPORT. ENVIRONMENTAL DATA
RESOURCES, INC. SPECIFICALLY DISCLAIMS THE MAKING OF ANY SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION,
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE OR PURPOSE. ALL RISK IS ASSUMED BY THE USER. IN NO EVENT SHALL
ENVIRONMENTAL DATA RESOURCES, INC. BE LIABLE TO ANYONE, WHETHER ARISING OUT OF ERRORS OR OMISSIONS, NEGLIGENCE,
ACCIDENT OR ANY OTHER CAUSE, FOR ANY LOSS OF DAMAGE, INCLUDING, WITHOUT LIMITATION, SPECIAL, INCIDENTAL,
CONSEQUENTIAL, OR EXEMPLARY DAMAGES. ANY LIABILITY ON THE PART OF ENVIRONMENTAL DATA RESOURCES, INC. IS STRICTLY
LIMITED TO A REFUND OF THE AMOUNT PAID FOR THIS REPORT. Purchaser accepts this Report AS IS. Any analyses, estimates, ratings,
environmental risk levels or risk codes provided in this Report are provided for illustrative purposes only, and are not intended to provide, nor should they
be interpreted as providing any facts regarding, or prediction or forecast of, any environmental risk for any property. Only a Phase I Environmental Site
Assessment performed by an environmental professional can provide information regarding the environmental risk for any property. Additionally, the
information provided in this Report is not to be construed as legal advice.
Copyright 2011 by Environmental Data Resources, Inc. All rights reserved. Reproduction in any media or format, in whole or in part, of any report or map
of Environmental Data Resources, Inc., or its affiliates, is prohibited without prior written permission.
EDR and its logos (including Sanborn and Sanborn Map) are trademarks of Environmental Data Resources, Inc. or its affiliates. All other trademarks
used herein are the property of their respective owners.
-------
Date EDR Searched Historical Sources:
Aerial Photography September 13, 2011
Target Property:
5150 Capitol BlvdSE
Olympia, WA 98501
Year Scale
1941 Aerial Photograph. Scale: 1"=750'
Details Source
Panel #: 47122-A8, Tumwater, WA;/Flight Date: July 10, 1941 EDR
1957 Aerial Photograph. Scale: 1"=750'
Panel #: 47122-A8, Tumwater, WA;/Flight Date: July 18, 1957 EDR
1969 Aerial Photograph. Scale: 1"=750'
Panel #: 47122-A8, Tumwater, WA;/Flight Date: March 10, 1969 EDR
1973 Aerial Photograph. Scale: 1"=500'
Panel #: 47122-A8, Tumwater, WA;/Flight Date: May 28, 1973 EDR
1975 Aerial Photograph. Scale: 1"=1000'
1980 Aerial Photograph. Scale: 1"=1000'
Panel #: 47122-A8, Tumwater, WA;/Flight Date: September 13, EDR
1975
Panel #: 47122-A8, Tumwater, WA;/Flight Date: July 29, 1980 EDR
1982 Aerial Photograph. Scale: 1"=1000'
Panel #: 47122-A8, Tumwater, WA;/Flight Date: August 06, 1982 EDR
1990 Aerial Photograph. Scale: 1"=604'
2005 Aerial Photograph. Scale: 1"=604'
Panel #: 47122-A8, Tumwater, WA;/Composite DOQQ -
acquisition dates: June 21, 1990
Panel #: 47122-A8, Tumwater, WA;/Flight Year: 2005
EDR
EDR
2006 Aerial Photograph. Scale: 1"=604'
Panel #: 47122-A8, Tumwater, WA;/Flight Year: 2006
EDR
3164761.1
2
-------
INQUIRY*: 3164761.1
YEAR: 1941
I
N
H = 750'
-------
• '**• ""fr. '**-Sr ••£** * 2r ' •• rr " •»' 1 »
LSgfW k*
^|»
r Jl dife-^.
r T^""1i» . ^-^
•:- ;
"^ '
INQUIRY*: 3164761.1
'f^SIP:
-------
INQUIRY*: 3164761.1
-------
T
• _ • ^'
* ^
<*;
INQUIRY*: 3164761.1
-------
INQUIRY*: 3164761.1
YEAR: 1975
I 1 = 1000'
-------
INQUIRY*: 3164761.1
-------
INQUIRY*: 3164761.1
YEAR: 1982
I 1 = 1000'
N
-------
INQUIRY*: 3164761.1
-------
m
r
INQUIRY*: 3164761.1
YEAR: 2005
I
H = 604'
-------
INQUIRY*: 3164761.1
-------
WEST
FORMER
WSDOT
MIL
200
WSDOT
MIL
(NORTH OF
SECTION)
POSSIBLE
VAPOR
INTRUSION
SOUTHGATE
SHOPPING
CENTER
Q
CO
EAST
— 200
150 —
CO
oo
Q
O
O
I
LU
111
100 —
PALERMO
BLUFF
POSSIBLE
CONTINUING
PCE SOURCE
CONTINUING
TCESOURCE
GROUNDWATER
SEEPS
TCE
PLUME
POSSIBLE
VAPOR
INTRUSION
VASHON
RECESSIONAL
OUTWASH
PALERMO
NEIGHBORHOOD
PCE
PLUME
PALERMO
WELLFIELD
TCE PLUME
MAY
EXTEND
EASTWARD
VASHON
TILL
i i i
TERTIARY
BEDROCK
KITSAP
FORMATION
50
oo
oo
Q
O
O
1
LU
111
0
NOTE: ELEVATIONS ARE APPROXIMATE. NOT TO SCALE.
-50
FIGURE 1
CROSS SECTION ILLUSTRATION OF SITE CONCEPTUAL MODEL
Palermo Wellfield Superfund Site
------- |