PROPOSED REMEDIAL ACTION PLAN ADDENDUM5 3.0 REMEDIAL INVESTIGATION RESULTS Remedial investigation...

HARGIS + ASSOCIATES, INC. HYDROGEOLOGY ENGINEERING

JANUARY 31, 2020

PROPOSED REMEDIAL ACTION PLAN

ADDENDUM

7TH STREET AND ARIZONA AVENUE

847 NORTH STONE PROPERTY

WATER QUALITY ASSURANCE REVOLVING FUND SITE

HARGIS + ASSOCIATES, INC.

1195.01_H01_PRAP Addendum_Txt 1/22/2020

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PROPOSED REMEDIAL ACTION PLAN ADDENDUM

7th STREET AND ARIZONA AVENUE 847 NORTH STONE PROPERTY


TABLE OF CONTENTS Section Page ACRONYMS AND ABBREVIATIONS .......................................................................................... iv

1.0 INTRODUCTION .......................................................................................................................... 1 1.1 7TH STREET & ARIZONA AVENUE WQARF SITE ............................................................. 2 1.2 THE STONE AVENUE SITE ................................................................................................... 3

2.0 STONE AVENUE SITE BOUNDARIES ...................................................................................... 4 3.0 REMEDIAL INVESTIGATION RESULTS .................................................................................... 5

3.1 EARLY RESPONSE ACTIONS .............................................................................................. 7 3.2 SOURCE OF CONTAMINATION ........................................................................................... 8 3.3 CONSTITUENTS OF CONCERN........................................................................................... 8 3.4 NATURE AND EXTENT OF CONTAMINATION ................................................................... 8

3.4.1 Vadose Zone ................................................................................................................... 9 3.4.2 Groundwater .................................................................................................................... 9

3.5 REMEDIAL OBJECTIVES .................................................................................................... 10 4.0 FEASIBILITY STUDY RESULTS............................................................................................... 12

4.1 IDENTIFICATION AND SSCREENING OF REMEDIAL TECHNOLOGIES ....................... 12 4.2 EVALUATION AND COMPARISON OF THE REMEDIES .................................................. 12 4.3 PROPOSED REMEDY ......................................................................................................... 13

5.0 PROPOSED REMEDY AND ESTIMATED OST ....................................................................... 15 5.1 REMEDY DESCRIPTION ..................................................................................................... 15

5.1.1 Proposed Remedy – Vadose Zone ............................................................................... 15 5.1.2 Proposed Remedy – Groundwater ............................................................................... 17

5.2 PERFORMANCE MONITORING AND PERIODIC REVIEWS ............................................ 18 5.3 ESTIMATED COST ............................................................................................................... 18 5.4 DURATION ............................................................................................................................ 18 5.5 CONTINGENCIES ................................................................................................................ 18

5.5.1 Additional Soil Vapor Extraction Time ........................................................................... 19 5.5.2 Additional Soil Vapor Extraction Wells .......................................................................... 19 5.5.3 Additional Regional Groundwater Monitor Wells .......................................................... 19 5.5.4 Additional Perched Groundwater Monitor Wells ........................................................... 19 5.5.5 Regional Aquifer Remediation ...................................................................................... 20

6.0 CONSIDERATION OF REMEDIATION GOALS AND SELECTION FACTORS ..................... 21 6.1 RATIONALE FOR SELECTION OF THE REMEDY ............................................................ 21


TABLE OF CONTENTS (continued) Section Page


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6.2 ACHIEVEMENT OF REMEDIAL OBJECTIVES .................................................................. 22 6.3 ACHIEVEMENT OF REMEDIAL ACTION CRITERIA ......................................................... 22 6.4 CONSISTENCY WITH WATER MANAGEMENT PLANS ................................................... 23 6.5 CONSISTENCY WITH GENERAL LAND USE PLANNING ................................................ 23 6.6 LEAD AGENCY STATEMENT FOR PROPOSED REMEDY .............................................. 23 6.7 PUBLIC COMMENT PERIOD .............................................................................................. 23

7.0 REFERENCES ........................................................................................................................... 24


TABLE OF CONTENTS (continued)


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TABLES Table 1 TETRACHLOROETHENE IN SOIL VAPOR, PRE-ADEQ INVESTIGATIONS 2 SUMMARY OF TETRACHLOROETHENE IN SOIL 3 SUMMARY OF TETRACHLOROETHENE IN SOIL VAPOR, ADEQ

INVESTIGATIONS 4 SUMMARY OF REMEDIAL ALTERNATIVES AS PRESENTED IN FS (IN-TEXT

TABLE, PAGE 15)

FIGURES Figure 1 SITE LOCATION

2 SITE PLAN

3 MAXIMUM CONCENTRATION OF TETRACHLOROETHENE IN SOIL VAPOR

4 CONCENTRATION OF TETRACHLOROETHENE IN SOIL VAPOR - MAY 2019

5 CROSS SECTION A – A’

6 TETRACHLOROETHENE IN GROUNDWATER – PERCHED AQUIFER

7 CROSS SECTION B – B’

8 SVE SYSTEM LAYOUT PLAN

APPENDICES Appendix A DETAILED COST INFORMATION FOR THE REMEDIAL ALTERNATIVE



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ACRONYMS AND ABBREVIATIONS

ADEQ Arizona Department of Environment Quality AS air sparging AWQS Arizona Water Quality Standards bls below land surface cis-1,2-DCE cis-1,2-dichloroethene COCs constituents of concern EPA U.S. Environmental Protection Agency ERA Early Response Action ESA Environmental Site Assessment FS feasibility study GPL groundwater protection leaching H+A Hargis + Associates, Inc. HGC Hydro Geo Chem, Inc. LNAPL light non-aqueous phase liquid MCL maximum contaminant level mg/kg milligrams per kilogram mg/L milligram per liter PCE tetrachloroethene PRAP proposed remedial action plan RI remedial investigation RO remedial objective RSLs regional screening levels SRLs soil remediation levels SVE soil vapor extraction SVSLs soil vapor screening levels TCE trichloroethene Terracon Terracon Consultants, Inc. trans-1,2-DCE trans-1,2-dichloroethene μg/L micrograms per liter μg/m3 micrograms per cubic meter VGAC vapor-phase granular activated carbon VOC volatile organic compounds WQARF Water Quality Assurance Revolving Fund



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PROPOSED REMEDIAL ACTION PLAN ADDENDUM

7th STREET AND ARIZONA AVENUE 847 NORTH STONE PROPERTY


1.0 INTRODUCTION

This Proposed Remedial Action Plan Addendum (PRAP-Addendum) presents the preferred

remedial action alternative for addressing chlorinated solvent contamination in the soil and

groundwater beneath and adjacent to 847 N. Stone Avenue, Tucson, Arizona (Stone Avenue

Site). The Stone Avenue Site is a secondary source of contamination located within the 7th Street

and Arizona Avenue Water Quality Assurance Revolving Fund (WQARF) Site in Tucson, Arizona

(Figure 1). In 2014, a Proposed Remedial Action Plan (PRAP) was completed for the 7th Street

& Arizona Avenue Site (Hydro Geo Chem, Inc. [HGC], 2014c) before the Stone Avenue Site was

identified as a potential source. The proposed remedy documented in the 2014 PRAP included

soil vapor extraction (SVE) with air sparging (AS) and long-term monitoring of groundwater (HGC,

2014c). This PRAP-Addendum has been prepared to amend the existing PRAP to address

contamination at the Stone Avenue Site. This work is being conducted for Arizona Department of

Environmental Quality (ADEQ) under ADEQ Purchase Order number PO0000147385.

This PRAP-Addendum considers data and findings from Stone Avenue Site investigations and

Early Response Action (ERA) as well as investigations performed for the 7th Street & Arizona

Avenue Site. It was prepared in accordance with A.A.C. R18-16-408 and A.R.S. §49-287.04(A).

This PRAP-Addendum contains the following:

1. A description of the proposed remedy. 2. The information required in A.R.S. § 49-287.04(A).

o The boundaries of the site or portion of the site that is the subject of the remedial action.

o The results of the remedial investigation (RI) and feasibility study (FS). o The proposed remedy and its estimated costs. o Consideration of the remediation goals and selection factors in A.R.S. §49-282.06.



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3. A description of how the proposed remedy will achieve each of the remedial objectives (ROs) identified in the final remedial investigation report under R18-16-406(J) and how accomplishment of the ROs is to be measured.

4. A description of all recharge, reinjection, discharge, transportation and use of remediated water as defined in A.R.S. § 49-283.01.

This PRAP-Addendum outlines the proposed remedy capable of achieving the ROs, which

include restoring soil conditions to meet non-residential and or residential standards as

appropriate and protecting the regional aquifer from contamination. ADEQ will select the remedy

for the Site, proposed in the PRAP and PRAP-Addendum, which will be documented in a Record

of Decision (ROD).

1.1 7TH STREET & ARIZONA AVENUE WQARF SITE

The 7th Street & Arizona Avenue WQARF Site addresses contamination originating from the

former Oliver’s Laundry and Dry Cleaning Company (Oliver’s Cleaners). Oliver’s Cleaners

operated a dry cleaning facility at 300 East 7th Street in Tucson, Arizona from at least 1957 until

the facility burned down in 1989 (HGC, 2014a). Based on information obtained during multiple

subsurface investigations performed at the Site, the dry cleaning solvent tetrachloroethene (PCE)

was released to the subsurface, contaminating the soil and perched groundwater. Environmental

investigations, starting in the 1990’s, identified elevated concentrations of volatile organic

compounds (VOC), especially PCE in the soil and perched groundwater. Concentrations of PCE,

above the Arizona Water Quality Standard (AWQS) of 5 micrograms per liter (μg/L), have been

detected in the perched groundwater beneath and down-gradient of former Oliver’s Cleaners

forming a PCE plume. The 7th Street & Arizona Avenue Site boundary is based on the extent of

the PCE plume, which extends approximately 4,500 feet northwest of the former Oliver’s Cleaners

property (Figure 1). The 7th Street & Arizona Avenue Site was placed on the WQARF registry on

April 27, 2000. Twenty groundwater monitor wells (7AZP-1 to 7AZP-20) have been constructed

to delineate the extent of VOCs in the perched groundwater. The most recent of these, 7AZP-20,

was completed in December 2016 (H+A, 2017). Monitor wells installed to investigate other sites

(Yellow Cab, Union Pacific Railroad Passenger Depot, Bridgestone/Firestone Service Center)

have also been utilized to delineate the extent of VOCs in the perched groundwater. Additionally,

5 monitor wells (7AZR-1 to 7AZR-5) have been installed to monitor and determine any impacts to

the regional aquifer.



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1.2 THE STONE AVENUE SITE

The Stone Avenue Site addresses contamination originating from a former dry cleaning facility,

which operated from 1996 to 2001 at 847 North Stone Avenue. The 0.4-acre property at 847 N.

Stone Avenue currently includes a warehouse of approximately 9,600 square foot; the warehouse

is currently used for storage of miscellaneous goods and is not occupied on any kind of continual

basis.

The site is bordered on the north by 2nd Street, on the east by Stone Avenue, to the south by a

student apartment complex, and on the west by parking for the apartment complex. More student

apartments are present 100 feet away on the north side of 2nd Street, and a residential

neighborhood borders the apartment parking, ~100 feet to the west of the site.

The parcel was used at various times from the mid-1940’s to the late 1960’s as an automobile

dealership, garage, service station, and an RV repair facility. At some point during this period,

seven hydraulic lifts were installed; these lifts remain in place today. Following this period, the

building was a dry cleaning facility from 1996 to 2001. The owner of the dry cleaning business

stated in 2012 that one of the cleaning machines had had a leak, and that the machines were

located in the southwestern corner of the building. (Terracon, 2013). Most recently, the property

was occupied by Granite Plus, Inc., a stone countertop manufacturer; however, since May 2016

the property has remained vacated and used for storage.

The City of Tucson began performing environmental investigations of the Stone Avenue Site in

2013 where investigations showed PCE contamination was present from the surface to perched

groundwater. ADEQ incorporated the Stone Avenue Site into the 7th Street & Arizona Avenue

WQARF Site in 2015 due to its location within the WQARF Site boundary. In 2016, a single

perched groundwater monitor well (7AZP-19) was constructed within the warehouse on the

property. Additionally, several soil vapor probes were installed on the property and adjacent

properties. Elevated concentrations of PCE were detected in the soil, soil vapor and groundwater.

In 2017, ADEQ initiated an ERA, which included installation and operation of a SVE system to

remediate elevated levels of PCE detected in the soil vapor.



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2.0 STONE AVENUE SITE BOUNDARIES Pursuant to A.R.S. §49-287.04(A)(1), this section presents a description of the boundaries of the

Site subject to remedial action. The Stone Avenue Site is located at 847 N. Stone Avenue,

Tucson, Arizona. The boundaries of the site subject to remediation include:

the subject and adjacent residential or commercial properties where elevated concentrations of PCE in soil vapor pose a vapor intrusion risk;

PCE-contaminated soils beneath the property that pose a threat to the groundwater;

PCE-contaminated soils beneath the property with concentrations of PCE greater than Arizona Soil Remediation Levels (SRLs); and

the extent of the groundwater with PCE concentrations exceeding the AWQS of 5 μg/L (Figure 1).

The adjacent properties include commercial and residential land uses. The groundwater plume

underlies an area that is a mix of industrial, commercial, and residential land uses.



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3.0 REMEDIAL INVESTIGATION RESULTS

Remedial investigation results for the Stone Avenue Site are based on information obtained

during multiple subsurface investigations performed at the Site and within the 7th Street & Arizona

Avenue WQARF site. Therefore, this section of the PRAP-Addendum will describe the results of

remedial investigation activities conducted at the Stone Avenue Site.

In 1999, a limited soil-sampling program was performed by Western Technologies, Incorporated

which included collection of soil and soil vapor samples (Terracon, 2013). Six soil gas samples

were collected and analyzed for VOCs. PCE in soil vapor ranged from 91 to 56,000 μg/L at depths

of 2.5 to 4 feet below land surface (bls) (Table 1). Three soil borings (SB-1, SB-2 and SB-3) were

drilled to a maximum depth of 55 feet bls. PCE was detected in soil at concentrations ranging

from 0.1 to 5.1 milligrams per kilogram (mg/kg) (Table 2), below the 1997 residential SRL of 53

mg/kg. The maximum depth PCE was detected in soil was at 55 feet bls at a concentration of 1.6

mg/kg (Table 2). Groundwater was not sampled. It was concluded that a release of contaminants

had occurred within the vicinity of the three dry cleaning machines.

In 2013, a Phase I Environmental Site Assessment (ESA) of the site was performed by the City

of Tucson (Terracon, 2013). The report provided descriptions of prior operations, records

reviews, and previous environmental investigations (Terracon, 2013). The report recommended

assessing potential impacts from the former automobile lifts and former drycleaner operation.

In 2013, as recommended in the Phase I ESA, a limited site investigation was also performed by

the City of Tucson, which included:

advancing five soil borings (HL-1, HL-2, HL-3, HL-4 and GW-5) from which 11 soil samples and a single grab groundwater sample were collected (Figure 2);

soil and groundwater samples were analyzed for VOCs, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and Resource Conservation and Recovery Act metals. In addition, the groundwater sample was analyzed for pH; and

collection and analysis of four sub-slab soil vapor samples (V-6, V-7, V-8 and V-9).



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PCE was detected in soil samples from all five borings and up to 1,800 mg/kg at 7.5 feet bls in

HL-1, located between the second and third hydraulic lifts from the east end of the building (Table

2). This vastly exceeded the residential and non-residential SRL for PCE issued in 2007 (0.51

mg/kg and 13 mg/kg, respectively). PCE in soil vapor was detected at all four sub-slab locations

at concentrations ranging from 350,000 micrograms per cubic meter (μg/m3) at location V-9 (east

of the southwest corner) to 1,700,000 μg/m3 at location V-8 (north of the southwest corner). PCE

was detected in groundwater at a concentration of 1,600 μg/L in boring GW-5 (in the southwest

corner). This result is well above the Aquifer Water Quality Standard (AWQS) of 5 μg/L. Arsenic

was also detected in groundwater samples from GW-5 at concentrations of up to 0.034 milligrams

per liter (mg/L), which is above the AWQS of 0.010 mg/L. The report concluded:

Based on the soil sampling results, the use as an RV repair facility and former hydraulic lifts does not appear to have adversely impacted the site.

Based on the soil and soil vapor results, the former use as a dry cleaner has impacted the site. The detected concentrations of PCE in soil, groundwater and soil vapor are above the ADEQ Non-residential SRL, AWQS and EPA Regional Screening Levels (RSL), respectively.

The grab groundwater samples contained concentrations of PCE that exceed the ADEQ AWQS (Terracon, 2014).

In 2016, additional environmental investigations were performed by ADEQ at the property,

including:

installation of: o one (1) nested monitor well (7AZP-19) (Figure 2), o ten (10) temporary soil vapor probes, and o four (4) permanent soil vapor probes;

collection of three soil samples from 7AZP-19 at 25, 30 and 40 feet bls for VOC analysis;

collection of 14 soil vapor samples from 5 feet bls for VOC analysis;

collection of a soil vapor sample from 7AZP-19 at 15, 40, 60, and 72 feet bls for VOC analysis;

collection of a groundwater sample from the completed well (7AZP-19) and analysis for VOC and metals (H+A, 2016).



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PCE was the only VOC detected in the soil samples (Table 2). PCE was detected in all three soil

samples collected at concentrations ranging from 0.15 mg/kg to 1.70 mg/kg. PCE was detected

in all soil vapor samples collected, at concentrations ranging from 140,000 μg/m3 to 7,500,000

μg/m3 (Table 3). PCE concentrations were highest in soil vapor probes at the southern end of the

property; this included TVP-7 (1,100,000 μg/m3) and TVP-8 (1,900,000 μg/m3), SVP-4 (4,400,000

μg/m3), and 7AZP-19 (6,400,000 to 7,500,000 μg/m3, as deep as 72 ft bls). These southern vapor

points were all within 50 feet of the student apartments to the south; TVP-7 and TVP-8 were 20

feet from the edge of the apartment building, raising concerns about vapor intrusion in the

apartment units. Trichloroethene (TCE) was also detected in four of the collected soil vapor

samples, at concentrations ranging from 150 μg/m3 to 6,300 μg/m3. No other VOC were detected

in soil vapor samples. PCE was detected in groundwater at a concentration of 1,000 μg/L (above

the AWQS of 5 μg/L). Cis-1,2-dichloroethene (cis-1,2-DCE) and TCE, were detected at 1.3 μg/L

and 4.1 μg/L, both below their respective AWQS of 7 and 5 µg/L. Both arsenic and selenium were

also detected, though well below Residential Soil Remediation Levels (H+A, 2016). Based on the

soil vapor results, especially near the student apartments, ADEQ determined that an ERA was

appropriate for reducing PCE concentrations in soil vapor.

3.1 EARLY RESPONSE ACTIONS

ADEQ initiated an ERA at the Stone Avenue Site because of the high levels of PCE in soil vapor.

The ERA included installing and operating a SVE system with the purpose to remediate source

area PCE soil impacts at the Property, which were believed to have contributed to groundwater

contamination at the Site. Additionally, it was hoped that the SVE system would minimize or

mitigate the migration of impacted soil vapor off the Property, and towards proximal apartment

building to the south of the Property, residential homes to the west, or to the residential building

located across 2nd Street to the north (Figure 2) (URS, 2017).

The SVE system consisted of four borings (SVE-1 through -4). Each boring was triple-nested,

with shallow (6-16 or 6-21 ft bls), medium (26-36 ft bls) and deep (41-86 ft bls) screened sections,

yielding twelve vapor wells. All twelve vapor wells were connected via underground horizontal

PVC piping to a manifold where flow from each well could be controlled. Soil vapor was extracted

from the wells using a rotary-lobe blower powered by a 7.5 horsepower motor to create a vacuum



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in the soil vapor wells. After moisture was extracted, the soil vapor passed through a pair of

vessels connected in series. These vessels each contained 2000 pounds of granulated activated

carbon derived from coconut husks. This activated carbon captured volatile organic compounds

from the soil vapor stream before discharging the vapor to the atmosphere.

The SVE system operated from December 2017 to April 2019 and removed an estimated mass

of approximately 1,553 pounds of VOCs. The system was shut down due to decreasing PCE

mass removal rates in April 2019. A rebound-testing program is currently ongoing; and initial

sampling results indicate significant soil vapor rebound has occurred (HGC, 2019).

A sub-slab ventilation system was constructed by the property owner in 2017 at the apartment

complex south of 847 N. Stone Avenue. Detailed information of sub-slab system has not been

provided by the property owner to ADEQ. However, initial results from the soil vapor rebound

study indicate that the sub-slab ventilation system is drawing PCE-contaminated soil vapor

towards the southern apartment complex in the absence of compete vapor extraction on the Stone

Source Site.

3.2 SOURCE OF CONTAMINATION

Environmental investigations performed at the property indicate that the chlorinated solvent PCE

was released to the subsurface impacting the soil, soil vapor, and perched groundwater. PCE

was commonly used in the dry cleaning industry. The dry cleaner operator stated that one of the

three dry cleaning machines leaked (Terracon, 2013). Therefore, the release of PCE is likely

attributed to historical releases from the dry cleaning operations conducted from 1996 to 2001.

3.3 CONSTITUENTS OF CONCERN

The constituents of concern (COCs) for the 7th Street & Arizona Avenue WQARF Site are PCE

and the breakdown products TCE, cis-1,2-DCE and trans-1,2-dichloroethene (trans-1,2-DCE)

(HGC, 2014c). At the Stone Avenue Site, PCE is the only COC found above AWQS and SRL.

3.4 NATURE AND EXTENT OF CONTAMINATION



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3.4.1 Vadose Zone

Both the soil and soil vapor beneath the Stone Avenue Site have been impacted with PCE. The

impacts are from the surface to the perched groundwater encountered at approximately 85 feet

bls (H+A, 2019).

Soil sampling has been performed primarily in the southwest corner of the building, where the dry

cleaning machines were located. PCE at concentrations above non-residential SRLs of 13 mg/kg

were detected at boring HL-1 (1,800 mg/kg at 7.5 feet and 440 mg/kg at 10 feet bls) (Table 2).

Exceedances of the PCE residential SRL of 0.51 mg/kg was detected at borings HL-1, GW-5 and

monitor well 7AZP-19 (Table 2).

Soil vapor sampling has been performed across the Stone Avenue Site and adjacent properties

(Figures 2 and 3). For the purpose of establishing site soil vapor screening levels (SVSLs) the

U.S. Environmental Protection Agency (EPA) RSL (EPA, 2019) for residential and industrial

indoor air were divided by an attenuation factor of 0.03. The calculated residential and industrial

screening levels (SVSL-residential and SVSL-industrial, respectively) for PCE are 367 μg/m3 and

1,567 μg/m3, respectively. Prior to operation of the SVE system soil vapor concentrations

exceeded SVSL-industrial at all sample locations on the Stone Avenue Site and adjacent

properties with the exception of 2 locations (SA-TVP-11 & SA-TVP-12) on North 9th Street (Figure

3). The ERA SVE system operated from December 2017 to April 2019 and reduced PCE in soil

vapor an average of 95% (see Table 3). However, concentrations exceeding SVSL-industrial were

still present on the property after SVE and concentrations exceeding SVSL-residential were

detected at the apartments located to the south (Figure 4 and 5).

3.4.2 Groundwater

Figure 6 presents the current estimated extent of PCE in perched groundwater exceeding the

AWQS of 5 μg/L. Perched groundwater contamination from the 7th Street & Arizona Avenue Site

has migrated downgradient and comingled with contamination from Stone Avenue Site. The

highest detected concentration of PCE in perched groundwater at the Stone Avenue Site was

1,600 μg/L in 7AZP-19, prior to SVE treatment. After a little more than a year of SVE system



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operation, the concentration of PCE in perched groundwater has decreased to 110 μg/L (H+A,

2019). TCE has been detected in the perched groundwater at 7AZP-19 at a maximum

concentration of 4.1 μg/L, below the maximum contaminant level (MCL) of 5 μg/L.

PCE has not been detected in the regional aquifer downgradient of the Stone Avenue Site at a

concentration greater than the MCL.

3.5 REMEDIAL OBJECTIVES

The Remedial Objectives (RO) for the Stone Avenue Site are the derived from those established

for the 7th Street & Arizona Avenue Site. The RO Report for the 7th Street & Arizona Avenue Site

was prepared by ADEQ to establish the remedial objectives for the site, in accordance with

requirements established under A.A.C. R18-16-406. The ROs included those listed below

(ADEQ, 2014).

The RO for land use is: To restore soil conditions to the remediation standards for non-residential

use specified in A.A.C. R18-7-203 (specifically background remediation

standards prescribed in R18-7-204, predetermined remediation standards

prescribed in R18-7-205, or site specific remediation standards prescribed in

R18-7-206) that are applicable to the hazardous substances identified

(tetrachloroethene (PCE), TCE and cis-1,2-dichloroethene (cis-DCE)). This

action is needed for the present time and for as long as the level of

contamination in the soil threatens its use as a non-residential property.

The RO for groundwater use is:

The remedial objective for regional groundwater at the site is to protect for

the use of the groundwater supply by the City of Tucson from contamination

at the Site. This action is needed for the present time and for as long as the

level of contamination in the soil threatens the use of the regional

groundwater for municipal uses.



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The land and water use evaluation section of the RI Report for the 7th Street & Arizona Avenue

WQARF Site identified no uses of surface water in the Site vicinity. Therefore, no ROs were

prepared for surface water.

With respect to the Stone Avenue Site, the ROs identified above may be applied with the

exception that land use includes residential use at adjacent properties. Therefore, the proposed

remedial action(s) for the Stone Avenue Site will account for the residential use of adjacent

properties while remediating the source property to non-residential soil standards.



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4.0 FEASIBILITY STUDY RESULTS

No Feasibility Study report has been prepared for the Stone Avenue Site; therefore, this section

summarizes results from the 7th Street & Arizona Avenue FS and their applicability to the Stone

Avenue Site (HGC, 2014b). Pursuant to A.A.C. R18-16-407(A), a remedy should be capable of

achieving ROs. A reference remedy and alternative remedies, pursuant to A.A.C. R18-16-407(E),

must be developed and described in sufficient detail to allow evaluation using the comparison

criteria. The reference remedy must be developed based on best engineering, geological or

hydrogeological judgment and follow scientific standards of practice. Information used in the

assessment includes: 1) the RI report, 2) best available information concerning available remedial

methods and technologies, and 3) a remedy analysis consistent with A.R.S. § 49-282.06 (HGC,

2014c). With respect to the Stone Avenue Site, the above assumptions are applicable, with the

exception that light non-aqueous phase liquid (LNAPL) is not present.

4.1 IDENTIFICATION AND SSCREENING OF REMEDIAL TECHNOLOGIES

The FS Report for the 7th Street & Arizona Avenue Site identified several remediation

technologies for addressing the vadose zone contamination at the Site, including SVE, AS, raining

wells, thermal treatment, multiphase extraction, chemical oxidation, and excavation. These

remedial technologies were screened based on 1) protectiveness, 2) reasonableness, 3)

necessity, 4) cost effectiveness, and 5) technical feasibility. Based on the screening results, SVE,

AS and Electrical Resistive Heat and ISCO were retained for use. For the Stone Avenue Site,

with the exception of AS, these technologies are viable remedial applications to be considered.

The FS Report found that the Perched groundwater is not of beneficial use and therefore does

not need to be remediated since it does not contribute to a soil vapor migration risk. With respect

to the Stone Avenue Site this determination is valid. Therefore, no groundwater remedial

technologies are considered for the perched zone; however, for the protection of the regional

aquifer, remedial strategies including monitoring may be considered for the perched groundwater.

4.2 EVALUATION AND COMPARISON OF THE REMEDIES



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A comparative evaluation was performed for the Reference, Less Aggressive, and More

Aggressive Remedies to demonstrate that each remedial alternative will achieve the ROs in

accordance with A.A.C. R18-16-407(H). The criteria used to evaluate each remedial alternative

included practicability, risk, cost, and benefit. A summary of the evaluation for each remedial

alternative as presented in the FS is presented below (Table 4).

Table 4 – Summary of Remedial Alternatives as presented in FS Alternative Practicability Risk Cost Benefit

Reference Remedy ● Effective

● Minimized ● PCE and TCE must be removed

from the LNAPL $1.2M ● Removes COCs from

LNAPL

More Aggressive Remedy

● Potential to remove 99% PCE. ● Limitations: electrical

infrastructure; loss of property use during remediation.

● Escape of contaminants above

land surface. ● Use of high voltage

$7.0M ● Shorter timeline ● Potential 99% removal

of COC,

Less Aggressive Remedy

● Less effective. ● LNAPL will be continuing source

● LNAPL would continue to be a

long-term potential threat to groundwater and ambient air.

$1.1M ● Easy to implement ● Lease disruptive to site

use.

4.3 PROPOSED REMEDY

The proposed remedy for the Site must address the contaminated soil in a manner that achieves

compliance with A.A.C. R18-16-406G and will achieve the ROs for the use of the property. Soil

remediation levels will be achieved by remediating to a non-residential remediation level based

on predetermined remediation standards per A.A.C. R18-7-205. The remedy chosen as the

proposed remedy in the FS Report for the 7th Street & Arizona Avenue Site was the Reference

Remedy.

The proposed Remedy was chosen based on a combination of remedial effectiveness,

practicability, cost, risk and benefit. The remedy implementation at the former Oliver’s Cleaners

property and at the Stone Avenue site are expected to decrease soil vapor levels and decrease

the potential for vapor migration from the subsurface. Furthermore, a long-term program to

monitor contaminants in the perched groundwater, the regional aquifer and soil vapor at both sites

will be necessary. The proposed remedy was chosen because it will achieve the ROs, it meets

the remedial action criteria pursuant to A.R.S. §49-282.06, and is consistent with current and

future land and water use.



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With respect to the Stone Avenue Site, the proposed remedy is consistent with the FS Report

Reference remedy for the 7th Street and Arizona Avenue site without the air sparging component.

Additional monitoring of wells associated with the Stone Avenue site will be incorporated into the

costs and Proposed remedy for the 7th Street and Arizona Avenue WQARF site. Monitoring of the

regional aquifer and performance of a remedial optimization program (once every three years)

will also to be added to the remedy.



15

5.0 PROPOSED REMEDY AND ESTIMATED OST

The proposed remedy presented in the FS Report and PRAP is consistent with the remedial

alternative proposed in this PRAP-Addendum, but some changes have been made to

accommodate differences between the Oliver’s Cleaners property and the Stone Avenue Site.

5.1 REMEDY DESCRIPTION

The Proposed Remedy includes remedial technologies and strategies for remediating the soil at

the Stone Avenue Site and protecting the regional groundwater. Each of these remedial

technologies and/or strategies are described in the following subsections.

5.1.1 Proposed Remedy – Vadose Zone

Soil

Concentrations of PCE have historically been detected in soil beneath the Stone Avenue Site

above residential and industrial SRLs. Direct remediation of the soil (e.g. excavation, thermal

treatment) is difficult and cost-prohibitive because of the existing structure and depth of

contamination. Remediation of PCE in the soil will be achieved as an indirect byproduct of the

remediation of soil vapor described below. As PCE-laden soil vapor is removed by the SVE

system, PCE previously adsorbed to soil will volatilize into soil pores and be removed by the SVE

system for treatment. The ADEQ Groundwater Protection Leaching (GPL) Model was used to

calculate the equilibrium concentration of PCE in soil and soil vapor (ADEQ, 2019). The target

remedial concentration of PCE in soil vapor will be 367 μg/m3 and 1,567 μg/m3 for residential and

industrial air, respectively. At these soil vapor concentrations the equilibrium concentrations of

PCE in soil will be below the residential and non-residential RSLs (EPA, 2019).

Soil Vapor Extraction

Operation of a SVE system with carbon adsorption for treatment of the process stream is the

proposed remedial action to reduce the concentration of PCE in the vadose zone. The four

existing SVE wells will be utilized for remediation (Figure 8). The goal of reducing PCE in the

vadose zone is to reduce PCE concentrations below the SVSL-residential (367 μg/m3) and SVSL-



16

industrial (1,567 μg/m3) as appropriate to land use. This will also reduce concentrations of PCE

in soil and reduce PCE available for leaching into the perched groundwater. SVE systems

remediate contaminated soil through an in-situ removal process. The SVE process extracts soil

vapors from the subsurface, treats them at the surface, and then discharges the treated vapors

to the atmosphere. SVE was effective in removal of PCE at the Stone Avenue Site during the

ERA phase.

It is anticipated that SVE will be highly effective at reducing PCE in the vadose zone. After

shutdown of the ERA system in April 2019, PCE concentrations rebounded, but not to the high

concentrations observed prior to remedial efforts. It is likely that PCE was less effectively removed

from the finer materials located from 20 feet to 38 feet bls (Figure 5). After shutting down the SVE

system PCE slowly has been volatilizing from the finer materials. To maintain an effective

performance the present layout of four SVE wells will be operated in “pulse mode” (e.g. one

quarter on, followed by one quarter off).

Following the shutdown of the SVE system in April 2019, the rented soil vapor treatment system

was disconnected and returned. Implementation of the remedy will require a new system to be

installed and operated at the Site. The SVE system will be operated until PCE concentrations in

soil vapor remain below SVSLs. This remedial measure will focus on source control through the

removal of VOC mass in the vadose zone, which will mitigate the potential for ongoing

groundwater impacts from residual VOCs. Measurements of operational parameters will be used

to assess system performance and for system optimization. Operational schedules may be

adjusted to enhance VOC removal. ADEQ will oversee the operation of the SVE system.

Operation of the SVE system will require continued compliance with a Pima County Air Quality

Department air permit, along with quarterly SVE performance testing and reporting.

The estimated costs for implementing the vadose zone remedy is $1,368,695 in today’s dollars.

A breakout of this cost is presented in Appendix A. The estimated cost include a 10% contingency

and assumes the SVE system will be in operation for five years. Estimated costs include: system

planning, system construction, operation and maintenance, and closure (Appendix A). Vapor-

phase granular activated carbon (VGAC) change-outs for the SVE system are assumed to occur



17

on an annual basis. Estimated closeout costs include disposal of VGAC, proper abandonment of

the SVE extraction wells and removal of equipment.

5.1.2 Proposed Remedy – Groundwater

According to the PRAP: “Monitoring of perched groundwater will be performed to demonstrate

that contaminant concentrations in the perched groundwater are decreasing to levels below

regulatory standards. Planned additional monitoring wells in the perched groundwater will allow

for better definition of hydraulic gradients and groundwater flow direction in the distal portion of

the solute plume. Long-term monitoring of VOCs and geochemical parameters in perched

groundwater will continue until soil vapor levels have decreased to acceptable levels and until

AWQS have been met.”

The proposed remedy for groundwater will be monitoring. The proposed monitoring program will

include routine groundwater monitoring and sampling to evaluate plume migration, plume stability,

and natural attenuation of the plume. The current monitoring program includes annual water level

monitoring and collection of groundwater and/or LNAPL samples for VOC analysis from the

current monitoring well network. Soil vapor sampling is not included in the current monitoring

program. The current annual monitoring program includes water level measurements from 42

perched and five regional monitor wells. Thirty-three groundwater samples are collected and

analyzed for VOCs from 25 monitor wells (20 perched and 5 regional). As the impacted plume

decreases in size over time, the monitoring frequency may be reduced and the number of wells

selected for groundwater monitoring and sampling may be decreased. The number of wells and

the frequency of monitoring will be evaluated and updated as necessary, and documented in the

Periodic Reviews of remedy results. ADEQ will oversee the monitoring program.

The estimated costs for implementing the proposed groundwater remedy is $1,645,205 in today’s

dollars (Appendix A). The overall duration of groundwater monitoring is 30 years. The estimated

annual cost for groundwater monitoring includes labor and materials for groundwater collection

(33 samples from 25 monitor wells), laboratory analytical costs, reporting, proper well

abandonment at project closeout, project management, and a 10% contingency.



18

5.2 PERFORMANCE MONITORING AND PERIODIC REVIEWS

Inspections, performance monitoring, and periodic reviews will be used to judge the effectiveness

and adequacy of the remedy. The monitoring will include the following:

SVE System Monitoring – Routine process monitoring will be conducted during the operation of the SVE system to assess remedial progress and system performance. The process monitoring will include the collection of samples from SVE wells and the carbon adsorption system.

Soil Vapor Confirmation Sampling – Performing soil vapor confirmation sampling of nearby soil vapor probes to assess remedial progress and SVE effectiveness.

Periodic monitoring of Perched Zone and Regional Aquifer monitor wells to assess groundwater conditions and verify protection of regional aquifer source.

Remedial Optimization – Remedial Optimization reviews of remedial progress will be conducted at a minimum, every three years.

5.3 ESTIMATED COST

The estimated capital and operational cost of the Proposed Remedy is:

Recommended Remedy – Vadose Zone $1,368,695

Recommended Remedy – Groundwater $1,645,205

Total $3,013,900

The detailed costs are presented in Appendix A.

5.4 DURATION

The overall duration of the proposed remedy is up to five years for operation of the SVE system

and 30 years for groundwater monitoring. The overall duration is the estimated number of years

required for the Proposed Remedy to achieve the ROs.

5.5 CONTINGENCIES

ADEQ may elect to perform additional activities at the Site. Below are some potential

contingencies with general costs.



19

5.5.1 Additional Soil Vapor Extraction Time

If VOC concentration in soil vapor continue to exceed SVSLs after three years the SVE system

may be operated for up to an additional five years. The estimated cost range for this contingency

is $800,000 to $1,000,000.

5.5.2 Additional Soil Vapor Extraction Wells

If the SVE system is ineffective over portions of the site, then additional SVE wells may be

required for installation. The estimated cost range for this contingency is $30,000 to $45,000 for

each additional SVE well.

5.5.3 Additional Regional Groundwater Monitor Wells

Two to three additional regional aquifer wells may be installed near the Stone Avenue Site to

determine flow direction and confirm regional aquifer is not impacted by 7th Street & Arizona

Avenue WQARF Site contaminants. The estimated cost range for this contingency is $45,000 to

$80,000 for each well.

5.5.4 Additional Perched Groundwater Monitor Wells

Additional perched zone monitor wells may be installed down-gradient of the Stone Avenue Site

to better characterize the perched groundwater in the vicinity. The estimated cost range for this

contingency is $30,000 to $45,000 for each well.



20

5.5.5 Regional Aquifer Remediation

Contingent remedial actions may be initiated if 7th Street & Arizona Avenue Site-related VOCs are

detected in the regional aquifer. If COCs are detected above AWQS in the regional aquifer, an

investigation may be performed to:

identify the contamination pathway;

determine the nature and extent of the contamination;

evaluate the anticipated use of regional aquifer in the vicinity of the contamination;

evaluate remedial alternatives;

conduct remedial actions. A potential scope and cost for performing this contingency cannot be provided because the

numerous uncertainties.



21

6.0 CONSIDERATION OF REMEDIATION GOALS AND SELECTION FACTORS

Pursuant to A.A.C. R18-16-408(B)(2) and A.R.S. §49-287.04(A)(4), this section presents how the

remediation goals and selection factors outlined in A.R.S. §49-282.06 and the rules adopted by

the ADEQ Director have been considered for the Proposed Remedy. Additionally, pursuant to

§49-287.04(B) and §49-287.04(C), this section presents details regarding the submission of, and

time frame for, public comments on the PRAP.

6.1 RATIONALE FOR SELECTION OF THE REMEDY

The Proposed Remedy includes source control, mass reduction and monitoring of contamination.

The Proposed Remedy provides the best combination of remedial effectiveness, practicability,

cost, and benefit for the restoration of land use and protection of groundwater resources. There

are currently no unmitigated human health risks associated with the contamination at the Site.

The components of the Proposed Remedy will be protective of the public health and the

environment.

Each component of the Proposed Remedy is a proven, reliable remedial alternative that will be

protective of the public health and the environment. The risk to human health and the environment

with this remedy is low and all known exposure pathways have been addressed. Over time, the

remedial actions will reduce the concentrations and the volume of contaminated soil, soil vapor,

and groundwater at the Site. Environmental sampling and groundwater monitoring are included

to verify that the remedy is protective of public health and the environment during and after remedy

implementation. The combined components of the Proposed Remedy are consistent with current

and anticipated future land and resource use. Upon implementation, this remedy is considered to

have a positive impact in terms of enhancement of future land uses and impacts on local

economies.



22

6.2 ACHIEVEMENT OF REMEDIAL OBJECTIVES

Per A.A.C. R18-16-408(B)(3), the Proposed Remedy must achieve each of the ROs established

by ADEQ for the Site as presented in this PRAP.

The Proposed Remedy will achieve ROs for land use by treating the source of contamination in

soils with SVE until COCs meet background remediation standards prescribed in R18-7-204,

predetermined remediation standards prescribed in R18-7-205, or Site-specific remediation

standards prescribed in R18-7-206. Soil vapor sampling and SVE rebound testing will be used to

confirm the land use ROs are being met.

As per the PRAP “Reduction of chlorinated organic concentrations to meet AWQS in perched

groundwater is not considered an RO since the perched groundwater at the Site is not considered

a potable source. However, the proposed remedy will also reduce the transfer of COCs to the

perched groundwater and will protect the regional aquifer.” Additionally, long-term monitoring of

the Perched Zone and Regional Aquifer will help verify that the maximum beneficial use of water

of the State is maintained.

6.3 ACHIEVEMENT OF REMEDIAL ACTION CRITERIA

In direct accordance with the requirements of A.R.S. §49-282.06, remedial actions shall:

1. Assure the protection of public health and welfare and the environment. 2. To the extent practicable, provide for the control, management or cleanup of the

hazardous substances in order to allow the maximum beneficial use of the waters of the state.

3. Be reasonable, necessary, cost-effective and technically feasible.

As demonstrated in this PRAP-Addendum, the Proposed Remedy for the Site meets the

requirements of A.R.S. §49-282.06. The Proposed Remedy is protective of human health and the

environment, compliant with applicable laws, and allows for the maximum beneficial use of the

waters of the State with the lowest cost. The Proposed Remedy is the best combination of

practicability, risk, cost, and benefit to achieve the ROs.



23

6.4 CONSISTENCY WITH WATER MANAGEMENT PLANS

The Proposed Remedy is consistent with the water management plans of local water providers

and designed to protect the regional aquifer. The remedy will allow for the maximum beneficial

use of the waters of the State, protect the groundwater supply for future use, and ensure that

future water-development options are not impacted over wider areas than is currently the case.

6.5 CONSISTENCY WITH GENERAL LAND USE PLANNING

The Proposed Remedy is consistent with the existing land use and is not anticipated to negatively

impact current or future land use at the property.

6.6 LEAD AGENCY STATEMENT FOR PROPOSED REMEDY

Based on the information currently available, ADEQ believes the Proposed Remedy provides the

best balance of tradeoffs among the other alternatives with respect to the comparison criteria.

ADEQ expects the Proposed Remedy will satisfy the remedial action criteria pursuant to A.R.S.

§49-282.06 and the ROs.

6.7 PUBLIC COMMENT PERIOD

In accordance with the Community Involvement Plan (ADEQ, 2016) and A.A.C R18-16-404(E),

ADEQ will provide notice to the public and notification to interested persons of the availability and

the opportunity to comment on the PRAP. Public comment period will be open for a 90-day period.

Written comments on this PRAP-Addendum shall be submitted to ADEQ via email or regular mail.

Public comments shall be submitted to:

Arizona Department of Environmental Quality 400 West Congress Street, Suite 433

Tucson, AZ 85701 Attention: Joshua R. Campbell, E.I.T. Email: [email protected]

mailto:[email protected]



24

7.0 REFERENCES

ADEQ, 2014. Remedial Objectives Report, 7th Street and Arizona Avenue, Water Quality

Assurance Revolving Fund Site, Tucson, Arizona. March 21, 2014.

_____, 2016. 7th Street and Arizona Avenue and Park-Euclid, Water Quality Assurance Revolving

Fund (WQARF) Sites, Tucson, Arizona, Community Involvement Plan. 2016.

_____, 2019. Groundwater Protection Leaching (GPL) Model. 2019.

http://www.azdeq.gov/groundwater-protection

Environmental Protection Agency (EPA), 2019. Regional Screening Level (RSL) Summary Table

(TR=1E-06, HQ=1) November 2019.

Hargis + Associates (H+A), 2016. Technical Memorandum titled: 7th Street and Arizona Avenue

WQARF Site – Summary of Installation and Initial Sampling of Monitor Well and Soil Vapor

Probes at 847 N. Stone Avenue, Tucson, Arizona. June 30, 2016.

_____, 2017. 7th Street and Arizona Avenue WQARF Site – Summary of Drilling and Monitor

Well Installation Activities, Toe of the Plume Investigation, Tucson, Arizona. June 29,

2017.

_____, 2019. Summary of Groundwater Monitoring Activities, July 2018 to June 2019,

7th Street and Arizona Avenue WQARF Site. June 20, 2019.

Hydro Geo Chem (HGC), 2014a. Remedial Investigation Report, 7th Street and Arizona Avenue

WQARF Site, Tucson, Arizona. March 21, 2014.

_____, 2014b. Feasibility Study Report, 7th Street and Arizona Avenue WQARF Site, Tucson,

Arizona. April 24, 2014.



25

_____, 2014c. Proposed Remedial Action Plan, 7th Street and Arizona Avenue WQARF Site,

Tucson, Arizona. April 28, 2014.

_____, 2019. October 2019 Soil Vapor Rebound Sampling 7th Street & Arizona Avenue WQARF

Site, 847 North Stone Avenue, Tucson, Arizona. November 18, 2019.

Terracon Consultants, Inc. (Terracon), 2013. Phase I Environmental Site Assessment, North

Stone Avenue and West 2nd Street, 847 North Stone Avenue, Tucson, Pima County AZ.

February 5, 2013.

_____, 2014. Limited Site Investigation, North Stone Avenue and West 2nd Street, 847 North

Stone Avenue, Tucson, Pima County Arizona, Community Wide Brownfield Assessment

Grant, Grant ID Number BF-00T50201. January 16, 2014.

URS, 2017. Notice of Completion for Second Phase of SVE System Construction and

Documentation of Preceding Activities, ERA for 7th Street and Arizona Avenue WQARF

Site, 847 North Stone Avenue Property, Tucson, AZ. October 31, 2017.


TABLES

Depth PCELocation Date (ft bls) µg/m3

SG1 Apr-99 Ranging 2.5 - 4ft 460,000SG2 Apr-99 Ranging 2.5 - 4ft 91,000SG3 Apr-99 Ranging 2.5 - 4ft 15,000,000SG4 Apr-99 Ranging 2.5 - 4ft 3,100,000SG5 Apr-99 Ranging 2.5 - 4ft 56,000,000SG6 Apr-99 Ranging 2.5 - 4ft 21,000,000SG7 Apr-99 Ranging 2.5 - 4ft 180,000V-6 Nov-13 Sub-Slab 1,400,000V-7 Nov-13 Sub-Slab 1,500,000V-8 Nov-13 Sub-Slab 1,700,000V-9 Nov-13 Sub-Slab 350,000

RESIDENTIAL SRL (Risk 10-6) 510 NON-RESIDENTIAL SRL 13,000

ACRONYMS/ABBREVIATIONS:µg/m3 = Micrograms per cubic meterADEQ = Arizona Department of Environmental Quality

ft = feetft bls = feet below land surfacePCE = Tetrachloroethene

Risk 10-6 = Carcinogen risk level of 10-6SRL = Soil Remediation Levels

NOTES:Locations of SG1 to SG-7 undetermined

TABLE 1

TETRACHLOROETHENE IN SOIL VAPORPre-ADEQ Investigations

1195.01_H01_PRAP_Tble 11/22/2020 Page 1 of 1

Depth PCE

Location Date (ft bls) mg/kgSB-1 Oct-99 0 ND '' '' '' '' 5 0.42 '' '' '' '' 10 0.50 '' '' '' '' 15 1.40 '' '' '' '' 20 1.80 '' '' '' '' 25 1.70 '' '' '' '' 30 3.40 '' '' '' '' 35 4.60 '' '' '' '' 40 ND '' '' '' '' 45 0.10

SB-2 Oct-99 2 3.40 '' '' '' '' 5 0.70 '' '' '' '' 10 1.50 '' '' '' '' 15 0.17 '' '' '' '' 20 1.80 '' '' '' '' 25 1.70 '' '' '' '' 30 4.70 '' '' '' '' 35 4.30 '' '' '' '' 40 0.19 '' '' '' '' 45 0.22 '' '' '' '' 50 ND '' '' '' '' 55 1.60

SB-3 Oct-99 0 4.10 '' '' '' '' 5 5.10 '' '' '' '' 10 0.42 '' '' '' '' 15 ND

HL-1 Oct-13 4 0.93 '' '' '' '' 7.5 1,800.00 '' '' '' '' 10 440.00 '' '' '' '' 13 8.20

HL-2 Oct-13 4 0.21HL-3 Oct-13 10 0.30HL-4 Oct-13 15 0.12GW-5 Oct-13 5 0.12 '' '' '' '' 35 4.70 '' '' '' '' 50 0.40 '' '' '' '' 85 0.59

7AZP-19 Mar-16 25 0.91 '' '' '' '' 30 1.70 '' '' '' '' 40 0.15

SVE1 May-17 10 <0.29 '' '' '' '' 20 <0.25 '' '' '' '' 30 <0.20 '' '' '' '' 40 <0.23

TABLE 2

SUMMARY OF TETRACHLOROETHENE IN SOIL


Depth PCE

Location Date (ft bls) mg/kg

TABLE 2

SUMMARY OF TETRACHLOROETHENE IN SOIL

'' '' '' '' 50 <0.21 '' '' '' '' 60 <0.20 '' '' '' '' 70 <0.23 '' '' '' '' 80 <0.24 '' '' '' '' 85 <0.22

SVE2 May-17 10 <0.21 '' '' '' '' 20 <0.22 '' '' '' '' 30 1.89 '' '' '' '' 40 <0.23 '' '' '' '' 50 <0.23 '' '' '' '' 60 <0.22 '' '' '' '' 70 <0.24 '' '' '' '' 80 <0.17 '' '' '' '' 85 <0.22

SVE-3 May-17 10 0.18 '' '' '' '' 20 <0.26 '' '' '' '' 30 0.10 '' '' '' '' 40 <0.21 '' '' '' '' 50 <0.22 '' '' '' '' 60 <0.20 '' '' '' '' 70 <0.21 '' '' '' '' 80 <0.19 '' '' '' '' 85 <0.20

SVE4 May-17 10 <0.26 '' '' '' '' 20 <0.24 '' '' '' '' 30 0.09 '' '' '' '' 40 0.18 '' '' '' '' 50 <0.24 '' '' '' '' 60 <0.20 '' '' '' '' 70 1.07 '' '' '' '' 80 <0.17 '' '' '' '' 85 <0.20

RESIDENTIAL SRL (Risk 10-6) 0.51 NON-RESIDENTIAL SRL 13

ACRONYMS/ABBREVIATIONS:mg/kg = Milligrams per kilogram

ft bls = feet below land surfacePCE = TetrachloroetheneSRL = Soil Remediation Levels

Risk 10-6 = Carcinogen risk level of 10-6


TABLE 3

SUMMARY OF TETRACHLOROETHENE IN SOIL VAPOR

ADEQ Investigations

5/17: Apartment Sub Slab SystemDec17/Jan18: ERA SVE Rebound Testing Rebound Testing

Mar-16 Mar-17 Nov/Dec-17 Apr-18 Jun/Jul-18 Nov-18 May-19 Oct-19Depth Date PCE PCE PCE PCE PCE PCE PCE PCE

Location Easting Northing (ft bls) Constructed (µg/m3) (µg/m3) (µg/m3) (µg/m3) (µg/m3) (µg/m3) (µg/m3) (µg/m3)

SA-SVP-1 992005 449704.3 5 Mar-16 340,000 108,500 395 66.0 2,020 SA-SVP-2 992035.1 449701.9 5 Mar-16 340,000 154,600 476 87.7 2,480 SA-SVP-3 992067.4 449631.8 5 Mar-16 760,000 75,940 329 60.9 326 SA-SVP-4 992010.9 449619.3 5 Mar-16 4,400,000 101,000 3,264 508 2,820 SA_SVP-5 992067 449585 5 Feb-17 189,162 75.5 209 33.5 53.6

" " " " " " 14.5 " " 1,146,000 766,100 854 590 134 SA_SVP-6 992029 449584 5 Feb-17 772,900 25,560 402 <13.6 477

" " " " " " 14.5 " " 5,249,000 3,885,000 2,690 2,260 14,600 SA_SVP-7 991985 449584 7.5 Feb-17 901,700 307 63 171 20.4

" " " " " " 13.7 " " 1,220,000 158,000 12,407 340 5,780 SA_SVP-8 991828 449671 5.5 Feb-17 7,797 2,414 8 19.9 <13.6 65.6

" " " " " " 14.5 " " 21,221 2,595 111 41.1 13.8 7.2 SA_SVP-9 991923.5 449767 5 Mar-18 1,200 399 248 91 1,980

" " " " " " 9.5 " " 1,890 426 307 70 1,360 SA_SVP-10 992003.5 449767 5 Mar-18 8,270 8,540 2,120 1,150 107

" " " " " " 11 " " 4,070 3,450 1,500 816 14,000 7AZP-19 992025.6 449643 15 Mar-16 6,400,000 867,800 72,550 13,600 4,180 " " " " " " 40 " " 6,400,000 1,950,000 68,480 15,700 56,900 " " " " " " 60 " " 6,500,000 2,115,000 52,210 12,100 21,800 " " " " " " 72 " " 7,500,000 2,509,000 47,870 12,800 20,300 SVE-1S 992019 449696 6-21 May-17 97,000 <2,000 1,808 6,000 SVE-1M " " " " 26- 36 " " 160,000 <2,000 3,617 6,690 SVE-1D " " " " 41-86 " " 3,600,000 10,000 10,601 5,040 SVE-2S 992023 449669 6-21 May-17 150,000 <2,000 106 26,800 SVE-2M " " " " 26- 36 " " 430,000 <2,000 3,860 20,200 SVE-2D " " " " 40-83 " " 3,800,000 9,500 243 41,800 SVE-3S 992006 449621 6-21 May-17 830,000 7,900 94 44,500 SVE-3M " " " " 26- 36 " " 1,100,000 370,000 5,862 202,000 SVE-3D " " " " 41-86 " " <2,000 23,000 87 1,402,000 SVE-4S 991971 449652 6-21 May-17 330,000 13,000 <2.5 16,300 SVE-4M " " " " 26- 36 " " 980,000 11,000 1,808 9,980 SVE-4D " " " " 41-86 " " 5,200,000 4,700 32 52,300

TEMPORARY SOIL VAPOR PROBESSA-TVP-1 991989.9 449725.6 5 Mar-16 150,000 SA-TVP-2 992035.7 449725.8 5 Mar-16 210,000SA-TVP-3 992065.3 449727.9 5 Mar-16 160,000SA-TVP-4 992118.3 449687.6 5 Mar-16 190,000SA-TVP-5 992118.3 449648.3 5 Mar-16 380,000SA-TVP-6 992062.7 449603.1 5 Mar-16 350,000SA-TVP-7 992035.9 449602.4 5 Mar-16 1,100,000SA-TVP-8 992008 449600.7 5 Mar-16 1,900,000SA-TVP-9 991952.1 449650.7 5 Mar-16 740,000

SA-TVP-10 991955.4 449708.1 5 Mar-16 140,000SA_TVP-11S 991704 449595 5 Mar-18 55.6SA_TVP-11D " " " " 14 " " 52.5SA_TVP-12S 991704 449683 5 Mar-18 98.6SA_TVP-12D " " " " 13 " " 72.2SA_TVP-13S 991923.5 449767 5 Mar-18 1,200 SA_TVP-13D " " " " 9.5 " " 1,890 SA_TVP-14S 992003.5 449767 5 Mar-18 8,270 SA_TVP-14D " " " " 11 " " 4,070

ACRONYMS/ABBREVIATIONS:µg/m3 = Micrograms per Cubic MeterADEQ = Arizona Department of Environmental Quality

ft bls = feet below land surfacePCE = Tetrachloroethene

ERA SVE = Early Response Action soil vapor extractionGray Cell = No sample collected

NOTES:Temporary Soil Vapor Probes : SA_TVP-13S/D and SA_TVP-14S/D were converted into permant soil vapor probes SA_SVP-9 and SA_SVP-10 respectivley.



FIGURES

I

0 0.2 0.40.1 Miles

FIGURE 1: SITE LOCATION

SPEEDWAY BLVD.

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(as per Remedial InvestigationReport dated March 21, 2014)

EXTENT OF LIGHT NON-AQUEOUSPHASE LIQUID OVER PERCHED

GROUNDWATER

(as per Remedial InvestigationReport dated March 21, 2014)

HARGIS + ASSOCIATES, INC.Hydrogeology/Engineering

Preliminary Remedial Action Plan 7th & Arizona WQARF Site, Tucson, Arizona

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APARTMENTS

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V-7 V-8

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SB-2SB-3

HL-1 HL-3

FIGURE 2: SITE PLAN

I30 0 3015 Feet

EXPLANATION


Photograph Source: Pima County

Boring!

Sub-Slab Sample")

Monitor Well!U

SA-TVP-12 Location Identifier

Soil Vapor Extraction Well#I

Temporary Soil Vapor Probe#*Permanent Soil Vapor Probe#


# # #

#

#

###

#

# # #

#

#

#

###

#

#* #* #*

#*

#*

#*#*#*

#*

#*

#*

#*

#* #*

#0

#0

#0

#0

SA-TVP-12

SA-TVP-11

SA-SVP-8

W. 2ND STREET

N.STO

NE AV

ENU

E

APARTMENTS

SAHARA APARTMENTS

847 N. STONE AVE.

N.9TH

AVE

NU

E

SA-SVP-1 SA-SVP-2

SA-SVP-3

SA-SVP-4

7AZP-19

SA-SVP-7

SA-SVP-6

SA-SVP-5

SA-TVP-13 /SA-SVP-9

SA-TVP-14 /SA-SVP-10

SA-TVP-1 SA-TVP-2 SA-TVP-3

SA-TVP-4

SA-TVP-5

SA-TVP-6SA-TVP-7

SA-TVP-8

SA-TVP-9

SA-TVP-10

108,500 (5') 154,600 (5')

867,800 (15')1,950,000 (40')2,115,000 (60')2,509,000 (72')

75,940 (5')101,000 (5')

25,560 (5')3,885,000 (14.5')

307 (7.5')158,000 (13.7')

75.5 (5.5')766,100 (14.5')

2,414 (5.5')2,595 (14.5')

98.6 (5')72.2 (11')

55.6 (5')52.5 (11')

1,200 (5')1,890 (9.6')

8,270 (5')4,000 (11')

150,000 (5') 210,000 (5') 160,000 (5')

190,000 (5')

380,000 (5')

350,000 (5')1,100,000 (5')

1,900,000 (5')

740,000 (5')

140,000 (5')SVE-1

SVE-2

SVE-3SVE-4

97,000 (6-21')160,000 (26-36')

3,600,000 (41-86')150,000 (6-21')

430,000 (26-36')3,800,000 (40-83')

830,000 (6-21')1,100,000 (26-36')

<2,000 (41-86')

330,000 (6-21')980,000 (26-36')

5,200,000 (41-86')

FIGURE 3: MAXIMUM CONCENTRATION OF TETRACHLOROETHENE IN SOIL VAPOR

I30 0 3015 Feet

EXPLANATION



Soil Vapor Extraction Well#0

Temporary Soil Vapor Probe#*Permanent Soil Vapor Probe#

Concentration in micrograms per cubic meter(Sample depth in feet)

SA-TVP-12

98.6 (5')Location Identifier


# #

#

#

#

#0

#0

#0

#0

# #

#

#

###

#

SA-SVP-8

W. 2ND STREET

N.STO

NE AV

ENU

E

APARTMENTS

SAHARA APARTMENTS

847 N. STONE AVE.

N.9TH

AVE

NU

E

#

SA-SVP-1 SA-SVP-2

SA-SVP-3

SA-SVP-4

7AZP-19

SA-SVP-7

SA-SVP-6

SA-SVP-5

SA-SVP-9 SA-SVP-10#

66 (5') 87.7 (5')

13,600 (15')15,700 (40')12,100 (60')12,800 (72')

60.9 (5')508 (5')

<13.6 (5')2,260 (14.5')

171 (7.5')340 (13.7')

33.5 (5.5')590 (14.5')

<13.6 (5.5')13.8 (14.5')

91 (5')70 (9.6')

1,150 (5')816 (11')

SVE-1

SVE-2

SVE-3SVE-4

1,808 (6-21')3,617 (26-36')

10,601 (41-86')106 (6-21')

6,860 (26-36')243 (40-83')

94 (6-21')5,862 (26-36')

243 (41-86')

<2.5 (6-21')1,808 (26-36')

32 (41-86')

FIGURE 4: CONCENTRATION OF TETRACHLOROETHENE IN SOIL VAPOR - MAY 2019

I30 0 3015 Feet

EXPLANATION



Soil Vapor Extraction WellPermanent Soil Vapor Probe

Concentration in micrograms per cubic meter(Sample depth in feet)

SA-TVP-12

98.6 (5')Location Identifier

#I#


FIGURE 5: CROSS SECTION A - A’

40 ft 020

20

40 ft

0

11

95

PR

AP

Fig

ure

5 C

ross S

ectio

nA

A’.cd

r


1/8

/20

20


7AZP-19SVE-1 SVE-2 SVE-3 SVE-4

0

0

0.9

0

1.4

12.7

2.3

0.7

0

0.6

0

0.9

0

0

0

0 19.5

18.6

82.5

44.1

65.8

112.2

3

50

0.2

242.6

3.1

1.2

0

0

0.4

0

0

64.365.2

110.5255.4101

7027

66.159.4245

192.925.1

481.418423.814.511.632.469.5838.8883.6467.9

368.4132.377.8

137.3380.975.4

153.5105.3174.6

0.515.586.3

0

0

1.4

3.4

1.4

0

0

8.4

4.2

0.2

0.6

0

0.6

0

0

0

2.8

97,000

160,000

3,600,000

150,000

430,000

3,800,000

830,000

1,100,000

<2,000

330,000

980,000

4,000,000

6,4000,000

6,400,000

6,500,000

7,500,000

2.31.7

1.0

0.0

1.9

392

36.8

41.8

786

242

206

5.0

67.0

2.9

1.7

12.7

10.1

0.7

0.6

0.8

0.8

EXPLANATION

SAND / GRAVEL<15% FINES

PREDOMINANTLYFINES

FILTER

SEAL

SAND / GRAVEL15% FINES≥

SCREEN

SILTY/CLAYEYSANDS/GRAVELS

SANDS/GRAVELS

SANDY / CLAYEYSILT / CLAY

SILT / CLAY

WATERLEVEL

LOCATION

A

A’

A A’

1.4

150,000

PID READING(ppm)

PCE inSOIL

VAPOR(ug/M3)

SCALE

ug/M3 = Miscogram per Cubic Meter

ppm = Parts Per Million

ft = Feet

PCE = Tetrachloroethene

NOTE

10

20

30

40

50

60

70

80

90

DE

PT

H B

EL

OW

LA

ND

SU

RF

AC

E

0

100

10

20

30

40

50

60

70

80

90

DE

PT

H B

EL

OW

LA

ND

SU

RF

AC

E

0

100

1,808

3,617

10,601

106

6.860

243

94

5,862

87

13,600

15,700

12,100

12,800

<2.5

1,808

32

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Pre-SVE

Post SVE

Post SVE

Post SVE

Post SVE

Post SVE

Pre-SVE

Pre-SVE

Pre-SVE

Pre-SVE

Post SVE

Post SVE

Pre-SVE

Pre-SVE

Post SVE

Post SVE

Pre-SVE

Pre-SVE

106Pre-SVE

Post SVE

Pre-SVE = Maximum Concentration Prior to SVE OperationPost SVE = Initial Concentration After SVE Operation

SVE = Soil Vapor Extraction

LegendMonitor Well w No LNAPL

Monitor Well with LNAPL

PCE Plume 2018

1st St.

2nd St.

University Blvd

4th St.

5th St.

Ston

e Av

e.

Speedway Blvd

847 Stone Ave

Former Oliver's Cleaners

6th St.

7th St.

4th

Ave

5th

Ave

6th

Ave

7th

Ave

9th

Ave

Tetrachloroethene Solute Plume(as per Remedial Investigation Report, March 2014)

2017 Tetrachloroethene Solute Plume

7AZP-20<0.50

7AZP-111.4

7AZP-93.4

7AZP-19110

7AZP-15<0.50

7AZP-64.4

7AZP-50.73 7AZP-13

<0.50MW-PD-304.5

BF-3<0.50

BF-12.2

MW-PD-40<0.50

YC-6<25,000

MW-PD-28<0.50MW-PD-29

0.56YC-595,000

7AZP-2240,000

7AZP-12.9

MW-PD-5<0.50 MW-PD-42

<0.50

MW-PD-25<0.50

MW-PD-26<0.50

MW-PD-43<0.50

0 0.30.15 Miles

NOTE:LNAPL = Light Non-Aqueous Phase LiquidGroundwater results in = Micrograms per liter (ug/l)LNAPL results in = Micrograms per kilogram (ug/kg)

2018 Tetrachloroethene Solute Plume

?

??

FIGURE 6: TETRACHLOROETHENE IN GROUNDWATER - PERCHED AQUIFER Preliminary Remedial Action Plan 7th & Arizona WQARF Site, Tucson, Arizona

??

?

7AZR-5

?

??? ???

?

Effective Aquitard

RegionalGroundwater

PerchedGroundwater

2,350

2,300

2,250

2,200

BNORTH

B’SOUTH

2,350

2,300

2,250

2,200

ELE

VA

TIO

N

(fe

et

mean s

ea level)

2,150

7AZB-3

2,150

STONE AVE SITE FORMER OLIVER’S LAUNDRY7AZP-6(Projected)

7AZP-9(Projected)

7AZP-14(Projected) 7AZP-4

7AZR-1

7AZP-12(Projected)

MW PD-67AZR-3

MW-PD-30BF-1

(MW-1)BF-3

7AZP-19

7AZP-20

0.32 ug/l PCE

1,300 ug/l PCE

34 ug/l PCE

110 ug/l PCE

?

FIGURE 7: CROSS SECTION B - B' LOCATIONHARGIS + ASSOCIATES, INC.Hydrogeology/Engineering

EXPLANATION

Well &Screen

PCE = Tetrachloroetheneug/l = Micrograms per liter

400 ft0 200

LOCATION

Horizontal Scale

!(

!(

!(

!(

!(

!(

!(

!(

!(!(!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(!(

!(

!(

!(

!(

!(

!(

!(!(

!(

B

B’


Fill/Other

PredominantlyFines

Sand / Gravel15% Fines≥

Silty / Clayey Sands / Gravels

Sands / Gravels

Sandy/ClayeySilt/Clay

Silt/Clay

Not Assigned

Sand / Gravel15% Fines<

Water Level

Aquitard

1195

PR

AP

Fig

ure

7 C

ross

Sect

ion B

B.c

dr

1/8

/2020

Effective Aquitard

? Effective Aquitard ?

SVE-4

SVE-1

EDGE OF FORMERCONCRETE RAMP

11' WIDE x 26' LONGSVE FENCEDCOMPOUND

EXISTINGROLL GATE

ROLLING OVERHEADGARAGE DOOR

13' 10'

11'

26'

GAC-2

GAC-1

TRAILER-MOUNTEDSVE BLOWER

EDGE OFCONCRETEPAVEMENT

LANDSCAPE AREA

4'

19'

5'

36'

PAVEMENT JOINT(NO CONCRETE RESTORATION

FOR TRENCH NORTH OF THISJOINT)

12'

11.5'

SVE-2

EXISTING SUMP

EXISTING SEWER LINE

EXISTING 10' HIGHCHAIN LINK FENCE

EXISTING VEHICLE LIFT(TYP OF 4)

CONCRETE

CONCRETE

CONCRETE

LEGENDEXISTING CHAIN LINK FENCE

NEW CHAIN LINK FENCE

SANITARY SEWER LINE

EDGE OF CONCRETE

NEW WELLHEAD VAULT

EXISTING BUILDING WALL

SVE PIPE TRENCH

SOIL VAPOR EXTRACTION

GRANULAR ACTIVATED CARBON

SVE

GAC

NEW 10' WIDE DOUBLEHUNG SWING GATEINSTALLED ON EXISTINGFENCE WITH 5' W x 10' HPANELS

SVE PIPE MANIFOLD

18"

SVE-3

WAREHOUSEBUILDING

SHOPBUILDING

URS PROJECT NO:

DRAWN BY:

DESIGNED BY:

SHEET TITLE

CHECKED BY:

PLOT DATE:

SCALE:

ACAD VER:

DATE CREATED:

URS Group Inc.7720 North 16th Street, Suite 100

Phoenix, AZ 85020602-371-1100 (phone)

602-371-1615 (fax)

SVE REMEDIATION SYSTEM847 NORTH STONE AVE

TUCSON, AZ

NSITE LAYOUT PLAN

LMR

JR, WP

JR

6/20/2018

AS NOTED

60541366

AutoCAD 2014

6/20/2018

SVE SYSTEM LAYOUTPLAN

FIGURE 8: SVE SYSTEM LAYOUTPreliminary Remedial Action Plan 7th & Arizona WQARF Site, Tucson, Arizona


APPENDIX A

DETAILED COST INFORMATION FOR THE REMEDIAL ALTERNATIVE

$23,000 LS 1 $23,000$3,000 LS 1 $3,000$7,000 LS 2 $14,000$1,500 LS 2 $3,000

$100 LS 1 $100$1,160 LS 1 $1,160

Total $44,260

$28,000 LS 1 $28,000$15,650 LS 1 $15,650$3,700 LS 1 $3,700

$31,000 LS 1 $31,000$11,400 LS 1 $11,400$6,175 LS 1 $6,175

Total $95,925

$122,000 YR 1 $122,000$40,800 YR 1 $40,800$16,900 YR 1 $16,900$12,000 YR 1 $12,000$16,800 YR 1 $16,800$2,300 Month 6 $13,800$8,880 LS 1 $8,880

Total $231,180

$91,000 YR 2 $182,000$33,600 YR 2 $67,200$16,600 YR 2 $33,200$7,700 YR 2 $15,400

$13,200 YR 2 $26,400$5,000 LS 1 $5,000$2,300 Month 12 $27,600

$17,480 LS 1 $17,480Total $374,280

$57,500 YR 2 $115,000$25,600 LS 2 $51,200$12,400 LS 2 $24,800$10,050 LS 2 $20,100$8,400 LS 2 $16,800$2,300 Month 12 $27,600

$14,050 LS 1 $14,050Total $269,550

$110,000 LS 1 $110,000$75,000 LS 1 $75,000$50,000 LS 1 $50,000$20,000 LS 1 $20,000$25,000 LS 1 $25,000$25,000 LS 1 $25,000$19,500 LS 1 $19,500

Total $324,500

SUB-TOTAL $1,339,695LABOR CONTINGENCY (5%) $29,000

TOTAL $1,368,695

ACRONYMS/ABBREVIATIONS:LS = Lump Sum

O&M = Operation & MaintenanceSVE = Soil Vapor Extraction

VOCs = Volatile Organic CompoundsWQARF = Water Quality Assurance Revolving Fund

YR = year

TABLE A-1Proposed Remedy Action Plan - Addendum Cost Breakdown

7th & Arizona WQARF Site

System Decommissioning Contingency 10% (non-labor)

Labor Vapor Rebound Testing Soil Matrix Sampling HHRA Modeling Extraction Well Abandonment

Closure

Routine O&M - Materials/Equipment/Vendors Non-Routine O&M - Materials/Equipment/Vendors System Offline - Labor Electricity, Data Line Contingency 10% (non-labor)

Contingency 10% (non-labor)

SVE System O&M, (Years 4 and 5 of 5) Labor Routine O&M Labor

Routine O&M - Materials/Equipment/Vendors Non-Routine O&M - Materials/Equipment/Vendors System Offline - Labor Remedy Optimization Electricity, Data Line

Contingency 10% (non-labor)

SVE System O&M, (Years 2 and 3 of 5) Labor Routine O&M Labor

Routine O&M Labor Routine O&M - Materials/Equipment/Vendors Non-Routine O&M - Materials/Equipment/Vendors System Offline - Labor Electricity, Data Line

Other Costs Contingency 10% (non-labor)

SVE System O&M, (Year 1 of 5) Labor

SVE System Re-Assembly and Start-Up Labor Sub-contractor (Mechanical/Plimbing) Sub-contractor (Electrical/Control) Drilling & Geotechnical Testing

VPGAC Vessel, 2,000 lb capacity, Includes Delivery VPGAC Initial Fill, 2,000 lb capacity Electric and other costs Contingency 10% (non-labor)

PROPOSED REMEDY

Vadose Zone (VOCs) - Pulsed Operation of SVE systemSVE System Re-Assembly Planning Labor Permit to Operate

1195.01_H01_PRAP_Tbl A-11/22/2020 Page 1 of 1

$23,000 YR 30 $690,000$8,000 YR 30 $240,000$8,000 YR 30 $240,000$5,000 Each 10 $50,000$4,400 YR 30 $132,000

Total $1,352,000

$1,330 Well 35 $46,550$5,500 Well 30 $165,000$7,000 Well 5 $35,000

$20,000 LS 1 $20,000$26,655 LS 1 $26,655

Total $293,205

TOTAL $1,645,205

ACRONYMS/ABBREVIATIONS:LS = Lump sum

VOCs = Volatile Organic CompoundsWQARF = Water Quality Assurance Revolving Fund

YR = year

Contingency 10%

Closure Labor Well Abandonment (Shallow) Well Abandonment (Deeper) Reporting

Remedy Optimization Contingency 10%

Annual Monitoring and Sampling Field Activitites (monitor, sample) Prepare report (data assessment, database upload) Sample analysis, other hard costs

TABLE A-2PROPOSED REMEDY ACTION PLAN - ADDENDUM COST BREAKDOWN

7th & ARIZONA WQARF SITE

PROPOSED REMEDYGroundwater (VOCs) - Annual Monitoring and Sampling

1195.01_H01_PRAP_Tble A-21/22/2020 Page 1 of 1

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