Final Close Out Report

Monroe Auto Equipment Company Site

Paragould, Arkansas

(CERCUS ID ARD980864ll0)

United States Environmental

Protection Agency

Region 6

Superfund Division

April2014

9417788 11111111111111111 IIIII IIIII 11111111111111 1111 004718

CONCURRENCE PAGE FINAL CLOSE OUT REPORT

MONROE AUTO EQUIPMENT COMPANY SUPERFUND SITE EPA ID# ARD98086411 0

411 b4_ Date Brian W. MUeller

Remedial Project Manager, Superfund Remedial Branch

/j .!Ia ~/l kG7~ Carlos Sanchez 7

Chief, Ark/Tx Section, Superfund Remedial Branch

irector, Superfund Remedial Branch

ljj~j_ r Date

ctor, Superfund Remedial Branch

@4/B)f Mark Peycke Date Office of Regional Counsel, Chief, Superfund Branch

tr:~o/11 Date

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SUPERFUND FINAL CLOSE OUT REPORT MONROE AUTO EQUIPMENT COMPANY SUPERFUND SITE EPA ID (ARD980864110) PARAGOULD, ARKANSAS

I. INTRODUCTION

This Final Close Out Report documents that the U.S. Environmental Protection Agency (EPA) has determined, in accordance with Close Out Procedures for National Priorities List Sites (OSWER Directive 9320.2-22, May 2011), that all appropriate response actions at the Monroe Auto Equipment Company Superfund Site (Site) have been successfully implemented by Tenneco Automotive, Inc. in accordance with the September 26, 1996, Record of Decision (ROD) and the November 9, 2000, Record of Decision Amendment (Amendment). The EPA and the Arkansas Depmtment of Environmental Quality (ADEQ) conducted oversight activities during implementation of the remedy.

II. SUMMARY OF SITE CONDITIONS

Site Background

The Monroe Auto Pit Superfund Site, also known as the Finch Road Landfill, is located in northeastern Arkansas in unincorporated Greene County, approximately three miles southwest of Paragould. The Site lies immediately west of Arkansas Highway 358 and is approximately three miles west of its intersection with U.S. Highway 49. The Site lies in the Northwest Quarter of the Northeast Quarter of Section 17, Township 16 North, Range 5 East, in the Paragould West 7.5-minute quadrangle. The southwestern corner of the Site is at latitude 36° 01' 0" and longitude 90° 34' 30". The Site occupies seven (7) acres of a former sand and gravel borrow pit. The area is rural and lightly populated with private residences located immediately south, north, and northeast of the Site.

The Site is owned by Tenneco Automotive, Inc., successor to Monroe Auto Equipment Company, One International Drive, Monroe, Michigan. The property is identified as Parcel No. 4071-l in the Greene County Tax Assessor's office. The legal description provided in the property deed is "all that part of the south half of the Northwest Quarter of the Northeast Quarter of Section 17, Township 16 North, Range 5 East lying west of the Highway No. 358" (Warranty deed 1973).

Land and Resource

The most predominant land use near the site is single-family residences. A field survey identified 52 single-family residences and six mobile homes within a one-mile radius of the site. Many of these are associated with small farms and related agricultural pursuits. Agricultural uses include crop farming and livestock production. The field survey identified four commercial land uses. These land uses were individual enterprises and included antique sales, convenience stores, and

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automobile repair establishments. Industrial land use is limited to gravel quarries. There are no schools, nursing homes, churches, hospitals, or recreational facilities within a one-mile radius of the site.

The Site is located in the northwestern section of the Mississippi River Embankment on the eastern edge of a geomorphic feature known as Crowley's Ridge. Crowley's Ridge is located in eastern Arkansas and southeastern Missouri. Crowley's Ridge is an erosional remnant of unconsolidated coastal plain sediments consisting of Eocene clay, silt, sand and lignite overlain by Pliocene sand and gravel and Pleistocene loess (Guccione, eta!, 1986). Three units of loess deposits have been distinguished on Crowley's Ridge. In recent work by Guccione, et. al., (1986) they were labeled as the Peoria Loess, the Roxana Silt, and the Loveland Silt. The Pliocene sand and gravel, also known as Crowley's Ridge deposits, were formed primarily in braided and meandering stream environments, with some minor deposition in flood plains. The deposits are up to 124 feet in thickness. Eocene deposits underlying the Crowley's Ridge deposits include the Jackson, Clairborne, and Wilcox Groups. The Jackson Group is the uppermost unit and consists of sandy clay, silt, and glauconitic, fossiliferous sandy clay. Underlying the Jackson Group is the Clairborne Group, consisting of fine sand, sandy clay, and minor amounts of lignite. Underlying the Clairborne Group is the Wilcox Group, consisting of interbedded sand, silt, clay, and some lignite. All three units outcrop on Crowley's Ridge; however, in the vicinity of the Site only the Wilcox Group, overlain by Crowley's Ridge deposits, remain.

History of Contamination

Monroe Auto Equipment Company (now Tenneco Automotive, Inc.) purchased the seven-acre tract of land in Greene County, Arkansas in 1973. The Site included a former sand and gravel borrow pit which the Arkansas Department of Pollution Control and Ecology (ADPC&E), the predecessor to ADEQ, subsequently approved for use as a landfill. Approximately 15,400 cubic yards of alum and lime electroplating sludge/slurry from the waste water treatment lagoons at Monroe's Paragould manufacturing plant were deposited in the borrow pit between 1973 and 1978. The sludge contained approximately 85% liquid. The dewatered weight of contaminated sludge was estimated to be 15,000 tons.

Initial Response

Under ADPC&E review, Monroe conducted a series of investigations at the site between 1979 and 1990. These included the installation of groundwater monitoring wells, and sampling and analysis of groundwater, soil, and surface water. The results of groundwater monitoring at the site in 1988 and 1989 indicated the presence of I 00 parts per billion (ppb) of 1, 1-Dichloroethane and 145 ppb of 1,2-Dichloroethylene. The site was proposed for listing on the National Priority List (NPL) as the Monroe Auto Equipment Co. (Paragould Pit) on October 26, 1989, (54 FR 43 778). The Site was listed final on the NPL as the "Monroe Auto Equipment Co. (Paragould Pit)" on August 30, 1990,(55 FR 35502). The primary contaminants identified by the EPA were solvents and degreasing agents including 1, 1-Dichloroethane (1 ,I-DCA), I ,2-Dichloroethene (1,2-DCE), Xylenes, and metals.

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Remedial Investigation and Feasibility Study (RI/FS)

A Potentially Responsible Party (PRP) search conducted in 1990 under CERCLA Section 104 (e) 42 U.S.C. 9604(e), indicated that Monroe Auto Equipment was the only PRP for the site. On March 14, 1991, the EPA issned notice of an impending Remedial Investigation and Feasibility Study (Rl/FS) to the PRP. Monroe Auto Equipment, now Tenneco, responded to the notice with a good faith offer to perform the RI/FS. On June 28, 1991, Monroe Auto Equipment Company entered into an Administrative Order on Consent with the EPA to conduct a RI/FS under CERCLA. The RI was completed in August 1993, and the FS was completed in April 1995. The RI/FS identified the types, quantities, and locations of contaminants found at the Site and developed ways to address the contamination. A Human Health Risk Assessment and an Ecological Risk Assessment were performed to determine the current and future effects of contaminants on human health and the environment.

Record of Decision Findings

The EPA and the ADEQ signed the ROD on September 26, 1996. The ROD selected remedy for the Site was comprised of two components, the initial Remedial Action (RA) and post-remedial monitoring. The initial RA consisted of capping the sludge disposal area and installing a groundwater interception system (French drain). The post remedial monitoring consisted of addressing the groundwater contamination through natural attenuation and monitoring. The ROD also required access and deed restrictions for the Site. In 1999, Tenneco submitted an Amended Plan for Soil Remedy. ADEQ submitted to EPA an Amended Proposed Plan of Remedial Action on January 10, 2000.

ROD Amendment

On November 9, 2000, the ROD remedy was amended to change the method of contaminated soil remediation. The original remedy required the containment of contaminated soils and sludge onsite. The Amendment changed the remedy to excavation and treatment of soils and sludge followed by offsite disposal in a permitted secure disposal facility as required by the Resource Conservation and Recovery Act.

Soil Remedial Implementation History

The RA was executed by the PRP in accordance with the ROD dated September 26, 1996, and the ROD Amendment dated November 9, 2000. The remedy for contaminated soils and sludge is comprised of two components, the initial RA and post-remedial monitoring. The RA consisted of excavation of the contaminated material, segregation of the stained soil from the contaminated sludge, treatment of the sludge, off-site disposal of the stained soil, and stockpiling of the treated sludge in a temporary on-site lined impoundment and ultimate disposal off-site. The RA was completed in the fall of 1999.

The final remedy is detailed in the following documents: Remedial Design Submittal Quality Assurance Project Plan, Remedial Action Workplan, Remedial Design Submittal Sampling and

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Analysis Plan (SAP), and Remedial Design Submittal Health and Safety Plan. The final remedy represents the culmination of activities that resulted from the preliminary site investigation completed in 1988, the RI/FS, the ROD and Amended ROD.

Overview of the Soil Remedial Action

The remedy is comprised of the following major components as stipulated in the Workplan:

• Excavate, segregate and stage sludge, stained soils, and overburden (clean soil) and unstained soils;

• Stockpile overburden and unstained soils for use as backfill;

• Stabilize sludge material with 5 to I 0 percent lime addition;

• Analyze stained soil and solidified sludge;

• Transport and dispose of stained soil that exhibits concentrations of constituents of concern (COC) below toxicity characteristic leaching procedure (TCLP) levels and EPA Region VI Medium Specific Health Based Screening Levels in a Subtitle D landfill;

• Stockpile stabilized sludge in an on-site lined containment cell;

·Apply for de-listing of stabilized sludge;

• Verify removal of impacted materials from the sludge pit through analytical testing of the bottom and sides of the excavation area;

• Restore the site by backfilling, grading and seeding;

• Transport and dispose of stabilized sludge in accordance with the results of the de­listing petition; and

• Conduct groundwater monitoring to ensure the effectiveness of the RA.

In order to achieve the RAOs, numerical risk-based cleanup levels were established for each environmental medium based on the residential scenario. A summary of the cleanup levels established in the ROD can be found in the appendix.

Summary of Soil RA Implementation

The soil remedial action consisted of the excavation and segregation of 14,633 cubic yards of soil and started in September 1999. Based on field calculations, a total of 3,348 cubic yards of overburden (clean fill material), 8,553 cubic yards of stained soil and 2, 732 yards of sludge (prior to stabilization and consolidation) were removed during the excavation activities.

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The overburden was removed, stockpiled, sampled and confirmed to meet the RA goals for soil and used as backfill. In accordance with the SAP, one grab sample was collected for every 2,000 cubic yards of overburden, unstained soil or clean backfill. A total of 8,160 cubic yards of additional soil was imported for use as backfill, yielding a total of II ,508 yards of backfill used to replace the stained soil and sludge removed from the site. The site was recontoured to provide better drainage, enabling use of a smaller amount of soil required for backfill (II ,508 cubic yards backfilled as compared to 14,633 cubic yards removed). A total of seven samples were collected from the overburden and imported backfill and confirmed the backfill material met the soil remedial clean-up requirements for the Site.

The 8,553 cubic yards of stained soil was stockpiled, sampled to confirm disposal in accordance with ADEQ requirements (Confirmation of Stained Soil Disposal Requirements, ADEQ October 27, 1999), and disposed in two Subtitle D Landfills upon confirmation of soil constituent levels. In accordance with the SAP, at a minimum, one grab sample was collected for every 500 cubic yards of stained soil. A total of 26 samples were collected from the stained soil to confirm this material met the disposal requirements for the permitted landfill. The weigh tickets from the SubtitleD Landfills confirm the disposal of the 8,553 cubic yards or 14,599 tons (1.7 tons I cubic yard) of stained soil as part of the Soil RA. A total of II ,621 tons of stained soil was transported and disposed at the Butler County Landfill in Poplar Bluff, Missouri and 2,978 tons of stained soil were transported and disposed at the Waste Management- Two Pines Landfill in Nmth Little Rock, Arkansas.

The 2, 732 cubic yards of sludge removed was stabilized with approximately 241 tons of quicklime and stockpiled in an on-site lined containment cell. In accordance with the SAP, at a minimum, one grab sample was collected for every 500 cubic yards of stabilized sludge. A total of seven samples were collected from the stabilized sludge to provide the basis for preparation of a petition for de-listing of this material. The 2, 723 cubic yards of sludge removed was based on field measurements prior to stabilization. Surveying of this material after stabilization and consolidation over several months after placement in the containment cell yielded a volume of 1,798 cubic yards. A De-listing Petition (Petition) was prepared by the PRP in August 2000. The Petition was approved by EPA and subsequently by the ADEQ in an August 27,2001, letter entitled Exclusion ofF006 Waste at the Tenneco/Monroe Facility from the Definition of Hazardous Waste. Upon approval of the Petition, the 1,798 cubic yards or 3,243 tons (1.8 tons I cubic yard) of stabilized sludge was transported and disposed of at the Waste Management- Two Pines Landfill in North Little Rock, Arkansas. The bottom and sidewalls of the sludge pit excavation were extended until the visually impacted material had been removed: Prior to the collection of verification samples, an additionall-foot of material was removed and disposed as stained soil. In accordance with the SAP, a verification soil sample was collected for every 500 square feet of sidewall or floor. A total of 81 verification samples were collected which confirmed that the excavation activities met the RA Goals for Soil at the site. In accordance with oral field instructions by the EPA Remedial Project Manager (RPM), and later included in the amendment to the ROD, the PRP excavated all of the stained soil and sludge until levels were at or below the RA Goals for Soil at the site. The stained soil that had concentrations of the COCs below the TCLP levels and the EPA Region 6's Medium Specific Health Based Screening Levels

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was excavated and disposed in a SubtitleD Landfill. The final shipment of stained soil was on December 16, 1999. The contractor also stabilized all of the contaminated soil and sludge which exhibited contaminant levels above the TCLP levels. The final shipment of the stabilized material was on September 13, 2001. The Groundwater Monitoring Plan, the Sampling and Analysis Plan, the Quality Assurance Project Plan, and the Operations and Maintenance Plan were developed in accordance with Section V of the Consent Administrative Order LIS 98-0 I 4 and the Statement of Work that had been issued for the post-soil remediation groundwater remedy. Construction-related activities were completed and the final inspection was conducted on September 14,2001. The Preliminary Close Out Report was signed on September 19,2001.

Groundwater Remedial Implementation History

Natural attenuation and monitoring was the remedy selected in the ROD to address the groundwater contamination on and offsite. The ROD amendment did not change the groundwater remedy. The ROD required the PRP to develop a Groundwater Monitoring Plan (GMP) and beginning in September 2001, semiannual monitoring of 18 wells. The PRP conducted groundwater monitoring events through March 2009.

III. MONITORING RESULTS

The Final Remedial Action Report documents the results of sampling of waste removed from the Site. The sample results demonstrate that the Remedial Action Objectives were met for the soil remedy. The PRP was also required by the ROD to develop a Groundwater Monitoring Plan to monitor the effectiveness of the Remedial Action. The results of groundwater sampling at the site demonstrate attainment of the groundwater remedy.

IV. ATTAINMENT OF GROUNDWATER RESTORATION CLEANUP LEVELS

The Groundwater Remedy portion of the September 26, 1996, ROD and the 2000 ROD Amendment included conducting long-term groundwater monitoring of wells at the Site and local private wells located in the vicinity of the Site. As part of the Groundwater Remedy, a Groundwater Monitoring Plan (GMP) was prepared for the Site. The GMP was developed in accordance with Section V of the CAO LIS 98-014 and the SOW issued for the post-soil remediation Groundwater Remedy. The GMP specified procedures to be followed for long-term groundwater monitoring to ensure compliance with the requirements of the CAO, the ROD, and the ROD Amendment. Tenneco initiated GMP activities in September 2001 and has continued to conduct semi-annual/annualmonitoring of the groundwater wells at the site as outlined in the GMP.

Based on analysis of semi-annual groundwater sampling results since March 2001, a request was made and approved to reduce the number of groundwater monitoring wells and COCs included in the Site GMP. The requested revised GMP focused only on volatile organic chemicals (VOCs) at six select groundwater monitoring well locations. A request to remove the requirements for sampling of the private wells was submitted to EPA and ADEQ on March 31, 2002. The request was approved following submittal of the Private Well Report (2004). The

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Private Well Report provided a summary of available information for each of the twenty-nine (29) wells and presented a comparative analysis of the analytical results from over ten (l 0) years of sampling the private wells relative to the maximum contaminant levels (MCLs). Based on the findings presented in the report, no VOCs were detected in any of the private wells above the MCLs over the past ten (l 0) years. Select inorganics, primarily lead, were detected at varying concentrations, periodically exceeding the respective MCL in select samples collected prior to 1996. These detections of lead however were within background concentration levels for the surrounding area and not believed to have resulted from contamination at the site. Based on the data review presented in the Private Well Report, none of the private wells located within one­half mile of the site have been impacted by contamination from the site:

The results of the semi-annual/annual sampling events are presented in respective Semi­Annual/ Annual Sampling Reports. Based on the most recent groundwater sampling results from the site groundwater monitoring wells, presented in the March 2009 Comprehensive Summary Report Annual Groundwater Sampling Event for the Monroe Superfund Site, the levels of COCs attenuated sharply after source removal and have continued to decrease. COCs have remained below their respective clean up criterion as stated in the ROD since July 2003.

The concentrations of COCs continue to remain below the remedial goals for the Site in all of the groundwater monitoring wells sampled with the approved groundwater monitoring program. The concentrations in all of the Site groundwater monitoring wells have continued to exhibit concentrations of VOCs below the remedial goals established in the ROD over the past eight semi-annual and two annual sampling events. The results of the groundwater monitoring since July 2003 confirm the effectiveness of the completed soil remedy and removal of the former source of groundwater contamination. Table 2 of the appendix presents groundwater monitoring data from the 2009 annual report that demonstrates site RA goals for groundwater are maintained through natural degradation and attenuation.

V. SUMMARY OF OPERATION & MAINTENANCE REQUIRED

The ROD specified monitored natural attenuation as the remedy for ground water remediation based on implementation of a containment onsite of contaminated soils. The soil remedy was modified in the ROD Amendment to include removal of stained soil and sludge from the site to below the Site RA Goals for Soil. The results of groundwater monitoring since removal of the stained soil and sludge demonstrate that the natural attenuation remedy was. effective and that the remedial goals for the groundwater as stated in the ROD have been achieved. Groundwater monitoring at the Site was discontinued after the Second Five Year Review in 2009. The monitoring wells were properly plugged and abandoned in 2010. There are no operation and maintenance activities required at the Site.

Institutional Controls

A deed notice/covenant identifying restrictions on the Site was filed with the Greene County Clerk in November 2003. The covenant prohibited the installation of any private, commercial, industrial or other water well or other device for the removal or extraction of subsurface water.

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The only ground water allowed to be extracted from beneath the property is for the purpose or purposes associated with environmental sampling and testing of the groundwater. The RA goals for the groundwater have been met and the monitor wells have been removed. Since the soil cleanup and backfill materials met residential reuse scenarios, no restrictions on the use or sale of the property are necessary and the existing land use restrictions may be removed.

VI. DEMONSTRATION OF CLEANUP ACTIVITY QA/QC

The EPA and ADEQ reviewed the remedial action report and the construction work for compliance with quality assurance and quality control (QA/QC) protocols. Construction activities at the Site were determined to be consistent with the ROD and ROD Amendment and adhered to the approved quality assurance plan which incorporated all EPA and State reqlJirements. Confirmatory inspections, independent testing, audits, and evaluations of materials and workmanship were performed in accordance with the technical specifications and plans. The EPA Remedial Project Manager and State regulators visited the site during construction activities to review construction progress and evaluate and review the results of QA/QC activities. No deviations or non-adherence to QA/QC protocols, or specifications were identified.

The quality assura.nce project plan incorporated all EPA and State QA/QC procedures and protocols. All monitoring equipment was calibrated and operated in accordance with the manufacturer's instructions. The EPA analytical methods were used for all confirmation and monitoring samples during RA activities. Contract laboratory program-like procedures and protocol were followed for soil, sediments, and water analyses during the RA using a private laboratory.

The Remedial Design contained provisions for performing sampling during all remedial activities in order to verify that remedial objectives were met, to ensure quality control and assurance for all excavation and construction activity, and to ensure protection and safety of the public, the environment, and the onsite worker. Sampling was conducted in accordance with the Site Field Sampling Plan and all analytical results are below the established cleanup levels for a residential reuse scenario. In addition, all backfill confirmation sample results met the established cleanup levels for a residential reuse scenario. All analytical data was independently validated, and the EPA and the State determined that analytical results were accurate to the degree needed to assure satisfactory execution of the RA.

VII. FIVE-YEAR REVIEW

Five-Year Reviews were statutorily required because hazardous substances, pollutants, or contaminants remained at the Site above levels that allow for unlimited use and unrestricted exposure. There have been two five-year reviews conducted at the Site, with the last one in 2009. The United States Environmental Protection Agency (EPA) Region 6 and the ADEQ conducted the second five-year review for the response action implemented at the Monroe Auto Pit Superfund Site. Also participating in the five-year inspection were representatives of Tenneco.

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The 2009 Five Year Review found that all hazardous substances in the groundwater had naturally attenuated at the Site below clean up levels. The remedial action of natural attenuation for the groundwater is completed and no hazardous substances, pollutants or contaminants remain above levels that could prevent unlimited use and unrestricted exposure. Per the 2009 Five Year Review, unlimited use and unrestricted exposure has been achieved: therefore, · additional Five Year Reviews will not be required for the Site.

VIII. SITE COMPLETION CRITERIA

The implemented remedy achieves the degree of cleanup or protection specified in the 1996 ROD and the 2001 ROD Amendment for all pathways of exposure. All selected remedial action objectives and associated cleanup goals are consistent with agency policy and guidance. This Site meets all the site completion requirements as specified in OSWER Directive 9320.2-22, Close-Out Procedures for National Priorities List Sites. All remedial activities at the Monroe Auto Equipment Superfund Site are complete and the Site poses no unacceptable risk to human health or the environment. Therefore, EPA has determined that no further response is necessary at the Monroe Auto Equipment Superfund Site.

Carl Edlund,

Director Superfund Division

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IX. BIBLIOGRAPHY

Record of Decision, Monroe Auto Equipment Company Superfund Site, Paragould, Arkansas, ARD98086411 0, September 26, 1996.

Record of Decision Amendment, Monroe Auto Equipment Company Superfund Site, Paragould, Arkansas, ARD980864110, November 9, 2000.

Preliminary Close Out Report, Monroe Auto Equipment Company Superfund Site, Paragould, Arkansas, ARD98086411 0, September 17, 200 I.

Final Remedial Action Report (Construction Completion Report) for Monroe Auto Equipment Company Superfund Site, Paragould, Arkansas, ARD98086411 0, August 21, 200 I.

Second Five-Year Review Report for Monroe Auto Equipment Company Superfund Site, Paragould, Arkansas, ARD980864110, August 13,2009.

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APPENDIX

Figure I - Site Location Map

Table I - Summary of RA Goals

Table 2- Historical Groundwater Analytical Results

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Figure 1 Site Location Map

0

Monroe _...._ Auto Pit

0

IJ 0 0 0

D Residences

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Soil/Sludge

Contaminant of Concern Trichloroethylene Vinyl chloride Antimony Arsenic Beryllium Chromium VI Lead

Groundwater

Contaminant of Concern cis-! ,2-Dichloroethylene trans-1 ,2-Dichloroethylene bi s(2-Eth y lhexy 1 )phthalate Beryllium Chromium Lead Manganese

Table 1 Summary ofRA Goals

Target Goal 0.1-10 mg/Kg 20-2,000 mg/Kg 6 mg/Kg 0.02-2 mg/Kg 0.07-7 mg/Kg 3-300 mg/Kg 500 mg/Kg

Target Goal 70 mg/L 100 ug/L 6 ug/L 4 mg/L 50 mg/L 15 ug/L 200 mg/L

15

Basis Carcinogenic Risk Carcinogenic Risk Non-Carcinogenic Effects Carcinogenic Risk Carcinogenic Risk Carcinogenic Risk EPA Guidance

Basis MCL MCL MCL MCL MCL SDW A Action Level MCL

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~-------- --~·-----

Table 2 Historical Groundwater Analytical Results for Select Monitoring Wells

At Monroe Auto Pit Superfund Site (Finch Road) ··----~··--

Year 1988 ---Quarter March

,---~----- ---- ---------·---~----··-· ·-·--------~---- --~···---···-·-····-- ··--·---- ... ·----·--·-~---

cis trans cis trans TCE 1,1 DCA 1,2DCE 1,2 DCE TCE 1,1 DCA 1,2 DCE 1,2 DCE

Constituent ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone -------- -~---,-------- --------ESW-2A <5 --- 97- 750 <5 <10 20 94 <10 ESW-3A <5 6 7.8 <5 <10 <10 17 <10

- -------- ··-- --ESW-11-1 NS NS NS NS <10 <10 <10 <10

------.--~ -------------- -- ---···--- -·-·· ··-·--· --- --------------ESW-11-3 NS NS NS NS <10 <10 <10 <10 ESW-12-1 NS NS NS NS <10 <10 <10 <10 ESW-12-3 NS NS NS NS <10 <10 --- <10 <10 .... ···-ESW-14-1 NS NS NS NS <10 <10 <10 <10 --·----- --ESW-14-3 NS NS NS NS <10 <10 18 <10

Year 2001

Quarter March September --r-------'c~ ------ ----cis trans cis trans

TCE 1,1 DCA 1,2 DCE 1,2 DCE TCE 1,1 DCA 1,2DCE. 1,2DCE Constituent ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone ESW-2A <5 28 110 <5 <5 35 190 <5 ESW-3A <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-3 5.9 <2 <5 <5 <5 <2 <5 <5 ESW-12-1 6.2 <2 <5 <5 <5 <2 <5 <5 ESW-12-3 15 <2 <5 <5 <5 <2 <5 <5 ESW-14-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-14-3 <5 4A IS <5 <5 3.7 15 <5

Year ~02 --Qumter May October - ,---

cis trans cis trans TCE 1,1 DCA 1,2 DCE 1,2DCE TCE 1,1 DCA 1,2 DCE 1,2 DCE

Constituent ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone ESW-2A <5 31 180 <5 <5 26 130 <5 ESW-3A <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-3 <5 <2 <5 <5 <5 <2 <5 <5

E-SW-12~1 -

<5 <2 <5 <5 <5 <2 <5 <5 ESW-12-3 <5 <2 <5 <5 <5 <2 <5 <5 ----ESW-14-1 <5 4A 14 <5 <5 <5 <5 <5 ESW-14-3 <5 <2 <5 <5 <5 3.9 14 <5

-····-········-···-·····

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··---·--· ·········-····~-·----··-··-·~····--·

Year 2003 2004 --Quarter July March ...

CIS trans cis trans TCE l,l DCA l,2DCE l,2DCE TCE l,l DCA 1,2 DCE l,2DCE

Constituent ugll ~ ug/1 ug/1 ug/1 ug/1 ug/1 ug/l

Wilcox Aquifer Upper Zone ESW-2A <5 17 66 <5 <5 14 44 <5 ESW-3A <5 <2 <5 <5 <5 <2 6.2 <5 ESW-1 1-1 <5 <2 <5 <5 <5 <2 <5 <5 ..

ESW-1 1-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-12-1 <5 <2 <5 <5 <5 <2 <5 <5 -- •.. ESW-12-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-14-1 <5 <5 <5 <5 <5 <2 <5 <5

-· ESW-14-3 ~- . <5 <5 18__ <5 <5 2.5 9.5 <5

Year 2004 2005

Quarter October May

cis trans CIS trans TCE 1,1 DCA 1,2DCE 1,2 DCE TCE 1,1 DCA 1,2 DCE 1,2 DCE

Constituent ug/1 ug/1 ug/1 uo/l ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone ESW-2A <5 14 38 <5 <5 16 14 <5 ESW-3A <5 2.6 9.6 <5 <5 2.9 I I <5 ESW-1 J.J <5 <2 <5 <5 <5 <2 <5 <5

··-ESW-1 1-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-12-l <5 <2 <5 <5 <5 <2 <5 <5

---··- ·----------ESW-12-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-14-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-14-3 <5 <2 7.2 <5 <5 2.3 6.4 <5

··-··-

Year 2005 2006 ---· ··-

Quarter October A ril

cis trans cis trans TCE 1,1 DCA 1,2 DCE 1,2DCE TCE 1,1 DCA l,2DCE 1,2 DCE

Constituent ~ ug/1 ug/l ug/1 ug/1 ug/l ug/l ug/l

Wilcox Aquifer Upper Zone

~:2A <5 12 37 <5 <5 13 44 <5 ESW-3A <5 2 8.2 <5 <5 2.2 6.8 <5 ---·· ESW-1 J.J <5 <2 <5 <5 <5 <2 <5 <5 ESW-1 1-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-12-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-12-3 <5 <2 <5 <5 <5 <2 <5 <5

--·--·--· ....

ESW-14-1 <5 <2 <5 <5 <5 <2 <5 <5 ...

ESW-14-3 <5 <2 6.6 <5 <5 2.2 6.6 <5 --·-· ··-·-····- __ .. ____

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··-·--·--·- ····-~-~----~~-···--··---··~-·-

Year 2006 2007

Quarter November Mav ··-···--

cis trans cis trans TCE 1,1 DCA 1,2 DCE 1,2 DCE TCE 1,1 DCA 1,2 DCE 1,2DCE

Constituent ug/1 __tJ_g!i__ ug/1 ug/1 ug/1 ug/1 u;;/1 ug/1

Wilcox Aquifer Upper Zone -~-2A_ <5 14 52 <5 <5 14 62 <5

--·-··---~~-- ~~-·-··---~·-···- ---~------- -··-·-··----··~· --- -···-·-ESW-3A <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-1 <5 <2 <5 <5 <5 <2 <5 <5 ESW-11-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-12-1 <5 <2 <5 <5 <5 <2 <5 <5

--·-····· ESW-12-3 <5 <2 <5 <5 <5 <2 <5 <5 ESW-14-1 <5 <2 <5 <5 <5 <2 <5 <5

-···-· ESW-14-3 <5 2.5 6.4 <5 <5 <2 <5 <5

Year 2008 ···-····-··--···- -

_Q~.mier A ril April ADEQ

cis trans cis trans TCE 1,1 DCA 1,2DCE 1,2DCE TCE 1,1 DCA 1,2DCE !,2DCE

Constituent ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone ESW-2A <5 13 56 <5 0.672 12 52.6 <0.590 ESW-3A <5 <2 <5 <5 0.622 0.523 0.82 <0.590 ESW-ll-1 <5 <2 <5 <5 <0.600 <0.420 0.869 <0.590 ESW-ll-3 <5 <2 <5 <5 0.77 <0.420 <0.770 <0.590 ESW-!2-1 <5 <2 <5 <5 <0.600 0.679 2.9! <0.590 ESW-!2-3 <5 <2 <5 <5 <0.600 0.526 !.39 <0.590 ESW-!4-1 <5 <2 <5 <5 <0.600 <0.420 <0.770 <0.590 ESW-!4-J-

----- ... ···~·-··---~ ---·-·-··-··· <5 <2 <5 <5 <0.600 !.78 3.69 <0.590 ..

Year 2009

Quarter March 1--~' a--- -

ci trans CIS trans TCE !,! DCA !,2 D !,2 DCE TCE 1,! DCA !,2DCE !,2 DCE

Constituent ug/l ug/l ug/ ug/1 · ug/1 ug/1 ug/1 ug/1

Wilcox Aquifer Upper Zone ESW-2A <5 !2 42 <5 ESW-3A <5 <2 <5 <5 ESW-1!-1 <5 <2 <5 <5 ESW-1!-3 <5 <2 <5 <5

·-·-· ESW-12-1 <5 <2 <5 <5 - - ·-·· ---······- ---····--·-···· ESW-12-3 <5 <2 <5 <5 ESW-14-1 <5 <2 <5 <5

--·· ESW-!4-3 <5 2.2 5.2 <5

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