D () Stantec

LNAPL RECOVERY, TRANSMISSIVITY, AND NSZD WORK PLAN

Former Coastal Refinery

El Dorado, Kansas

November 2018

Prepared for:

El Paso Merchant Energy­Petroleum Company Colorado Springs, CO

Prepared by:

c 2 ... oog- 1o z~-J3- 8 .. 1

Stantec Consulting Services, Inc. 8200 E 34th Street Circle North, Suite 1201 Wichita, Kansas 67226

This doc ument entitled LNAPL Recovery, Transmissivity, and NSZD Work Plan was prepared by Stantec

Consulting Servic es Inc. ("Stantec") for the account of Kinder Morgan (the "Client" ). Any reliance on this

document by any third party is strictly prohibited. The material in it reflects Stantec 's professional judgment

in light of the scope, schedule and other limitations stated in the document and in the contract between

Stantec and the Client. The opinions in the document are based on conditions and information existing at

the time the document was published and do not take into account any subsequent changes. In

preparing the document, Stantec did not verify information supplied to it by others. Any use which a third

party makes of this document is the responsibility of such third party. Such third party agrees that Stantec

shall not be responsible for costs or damages of any kind, if any, suffered by it or any other third party as a

result of decisions made or actions taken based on this document.

(signature)

Jeffrey D. TeGrotenhuis, P.E.

Reviewed by_a--+~f---i!n_r+ __ _ (signature)

Cristy H. Philips, P.G.

Approved by --~....,.9-'------C_. -~--~"----------(signature)

Jason C . Garnsey, P.G.

TABLE OF CONTENTS

ES EXECUTIVE SUMMARY

1.0 INTRODUCTION ....................................................... .................................................. ..... 1-1

1 .1 Site Description .. ........................................................................................... ........ 1-1

1 .2 Site History ............................................ ..... ......................... ........ ........ .... ..... .. ......... 1-1 1 .3 Groundwater Flow .................... .... ....................... ............ .. .. ................ ................. 1-2

1.4 Free and trapped LNAPL Extent ................................ .... .... ... ..... ......................... 1-2

1.5 Interim Remedial Measures (IRM) .............. ..... .................................................... 1-2

1.5.1 Seep Interceptor Trenches ........ .... ......................................................... 1-3

1.5.2 MPA Channel and Basin Interceptor Trench ...... ......... ... ...................... 1-3

1 .5.3 MP A Spring System .......... ......................... .... ...... ... .. .. .. ..... ...... ..... .. .......... 1-4

1 .5.4 AHA Pit Excavation ............................... ................. ........ .. ........... ............ 1-4

2.0 LNAPL CONCEPTUAL SITE MODEL (CSM) ..................................................................... 2-1

2.1 MPA ........... .... .. ... .... ... .... .... ................ ......... ............................................. ............... 2-1

2.2 AHA ..... .. .... .... ....... ............... ................ ................................................................... 2-1

2.3 STF ................... .................... ......... ...... ..................................................................... 2-1

2.4 SPA .. ............................. .. ... ......................... .. .................. ... ..... .... ..... .. .. .... .. ... .. .. ... ... 2-2

3.0 FREE PHASE LNAPL RECOVERY ...................................................................................... 3-1

3.1 Continued IT System Operation .. ..... .. ................................................................. 3-1

3.1.1 Operation and Maintenance (O&M) Period ...................... .... ...... ....... 3-1

3.1.2 O&M Procedures ..................................................... ... .. .... .. .................. .. . 3-1

3.2 Continued MPA Spring System Operation ......................... .. ....... .. .... ..... ............ 3-2 3.2.1 O&M Period ............................................................... .................... .......... 3-2 3.2.2 O&M Procedures ................. ......... ........ .......... ............................. .... ... ... .. 3-2

3.3 Additional Product Recovery ........................ ... .. ..................... ......... ..... .............. 3-3

3.3. 1 Wells in Program .................................................................... .......... ..... .. . 3-3 3.3.2 O&M Frequency and Duration ............................................................. . 3-3

3.3.3 O&M Procedures .. ......... ................................................................. ........ . 3-3 3.3.4 Waste Management ............................................................................. . 3-4

4.0 LNAPL TRANSMISSIVITY TESTING ............................................................ ...................... . 4-1

4.1 Frequency and Number ................................................................. .......... ... ...... .. 4-1

4.1 .1 MPA Spring and ITs .... ....................... .. ....... ......................................... ... . .4-1

4.1.2 Monitoring Wells ................................................................................ ..... .4-1

4.1 .3 Minimum Test Thicknesses/Recoverable Product ......................... ...... .4-2

4.2 Methods ................................................................................................................. 4-2

4.2.1 Bail-down/Slug Test (ASTM E2856 Sections 5.2 and 6.1) ..... .. ...... ........ .4-2 4.2.2 Manual LNAPL Skimming Test (ASTM E2856 Sections 5.3 and 6.2) .... .4-3 4.2.3 Recovery Data-Based Methods (ASTM E2856 Sections 5.4 and 6.3) .4-3 4.2.4 Tracer-Based Methods (ASTM E2856 Sections 5.5 and 7.0) .... .. ......... .4-4

5.0 NATURAL SOURCE ZONE DEPLETION (NSZD} ................................................................ S-1

5.1 NSZD Measurement Methods ............................................................. ................. 5-2 5.1.1 Step 1 - C02 Efflux Measurement .......................................... ................ 5-2 5.1.2 Step 2- Background Correction of Total C02 Efflux Measurements .5-5 5.1.3 Step 3- Stoichiometric Conversion of C02 Efflux to an NSZD Rate .... 5-6

5.2 NSZD Assesment Work Plan .................................................................................. 5-7 5.2.1 Initial Verification and Quantification of NSZD .. ... .... ............................ 5-8 5.2.2 Long-term NSZD Monitoring .................................. .......................... ... .. 5-11

6.0 REFERENCES ................................................................................................................... 6-1

Table 3-1

Figure 1-1 Figure 1-2 Figure 1-3 Figure 1-4 Figure 1-5 Figure 1-6 Figure 1-7 Figure 1-8 Figure 1-9 Figure 1-10 Figure 1-11 Figure 5-1 Figure 5-2 Figure 5-3 Figure 5-4 Figure 5-5

LIST OF TABLES

Product/LNAPL Thickness

LIST OF FIGURES

Site Location Map Site Plan and Areas of Concern (AOC) Potentiometric Surface Map- October 2, 2013 Potentiometric Surface Map- November 9, 2015 LNAPL Isopach Map February 2009 LNAPL Isopach Map October 2013 LNAPL Isopach Map November 2017 Soil Headspace Gas Data, 0-32' Composite, Northern Area Soil Headspace Gas Data, 0-32' Composite, Southern Area Existing and Preferred Alternative Interceptor Locations MPA Spring Collection and Treatment System Vapor Transport Related Processes at Petroleum Release Sites LI-COR® 81 OOA DCC Apparatus and Setup Example Output from a C02 Efflux Measurement Using the LI-COR® 81 OOA E-Fiux Passive Flux Trap Apparatus and Setup Proposed C02 Efflux Monitoring Locations

LIST OF APPENDICES

Appendix A LNAPL Skimmer Equipment Cut Sheets Appendix B LI-COR® C02 Efflux Survey Procedures Appendix C E-Fiux C02 Trap Procedures

AHA AST ASTM BER bgs BOW CAD CAG CAS EPME-PC ES ft2/day Fino FML gpm GTS HDPE HF IRM IT KDHE LNAPL MNA MPA MWH NGVD NPDES NSZD O&M ows Pester PID PSB ROSE STF TPH uows WBWR

LIST OF ACRONYMS AND ABBREVIATIONS

Asphalt Handling Area Aboveground storage tank American Society for Testing and Materials Bureau of Environmental Remediation Below ground surface Bureau of Water Corrective Action Decision Corrective Action Goal Corrective Action Study El Paso Merchant Energy-Petroleum Company Extraction sump Square feet per day American Petrofina Oil and Chemical Company Flexible membrane liner Gallons per minute Groundwater Treatment System High-density polyethylene Hydrofluoric Interim remedial measures Interceptor Trench Kansas Department of Health and Environment Light non-aqueous phase liquid Monitored natural attenuation Main Process Area MWH Americas, Inc National Geodetic Vertical Datum National Pollutant Discharge Elimination System Natural source zone depletion Operation and maintenance Oil-water separator Pester Refining Company Photoionization detector Precipitation/Settling Basin Residual Oil Supercritical Extraction South Tank Farm Total petroleum hydrocarbons Underground oil-water separator West Branch Walnut River

EXECUTIVE SUMMARY

This document presents a comprehensive long-term plan to address petroleum-related light non-aqueous phase liquid (LNAPL) at the former Coastal Refinery (Site) located north of the City of El Dorado, Kansas. The Site is currently owned by El Paso Merchant Energy­Petroleum Company (EPME-PC). This work plan includes: 1) product recovery; 2) LNAPL transmissivity testing to assess when recovery is no longer warranted; and 3) natural source zone depletion (NSZD) to estimate the amount of petroleum mass being degraded through natural processes. This work is in accordance with Corrective Action Study (CAS, MHW 2014) corrective action goals (CAGs); the Corrective Action Decision (CAD, Kansas Department of Health and Environment [KDHE], 2016) requirements; and the July 2018 Consent Order Amendment.

PRODUCT RECOVERY

Product recovery will continue through operation of the existing site interceptor trenches (ITs): Seep IT, Main Process Area (MPA) Channel IT, and MPA Basin IT. This includes groundwater depression and treatment through a wetlands-based system. Product recovery also occurs through the gravity-flow MPA Spring interceptor and treatment system. LNAPL skimmers will be used in monitoring wells as appropriate; however, given the low current thicknesses, it is likely most monitoring well-based product recovery will be through hand bailing and sorbent socks.

TRANSMISSIVTY TESTING

Monitoring well-based product recovery and IT groundwater and product recovery will continue until the LNAPL transmissivity in each monitoring well upgradient of the trenches and in each trench are confirmed to be below a transmissivity of 0.8 ft2/day as discussed in the September 1, 2015 KDHE TPH and LNAPL Characterization, Remediation, and Management Policy (BER-041 ). IT operation may continue beyond this determination for other reasons, such as groundwater containment. Transmissivity testing will be completed in accordance with the procedure detailed in the American Society for Testing and Materials (ASTM) standard E2856-11 , Standard Guide for Estimation of LNAPL Transmissivity.

NATURAL SOURCE ZONE DEPLETION (NSZD)

NSZD is a combination of natural-occurring subsurface processes that solubilize and volatilize LNAPL components and biologically break them down over time; NSZD is recognized as a remediation technology that biologically converts LNAPL into innocuous aqueous and gaseous by-products (ITRC, 2009) . The presence and rate of NSZD has not been confirmed at the Site; hence, the adequacy of these processes to achieve CAGs

is not verified. However, experience at other petroleum-impacted sites confirms that not only are these natural attenuation processes nearly always present. but they also typically result in significant LNAPL mass destruction (Lundegard and Johnson, 2006: Sihota et al., 2011: McCoy et al., 2015; and Palaia, 2016) . To demonstrate the effectiveness of NSZD at the Site, it will be quantified to establish rates of source mass loss and verify its prominent role in site remediation. A dynamic closed chamber (DCC) and passive flux traps will be used to estimate NSZD rates by stoichiometric conversion of C02 efflux measured at ground surface. After the mass loss rates are initially verified , NSZD rates will be monitored every five to ten years to evaluate its performance and document its sustainability. The results of NSZD monitoring will be also used to aid in making decisions of when active remediation is no longer necessary and/or sufficiently beneficial to continue.

1.0 INTRODUCTION

This document presents the long-term plan to address petroleum-related light non­aqueous phase liquid (LNAPL) at the former Coastal Refinery located north of the City of ElDorado, Kansas (Site) , which is currently owned by El Paso Merchant Energy-Petroleum Company (EPME-PC) . Plan components include 1) active and passive product recovery; 2) LNAPL transmissivity testing to assess when recovery is no longer warranted; and 3) natural source zone depletion (NSZD) evaluations to estimate the amount of petroleum mass being degraded through natural processes. This work is in accordance with Corrective Action Study (CAS, MHW 2014) corrective action goals (CAGs) of addressing practically recoverable product; the Corrective Action Decision (CAD, Kansas Department of Health and Environment [KDHE]. 2016) requirements; and the July 2018 Consent Order Amendment.

1.1 SITE DESCRIPTION

The former Coastal Refinery is located north of the City of El Dorado, Kansas in portions of Sections 26, 27, 34, and 35, Township 25 South, Range 5 East. Butler County, Kansas as shown in Figure 1-1 . The Site includes 1) a former process area for the refinery, referred to herein as the Main Process Area (MPA) ; 2) vacant property to the west. referred to herein as the Asphalt Handling Area (AHA) ; 3) the former tank farm located due south of the refinery, referred to herein as the South Tank Farm (STF) ; and 4) water treatment wetlands ponds (former wastewater/stormwater) to the east. referred to as the Stormwater Pond Area (SPA). as shown in Figure 1-2. The West Branch Walnut River (WBWR) defines the northeastern boundary of the Site. The Site does not include the adjacent Pester Refining Company (Pester) Burn Pond Superfund site, which is located north of the SPA.

1.2 SITE HISTORY

The refinery was constructed in 1917 for the Pester Refining Company (Pester). Petro Atlas purchased the refinery in 1958, and within six months, sold the refinery to American Petrofina Oil and Chemical Company (Fino) . Fino owned the refinery and surrounding property between 1958 and 1977. In 1977, Pester purchased the property from Fino and continued to operate the refinery until filing Chapter 11 bankruptcy on February 25, 1985. The crude unit and most of the other operational units were shut down in March 1985.

On April 10, 1986, Coastal Refining Company purchased the land and equipment at the refinery from Pester, excluding the Burn Pond . At that time, the major process units at the refinery included crude oil distillation, hydrodesulfurization, catalytic reforming, fluid catalytic cracking, hydrofluoric (HF) alkylation, and Residual Oil Supercritical Extraction (ROSE).

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The refinery produced regular and unleaded gasoline, #2 fuel oil. #6 fuel oil. propane, and asphalt. An asphalt blending facility was operated at the Site until September 2004.

1.3 GROUNDWATER FLOW

Groundwater flow controls the direction and rate of potential LNAPL migration. The unconfined shallow groundwater-bearing zone occurs within alluvium. weathered/fractured Doyle Shale and the Fort Riley Limestone and is collectively referred to as the Shallow System. As with most of the Site , the vast majority of groundwater flow occurs through several feet of weathered limestone immediately above the Fort Riley competent bedrock. Natural groundwater flow is generally east toward the river (WBWR); however. the Interim Remedial Measures (IRM) MPA Basin groundwater interceptor trench (IT) operation and Seep IT have shifted the groundwater flow direction more toward the southeast corner of the MPA as shown in Figure 1-3 (October 20 13) and Figure 1-4 (November 2015). In the northern portion of the STF, groundwater flow is east to northeast because of a bedrock channel and the influence of the MPA Basin IT pumping. In the middle of the STF, groundwater flow is southeast toward the STF Creek. Groundwater south of the STF Creek is flowing north-northeast toward STF Creek

1.4 FREE AND TRAPPED LNAPL EXTENT

The extent of free phase LNAPL has declined over the years, likely as a result of NSZD (discussed in detail in Section 5) and active product recovery efforts, including the MPA Basin IT and Seep IT. Figure 1-5 (February 2009), Figure 1-6 (October 2013), and Figure 1-7 (November 2017) show the change in LNAPL extent over time. The residual areas are the focus of the proposed free-phase recovery efforts and transmissivity evaluation.

LNAPL trapped within or sorbed to the soil matrix is present over a larger area. Soil analytical data are available; however. vertically average field photoionization detector (PID) readings provide better delineation for contouring purposes, which are shown on Figures 1-8 and Figure 1-9. These areas, which include the free-phase LNAPL, are the focus of the proposed NSZD study.

1.5 INTERIM REMEDIAL MEASURES (IRM)

From 2006 through 2012, EPME-PC performed a series of IRMs to prevent seep impacts to the river and to facilitate closure of the Site's wastewater treatment ponds by December 31, 2012. The wastewater treatment pond closure date was required by the KDH E-Bureau of Water (BOW) as set forth in the National Pollutant Discharge Elimination System (NPDES) Permit conditions for the Site. Only aspects of the IRMs that are ongoing and are part o f the Site LNAPL strategy are summarized below for reference. Extracted groundwater and product are treated through an oil-water separator (OWS) and wetlands-based system.

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1.5.1 Seep Interceptor Trenches

The first IRM was the installation of a 1 ,650-foot Seep IT located immediately upgradient of and paralleling the WBWR as shown in Figure 1-10. This trench was installed to prevent petroleum-impacted groundwater and product from seeping into the WBWR. The Seep Interceptor Trench Final Design was completed in March 2006. Construction began that summer with the continuous trench being excavated with a hydraulic excavator through the weathered bedrock until refusal. An effort was made to remove all weathered rock possible, including use a bucket equipped with rock teeth. The final bottom of the fractured bedrock surface undulated across the 1 ,650-foot long trench. Three extraction sumps (ESs) were installed in the low points along this trench with gravel extending up to above the highest known groundwater elevations. Ten-foot deep screened sumps were drilled at each ES location into the weathered bedrock to place the groundwater extraction pump and floats below the bottom of the trench, maximizing dewatering.

The Seep IT began operation in December 2006. Little to no free-phase LNAPL has been recovered to date, suggesting little to no additional free product migration toward the river is occurring. Groundwater contours imply capture of most to all of the groundwater entering the trench system as shown in Figure 1-4. A surface water sampling program has confirmed no detectable impact on water quality from the Site.

1.5.2 MPA Channel and Basin Interceptor Trench

The MPA Basin and MPA Channel were installed for Site stormwater management with construction beginning in October 2010 and ending in January 2011.

1.5.2.1 MPA Basin IT. A groundwater and LNAPL interceptor trench (Basin IT) was excavated at the bottom of the MPA Basin to collect product and impacted groundwater as shown in Figure 1-10. The Basin IT was extended through upper weathered bedrock until solid bedrock was encountered. A perforated pipe was placed in the bottom, the trench was filled with gravel, and the entire MP A Basin was lined with a 60-mil high-density polyethylene (HDPE) textured flexible membrane liner (FML) to separate the groundwater and stormwater systems within the MPA Basin. A separate sump, pump, and conveyance lines are used to pump extracted water and product to the water treatment system. Approximately 875 gallons of LNAPL have been recovered since the Basin IT began operating in December 2011.

1.5.2.2 MPA Channel IT. Groundwater seeps (some containing LNAPL) were exposed along the southern half of the MPA channel ; therefore, a narrow 1 ,200-foot long trench was excavated as deep into the weathered bedrock as possible, as shown in Figure 1-10. A perforated pipe was installed in the bottom to gravity drain into the MPA Basin IT and the trench was filled with gravel and covered with an impermeable membrane. This was then covered with concrete fines and riprap to create the stormwater channel. The

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resulting MPA Channel IT protects surface water quality while enhancing recovery of shallow groundwater perched within the abundant concrete sand bedding that remains from the former refinery structures.

1.5.3 MPA Spring System

The MPA Spring is located in the central portion of the MPA and is believed to have been created when a catalytic cracking unit footing was installed through weathered bedrock many years ago. Flow is present throughout much of the year varying from no flow during dry summer and winter months to over 60 gallons per minute (gpm) during wet periods. Historically, water discharging from the MPA Spring was observed to be impacted with viscous asphaltic material (tor); therefore, MPA Spring Mitigation System was designed and installed with KDHE approval. The objective was to capture the flow, separate and contain the viscous LNAPL, and redirect tor-free water to the MPA basin interceptor trench. As shown in Figure 1-11, the system consists of lateral trenches with perforated pipes that flow to a sump located at the spot of the former spring. Water gravity-flows to a Iorge parallel plate, coalescing underground oil water separator (UOWS). The system was installed in April 2014 and is performing as intended.

1.5.4 AHA Pit Excavation

The Asphalt Handling Area (AHA) (Figure 1-2) was formerly used to manage asphalt and o ther materials (both solids and liquids) generated during the refinery operation. The AHA included a disposal pit and approximately sixteen piles of stabilized asphalt (the AHA Piles). The AHA Pit was used to mix soil with asphalt to stabilize the asphalt. The asphalt was then removed from the pit and placed into piles. The AHA Pit is believed to be the former source of the tor in the MPA Spring. EPME-PC removed both the piles and all material within the AHA Pit down to competent rock and consolidated it w ithin the West Oxidation Pond.

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2.0 LNAPL CONCEPTUAL SITE MODEL (CSM)

This section discusses the LNAPL conceptual site model (CSM) including the distribution and controlling hydrogeology. LNAPL is present in isolated areas within the vadose soil pores at source areas; however, the majority of LNAPL migrated vertically downward 10 to 20 feet to the shallow groundwater surface and then spread laterally, resulting in the free product plumes depicted on Figure 1-5. Groundwater elevations have varied seasonally and over many years LNAPL has become trapped several feet above and below typical groundwater elevations (hereafter referred to as the smear zone). The smear zone over the majority of the Site is located within silty clayey soil; hence LNAPL migration was limited and risk of further migration is low. The following provides further detail for each area of the site:

2.1 MPA

In contrast to the rest of the Site, LNAPL in portions of MPA has historically come in contact with the more transmissive weathered bedrock surface. This is the likely historical migration pathway of LNAPL to the West Branch of the Walnut River (WBWR). No product has been observed in interceptor trenches since installation in 2006, suggesting the product is also no longer mobile. Figure 1-5 from 2009 shows the extent of LNAPL within the MPA. LNAPL recovery has been ongoing since installation of the MPA Basin interceptor trench (discussed in Section 1.5.2.1) and the extent of LNAPL has decreased as shown in Figure 1-7 from 2017.

2.2 AHA

LNAPL has not been detected in any AHA monitoring well; however, it had been measured in wells located downgradient of the former AHA pit (Figure 1-5). IRM actions have removed all asphalt-based LNAPL source to bedrock within the AHA and the residual downgradient product, located within the MPA. is being captured and recovered by the MPA Spring system.

2.3 STF

There have been historically up to seven isolated and relatively small free-phase LNAPL source areas located across the STF. Five of these areas include only one well with a measured LNAPL thickness of less than 0.1 foot. No evidence of LNAPL migration has been observed and plumes appear to be shrinking based on Figure 1-5, Figure 1-6, and Figure 1-7.

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2.4 SPA

LNAPL thickness is non-detectable under the former Stormwater Ponds and along the WBWR. The Seep IT has recovered negligible product since its installation, confirming this observation. Most product appears to be at the residua l (immobile) state with occasional fine globules freeing from the river bank (area beyond the interceptor trench) under certain conditions, such as low WBWR stage that results in maximum hydraulic gradients.

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3.0 FREE PHASE LNAPL RECOVERY

In accordance with KDHE requirements and CAS corrective action goals (CAGs), LNAPL must be addressed. This includes a component of active product recovery until LNAPL transmissivities are below reasonably recoverable limits and no further migration has been confirmed.

3.1 CONTINUED IT SYSTEM OPERATION

The Seep IT, MPA Basin IT, and MPA Trench IT (collectively, the ITs) provide hydraulic control and product recovery for the AHA MPA and SPA areas. Continued operation is proposed as detailed in the following sections:

3.1.1 Operation and Maintenance (O&M) Period

The ITs will continue to be operated until the LNAPL transmissivity in all monitoring wells upgradient of the trenches and the specific trench itself are confirmed to be below a transmissivity of 0.8 ft2/day as discussed in the September L 2015 KDHE TPH and LNAPL Charac terization, Remediation, and Management Policy (BER-041 ). However, IT operation may continue beyond this determination for other reasons, such as groundwater containment.

3.1 .2 O&M Procedures

3.1.2.1 Fluid Recovery. A Seep Interceptor Trench Draft Monitoring Plan (Draft Monitoring Plan) was submitted to the KDHE in letter format on June 2006 and the Seep IT Operational and Maintenance Manual, including record drawings, pipe materials, and equipment/pump O&M manuals was submitted in February 2007. The MPA Basin IT and MPA Channel IT record drawings and equipment manuals were included in the Interim Remedial Measures Construction Completion Report, dated May 2013. Given potential inconsistencies between documents and now well-confirmed groundwater capture, the following operation and maintenance (O&M) procedures are proposed henceforth:

• The ITs will continue to be monitored for proper operation at least monthly. This includes measurement of extracted groundwater volumes, line pressures, and confirmation of proper pump operation.

• The IT extraction sumps (ESs) , pumps, flow meters, and piping will be redeveloped and/or cleaned as necessary to maintain flow rates and hydraulic control.

• Confirmation of hydraulic control will be through site-wide gauging events at the frequency agreed to be the KDHE (currently semi-annually) .

• WBWR seep inspections will cease because hydraulic containment and the absence of surface water impacts (other than the previously noted bank drainage) have been well-confirmed over the past decade of operation.

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3.1.2.2 Groundwater Treatment System (GTS). The water treatment system O&M Manual was provided as Appendix F of the April 201 1 Final ( 1 00%) Water Treatment Design. Operation and maintenance w il l continue according to this plan. This plan includes the pre-treatment equipment: UOWS, Cascade Aerator, and Settling Basin.

The GTS UOWS has the capac ity to store 400 gallons of free product. Based on recent recovery rates, little additional product recovery is anticipated; however, fluid levels within the UOWS will be chec ked and recorded on at least a semi-annual basis. When required, LNAPL will be transferred to the onsite aboveground storage tank (AST) and will be characterized and profiled for proper d isposal.

3.2 CONTINUED MPA SPRING SYSTEM OPERATION

The MPA Spring will continue to flow indefinitely. Given 1) weathered bedrock topography directing AHA groundwater flow toward the MPA Spring area; 2) the location of the AHA Pit (the former source of the asphaltic tar) upgradient of the MPA Spring; and 3) dewatering and resulting drawdown in the MPA Spring collection sump, it is likely that most or all AHA-impacted groundwater and tar flows toward the MPA Spring area a nd hence is captured and treated by the MPA Spring gravity flow system.

3.2.1 O&M Period

The gravity-flow spring water capture and treatment system operation will continue until the KDHE concurs tar entrainment in spring water has ceased. This determination may be made by removal and cleaning of all tar from the UOWS and observing for any accumulation over a period of a t least one year.

3.2.2 O&M Procedures

Standard operation includes NPDES effluent sampling and reporting; inspection of UOWS p lates and effluent quality; cleaning and removal o f tar as frequently as required to maintain performance; and reporting of observations and activities w ith other site data in the current semi-annual (may be a nnual at some point in the future) progress report.

3.2.2.1 Product Level Checks. The tar quantities and accumulation rates in the UOWS have been moderate. The UOWS has the capacity to store several hundred gallons of product; therefore, LNAPL levels will be checked and recorded on a quarterly basis at the start of this plan. With KDHE 's approval, this may be later reduced to semi-annually or annually.

3.2.2.2 UOWS Cleaning. Large parallel, coalescing plates are used to separate the LNAPL from the groundwater, as water passes through, small amounts of LNAPL can adhere to the plates. It is likely the plates wil l become fouled before the capacity in the

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UOWS is reached therefore; the UOWS will require cleaning. The condition of the plates will be monitored and recorded when product levels are checked . When the plates are visually observed to be 60-80% covered or a buildup of residue exceeds ~~inch, the UOWS and the plates will be cleaned.

To clean the UOWS, the influent will be turned off and the recovered LNAPL will be decanted from the top of the UOWS using a vacuum truck or similar removal methods. The remaining water will then be drained to the MPA Channel. The plates and interior of the UOWS will be cleaned in place with hot pressurized water/steam or similar methods. The captured fluids within the UOWS will be vacuumed out and properly d isposed of with the accumulated LNAPL.

3.3 ADDITIONAL PRODUCT RECOVERY

LNAPL has been recently observed in 11 Site monitoring wells. These and all wells with historical LNAPL detections are listed in Table 3-1 and shown in Figure 1-5 through Figure 1-7. Apparent LNAPL thicknesses in these wells ranged from 0.00 feet up to 3.97 feet.

3.3.1 Wells in Program

All wells listed in Table 3-1 will initially be in the LNAPL program because they have recently (within the last 7 years) contained free-phase product. It is envisioned some of the wells will meet the initial round of transmissivity criteria (Section 4) and hence will continue in the confirmation transmissivity testing program described in Section 4 rather than the product recovery described in the remainder of this section (Section 3.3) .

3.3.2 O&M Frequency and Duration

Those wells failing a transmissivity test will be placed in the product recovery program. The frequency of LNAPL bailing, skimmer cleaning/product removaL and/or sorbent sock replacement O&M will depend on the recovery rates. Site visits will begin on a monthly basis and the frequency will be increased or decreased as necessary to ensure minimal LNAPL thicknesses are maintained.

Similar to the ITs, the duration of additional product recovery efforts will be based upon meeting the criteria of KDHE policy BER-041. Once a well LNAPL transmissivity is confirmed to be less than 0.8 ft2/day (see Section 4), free product recovery will cease.

3.3.3 O&M Procedures

Given the range of LNAPL thickness and that groundwater water elevations affect both the number of wells with LNAPL and the recoverability of that LNAPL the type of recovery equipment used is likely to vary among the wells and possibly between recovery events for the same wells. Monitoring well-based recovery methods are expected to be mainly

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hand boiling and sorbent socks, but passive skimmers and active skimmers will be considered if LNAPL thicknesses exceed absorbent sock capacities between site visits.

3.3.3.1 Skimmers. Passive and active skimmers include selective oil skimmers (SOS) and/or hydrophobic screens with down-well canisters to skim and store LNAPL. These will be used for the highest LNAPL transmissivity wells where hand boiling or sorbent socks require excessively frequent Site visits to complete or change-out. Cut sheets of example LNAPL skimmer equipment ore provided in Appendix A.

3.3.3.2 Hand Bailing. Hand boiling will be used for those wells with moderate thickness and transmissivity that do not warrant a skimmer system but where product recovery is too high for sorbent socks. Hand boiling consists of lowering a boiler down the well and agitating to fill with a mix of product and water. then removing and decanting the product. Recovery product w ill be stored in the GTS UOWS or AST. Recovered water will be disposed into the GTS UOWS or Precipita tion/Settling Basin (PSB) for treatment through the wetlands.

3.3.3.3 Adsorbent Socks. Adsorbent socks will be used for low transmissivity wells. Absorbent socks contain a hydrophobic media (repels water) that still sorbs LNAPL and is contained in a fabric that con be lowered down the well. As the sock sorbs product. it sinks further below water. The media does sorb some water over time; therefore. when a sock is fully utilized, it will be wrung-out over a bucket to remove all free liquids. The liquids will be placed in the GTS UOWS for treatment and the spent media will be placed in a 55-gallon drum for disposal .

3.3.4 Waste Management

All LNAPL recovered from the Site will be characterized and a waste profile will be completed for proper disposal.

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4.0 LNAPL TRANSMISSIVITY TESTING

Transmissivity testing will be completed in accordance with the procedure detailed in the American Society for Testing and Materials (ASTM) standard E2856-11 , Standard Guide for Estimation of LNAPL Transmissivity and as described below.

4.1 FREQUENCY AND NUMBER

The operating trenches and MPA Spring system are effectively providing continuous long­term LNAPL recovery-based transmissivity tests. Individual monitoring well tests will be discrete/short-term. Collection, analysis, and presentation of transmissivity data will be completed when EPME-PC believes a given location may pass the LNAPL transmissivity standard of less than 0.8 ft2/day.

4.1 .1 MPA Spring and ITs

LNAPL recovery data will be analyzed for the MPA Spring and each IT operation to date. While the volume of product recovered to date is known, exact time periods of that accumulation within the UOWS have not been historically recorded; however, reasonable estimates are possible. If it appears transmissivities are less than 0.8 ft2/day, cleaning of the IT UOWS and MPA Spring UOWS will be completed. This w ill be followed by an additional five years of monitoring to increase the accuracy of the low level LNAPL volume measurements and hence transmissivity estimate. Recovered LNAPL will be removed from each UOWS and recorded quarterly or semi-annually depending upon the recovery rate . Data will be reported in the semi-annual or annual progress reports. If results indicate a transmissivity of less than 0.8 ft2/day, LNAPL recovery wi ll be removed as a rationale for continued operation of the trenches or MPA Spring system. However, as previously noted, operation may continue for groundwater containment reasons.

4.1 .2 Monitoring Wells

All monitoring wells containing detectable levels of LNAPL within the last 7 years (highlighted in green in Table 3-1) will be gauged quarterly for product levels for a period of five years. If no measureable (<0.01 foot) product is detected during this period, the well will be removed from the list and LNAPL will be considered addressed in that area. If measurable product appears, LNAPL transmissivity tests will be attempted as described in the following paragraph. If a transmissivity measurement exceeds 0.8 ft2/day, LNAPL recovery will commence in accordance with Section 3 at that location.

Individual wells with measureable product (>0.01 foot) but a transmissivity of less than 0.8 ft2/day will undergo additional transmissivity testing. This may consist of a discrete LNAPL bail-down test (See Section 4.2.1) , skimming test (See Section 4.2.2), and possible a

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recovery-based test (Section 4.2.3). A total of four quarterly test events will be attempted, during which time no other product recovery will occur to avoid test bias. If product appears and disappears or if a test can be completed once but not the next quarter(s), the duration until all four tests are complete may be more than one year, but shall not exceed 5 years. If a well exhibits no product or too little recoverable product to test (see Section 4.1.3) , it will be assumed the result is less than the standard of 0.8 fF/day; however, gauging and future transmissivity testing may be completed if product levels sufficiently increase. If all test results indicate a transmissivity less than 0.8 fF/day and/or if too little product was present to test during the 5-year period, that well will be proposed to be removed from the LNAPL recovery program in the next progress report. Other wells will be addressed on a case-by-case basis in discussion with the KDHE.

4.1.3 Minimum Test Thicknesses/ Recoverable Product

The LNAPL bail-down/slug test requires an ASTM minimum LNAPL thickness of 0.5 feet to complete. Neither the skimming test nor recovery data-based test have limits because in certain conditions, <0. 1 foot can still be recovered through bailing or skimmers with selective oil skimmers (SOS) and/or hydrophobic screens; however, it becomes unlikely product transmissivity could exceed 0.8 ft2/day at those low thicknesses. Reasonable attempts will be made to complete a transmissivity test, including use of a skimmer. Given the time required to complete a long-term low-production test, if results indicates a transmissivity of less than 0.2 fF/day, a request may be made to the KDHE to forego future tests at that well under similar (or lesser) product thicknesses. Other conditions may also require a case-by-case evaluation and determination in consultation with the KDHE.

4.2 METHODS

ASTM standard E2856 provides for several d ifferent measurement methods depending upon site conditions such as actual product thickness and/or active product recovery in the vicinity. The four methods are described below. The most appropriate method for the location and LNAPL thickness at the time of testing will be utilized.

4.2.1 Bail-down/Slug Test (ASTM E2856 Sections 5.2 and 6.1)

An LNAPL bail-down/slug test consists of either removing all LNAPL from the well casing and filter pack or the displacement of a partial volume to induce a head differential. Following the induction of the head differentia l, fluid levels are gauged during recovery. To complete the test with reasonable data accuracy, an LNAPL thickness of at least 0.5 foot must be present. Where the bail-down method is used, LNAPL removal will not take place for at least one month prior to the testing event to ensure equilibrium fluid levels.

The initial depth to air/ LNAPL and LNAPL/water interfaces will be measured immediately prior to removal of the LNAPL. Following removal, gauging of the fluid levels will be done at an approximate frequency corresponding to a 5% change of the equilibrium-gauged

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LNAPL thickness. After the first 100 minutes of gauging, the data will be reviewed and plotted on a logarithmic scale so field staff can prepare a schedule for additional data collection. The test will be complete when LNAPL thickness stabilizes. shown by at least three measurements.

4.2.2 Manual LNAPL Skimming Test (ASTM E2856 Sections 5.3 and 6.2)

Manual LNAPL skimming test is conducted by removing LNAPL at a rate that maintains drawdown in the well until a consistent LNAPL recovery rate is achieved. This is used in conjunction with a skimming test analytical method to derive estimates of LNAPL transmissivity. LNAPL skimming tests may be completed at any well exhibiting a gauged LNAPL thickness. This test is especially useful for wells exhibiting a gauged thickness less than 0.5 feet because it allows the aboveground measurement of LNAPL volume. In addition, the error associated with estimating the recharged LNAPL volume at this initial gauged thickness can be more accurately estimated aboveground than in situ.

The test consists of repeatedly gauging fluid levels, purging the LNAPL, and gauging the well again. The recharge rate is calculated and the test continues until the well stabilizes. Prior to initiating the test, the fluid levels need to represent equilibrium and during the test. 75% of the maximum skimming drawdown must be consistently induced.

To start the test, LNAPL will be removed to the maximum extent possible and the total volume and time of removal will be recorded. Immediately after removal. the depth to air/LNAPL and LNAPL/water interfaces will be measured . When the well recovers 1

/. of the initial thickness. LNAPL will be re-purged. The test will continue until the calculated recharge into the well stabilizes. Initially, gauging measurements and re-purging may be completed at an approximate ten-minute interval and reduced to thirty minutes or an hour as field measurements dictate. After 8 hours. the data will be reviewed and a schedule for additional gauging and purging events will be prepared for subsequent measurements. When three consecutive discharge rates are within 25% of each other and there is no consistently decreasing trend, the test is complete. Note, if the well recovers within five minutes. the conditions of this test likely cannot be met; in this case, an alternate test method will be chosen for calculating transmissivity.

4.2.3 Recovery Data-Based Methods (ASTM E2856 Sections 5.4 and 6.3)

This procedure derives LNAPL transmissivities using data obtained from continuous operation of LNAPL skimmer pumps and/or other types of product recovery systems where aquifer conditions approach steady-state conditions. These recovery systems are designed to extract LNAPL groundwater, and/or formation air/vapor from a recovery well. If the recovery system is operating consistently and the LNAPL CSM is well developed and understood, this method can provide high accuracy and repeatability of transmissivity calculations. The method assumes continuous operation over the

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temporal interval of interest. Accurate system operational data are necessary to obtain representative LNAPL transmissivity values.

4.2.4 Tracer-Based Methods (ASTM E2856 Sections 5.5 and 7.0)

Tracer tests can be used in conjunction with a tracer test analytical procedure to derive estimates of LNAPL transmissivity at any properly screened well exhibiting LNAPL thickness greater than 0.2 ft in unconfined, perched, and confined aquifer materials where the fluid levels are in equilibrium with the formation. Tracer tests can be conducted under a natural or imposed gradient. An imposed gradient test can be conducted on active recovery wells and do not require fluid extraction from the test well. These tests are conducted over several weeks or months and, therefore, provide temporally-averaged and vertically-averaged transmissivity values. Imposed gradient tests can be conducted in period of hours to days. A hydrophobic fluorescent tracer and a UV /VIS spectrometer with a downhole fiber optic cable are needed to make measurements of tracer concentrations through time. This is an emerging method and is not planned for initial use at this site.

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5.0 NATURAL SOURCE ZONE DEPLETION (NSZD)

After a release into the environment, petroleum hydrocarbon constituents in LNAPL undergo various different degradation processes, including dissolution into groundwater and biodegradation in the saturated and capillary zones and volatilization, dissolution, and biodegradation in the vadose zone (Kostecki and Calabrese, 1989; NRC, 2000; Johnson et al., 2006). NSZD is a term used to describe the collective, naturally-occurring processes of dissolution, volatilization, and biodegradation in the subsurface that act to degrade LNAPL and convert petroleum hydrocarbon constituents to innocuous aqueous and gaseous by-products. These processes physically degrade the LNAPL by mass transfer of chemical components to the aqueous phase where they are biologically broken down. Within the saturated zone and overlying capillary fringe, methanogenesis is typically the most dominant biodegradation process (Weidemeier et al., 1999) , resulting in generation and subsequent transport of methane (CH4) and lesser amounts of carbon dioxide (C02) to the vadose zone. Within the vadose zone, LNAPL (if present) and volatile hydrocarbons are also anaerobically biodegraded producing additional CH4 and C02. Above this zone, where oxygen (02) permeates downward from the atmosphere, aerobic biodegradation occurs removing CH4 and 0 2 from the soil gas, adding more C02, and releasing heat to the soil. Figure 5-1 presents a conceptualization of typical subsurface vapor conditions at a petroleum release site.

Figure 5-1. Vapor Transport Related NSZD Processes at Petroleum Release Sites

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NSZD rates are reflected in the development of 0 2 and C02 concentration gradients, C02 efflux from subsurface into ambient air, and an increase in subsurface temperatures. The production of reaction by-products (C02) and intermediates (CH4) and the consumption of reactants (02) results in transport and thus flux of these constituents. Each of these is measurable and can be used to stoichiometrically estimate NSZD rates. Three NSZD monitoring methods are well-documented and currently available and have received widespread use. These include the vertical gradient. dynamic closed chamber (DCC), and passive flux trap methods. The DCC and passive flux trap methods were selected to evaluate NSZD at the Site because they are direct flux measurement techniques and have been used to successfully measure NSZD rates at various sites with pervious ground cover (Palaia, 2016) .

5.1 NSZD MEASUREMENT METHODS

NSZD estimation is a three step process including C02 efflux measurement. background correction, and stoichiometric conversion. Details of each step are described in the following sections.

5.1.1 Step 1 - C02 Efflux Measurement

Two direct methods of C02 efflux measurement will be used to estimate NSZD rates at the Site: DCC using the LI-COR® 81 OOA soil flux system and passive flux traps using the E-Fiux C02 Traps. An overview of each method follows.

5.1.1.1 Dynamic Closed Chamber Description

A DCC system is an active, specially adapted, direct measurement approach to measure soil gas efflux at the ground surface. The LI-COR® 8100A automated soil flux system (LI-COR® BioSciences, Inc.. Lincoln, Nebraska) pumps a small. closed loop circulation of air between a chamber set on a collar installed shallow (i.e., 1 to 3 inches deep) on the ground surface and an external non-destructive infrared gas analyzer (IRGA) that monitors the increase in C02 concentration. To minimize errors associated with pressure differential inside and outside of the chamber, the chamber is fitted with an engineered vent (Davidson et al., 2002) and is run for only a short time (i.e., typically 90 seconds per measurement). DCC has been demonstrated to be a consistent efflux measurement method and used as reference for comparison to others (Norman et al., 1997). The LI-COR® 81 OOA has been used primarily for ecological carbon monitoring purposes and was recently adapted for NSZD monitoring (Sihota et al.. 2011 ). Figure 5-2 shows a complete DCC C02 efflux measurement setup.

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Figure 5-2. LI-COR®8100A DCC Apparatus and Setup

The increase in C02 inside the chamber is related to the influx of soil vapor into the open bottom of the collar from subsurface sources of C02. The time rate of C02 concentration rise, or the slope of the best fit curve to the time series trend, can be equated proportionally to the C02 efflux. Figure 5-3 shows the output interface of an example LI­COR® 81 OOA data set as viewed from the LI-COR® Soil Flux Pro data management software. The lower right corner of the interface shows a plot of the C02 mole fraction corrected for water vapor dilution plotted against time. Given user-supplied parameters, the software automatically renders a best fit curve and reports the estimated C02 efflux (upper right corner). All data is post-processed using this software to ensure consistent data handling.

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Exp Flux for Cdry = 2. 260000

As Read I Current I Measurements 1 Recompute Rt#l Cdry I Revert

I c. = 364.9 a= 3. 1915e.03 C(t) = c . + (c. - C.) exp( -a(t-t:.))

C.= 454.6 to= 5. 3 Exp

I dC/dt SE ofdC/dt R' flllX Flux CV

Keep Exponential: 0.286 0.002 0.9954 2.260000 1.500000 Linear: 0.245 0.002 0.9942 1.940 1.6

Regression I De taUs 1 Guidance 1 r Manually set Co 390 -[1 -Start time j 20 ±l 385- . t!t4

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Stop time ls9 jJ 380-

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~ Exp fit 360

r Unear fit I I I I I I I I I I I I I I I I I I I I I I I I I -20 0 20 40 60 80 100

t (sees)

Figure 5-3. Example Output from a C02 Efflux Measurement Using the L/-COR® 81 OOA and Soil Flux Pro

Software

5.1.1.2 E-Fiux® Passive C02 Flux Trap Description

The passive flux trap was developed by Colorado State University and Chevron U.S.A. (U.S. Potent No. 8,714,034). It was commercialized and further refined by E-Fiux, LLC (Fort Collins, Colorado) and employs the use of a flow-through receiver pipe and sorbent to collect gases leaving the subsurface.

The trap setup is composed of three main ports: the trap body, receiver pipe, and rain cover. The traps ore installed shallow (i.e., 1 to 3 inches deep) on the ground surface and left in place for a multi-day time frame. Over this time, C02 migrating upward from the subsurface to the atmosphere is c o llected inside the flow-through receiver pipe by a caustic sorbent material. The C02 trap is placed on a receiver pipe that is installed on the ground surface. This receiver pipe provides on anchor point for the C02 trap body. The trap body is a ttached to the receiver pipe with a rubber sleeve that is impervious to gas flow. To prevent measuring atmospheric C02 that would bias soil gas efflux measurements, a two-layer system is employed . The trap is constructed with a bottom sorbent material layer to collect C02 derived from the subsurface and on upper sorbent material Ioyer to collect atmospheric C02 when gas flow reverses due to barometric changes. The trap is deployed for a period of time that does not allow for either the top

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of bottom layers to become saturated with C02 thereby preventing cross contamination of C02 between atmosphere and subsurface. A rain cover to prevent water occupying the sorption locations is needed to complete the passive flux trap assembly. Figure 5-4 shows a completed C02 Trap assembly as installed in the field.

Figure 5-4. E-F/ux Passive C02 Flux Trap Apparatus and Setup

After the deployment period, the sorbent is removed from the receiver pipe and returned to the E-Fiux laboratory for analysis. The mass of C02 collected on the lower sorbent is measured and corrected for a trip blank. The mass of C02 sorbed is divided by cross sectional area of the receiver pipe and the deployment time to estimate the C02 efflux.

5.1.2 Step 2 - Background Correction of Total C02 Efflux Measurements

Estimating NSZD rates using C02 efflux is complicated by natural soil respiration (Rochette and Hutchinson, 1999). There may be background C02 production unrelated to the presence of the hydrocarbon source. This includes contributions from plant roots and microbes present in surficial and deeper soils containing natural organic matter. These processes tend to be most significant in the root zone and diminish with increasing depth; therefore, background correction must be made before estimating NSZD rates using C02 efflux data.

There are numerous challenges with background correction using results from outside the LNAPL footprint, especially at sites with diverse ground cover and/or very active natural soil processes. More complex site conditions will drive selection of a more complex background correction process. Options that will be considered to account for the contribution of natural soil respiration to C02 fluxes at the Site include:

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• Background C02 efflux monitoring outside the LNAPL footprint, or • Measuring 14C radiocarbon to identify the contribution of C02 originating from

petroleum vs. non-petroleum sources (Sihota and Mayer, 2012).

The simple approach to eliminate flux contributions from non-NSZD processes is to install flux measurement locations in a nearby uncontaminated setting with similar surface and subsurface conditions. The number of background locations will be driven by the variability in the background efflux results. If large variability is observed, then more background monitoring will be required. Calculation of C02 efflux from petroleum hydrocarbon sources (NSZD) using this approach is estimated by subtracting the C02 efflux measured at the background location from the total uncorrected C02 efflux from each survey location.

The second, more direct approach is to use 14C radiocarbon analysis on carbon in C02 collected by the E-Fiux traps. The use of 14C provides an alternative, more accurate means to isolate the NSZD-derived C02 efflux without the need to monitor outside areas. The 14C analysis provides which fraction of the C02 efflux is derived from modern or older sources. This accelerator mass spectrometer analysis investigates the ratio of 14C to 12C. 14C degrades over time to 12C, thus a lower ratio 14C:12C in the C02 indicates the carbon is derived from older sources, such as petroleum derivatives. Radio isotope analysis of 14C is a determination of the fraction of modern carbon contained within the sample. Modern carbon is associated with plants/vegetation and other natural organic matter in the ecosystem. It is distinctly different from carbon derived from LNAPL biodegradation as it is significantly younger in comparison to carbon derived from biodegradation of fossil fuel petroleum hydrocarbon. By assuming zero modern carbon in the fossil fuel fraction and a known modern 14C carbon fraction in the atmosphere, the fossil fuel fraction of the total C02 efflux can be measured. This approach will be used where the background monitoring approach is deemed insufficient and where typical project constraints (i.e., budget and schedule) allow.

5.1.3 Step 3 - Stoichiometric Conversion of C02 Efflux to an NSZD Rate

The corrected C02 efflux results can then be used to estimate an NSZD rate. An NSZD rate expressed as total hydrocarbon degraded (g/m2fd) is calculated at each survey location by multiplying the background corrected soil C02 efflux ( mol/m2/s) by the molar ratio of hydrocarbon degraded to C02 produced in a representative mineralization reaction. As an example, the mineralization of octane is represented by:

In this example, to estimate the mass of octane degraded, the C02 efflux would be multiplied by the molar ra tio of octane to C02 (i.e., 2/16). In this example, a mass-based

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NSZD rate can be calculated by multiplying again by the molar weight of octane ( 114 g/mol). To obtain a volume-based NSZD rate, a site-specific LNAPL density is used to convert the mass-based NSZD results (i.e., g/m2/d) to volume-based results (i.e., gal/ac/yr) that tend to be more comprehensible in a site remediation technology effectiveness context.

5.2 NSZD ASSESMENT WORK PLAN

The objectives of the NSZD evaluation at this site are:

1. Confirm the presence of NSZD in these areas of the site, including petroleum NAPL and NAPL-impacted wastes/soil within the:

a. Main Process Area (MPA) b. South Tank Farm (STF) , including the northern portion of the residential area

Areas within the Asphalt Handling Area (AHA) may be surveyed, but only as needed to monitor background locations for C02 efflux correction.

2. Quantify the range of NSZD rates (gal/ac/yr and gal/yr) that are occurring in these areas during the peak (warm) and low (cold) seasonal times of year.

3. Determine the ability/effectiveness of NSZD to treat residual hydrocarbons. If confirmed, NSZD will help achieve the Corrective Action Goals (CAGs) of 1) controlling migration of contaminants from soils that hinder achieving groundwater ARARs, thereby 2) preventing further degradation of the aquifer, and 3) restoring groundwater to its most beneficial use. Indirectly, NSZD will a lso help address the CAGs of 4) preventing off-site migration of the dissolved-phase plumes or LNAPL 5) protecting the WBWR and intermittent STF Creek, and 6) preventing exposure to all soil, soil vapor, and groundwater exceeding RBSLs. NSZD effectiveness will be demonstrated by the following:

a. Measured mass loss rates via NSZD that are greater than estimated in situ LNAPL mass flux as evidence of its ability to control LNAPL migration

b. Measured mass loss rates via NSZD larger than historically achieved by other active remediation means and thereby meets the needs of remediation of LNAPL to the extent practical

c. Projected duration of NSZD to achieve CAGs is reasonable as compared to active remediation systems.

An initial comprehensive assessment of NSZD will be conducted using both the DCC and Trap methods. The initial assessment will verify the occurrence and quantify the magnitude of NSZD that is occurring across the site over seasonal warm and cold times

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of the year. After initial verification, the sustainability and effectiveness of NSZD will be monitored every five to ten years. The long-term monitoring will verify the NSZD rates relative to those measured during the initial assessment at selected key locations over the residual LNAPL. The results of this NSZD assessment will be coupled with the groundwater-based Monitored Natural Attenuatio n (MNA) results to estimate a tota l petroleum hydrocarbon degradation rate a t the Site and more comprehensive ly track the progress of overall Site restoration. Further details regard ing the initial and long-term NSZD monitoring events are provided in the following sections.

5.2.1 Initial Verification and Quantification of NSZD

The initial verification and quantification of NSZD at the Site will be assessed through a network of approximately 120 C02 efflux survey locations as shown on Figure 5-5. The survey network is focused on residual LNAPL areas within the MPA and STF and also includes surrounding areas for background monitoring. The initial survey network is designed to be reasonably comprehensive in order to provide a detailed snapshot of C02 efflux at the multitude of varied release areas across the Site. As discussed below, the C02 efflux monitoring will be performed using a real-time, dynamic, data collection and analysis routine and therefore the actual survey network may vary slightly from the work plan. Additional details on the approach and methodology are provided in the following subsections.

5.2.1.1 Approach and Methodology

Dynamic Closed Chamber

The LI-COR® 81 OOA automated soil flux system will be used to survey C02 efflux at all prescribed locations across the Site. The 20-centimeter diameter, single-chamber survey system with integrated pump, infrared gas analyzer (IRGA), and control unit will be used . The survey c hamber will be set on polyvinyl c hloride (PVC) collars set shallow ( 1 to 3 inches deep) on the ground surface a t each location. The C02 efflux survey will be performed in the following general sequence: vegetation removal and collar installation followed by 12 to 24 hours of soil vapor re-equilibration, C02 efflux measurements, data review and quality assurance measurements, collar removal, and demobilization. The results of the measurements will be periodically reviewed to determine if additional locations or modifications in the procedures are necessary. The program will be adapted as needed to collect data to meet the data objectives (see Section 5.2) . Additional details and field procedures for the DCC method are provided in Appendix B.

Passive Flux Trap

E-Fiux C02 traps will be installed at approximately 12 of the C02 efflux survey locations across the Site . The purpose of the traps are to supplement the LI-COR® data and

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facilitate more accurate background correction. C02 traps will be installed in varied release areas atop the known residual LNAPL footprint and in various types of ground cover (e.g., light and heavy vegetation) and subsurface lithology (e.g., shallow and deep bedrock) . The locations of the E-Fiux C02 traps will be based on the results of the LI-COR® efflux measurements, and the number of traps may be adjusted as needed to achieve the data objectives. The E-Fiux traps will be installed according to manufacturer's recommendations. 14C radiocarbon analysis will be performed on all traps to estimate the fossil fuel fraction of the C02 efflux and determine NSZD rates. Additional details and standard operating procedures (SOPs) for trap receiver pipe installation and manufacturer's currently recommended trap deployment procedures are provided in Appendix C.

5.2.1.2 Procedures

Dynamic Closed Chamber

Each LI-COR® location (as shown in Figure 5-5) will be clearly marked for current and future locating with surveyor markings (e.g., stake, flagging, and whiskers). Those within regular pedestrian and vehicular traffic areas will be marked with stakes and caution tape for the duration of the effort to avoid disturbance. Reasonable efforts will be made to put efflux measurement locations away from heavy use and vehicular traffic type areas. At each survey location, an 8-inch diameter, 5-inch long PVC collar wil l be installed using hand tools (hand trowel and rubber mallet). The surficial root zone (anticipated to be 6-12" thick) will be removed using a small spade and the PVC collar will be installed inside the excavated area beneath the root zone. Standardized ground surface preparation procedures are provided in Appendix B.

Two rounds of C02 efflux measurements with the LI-COR® 81 OOA SOP (provided in Appendix B) will be completed. One measurement will be conducted prior to installing the C02 traps; the second measurement will be conducted upon retrieval of the C02 traps approximately two weeks later. Vapor grab samples will also be collected from the return air stream from the LI-COR® flux system for field measurement of 0 2, CH4, and C02, using a landfill gas meter (e.g., Landtec GEM2000 or equal) and CH4 and volatile organic compounds (VOCs) using a flame ionization detector (FID) equipped with and without a carbon/charcoal filter. The results will be used to validate the basis for the NSZD calculations, namely that the majority or all of CH4 and VOC vapors emitted at the ground surface are oxidized to C02. The raw C02 efflux data will be corrected for background efflux using the procedures outlined in Section 5.2.1 .5 Additional LI-COR® system details and field procedures are provided in Appendix B.

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Passive Flux Trap

Using the results from the first round of LI-COR® C02 efflux measurements, E-Fiux C02 traps will be installed and deployed following the SOP (current version provided by E-Fiux in Appendix C , subject to change). The receiver pipes for the traps will be installed using the manufacturers recommendations provided in Appendix C. After an approximately two week deployment, the sorbent traps will be retrieved and returned to the E-Fiux laboratory for specialty analysis. This analysis includes total carbon and radiocarbon ( 14C) . A second round of LI-COR® soil gas C02 efflux measurements will be collected concurrently with trap retrieval. Additional details regarding standard operating procedures (SOPs) for E-Fiux trap receiver pipe installation and trap deployment are provided in Appendix C.

5.2.1.3 Seasonality Assessment

To assess potential seasonal effects on C02 efflux at the Site, two initial NSZD verification/quantification measurement events will be completed: one during the warmest subsurface temperatures (early fall) and the other during the lowest (early spring). Fluctuating subsurface temperatures, wet and dry precipitation periods, and water tables can result in significant changes in NSZD rates. Decreasing temperatures within the subsurface residual LNAPL due to downward propagation of ambient cooling can reduce biodegradation rates. Increased precipitation alters soil moisture profiles and thereby limits soil vapor diffusion and can reduce NSZD rates. Water table fluctuations effectively expose and submerge LNAPL zones in a cyclical manner and can also affect C02 efflux and NSZD rates. The results from the two seasonal events will be used to estimate the site-wide annual NSZD rate (gal/yr).

5.2.1.4 Quality Assurance and Quality Control

In addition to the manufacturer's recommended QA/QC (e.g., LI-COR® instrument calibration) , the following procedures will also be implemented:

• Field blank- relevant to the DCC method, the chamber is placed on an air-tight collar and allowed to collect a series of blank measurements. One field blank will be analyzed per field day during the assessment. The field blank results are used to determine the instrument detection limit .

• Trip blank- relevant to the passive flux trap method, a laboratory-sealed trip blank trap accompanies the shipment from point of origin through field deployment and back to laboratory. Results are used to measure the incidental amount of C02 sorbed during transport and deployment. This is subtracted from all other traps to

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correct for atmospheric cross-contamination due to imperfect seal on traps during shipment.

• Duplicate - relevant to both methods, used to assess repeatability of measurements either side by side or immediately sequential in time. Duplicates will be collected at a frequency of one per every ten parent samples for a total of approximately 12 duplicate LI-COR® locations and two duplicate C02 traps.

The results of the QA/QC samples will be used to perform a data quality evaluation, similar to that performed on groundwater analytical chemistry results. For example, detection limits will be assigned, results adjusted for cross contamination during transport. and data will be qualified due to poor duplicate correlation in the field using a relative percentage difference value.

5.2.1.5 Data Analysis and Reporting

The following data analysis tasks will be conducted following completion of each C02 efflux field survey event, and upon receipt of the laboratory analytical data (typically within 4 to 6 weeks of sample receipt) :

• Perform QA/QC on the analytical data received from the laboratory and field.

• Correct the LI-COR® data for background C02 efflux following the procedures specified in Section 5.1.2.

• Calculate the NSZD rate for each LI-COR® and C02 trap monitoring location.

• Plot the NSZD rates for the two seasonal monitoring events (early fall and early spring) and estimate a site-wide NSZD rate.

• Prepare an NSZD assessment report to summarize the results of the C02 efflux survey and evaluate the effectiveness of NSZD as a remedial strategy for the Site. The report will include graphics, a tabulated summary of the data analysis, appendices with the C02 trap laboratory reports, and raw data from the LI-COR® efflux survey.

5.2.2 Long-term NSZD Monitoring

After the two initial comprehensive NSZD monitoring events, long-term NSZD monitoring will be implemented every five years for a duration of 15 years. Afterwards, the long-term monitoring interval may be adjusted to ten years if the data suggests sustainable and effective rates of LNAPL degradation continue to occur. Long-term NSZD monitoring will be used to verify remedial progress at the Site and quantify changes in NSZD rates at selected locations across the Site.

Page 5-11

5.2.2.1 Approach and Methodology

C02 traps at approximately 12 locations will be used as the primary method of long­term NSZD monitoring at the Site. These locations wi ll be proposed in the first year NSZD report. No monitoring using the DCC method is proposed because long-term monitoring does not require the some data density as the initial assessment. The C02 traps will be used to spot check NSZD rates at individual locations and will be compared to rates from the initial event(s) to track the progress of source depletion. The locations of the long-term monitoring will be determined based on the results of the initial NSZD verification/quantification assessment.

5.2.2 .2 Procedures

Similar to the initial NSZD assessment, C02 traps will be installed and deployed following the E-Fiux SOPs (provided in Appendix C). The long-term monitoring locations will be as close as possible to the original survey locations used during the initia l NSZD assessment. After a deployment period of approximately two weeks, the C02 traps will be retrieved according to the SOPs. The traps will be sent bock to E-Fiux for laboratory analysis of sorbed C02 and 14C and data reporting.

5.2.2.3 Quality Assurance and Quality Control

One trip blank and two duplicate traps will be deployed during each long-term NSZD monitoring event. Trip blank and duplicate sample descriptions ore described in Section 5.2.1.4. The results of the QA/QC samples w il l be used to perform a data quality evaluation, similar to that performed on groundwater analytical chemistry results. For example, results will be adjusted for cross contamination during transport and data will be qualified due to poor duplicate correlation in the field using a relative percentage difference value.

5.2.2.4 Data Analysis and Reporting

The following data analysis tasks will be conducted following completion of the efflux survey event, and upon receipt of the laboratory analytical data:

• Perform QA/QC on the analytical data received from the laboratory.

• Tabulate and chart the change in NSZD rote for each C02 trap monitoring location. Long-term monitoring will include radiocarbon (14C) doting as the background correction approach. NSZD rates will be compared to earlier rates calculated during the initial assessment to trac k and monitor source zone depletion over time.

• An NSZD Evaluation report will be prepared to present the results of the C02 efflux survey and evaluate the effectiveness of NSZD as a long-term remedy for the Site. The report will include graphics. a tabulated summary of the data analysis, and appendices with the C02 trap laboratory reports.

Page 5-12

6.0 REFERENCES

Davidson, E.A., Savage, K., Verchot, L.V., Navarro, R., 2002. "Minimizing artifacts and biases in chamber-based measurements of soil respiration." Agric . For. Meteorol. 113, 21-37.

Interstate Technology & Regulatory Council (ITRC). 2009. Evaluating Natural Source Zone Depletion at Sites with LNAPL. LNAPL-1. April.

Johnson, P., P. Lundegard, and Z. Liu . 2006. "Source Zone Natural Attenuation at Petroleum Hydrocarbon Spill Sites-1: Site-Specific Assessment Approach." Groundwater Monitoring & Remediation. 26, issue 4: 82-92.

Kostecki, P.T. and E.J. Calabrese. 1989. Petroleum Contaminated Soils, Volumes 1 through 3. Lewis Publishers, Inc., Chelsea, MI.

KDHE, 2016. Final Corrective Action Decision, Former Coastal Refinery, ElDorado Site (Case No. 03-E-0021), ElDorado, Kansas, November 2016.

Lundegard, P.D. and P.C. Johnson. 2006. Source Zone Natural Attenuation at Petroleum Hydrocarbon Spill Sites-11: Application to a Former Oil Field. Ground Water Monitoring & Remediation. Vol. 26, No.4, pages 93-106.

McCoy, K., J. Zimbron, T. Sale, and M. Lyverse. 2015. Measurement of Natural Losses of LNAPL Using C02 Traps. Ground Water. Vol . 53, No. 4, pp 658-667.

MWH, 2006. Seep Interceptor Final Design, El Paso Merchant Energy-Petroleum Company, ElDorado Refinery, ElDorado, Kansas, February 2006.

MWH, 2007. Seep Interceptor Trench Record Drawings, El Paso Merchant Energy­Petroleum Company, ElDorado Refinery, ElDorado, Kansas, February 2007.

MWH, 2009a. Third Phase Environmental Investigation Report, El Paso Merchant Energy­Petroleum Company, ElDorado Refinery, ElDorado, Kansas, September 2009.

MWH, 2010c. MPA Grading, Sewer, and Basin Design Report, El Paso Merchant Energy­Petroleum Company, ElDorado Refinery, ElDorado, Kansas, April 2010.

MWH, 201 Ob. Asphalt Handling Area Stabilization Treatability Study Letter Report, El Paso Merchant Energy-Petroleum Company, El Dorado Refinery, El Dorado, Kansas, September 201 0.

MWH, 2011 d. Addition of an Underground Oil/Water Separator (UOWS) to the April 2011 , Final ( 1 00%) Water Treatment Design, El Dorado Refinery, El Dorado, Kansas, letter and Technical Memo design July 2011.

MWH, 2011c. Final (100%) Water Treatment Design, El Paso Merchant Energy-Petroleum Company, El Dorado Refinery, ElDorado, Kansas, April 2011 .

Page 6-1

MWH. 2011 b . Final (1 00%) Wastewater/Stormwater Pond and Asphalt Handling Area Interim Measures Closure Work Plan/Design. El Paso Merchant Energy­Petroleum Company, ElDorado Refinery, ElDorado, Kansas. May 2011.

MWH. 2012b. MPA Spring Mitigation System Design, El Paso Merchant Energy-Petroleum Company. ElDorado Refinery. ElDorado, Kansas. June 2012.

MWH. 2013. Interim Remedial Measures Construction Completion Report. El Paso Merchant Energy-Petroleum Company, El Dorado Refinery, El Dorado. Kansas. May 2013.

MWH. 2014. Final Corrective Action Study, El Paso Merchant Energy-Petroleum Company, Former Coastal Refinery, ElDorado, Kansas, July 2014.

National Research Council (NRC). 1993. In Situ Bioremediation - When Does It Work? Committee on In Situ Bioremediation. Water Science and Technology Board. Commission on Engineering and Technical Systems. National Academy Press. Washington D.C.

Norman, J.M., C.J. Kucharik. S.T. Gower. D.D. Baldocchi. P.M. Crill. M. Rayment, K. Savage, and R.G. Striegl. 1997. "A comparison of six methods for measuring soil-surface carbon dioxide fluxes." Journal of Geophysical Research , Vol. 102. No. D24, pp 28.771-28.777, December 26.

NRC. 2000. Natural Attenuation for Groundwater Remediation. Committee on Intrinsic Remediation. Water Science and Technology Board. Board on Radioactive Waste Management. Commission on Geosciences, Environment. and Resources, National Academy Press. Washington D.C.

Palaia. T. 2016. Natural Source Zone Depletion Rate Assessment. Applied NAPL Science Review. Volume 6, Issue 1, May.

Rochette. P. and G.L. Hutchinson. 2005. Measurement of Soil Respiration in situ: Chamber Techniques. Publications from USDA-ARS I UNL Faculty. Paper 1379. http://digitalcommons.unl.edu/usdaarsfacpub/ 1379.

Sihota. N. J .. 0. Singurindy. and K.U. Mayer. 2011. "C02-Efflux Measurements for Evaluation Source Zone Natural Attenuation Rates in a Petroleum Hydrocarbon Aquifer". Environment, Science and Technology. 45: 482-488.

Sihota. N. J .. and K.U. Mayer. 2012. "Characterizing Vadose Zone Hydrocarbon Biodegradation Using Carbon Dioxide Effluxes. Isotopes and Reactive Transport Modeling." Vadose Zone Journal. 11. no. 4.

Wiedemeier. T.H .. H.S. Rifai. C.J. Newell. and J.T. Wilson. 1999. Natural Attenuation of Fuels and Chlorinated Solvents in the Subsurface. New York: John Wiley & Sons.

Page 6-2

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TABLE 3-1

HISTORIC PRODUCT/ LNAPL THICKNESSES EL PASO MERCHANT ENERGY-PETROLEUM COMPANY

FORMER COASTAL REFINERY, ELDORADO, KANSAS

Well Range 2017 Maximum

(ft) (ft) OW-24 0.14-3.97 3.97 MW-02 0.68-3.74 3.23

MW-103D 0.72- 1.82 1.67 MW-66 0.02- 0.78 0.78 MW-41 0.00- 0.45 0.45 MW-28 0.00- 1.45 0.44 MW-09 0.00-0.30 0.30 MW-58 0.00- 0.72 0.24

MW-110 0.01-0.19 0.18 MW-122 0.00-0.18 0.06

N6-1 0.00-0.11 0.03 MW-31S 0.00-0.02 0.00 MW-45 0.00- 1.17 0.00 OW-12 0.00-0.02 0.00 OW-13 0.00-0.35 0.00

MW-SB-14 0.00-2.39 0.00 MW-33 0.00-0.04 0.00 MW-37 0.00- 0.73 0.00 MW-62 0.00-0.15 0.00 MW-82 0.00-0.02 0.00

W-24 0.00-0.02 0.00

Notes:

Wells listed in order of highest to lowest current LNAPL Thickn

Shaded = Currently contains light non-aqueous phase liquid

Range shown is from November 2010 to November 2017.

-u.

nLE NAI.A[ EJ Dorado Site Map dwg

APPENDIX A LNAPL SKIMMER CUT SHEETS

Stantec

8()().624-2026 www.qedenv.com

QED Environmental Systems

Free Product Recovery Equipment Catalog The Broadest Range of Equipment for Effective Removal of Floating Hydrocarbons and DNAPL

Equipment Selection Guidelines Selecting the best equipment for LNAPL and DNAPL source reduction depends on matching it to the site conditions and project goals. The major factors to consider are:

What are the project goals and constraints? The starting point for equipment selection is the consideration of factors such as: the importance of pumping LNAPL or DNAPL only, and not water; the expected duration of the project and total volume of LNAPL or DNAPL to be removed; the availability of site labor for

service; and the overall budget.

Does everything fit into the well? Equipment selection depends on well diameter, well depth, depth to water and its fluctuation, and LNAPL or DNAPL layer thickness.

What's being removed? The type of fuel or solvent, its viscosity, density, temperature, age of spill, and the presence of biological growth or debris affect equipment performance.

What LNAPL or DNAPL removal rate is needed? The hydraulic conductivity of the formation, the LNAPL or DNAPL recovery rate in the wells, and the pumping strategy determine the maximum LNAPL or DNAPL flow rate that will be required.

You can get prompt, expert assistance on equipment selection by calling QED to speak to an experienced applications specialist at

800-624-2026.

......

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Free Product Recovery Equipment Application Overview

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Fresh gasoline

Weathered diesel or fouled fuel conditions

LNAPL target layer thickness <2 in.

LNAPL target layer thickness >2 in.

Water table fluctuation <12 in.

Water table fluctuation > 12 in.

Below·grade vault well termination needed

Water exclusion extremely important

System off-time control important

Water column below floating layer <18 in.

No contact of drive air with pumped liquid

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Overview Genie® skimmers are safe, reliable and complete systems for remov­ing floating LNAPL layers from wells. The SPG and SQS® AutoGenie TM

and Programmable Genie® skimmers are air-operated selective LNAPL removal systems with a high suction pump and a floating inlet designed to follow the LNAPL layer as the ground water level fluctuates. The SPG version uses a specific gravity float and the SOS version uses a hydrophobic screen to avoid taking in water. All Genie skimmer systems pump the LNAPL using a special bladder pump with high suction capability, positioned above the floating inlet section of the system. The use of a bladder pump eliminates air contact with the LNAPL fluids, minimizing emulsification and eliminating VOC emissions. The AutoGenie uses an integral pneumatic timer to control the pump fill and discharge times. The Programmable Genie uses an electronic controller mounted outside the well to allow adjustment of pump cycles and off times. A complete line of matched accessories is available to help with installation and performance, including in-well tubing and hose, well caps, LNAPL collection tank full shutoffs and other items.

Advantages

1 Specialized bladder pump is extremely durable, provides high suction to maintain flow and eliminates contact of drive air with pumped fluid.

2. Choice of two types of selective floating inlets. 3. Choice of Continuous Automatic or Programmable cycling. 4. Available in several different lengths and diameters to accommodate

specific well conditions. 5. Low air consumption.

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Model Overview Chart

Maximum LNAPL Float Travel Overall Maximum LNAPL Surface Control Recovery Rate • Ranges Lengths Viscosity Required AutoGenie SPG2 - 2 in. wells 160 gpd 15 in., 24 in., 45 in., 95 in. to 130 in. 1000 centistokes No 1605 Lpdl 138 em, 61 em, 114 em) 1241 em to 330 em)

320 gpd 15 in., 24 in., 45 in., 118 in. to 153m. 1000 cent1stokes No 0,211 Lpdl 138 em, 61 em, I 14 em) 1300 em to 389 em) AutoGenie SPG4 - 4 in. wells 160 gpd 24 in., 45 in., 60 in., 109 in. to 145 in. 1 000 centistokes No (605 Lpdl (61 em, 114 em, 152 em) (277 em to 368 em)

320 gpd 24 in., 45 in., 60 in., 133 in. to 169 in. 1 000 centistokes No 11,211 Lpdl 161 em, 114 em, 152 eml 1338 em to 429 em) AutoGenie 5054 - 4 in. wells 160 gpd 12 in., 24 in., 48 in., 90 in. to 129 in. 200 centistokes No (605 Lpdl 130 em, 61 em, 122 em) 1229 em to 328 em)

320 gpd 12 in., 24 in., 48 in., 115 in. to 153 in. 200 centistokes No 11,211 Lpd) 130 em, 61 em, 122 em) 1292 em to 389 em) Programmable Genie SPG2 - 2 in. wells 160 gpd 15 in., 24 in., 45 in., 84 in. to 119 in. 1000 centistokes Yes 1605 Lpdl 138 em, 61 em, 114 em) (213em to 302 em)

320 gpd 15 in., 24 in., 45 in., 108 in. to 144 in. 1000 centistokes Yes 11,211 Lpdl 138 em, 61 em, 114 em) (274 em to 366 em)

Programmable Genie SPG4 - 4 in. wells 160 gpd 24 in., 45 in., 60 in., 99 in. to 136 in. 1000 centistokes Yes (605 Lpd) 161 em, 114 em, 152 em) 1251 em to 345 em) 320 gpd 24 in., 45 in., 60 in., 123 in. to 160 in. 1000 centistokes Yes 11,211 Lpdl (61 em, 114 em, 152 em) 1312 em to 406 em) Programmable Genie 5054 - 4 in. wells 160 gpd 12 in., 24 in., 48 in., 80 in. to 119 in. 200 centistokes Yes 1605 Lpd) (30em, 61 em,l22 em) (203 em to 302 em)

320 gpd 12 in., 24 in., 48 in., 105 in. to 143 in. 200 centistokes Yes 11,211 Lpd) 130 em, 61 em, 122 em) 1267 em to 363 em)

• gpd = gallons per day, Lpd = lrters per day

•--• Characterize Your Specific Site The QED Test Kit enables you to measure the density and viscosity of your actual floating hydrocarbon layer. This FREE, do-it-yourself kit comes complete with simple, illustrated instructions. Once you have

recorded the results of your hydrocarbon test, QED application specialists will be able to provide expert technical assistance in system design and specification.

5

P.O. Box 3726 Ann Arbor, Ml48106 USA 800-624-2026 F 734-995-1170 info@qedenv.com www.qedenv.com

REFILL

6

Floating Intake

DISCHARGE How It Works

All Genie® Systems The free product enters the skimmer system through the floating inlet, flows down through a flexible tube, then is pulled upward by the pump's suction action during the fill cycle.

During the discharge cycle, the bladder is squeezed by the compressed air and the LNAPL is pumped to the collection system at the ground surface. Then, during the fill cycle the compressed air around the bladder is exhausted again and the specialized, high- rebound bladder expands, resuming its original shape. This pulls fluid into the bladder through the check valve at the bottom of the pump.

ClOOM Pump Controller The ClOOM Digital Controller offers easy and flexible control of skimmer system opera­tion in a compact, solar and AC-powered unit. Touch-pad control and digital display simplify its programming. Programmable Genies® utilize the ClOOM Controller which allows the user to not only control the pump fill/discharge cycles, but also to set OFF periods to match the LNAPL pumping rates to the recovery rates of the well. The ClOOM includes an AC power supply for locations where solar power is either not available or insufficient to support high rate pump operation. In solar-powered mode, the Cl OOM is rated intrinsically safe. See page 40 or consult the factory for more detailed information on the C 1OOM.

T QED --

SPG Inlet The SPG (specific gravity) inlet uses a float with a controlled specific gravity that causes it to float on water but not in the free product. The SPG float has its fluid top inlet port positioned near the top so that it is always above water. If the LNAPL layer gets too thin, the SPG inlet will also be above the LNAPL layer and cease recovery of hydrocarbons until more enters the well. To accommodate a range of final LNAPL layer thickness, the SPG float has multiple, variable inlet ports that can be opened or plugged in the field to adjust the effective level of the inlet port.

Note: The SPG inlet is designed to recover thin, as well as thicker, more viscous hydrocarbons.

SOS® Inlet The SOS (selective oil skimmer) inlet uses a float with an inlet port inside a hydrophobic screen. The hydrophobic screen avoids taking in water, even if the float occasionally sticks or drags as the liquid level fluctuates. While this is a distinct advantage of the SOS inlet over the SPG type, the SOS inlet screen is more subject to plugging due to potential debris or "biogrowth" present in the well. The SOS inlet is best used for less viscous hydrocarbons, as shown in the specification charts.

Note: The SOS inlet is designed to recover thin, less viscous hydrocarbons.

SPG Float

SOS Float

Stainless Steel Outer Screen

++-Coil

Top Inlet Port

Variable Side Inlet Ports

--Coil

P.O. Box 3726 Ann Arbor, Ml48106 USA 800-624-2026 F 734-995-1170 info@qedenv.com www.qedenv.com

7

ClOOM Controller

ClOOM Controller

I Fixed Inlet I I Float1ng Inlet I L Ferrets :....J L Ferrets :.J

Overview Ferret® In-Well Separators provide an alternative method for reliably and safely removing free product from water at remediation wells, sumps and tanks. Instead of relying solely on a selective inlet float to avoid water intake, the Ferret uses a unique internal separator valve to sense the difference in specific gravity between the hydrocarbon and water, then pumps pure hydrocarbon and rejects any water back into the well. This in-well separation method can be advantageous for well conditions that hinder the performance of hydrophobic screens. Fixed Inlet Ferrets have the best resistance to fouling in difficult wells. All Ferrets use the extremely rugged and simple air displacement pumping principle to pump the LNAPL to the surface, and the programmable, solar-powered ClOOM Controller to select pumping cycle times and system OFF periods to match LNAPL recovery rates. Ferret models are available in sizes to fit 2" and 4" wells. Models are offered with or without floating inlets to match site needs and user preferences; floating inlets can improve overall LNAPL pumping rates, but the restrictions inherent in floats and tubing coils can hinder LNAPL flow in wells that are highly fouled or have high viscosity fluids. A complete line of matched accessories is available to help installation and system performance, including in-well tubing, well caps, LNAPL collection tank full shutoffs and other items.

Warranty Ferrets are warranted for one (1) year.

Advantages

1. Unique design uses specific gravity differences to separate LNAPL from water down well.

2. For sites with well conditions that hinder proper functioning of hydrophobic screens. 3. Available in sizes to fit 2" and 4" wells. 4. Simple, rugged, air-powered pump is durable and easy to maintain. 5. Programmable, solar-powered controller provides easy flexibility of pumping rates

and OFF times to optimize LNAPL recovery rates.

T QED --20 -------------------------------------------------------------------------

How the Ferret Works

Refill Cycle: Air Supply OFF Hydrocarbon (red) and/ or water (blue) enter the inlet. As the pump fills, water settles to the bottom and hydrocarbon droplets coalesce and float on top. The lower check ball floats and rises, preventing water from entering the bottom of the pump.

Water Discharge Cycle: Air Supply ON Air pressure forces the lower check ball down, while the upper check ball floats, allowing water to exit the bottom of the pump. Low pressure in the pump keeps the pressure check valve shut, blocking the dis­charge line so no water is pumped to the surface.

ClOOM Pump Controller

Hydrocarbon Discharge Cycle: Air Supply ON After the water is gone, the upper check ball sinks in the hydrocarbon and seats, closing off the pump bottom and allowing pump pressure to build. The pressure check valve opens, releasing hydrocarbon into the pump discharge line and tube to the surface.

The ClOOM Digital Controller is solar-powered and provides advanced operational capabilities at an economical price. Easy-to-use digital control of pump discharge and refill cycles and programmed OFF times make it convenient to optimize LNAPL recovery to match site conditions.

Tank full shutoff for the collection tank is a safe, simple and inexpensive add-on to the ClOOM, as an optional level control function. The ClOOM includes both a highly effective solar power system and a conventional AC power supply. Under solar-powered operation, the Cl OOM is CSA rated as intrinsically safe.

P.O. Box 3726 Ann Arbor, Ml48106 USA 800-624-2026 F 734-995-1170 info@qedenv.com www.qedenv.com

ClOOM Controller

High Capacity (4" well) and Standard (2" well) Product-Only Pumps Floating Inlet Ferret® models provides a unique combination of capabilities that result in high LNAPL removal rates from remediation wells, sumps and tanks - with no water pumping in the recovered product. The float assembly tracks changing liquid levels, keeping the inlet precisely positioned in the floating layer for maximum LNAPL recovery with each ON/ OFF cycle. The patented Ferret internal separator valve senses the specific gravity difference between hydrocarbon and water, pumping pure hydrocarbon to the surface and rejecting water back into the well. This capability is ideal for projects where contaminated ground water treatment and disposal costs are a concern. Versatile Ferret pumps recover hydrocarbons with the widest specific gravity range (0. 76-0.90) of any available device, making them an effective solution at most LNAPL sites. All Ferret models use the simple, extremely rugged air displacement pumping principle, with high internal clearances to reduce clogging and minimize maintenance. The programmable, solar-powered Cl OOM Controller makes it easy to select pumping cycle times and system OFF periods to fine-tune recovery rates to the well's recharge capacity. A complete line of matched accessories is available to simplify installation and maximize system performance; included are engineered well caps, in-well hose or tubing, LNAPL collection tank full shutoffs and other items.

Warranty Ferrets are warranted for one (1) year.

Advantages

1. Unique design uses specific gravity differences to separate LNAPL from water down well.

2. For sites with well conditions that hinder proper functioning of hydrophobic screens. 3. Available in sizes to fit 2" and 4" wells. 4. Simple, rugged, air-powered pump is durable and easy to maintain. 5. Programmable, solar-powered controller provides easy flexibility of pumping rates and OFF

times to optimize LNAPL recovery rates. 6. Floating inlet models designed for optimal performance in wells that allow free travel of floats.

T QED --22 -------------------------------------------------------------------------

. i l

For Low Recovery Wells The QED family of Passive Skimmers has been designed for free product recovery applications in sites where active pumping systems are not applicable due to existing conditions or extreme low permeability formations. The floating intake head follows the groundwater fluctuations in the recovery well, allowing only the free-floating phase (LNAPU to be captured, without taking water, and stored in the built-in reservoir for further manual transfer to a tank.

Passive Skimmers are available for 2" (50 mml and 4" (1 oo mml extraction wells, with different reservoir capacities .

Advantages

1. Simple systems for extreme low recovery applications. 2. Inexpensive option if active system is not practical.

T QED ......._ ...... 26 -------------------------------------------------------------------------

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Canister

Specifications

Model No.

Canister Volume Well Diameter Float Travel Range Overall Length

2 in. SOS 301079 20 oz. 1600 eel 2 in. 15 em) 12 in. 130 em) 65 in. 1165 em)

LNAPL Fluid Density Kinematic Viscosity

@50 F (10 C) Recommended Initial LNAPL Layer

Residual LNAPL Layer Suitable Types of LNAPL

Materials

2 in. SOS 301080 30 oz. 1900 eel 2 in. 15 eml 12 in. 130 eml 48 in. 1122 eml

< 1.0 SG

200 centistokes > .25 in. I> .64 eml 0.25 in. (.64 eml Gasoline, jet fuel

4 in. SOS 301032 101 oz. 13,000 eel 4 in.noeml 18 in. 146 eml 119 in. 1302 eml

Stainless steel, Vitone, PVC, brass, closed cell foam.

4 in. SOS 301033 203 OZ. 16,000 eel 4 in. no emil 18 in. 146 eml 11 in. 128 em!

Viton IS reg1stered trademark of DuPont Dow Elastomers.

--~ Characterize Your Specific Site The QED Test Kit enables you to measure the density and viscosity of your actual floating hydrocarbon layer. This FREE, do-it-yourself kit comes complete with simple, illustrated instructions. Once you have

recorded the results of your hydrocarbon test, QED application specialists will be able to provide expert technical assistance in system design and specification.

---------------------------------------------------------------------------------------- 27

P.O. Box 3726 Ann Arbor, Ml48106 USA 800-624-2026 F 734-995-1170 info@qedenv.com www.qedenv.com

For High Recovery Wells. The AutoSkimmer™ Pump System automatically recovers free product and pumps on demand when the pump is filled, combining the industry-leading AutoPump® with the rugged SPG floating inlet. The system can then be switched to higher flow, total fluids pumping by removing the floating inlet. When site conditions call for this approach, nothing beats the AutoPump/ SPG inlet combination; both of these technologies have been proven in the field for many years around the world . The AutoPump mechanism means that the pump cycles only when it is filled with LNAPL, reducing air consumption without adding any additional controls or sensors. The SPG inlet includes selectable side inlet ports for versatility in fine-tuning LNAPL intake when the floating layer is reduced in thickness.

Warranty AutoSkimmers are warranted for one (1) year.

Advantages

1. Unique design allows pump to cycle only when it is completly full of fluid. 2. Versatile design allows floating inlet removal for conversion to total fluids pumping after

the LNAPL is largely eliminated. 3. Air-powered, intrinsically safe. 4. Built-in ON/ OFF control with internal float. 5. Proven reliability and durability.

T QED _,_ 28 -------------------------------------------------------------------------

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Top Inlet Port

Side Inlet Port

SPG Float

Coil

Centralizer Disk

Modified Low Drawdown AP4 AutoPump ®

Specifications

AutoSkimmer Model Short AP4-SPG4 (301243} ' Maximum LNAPL Recovery Rate 320 gpd 11,211 Lpd)

Float Travel Range 16 in. 141 eml Overall Length 78 in. 1198 eml

Minimum Liquid Column 52 in. 1132 cml Pressure Range 5-1 20 psi 10.4-8.5 kg/em'J

High Pressure Option 5-120 psi 10.4-8.5 kg/em'J

Minimum WeiiiD 4 in. 110eml Maximum OD 3.5 in. 18.9 eml

Maximum Depth 200 ft. 160.9 ml LNAPL Fluid Density < .85 SG Kinematic Viscosity 1-1000 centistokes

Recommended Initial LNAPL Layer > 3 in. I> 7.6 em) Residual LNAPL Layer > .25 in. 1.64 eml

Suitable Types of LNAPL Gasoline, diesel, jet fuels, kerosene, #2 -#5 fuel oils, light weight motor oil and hydraulic fluid

Materials Brass, Tygon®, stainless steel, Viton®, Teflon® Fitting Type Quick-connect or barbs

Hose or Tubing Both are available

Tygon is a registered trademark of Sa1nt Goba1n ·Norton. Viton is reg1stered trademark of DuPont Dow Elastomers. Teflon is a registered trademark of DuPont • gpd = gallons per day, Lpd = lrters per day

_._._ Characterize Your Specific Site

The QED Test Kit enables you to measure the density and viscosity of your actual floating hydrocarbon layer. This FREE, do-it-yourself kit comes complete with simple, illustrated

instructions. Once you have recorded the results of your hydrocarbon test, QED application specialists will be able to provide expert technical assistance in system design and specification.

29

P.O. Box 3726 Ann Arbor, Ml48106 USA 800-624-2026 F 734-995-1170 info@qedenv.com www.qedenv.com

APPENDIX B LI-COR C02 EFFLUX SURVEY PROCEDURES

Stantec

APPEN DIX B

Dynamic Closed Chamber (DCC) Field Procedures A. References LI-COR Biosciences. 2005. Ll-8100 Automated Soil COz Flux System Instruction Manual.

LI-COR Biosciences. 2012. LI-8100A Automated Soil COz Flux System - Field Guide.

B. Installation Procedures Installation procedures for soil collars in warm weather (summer) and cold weather (winter) are included in Attachment 1 and 2, respectively. Ground surface preparation procedures for installation of soil collars in especially hard or compacted soil is included in Attachment 3.

Following installation of the soil collars, soil in the area of the collar are recorded and photographed. Before measurements begin, the offset (height of the collar top lip above ground surface) is measured. This measurement is used to estimate the total volume of air inside the chamber and collar and is an important part of the overall efflux calculation. An average value of the offset measured from three sides of the collar are used to estimate it as accurately as possible. Attachment 4 contains sample field data forms that can be used to record the collected field data.

C. Measurement Procedures 1. Install the soil collar.

2. Set up the measurement. The LI -COR controller is set up with the following parameters:

a) Chamber Offset= Average collar height above soil b) Observation Delay= 0 seconds c) Dead band = 20 seconds d)

e)

f)

Observation Rate = 90 seconds Post-purge= 30 seconds Minimum Number of Measurements = 3

3. Place the chamber over the collar.

4. Start the measurement. Enter file name (location I D) and any site-specific comments.

5. Transfer files to a computer.

6. Import the data into the computer program SoiiFiuxPro to evaluate the computation and data reduction.

D. Measurement Description The control unit automatically operates the chamber bellows, pump, and IRGA unit to perform efflux measurements. The pump and IRGA start and initiate a short period of pre-measurement purge. All cycles are controlled using user-definable t imers. Following the purge cycle, the bellows is inflated to close the chamber tight atop the collar. The pump circulates vapor through the chamber and back into the analyzer unit for COz, temperature, and water vapor measurement. The IRGA measures the change in COz concentrations in the vapor return line connected to the chamber.

After a short deadband period, which is the time interval set to allow steady mixing in the chamber after it closes, the analyzer records the change in C02 over time until the pre-set measurement period ends. The water and temperature data are used to correct the measured C02 to a dry standard unit of measure. After the measurement period ends, the bellows deflates, the chamber is raised off the collar, and a post -measurement purge cycle is initiated. This process of bellows inflation, measurement, and bellows deflation continues until the preset number of measurements are co llected at each location. The control unit then stops all function and allows the user to view the data and evaluate whether additional measurements are needed at the same location or whether measurement is complete. When measurements are complete, the user lifts the chamber and analyzer units, and moves to the next location to repeat the process.

E. Quality Assurance I Quality Control Appropriate quality assurance and quality control measures are essential to assess the accuracy and precision of the data collected. Although detailed and robust calibration is completed by most manufacturers of DCC systems under controlled laboratory settings, a span calibration of the instrument in the field is recommended prior to collecting field efflux data. Typically, this involves calibration to a 0-ppm C02 standard and a span gas with a 500-ppm C02 concentration.

A minimum of one duplicate efflux monitoring location per every 10 locations is recommended. The duplicate collar should be installed the same way as the original location and placed no more than approximately 3 feet from the original location, in similar ground cover. Basic statistics including the calculation of a relative percent difference (RPD) from the natural and duplicate sample data are performed to assess data quality. An RPD greater than 30 percent may prompt the user to assess the soil collar installation procedures to ensure a good seal with the subsurface was attained.

Additionally, a field blank is collected during each field event by attaching a closed collar that does not allow gas flow into the chamber. A total of 60 readings are obtained for each field blank.

F. Recordkeeping A suggested field sampling sheet template is included in Attachment 4 . Some of the more important fields on the sampling sheet template include: soil collar installation detai ls (including installation method, date, and weather conditions during installation), calibration results and setup details of the DCC instrument, and measurement data that include date/time, location, average offset measured from three points on the collar, ground cover details, flu x measurement and trace gas concentrations. Documentation of weather conditions is also very important and recorded prior to the start of each measurement at an individual location.

Attachment 1

Summer DCC Collar Installation

Procedures

Summer DCC Collar Installation Procedures A. Purpose To install PVC collars for the collection of efflux measurements using the LI-COR 8100A carbon dioxide (C02) soil flux system including the flux chamber and infrared gas analyzer (IRGA).

B. References LI -COR Biosciences. 2005. Ll-8100 Automated Soil C02 Flux System Instruction Manual.

LI -COR Biosciences. 2012. LI-8100A Automated Soil C02 Flux System - Field Guide.

C. Frequency One collar per sample location installed 12 to 24 hours before data collection, where possible.

D. Location Perform this procedure at designated sampling locations as stated in the work plan. Sampling should encompass locations above contamination and background locations away from contamination. All types of ground surface covers encountered should be included in background and contaminated locations, i.e., gravel, grass, organic, etc.

E. Materials • 8-inch-diameter Schedu le 40 PVC collar designed for LI-COR 8100A survey

• 2-inch by 4-inch Y.-inch-thick plywood

• Rubber mallet • Shovel or small trowel for digging ·

• Tamping device • Wetted cloth (or equal) to form an impermeable seal around the LI-COR flux chamber on the

plywood

F. Preparation and Precautions • Clear all vegetation from the sampling location • Do not install collars in locations prone to flooding, or water pooling during rain .

G. Procedures • Place the collar on the ground, and insert as far as you are able.

• Place a foot-long piece of 2x4 wood on top of the collar and using a mallet; hammer the collar 2 to 5 em into the ground. If soil conditions prevent advancement of the collar, an alternative method of installation using a shallow excavation as documented in Attachment 3 can be used.

• Re-compact any disturbed soil. Lift the tamping device so it is in line with the top of the collar, and drop. Do no use any extra weight or force. Repeat three times. See the Attachment 3 for further details regarding ground surface preparation.

H. Quality Assurance and Corrective Action Collection photo documentation of each collar location and review historical documentation to ensure that the locations are consistent and/ or are as expected.

• If there is a rain shower, allow 2 hours for the water to drain from the collar prior to completing data collection

• If vegetation happens to collect in the collar after installation, remove prior to completing data collection

Attachment 2

Winter DCC Collar Installation

Procedures

Winter (Sub-zero) DCC Collar Installation Procedures A. Purpose To install PVC collars for the collect ion of efflux measurements using the LI-COR 8100A carbon dioxide (C02) soil flu x system including the flux chamber and infrared gas analyzer (IRGA) where soil conditions are frozen and impenetrable to the standard collar installation method.

B. References LI-COR Biosciences. 2005. Ll-8100 Automated Soil C02 Flux System Instruction Manual.

LI-COR Biosciences. 2012. LI-8100A Automated Soil C02 Flux System- Field Guide.

C. Frequency One collar per sample location insta lled 12 to 24 hours before data collection, where possible.

D. Location Perform this procedure at designated sampling locations as stated in the work plan. Sampling should encompass locations above contamination and background locations away from contamination. All ground surface covers should be included in background and contaminated locations, i.e., gravel, grass, organic, etc.

E. Materials • 8-inch-diameter Schedule 40 PVC collar designed for LI-COR 8100A survey

• 2-inch by 4-inch %-inch thick plywood

• Rubber mallet

• Shovel or small trowel for digging

• Tamping device

• Wetted cloth (or equal) t o form an impermeable seal around the LI-COR flux chamber on the plywood

F. Preparation and Precautions • Clear all snow and ice from sampling location • Clear all vegetation from the sampling location

G. Procedures • Place the collar on the ground, and insert as far as you are able using hand tools.

• For solid frozen surfaces, simply score a shallow (<1 em) rut in which the collar can sit .

• For field temperatu res consistently sub-zero (Figure 1} - Place a wet (not dripping) cloth (J-cloth) around the base of the outside of the collar. Try to ensure that water from the cloth does not run into the inside of the collar.

• After the cloth freezes and sets around the collar, pour a small amount of water on it to form a continuous ice seal all the way around the collar. Ensure all gaps between the ground and collar are filled and let the cloth freeze.

H. Quality Assurance and Corrective Action • Collection photo documentation of each collar location and review historical documentation to

ensure that the locations are consistent and/or are as expected.

• Do not perform field monitoring if the temperature falls below -20 °C. The unit is not rated for lower tern peratu res.

• If it snows after the collar is installed, remove as much as possible from the collar prior to completing data collection

• If vegetation happens to collect in the collar after installation, remove prior to completing data collection

• Before collecting data ensure the IRGA is up to temperature. It will collect data when it is not up to temperature, but it will be no good. A red light bulb will illuminate on the control panel when the IRGA reaches its proper temperature set-point, do not proceed until it is lit.

I r / '

Figure 1- Below-zero Degrees Celsius Collar Installation

Attachment 3

Ground Surface Preparation

Procedures

Ground Surface Preparation Procedures ­Soil Collar/Receiver Pipe A. Purpose and Scope The purpose is to provide general guidelines for the compaction of soils in and around the soil vapor efflux measurement pipe and soil co llars associated with carbon dioxide (C02) efflux measurement systems such as passive flux traps and the DCC soil flux system. This procedure is strictly related to the placement and re-compaction of soil removed as part of the pipe and co llar installation into the sha llow ground surface (i .e., less than 4 inches depth). Attachment 4 contains sample field data forms that can be used to record information about pipe and collar installation and soil compaction.

B. References LI-COR Biosciences. 2005. Ll-8100 Automated Soil COz Flux System Instruction Manual.

LI-COR Biosciences. 2012. LI-8100A Automated Soi l COz Flux System - Field Guide.

C. Equipment and Materials • Hand trowel • 3-inch curved carpet knife

• 5-gallon bucket(s) and/or plastic sheeting for soil storage

• Kevlar or cut-resistant gloves • ASTM D-698 Standard Proctor Compaction Hammer (5.5 lbs. with 12-inch drop)

• Field logbook

D. Procedures and Guidelines

A. Excavation and Preparation for Backfilling

It is generally preferred to directly push the pipe and collar into the ground. This can be performed using manual or hammer means. However, some more difficult soil conditions require a concurrent method of soil removal (excavation) and direct push. The following guidelines are provided to support a higher quality installation using either direct push or excavation means.

1. If soil is saturated, pipe/ colla r should not be installed and soil must be allowed to drain/ dry out after a rain event prior to installation.

2. Manually remove surface and shallow vegetation from installation location to minimize background COz influence. If roots are encountered during excavation, remove and discard them.

3. During sha llow excavation activities to accommodate the insertion of t he soil vapor efflux measurement pipe/collar, excess soils removed shou ld be placed in a 5-ga llon bucket or on plastic sheeting adjacent to the work area. This is done to segregate the soil removed in order to only replace the soi ls that were removed initially.

4. Following insertion of the pipe or collar, and prior to backfilling, the field personnel should measure the depth from the ground surface to the bottom of the pipe (i.e., the depth of the excavation).

5. If the excavation depth exceeds 4 inches, the backfilling will require placement of two separate soil lifts of equivalent thickness (e.g., if the excavation is 6 inches deep, the backfill is replaced and compacted in two separate 3-inch-thick lifts).

6. All large particles (i.e., anything 3 inches or larger in diameter) should be set aside and not replaced in the excavation. Large particles such as rocks, will inhibit the ability to adequately compact smaller soil particles and may result in nesting or voids below these larger particles. Additional smaller particulate materials may be gathered from surrounding soil for replacement, if required.

7. If, during initial excavation, it is determined that greater than 50 percent of the soil removed consists of large particles (i.e., those particles greater than 3 inches in diameter), AND those conditions appear to match the surrounding soil conditions, all materials should be selectively replaced in lifts to match the thickness of the largest particle and compacted per instructions provided below.

8. During removal, if soils are mostly clay/silt, it will be important to break up clods larger than 2 inches in diameter before materials are backfilled. This can be done by use of the hand trowel in the 5-gallon bucket or on the plastic sheet.

B. Backfilling and Compaction

Once the soil vapor efflux measurement pipe or collar has been installed using either direct push or excavation means, the process of replacing the soils within the area inside and outside the pipe or collar can begin and those soils can be compacted to closely match the surrounding soil conditions based on the field observations.

1. Using the hand trowel, replace the soil from the 5-gallon bucket or the plastic sheeting in an even horizontal loose lift to the maximum allowable thickness indicated in Section A above across the entire area (i .e., both inside the pipe and outside the pipe).

2. Begin compaction of the inside of the pipe first. Start in the center. Place the hammer sleeve in the center of the pipe with the hammer resting on the ground. Firmly hold the sleeve in­place and lift the hammer (via the ball on the top) to maximum height (12 inches) and allow the hammer to free fall. Lift the sleeve and note the amount of indentation to the soil surface in the field book. Move carefully around the initial compaction spot by systematically moving the sleeve to an adjacent uncompacted spot and repeating the hammer drop gradually moving toward the pipe sidewall. Continue moving the sleeve and dropping the hammer until the entire surface area of the soil inside the pipe has been compacted with one hammer blow.

3. Move to the disturbed soil outside of the pipe. Start at the outside sidewall of the pipe, repeat the compaction process described in Step 2 moving around the pipe fi rst and covering the area toward the outside edge of disturbed soil. Continue until the entire area of disturbed soil outside of the pipe has been compacted with one hammer blow.

4. Move back to the center of the pipe and only perform one hammer drop at that location. Do not continue to compact soils inside pipe at this time. After the hammer drop, stop and note the amount of indentation to the surface in the field book.

5. Move to an area outside of the area that was previously excavated (an area of undisturbed soil), but contains soils that are similar to those in the excavated area. Perform one hammer drop on the ground surface in the undisturbed area and note the amount of indentation to the ground surface in the field book.

6. If the indentations from Step 4 and Step 5 are equal or the indentation in Step 4 is less than the indentation in Step 5, no further compaction of t he soil inside the pipe and the disturbed soil outside the pipe is necessary and t he second loose lift of soil (if required) can be placed and compacted per Step 2.

7. If the indentation in Step 4 is greater than the indentation in Step 5, repeat Step 2 on the same lift both inside and outside the pipe. When completed, repeat Step 4 and compare to the indentation recorded for Step 5.

8. Upon replacement of all soils from the 5-gallon bucket and/or plastic sheeting, the backfilling process is considered complete. No additional soils should be added.

The primary function is to replace the soils in and around the pipe to closely match the surrounding in­place soils. This SOP focuses on lift thickness placement (i.e., a thin level lift that is placed loose) and the number of tamps used to compact the soils to closely match the su rrounding soil conditions.

E. Key Checks and Preventative Measures • Keep 5-gallon bucket(s) and/or plastic sheeting close to excavation area to avoid long reach and

limit repetitive bending at the waist.

• If using only plastic sheeting, be sure to segregate soil piles from separate pipe locations and note which pipe location goes with which soil pi le. Similarly, the 5-gallon bucket shou ld be used for only one pipe excavation at a time. Do not comingle excavation soils in one bucket.

• After each pipe installation, be sure to stand and stretch. Avoid repetitive bending for periods longer than one round of compaction work.

• Keep the working space clean with plastic sheeting and good housekeeping.

• Maintain field equipment in accordance with the manufacturer's recommendations.

• This will include, but is not limited to:

Inspect compaction hammer and replace as warranted Inspect excavation devices and replace as warranted

Attachment 4

Field Forms

Soil C02 Efflux Measurements

Dynamic Closed Chamber Method Field Log

Site location: Temperature: Date:

Project Number: ~W~l~nd~:~-------------------------------------------- Page ___ of __ _

Project Manager: Skies:

Field Personnel: Location 10:

I soil Collar Installation Details

Date Installed: Offset (em):

Install Method: Soli Conditions:

Measurement Data

Date/Time of Collection Treatment New/ Observation Observation

#OBS Weather Flux Label Appending File Delay Rate

Comments

C02 Trap Field Log Site Location: Project Number:

Project Manager: Temperature:

Field Personnel: Wind:

Skies:

I Location ID I Date Installed I Time Installed I Date Removed I Time Removed I Comments I

APPENDIX C EFLUX C02 TRAP PROCEDURES

Stantec

E o FLUX

STANDARD OPERATING PROCEDURE:

C02 TRAP DEPLOYMENT AND REPLACEMENT

PROTOCOL

For questions contact:

Julio Zimbron, Ph.D. E-Fiux, LLC

3185-A Rampart Road, Room 2500 Fort Collins. CO 80521

o: (970) 492 4360 c: (970) 219-2401

jzimbron@soilgasflux.com

Last modified: July 13, 2015.

Proprietary and Confidential Information

© 2014 All Rights Reserved.

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

INTRODUCTION

©201 4 All Rights Reserved Page 2

The following document describes protocols for deployment of COz traps in support of studies to evaluate rates of natural

attenuation of light non-aqueous phase liquid hydrocarbons (LNAPL). The document includes a list of too ls requ ired for

deploying the traps. Material Safety Data Sheets (MSDSs) for the sorbent media in the traps, and the lubricant to be used

on the receiver ends are available upon request.

The traps are filled with a proprietary non-hazardous C02 sorbent, consisting of a mixture of calcium and sodium

hydroxides (strong bases). Thus, caution should be used when handling traps. The sorbent media is contained within the

traps and should not pose a direct contact hazard as long as the traps are not damaged and are handled with care.

Personal protective equipment selection for handling the media is defined in the MSDSs. As a minimum, the use of nitrile

gloves beneath leather work gloves and safety glasses when handling the fu lly assembled traps is recommended.

EQUIPMENT LIST

1) SOP (this document), MSDS sheets for C02 Sorbent and and lubricant gel.

2) Site maps.

3) C02 trap shipment and installation log - will be shipped with traps from E-Fiux.

4) Appropriate PPE (not provided, to be determined by site contractor).

5) C02 trap receivers- to be installed at the site previous to first trap deployment. Receivers will stay at the site until last planned sampling event is complete.

6) C02 trap rain covers.

7) COz Traps- W ill be shipped to the Site by E-Fiux.

8) Diffusion cap- These should remain onsite between sampling rounds.

9) Flathead screwdriver, or nut driver tool (Not provided) to remove ring clamp from top rubber shipping cap.

1 0) Temperature Loggers (optional) .

NOTE: All shipments include a contents list. If shipment contents do not match list, do not proceed to installation and

contact E-Fiux immediately.

Figure 1. COz trap (shown capped}, receiver pipe, connector and rain cover.

{ L

l

l

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SOP: Receiver Pipe Installation Guide

GENERAL PLACEMENT GUIDELINES

©201 4 All Rights Reserved

Page 3

• It is recommended that trap locations are near existing groundwater monitoring wells. This is important for data

discussion and correlation of C02 fluxes to known geologic, hydrogeologic, and hydrocarbon distribution

conditions.

• Suitable trap locations require soils that are permeable to gas transport. Pavement or low permeability surface covers (including free standing water, ice, or extremely compacted soils) should be avoided.

• In some sites, variability within close locations due to soil heterogeneity can be large. If testing for variability,

replicate traps should be located within 10 feet of each other.

• Excess surface vegetation should be cleared from directly beneath the proposed trap location prior to installation of the in-ground receiver.

• If desired, background locations (unimpacted) should be chosen where soils, vegetation, and general site conditions are similar to the LNAPL monitoring locations.

• Additional site data that might be useful for data discussion includes:

1. Groundwater temperatures. Due to the exotherminc nature of biodegradation, in some cases groundwater temperatures have correlated to biodegradation rates estimated based on soil gas fluxes (McCoy, et al ,

2014).

2. Soil gas concentration profiles at discrete vadose zone locations or in well headspace (Wilson et al , 2013) might reveal high C02 and/or methane concentrations and thus be indicative of areas of high rates of

LNAPL degradation.

3. Groundwater and LNAPL levels in wells (if applicable).

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IN-GROUND RECEIVER INSTALLATION

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This section describes the standard operating procedure, suitable for temporary monitoring points in most uncompacted

soils. If soils are compacted and/or monitoring locations are intended to be permanent (i.e. , for long term monitoring), users should review accompanying document "Guideline for Alternative In-Ground Receiver Installation for Long Term Monitoring and/or Compacted Soils". For standard In-Ground Receiver Installation:

1) Ensure that vegetation is removed from the trap installation location.

2) Tighten the eye screws through the U-nuts placed on the receiver

3) Place receiver in ground. Keeping the receiver vertical push the receiver using a rubber mallet and the provided direct push tool.

4) Hammer the stakes through the eye screws on a 45° angle.

5) Compact soil to achieve compaction as close as possible to pre-installation conditions .

.. Figure 2. In-ground Receiver Installation (Steps 2-5)

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SOP. Receiver Pipe Installation Guide

RECOMMENDATIONS FOR DEPLOYMENT

©201 4 All Rights Reserved

Page 5

• To avoid trap saturation or non-detectable measurements (due to extreme high or low C02 fluxes, respectively) , field traps shall be deployed as determined during project planning. A typical deployment period of 2-weeks is sufficient for most common C02 flux ranges of interest.

• One Trip Blank is included with each batch of traps. This trap should not be opened. It will remain at the Site and must returned to E-Fiux with the other traps after the sampling Period.

• KEEP TRAPS UPRIGHT.

• Traps contain caustic material, use caution when handling. Avoid unnecessary shaking or abrupt movements.

• Sorbing material is moisture resistant, but not water proof. Keep traps dry and avoid unecesssary moisture.

TRAP DEPLOYMENT PROCEDURE

A shipment and installation chain of custody (COC) form (field log) will be shipped with the traps. The COC should be

filled out with the date and time that each trap is installed and removed for return. A period of one day is recommended between installation of the receiver pipe and trap deployment, to allow for soil equilibration after disturbance.

1) Find the appropriate trap for the location (ref. site map).

2) Carefully slide connector onto the installed receiver pipe. Using a flat head screwdriver tighten the bottom clamp.

3) Unscrew top and bottom caps off the C02 Trap (set caps aside as these will be needed for shipping the traps back to E-Fiux).

4) Screw rain cover onto the top side of the C02 Trap (keep trap upright).

5) Carefully slide C02 Trap into the connector. Using a flat head screwdriver tighten the top clamp on the connector.

6) Place Identification label on the connector.

Figure 3. In-ground Receiver Installation (Steps 1 ,3,4,6-8).

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SOP. Receiver Pipe Installation Guide

RETURNING TRAPS TO E-FLUX

©2014 All Rights Reserved

Page 6

1) At end of monitoring period, reverse steps. Place a small amount of lubricant on the PVC shipping plug before inserting back into bottom of the trap. The bottom cap (PVC) should slide in the bottom of the trap with relatively little effort. The top cap (rubber) should be put after the bottom one. Note date and time removed from ground on the log. Place the log in dry cooler with traps. The traps have stored the C02 in a stable form (as carbonates)- the best way of handing them is by keeping the traps dry. Other means of preservation (such as ice or refrigeration) are not necessary (nor desirable). 2) Ship to E-Flux in dry coolers. Keep traps upright. Notify E-Fiux of tracking number after shipping to the following

address:

E-Fiux, LLC

Julio Zimbron, Ph.D. 3185-A Rampart Road , Room 0257 Fort Collins, CO 80521 office: (970) 492-4360 cell : (970) 219-2401

Attn: Julio Zimbron Email: jzimbron@soilgasflux.com

E o FLUX

STANDARD OPERAT ING PROCEDURE:

Receiver Pipe Inst allat ion Gu ide

For questions contact: Julio Zimbron, Ph.D.

E-Fiux, LLC

3185-A Rampart Road, Room 2500

Fort Collins, CO 80521 o: (970) 492 4360 c: (970) 219-2401

jzimbron@soilgasflux.com

Last modified: July 8, 2015

Proprietary and Confidential Information

© 2014 All Rights Reserved.

Proprietary and Confidential Information

SOP. Receiver Pipe Installation Guide

INTRODUCTION

©2014 All Rights Reserved

Page 2

The following document describes protocols for installation of receiver pipes for E-Fiux C02 traps. C02 traps are instal led

to evaluate rates of natural attenuation of light non-aqueous phase liquid hydrocarbons (LNAPL) in soil. Since the C02 traps measure flux of C02 coming out of the soil surface, it is necessary to install them in the ground via a receiver pipe

with a secure seal. This document presents several alternatives for receiver pipes and describes procedures for

installation of each one. A list of tools required for each method of installation is provided. Upon review of this document,

the user will be able to choose the installation method that is best suited for the site.

GENERAL PLACEMENT GUIDELINES

• It is recommended that trap locations are near existing groundwater monitoring wells. This is important for data

discussion and potential correlation of C02 flu xes to known geologic, hydrogeologic, and hydrocarbon distribution conditions.

• Suitable trap locations require soils that are permeable to gas transport. Pavement or low permeability surface covers

(including free standing water, ice, or extremely compacted soils) should be avoided.

• In some sites, variability within close locations due to soil heterogeneity can be large. If testing for variability, replicate

traps should be located within 1 0 feet of each other.

• Excess surface vegetation should be cleared from directly beneath the proposed trap location prior to installation of the in-ground receiver.

• If desired, background locations (unimpacted) should be chosen where soils, vegetation, and general site conditions are similar to the LNAPL monitoring locations.

• Additional site data that might be useful for data discussion includes:

1. Groundwater temperatures. Due to the exotherminc nature of biodegradation, in some cases groundwater

temperatures have correlated to biodegradation rates estimated based on soil gas fluxes (McCoy, et al ,

2014).

2. Soil gas concentration profiles at discrete vadose zone locations or in well headspace (Wilson et al , 201 3)

might reveal high C02 and/or methane concentrations and thus be indicative of areas of high rates of

LNAPL degradation.

3. Groundwater and LNAPL levels in wells (if applicable).

Proprietary and Confidential Information

SOP. Receiver Pipe Installation Guide

GENERAL NOTES

• Keep traps upright.

• Typical deployment period is 2 weeks.

• If traps deployed for -1 week and rain, pull out.

• Avoid saturated soil (w/standing water) .

• Traps are moisture resistant but, not water proof.

• Sample preservation not needed.

• Shipping next day optional.

• Travel blank handling.

©2014 All Rights Reserved

Page 3

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

INSTALLATION METHODS

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Several different methods for receiver pipe installation are available. Choosing a method depends on characteristics of soil present at the site, the desired installation period, and the propensity for trap disturbance (i.e. a cow kicking the trap over). Table 1 gives an overview of each method.

Table 1: Installation Methods

Option Receiver Seal

Advantages Disadvantages When to Install Depth Strength

• easier /quicker • might lose the seal if

• softer soils (few cobbles) disturbed

Direct 2 in Medium

installation • might require

• shorter installation Push • minimal soil

reinstallation with each periods (no more than 4

disturbance trap deployment rounds of samples)

• larger sampling • requires more materials • sites with previously surface area for installation installed chamber collars

8" Collar • minimal soil • might lose the seal if • for comparison with + 2 in Medium disturbance disturbed chamber methods

Reducer • Larger • might require re- • when a larger sampling area/perimeter ratio installation with each area is desired (less prone to leaks) trap deployment • soils with cobbles(- 1 in)

• placement • sites where trap

disturbance is a concern 10 in underground allows • longer installation time

(i .e. areas with human At Grade

(housing High

for minimal • complex installation traffic) +trap environmental and/or procedure depth) human disturbance • disturbs soil

• long installation periods

• minimal visual impact (more than 4 rounds of samples)

• longer installation time • soils with sand or gravel

Hole + • deep secure lasting • requires careful • long installation periods Backfill

7 in High seal

recompaction to (more than 4 rounds of

minimize soil disturbance

samples)

• long lasting secure • soils with sand or gravel Concrete 7 in High

seal • longer installation time • long installation periods Ring • permanent sampling • disturbs the soil (more than 4 rounds of

port samples)

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©2014 All Rights Reserved

Page 5

The direct push method involves hammering a beveled receiver pipe about 2 inches into the soil. This method is good for temporary monitoring in soils that once disturbed might not be recompacted back to their original condition. Soil disturbance is minimized with this method, reducing the possibility of interfering with soil gas transport by receiver pipe installation.

This method offers minimal stability to the receiver pipe, so the seal achieved is only adequate for a short term (no more than 4 sampling events). A rubber connector with hose clamps is used to attach the receiver pipe to the C02 trap so that disturbance to the seal between the receiver pipe and soil is minimized. A knife can be used to cut a ring into the soil that the beveled receiver is placed into. This groove eases installation and can help create a deeper seal without completely digging out and disturbing the soil.

Option Depth Seal

Advantages Disadvantages When to Install Strength

• easier /quicker • might lose the seal if • softer soils (few cobbles) disturbed Direct

2 in Medium installation

• might require • shorter installation Push • minimal soil

reinstallation with each periods (no more than 4

disturbance trap deployment rounds of samples)

receiver pipe push tool rubber connector C02 trap rain cover

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

PROCEDURE

Cut a ring with the same diameter as the receiver pipe in the soil with a knife for easier and deeper installation (optional).

Place the beveled side of the receiver pipe vertically on the ground.

Place the push tool on top of the receiver.

Hammer into the ground with the rubber mallet or slide hammer. Keep the receiver vertical.

Remove the push tool off the receiver pipe.

Loosen bottom hose clamp.

PI aCe the conector over the receiver pipe.

Add-on Security. go to page 17 to see ad d-ons for this method.

Trap installation. go to page 15 to see trap installation guide.

bottom hose clamp

©2014 Al l Rights Reserved Page 6

push tool

rubber connector

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

©2014 All Rights Reserved Page 7

The 8" collar method is an adaptation for sites that already have 8" collars installed for

use with the chamber method. Installation involves mounting the reducer between the

collar in the soil and the COz trap. This method is qu ick if collars are already installed in

the soil.

This method allows the trap to collect gas over a large sampling area. 20 em (8 inch)

collars can be installed with the push method if a larger sampling footprint is desired.

Option Depth Seal

Strength

8" Collar + 2 in Medium

Reducer

EQUIPMENT

~ ~

8 inch collar

Advantages

• larger sampling surface area

• minimal soil disturbance

• Larger area/perimeter ratio (less prone to leaks)

//screw V driver

8" x 4" reducer

Disadvantages When to Install

• sites with previously • requires more materials for installed chamber collars

installation • for comparison with

• might lose the seal if chamber methods disturbed

• when a larger sampling • might requ ire re-installation area is desired

with each trap deployment • soils with cobbles (- 1 in)

C02 trap rain cover

Proprietary and Confidential Information

SOP. Receiver Pipe Installation Guide

PROCEDURE

Locate the already installed 8" collars

If 8" collars have not been installed go to direct push method on page to see installation guide.

Loosen bottom hose clamp on reducer.

Place the 8" end of the reducer over the 8" collar.

Tighten hose clamp 2 around the 8" collar.

Add-on Security. go to page 17 to see add-ons for this method.

Ready for trap installation. go to page 1s to see trap installation guide.

©2014 All Rights Reserved

Page 8

8 inch collar

8" x 4" reducer

bottom hose clamp

8 inch collar

Proprietary and Confidential Information

SOP. Receiver Pipe Installation Guide

At grade installation is for situations where C02 trap disturbance is a primary concern. For this method a large hole is dug so that the receiver pipe is put in the ground at a depth of 11 inches. Rain cover is placed over the top of the trap and backfilled so that the trap is essentially underground. A perforated lid is placed over the top of the housing so that t he trap cannot be tampered with.

This installation method is preferable only for sites that might experience significant trap disturbance (such as places open to pedestrian traffic). This method can result in soil disturbance.

©2014 All Rights Reserved

Page 9

Option Depth Seal

Advantages Disadvantages When to Install Strength

10in (housing At Grade

+trap High

depth)

receiver pipe push tool

• placement underground allows • longer

• sites where trap disturbance for minimal installation t ime environmental • complex

is a concern (i.e. areas with

and/or human installation human traffic)

disturbance procedure • long installation periods (more

• minimal visual • disturbs soil than 4 rounds of samples)

impact

l T diggi_ng and •· push

1mg

1 too s

rubber connector CO2 trap flush-J1.1ount housmg

Proprietary and Confidential Information

SOP. Receiver Pipe Installation Guide

PROCEDURE

Place the beveled side of the receiver pipe vertically on the ground.

Place the push tool on top of the receiver.

Hammer into the ground with the rubber mallet or slide hammer. Keep the receiver vertical.

Remove the push tool off the receiver pipe.

Loosen bottom hose clamp.

PI aCe the con ector over the receiver pipe.

Trap installation. go to page 1s to see trap installation guide.

Place the flush-mount housing around the installed trap.

Backfi II the annular space rain cover back to original grade.

©2014 All Rights Reserved

Page 10

Proprietary and Confidential Information

SOP: Receiver Pipe Installation Guide

The hole+ backfill option can be used for temporary monitoring in most uncompacted soils (i.e. sandy soils, vegetated areas). This method involves digging a hole to a depth of 7 inches and backfilling around the receiver pipe. This ensures that the receiver pipe maintains a secure and lasting seal with the surrounding soil. Backfilling needs recompaction to original conditions to avoid disturbing gas transport processes.

Although this method is simple to implement and a good choice for most situations, it might result in soil disturbance and should not be used if recompaction to original conditions cannot be accomplished (i.e. if there is a highly compacted clay layer within the excavation depth).

©2014 All Rights Reserved

Page 11

Option Depth Seal Advantages Disadvantages When to Install Strength

• longer installation time • soils with sand or gravel Hole+

? in High • deep secure • requires careful • long installation periods Backfill lasting seal recompaction to minimize (more than 4 rounds of

soil disturbance samples)

EQUIPMENT

I.

l T digging an~ . recompact1on

\ 1 tools

receiver pipe rubber connector C02 trap rain cover

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

PROCEDURE

Dig a hole approximately 7-inches deep.

Place receiver vertically in ground, with anchoring brackets down.

Backfill the annular AND internal space of the in-ground receiver back to original grade.

Compact soil within the annular AND internal space of the in-ground receiver with hand tools to achieve compaction as close as possible to original soil conditions.

Trap installation. go to page 1sto see trap installation guide.

+ - t--

receiver pipe

©2014 All Rights Reserved Page 12

receiver pipe

brackets

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

©2014 All Rights Reserved Page 13

The concrete ring method provides the most stability to the receiver pipe (suitable for

long term use). The PVC receiver pipe is installed using the same procedure as the hole

+ backfill option but is secured with concrete after backfilling.

This method ensures that the receiver pipe will not move or shift, achieving a seal

stable for long periods. Since this method is permanent, it is recommended for long

installation periods (multiple rounds of sampling).

Option Depth Seal Strength

Concret 7 in High e Ring

receiver pipe

Advantages

• long lasting secure seal

• permanent sampling port

YT digging and J reco.mpaction '1 tools

C02 trap

Disadvantages When to Install

• longer installation • soils with sand or gravel

time • long installation periods

• disturbs the soil (more than 4 rounds of samples)

rain cover concrete

cooqct>.

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

PROCEDURE

Dig a hole approximately 7-inches deep.

Place receiver vertically in ground, with anchoring brackets down.

Backfi II the annular AND internal space of the in-ground receiver back to original grade.

Backfill the internal space of the in-ground receiver back to original grade.

Compact soil within the annular AND internal space of the in-ground receiver with hand tools to achieve compaction as close as possible to original soil conditions.

Fill the 2 inch annular space around the in-ground receiver with concrete back to original grade.

Ready for trap Installation. go to page 1sto see trap installation guide.

receiver pipe

©2014 All Rights Reserved Page 14

receiver pipe

brackets

Proprietary and Confidential Information SOP: Receiver Pipe Installation Guide

TRAP INSTALLATION

©2014 All Rights Reserved Page 15

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

EQUIPMENT

//scr_ew ~ dnver

in~talled rece1ver p1pe

D PROCEDURE

SELECT the trap to be deployed. WRITE information on the installation log

REMOVE top cap off the trap.

i:W#I!IF3

SCREW trap into the rain cover.

t

©2014 All Rights Reserved Page 16

C02 trap rubber conector

rain cover

0

EJ REMOVE bottom cap off the trap.

SLIDE trap onto the rubber conector. (carefully)

PLACE identification label on the rubber conector .

SLIDE trap onto the installed receiver pipe. CAREFULLY tighten the conector's top and bottom clamps

=>

i§I#I!IF:i

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

AD D-ONS

©2014 All Rights Reserved Page 17

Proprietary and Confidential Information SOP Receiver Pipe Installation Guide

STABILIZING TENSORS

//screw V driver

receiver pipe

TharTlmering tools

hose clamp

Slide u-nuts into the hose clamp.

Slide hose clamp with u-nuts on the receiver pipe.

Tighten the hose clamp around the receiver pipe.

Tiqhten the eye screws through and the u-nuts

Hammer the stakes through the eye screws on a 45° angle.

u-nuts eye screws

I

©201 4 All Rights Reserved Page 18

stakes

~ u-nuts

hose clamp ..__ ____ ___,[§!