OPERATION AND MAINTENANCE PLAN Art Brass Plating Interim Cleanup Action Prepared for: Art Brass Plating Inc.

Project No. 050067-006 May 21, 2010

401 Second Avenue S, Suite 201 Seattle, WA 98104 Tel: (206) 328-7443 Fax: (206) 838-5853 www.aspectconsulting.com

a limited liability company

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Contents

1  Introduction ................................................................................................. 1 1.1  Background .................................................................................................. 1 1.2  Site Health and Safety ................................................................................. 1 1.3  Spill Prevention Control and Countermeasures ........................................... 1 1.4  Operation and Maintenance Contacts ......................................................... 2 

2  Remediation System Description .............................................................. 3 2.1  Soil Vapor Extraction System ....................................................................... 3 2.2  Air Sparge System ....................................................................................... 3 2.3  Soil Vapor Extraction/Air Sparge Interaction ................................................ 4 2.4  220 Findlay Vapor Mitigation System .......................................................... 4 

3  Remediation System Operation ................................................................. 5 3.1  Operational Monitoring ................................................................................. 5 

3.1.1  Monitoring Parameters ........................................................................... 6 3.1.2  Monitoring Procedures ........................................................................... 6 3.1.3  Evaluation of Operational Monitoring Data ............................................ 7 3.1.4  Contingency Actions based on Operational Monitoring ....................... 10 

3.2  Soil Vapor Migration Monitoring ................................................................. 11 3.2.1  Soil Vapor Monitoring Parameters ....................................................... 11 3.2.2  Evaluation of Soil Vapor Monitoring Data ............................................ 11 3.2.3  Contingency Actions based on Soil Vapor Monitoring ......................... 12 

3.3  Groundwater Monitoring and Sampling ..................................................... 12 3.3.1  Groundwater Monitoring Locations ...................................................... 13 3.3.2  Groundwater Monitoring Methods and Parameters ............................. 13 3.3.3  Evaluation of Groundwater Monitoring Data ........................................ 14 3.3.4  Contingency Actions based on Groundwater Monitoring ..................... 14 

4  Remediation System Maintenance .......................................................... 15 4.1  Housekeeping ............................................................................................ 15 4.2  Equipment Maintenance ............................................................................ 15 

4.2.1  Air Sparge Wells .................................................................................. 15 4.2.2  Soil Vapor Extraction Piping ................................................................ 16 4.2.3  Soil Vapor Extraction Blower ............................................................... 16 4.2.4  Moisture Separator .............................................................................. 17 4.2.5  Moisture Separator Pump .................................................................... 17 4.2.6  Air Sparge Compressor ....................................................................... 17 4.2.7  Heat Exchanger and Ventilation Fans ................................................. 17 4.2.8  Condensate Storage Tank ................................................................... 17 

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4.2.9  Granular Activated Carbon Units ......................................................... 18 4.3  Ecology Notification ................................................................................... 18 

5  Reporting .................................................................................................... 19 

6  Revisions to the O&M Plan ....................................................................... 19 

References ......................................................................................................... 20 

Limitations ......................................................................................................... 20 

List of Tables 1 System Operation and Performance Monitoring Schedules

2 Soil Vapor and Groundwater Monitoring Locations and Analyses

List of Figures 1 Remediation and Monitoring Well Locations

2 Remediation System Layout

3 Remediation System Process and Instrumentation Diagram

List of Appendices

A SVE/AS System Manual (H2Oil Equipment Recovery)

B Vapor Mitigation System Construction and Startup Report 220 South Findlay Street

C Field Monitoring Forms

D Standard Operating Procedures

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1 Introduction

1.1 Background Art Brass Plating (ABP) is located at 5516 3rd Avenue South, in the Georgetown neighborhood of Seattle, Washington. Since 1983, the facility has operated exclusively for metal plating and related work (e.g., metal polishing and powder coating). A facility map showing locations of various operations is provided on Figure 1.

In 2005, ABP conducted a preliminary investigation to evaluate whether volatile organic compounds (VOCs) detected in nearby groundwater had originated from the ABP facility. The results of this investigation confirmed a probable release of trichloroethylene (TCE) from a vapor degreaser formerly located at the ABP facility.

Since the discovery of VOCs in the groundwater, ABP has undertaken a number of investigations to identify the extent of the VOC plume, mitigate the plume, and control future migration offsite, including the installation of a combined soil vapor extraction (SVE) and air sparge (AS) system as the interim cleanup action for the site.

This Operation and Maintenance (O&M) Plan has been prepared for the combined SVE and AS system operating as the interim cleanup action at the ABP facility. This plan was prepared as required by the Washington State Department of Ecology (Ecology) Agreed Order No. DE5256, Section 5.c. and Exhibit B. Documentation of the SVE/AS system construction, including as-built information and startup monitoring, can be found in the Construction and Startup Report (Aspect Consulting, 2008a).

1.2 Site Health and Safety Prior to performing work onsite, operating personnel must review and be familiar with emergency response procedures outlined in the site-specific Health and Safety Plan (Aspect Consulting, 2008b).

1.3 Spill Prevention Control and Countermeasures The primary spill potential from the system is a release of condensate from the moisture separator or condensate tank. However, the SVE system does not generate a significant volume of fluids and both the moisture separator and condensate tank are located in secure areas (the roof to the ABP building and a fenced enclosure). In the unlikely event that either the moisture separator or the condensate were breached, they are both equipped with adequately sized secondary containment to contain the volume of liquid that would potentially escape.

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1.4 Operation and Maintenance Contacts Full time operating personnel are not required for the operation of the SVE/AS system. During the course of the system’s lifetime, it is anticipated that site visits will be conducted regularly by a trained technician in order to collect monitoring data and perform preventative maintenance. The following contacts are provided as references:

Role Contact Name Firm Office Number Cell Number

Facility Operator Mike Merryfield Art Brass Plating 206-767-4443 Property Owner Dean Allstrom Dean Allstrom 206-767-4443 Project Manager Doug Hillman Aspect Consulting 206-838-5833 206-399-0318 Remediation Engineer

Jeremy Porter Aspect Consulting 206-838-5835 206-790-2129

Field Engineer Eric Marhofer Aspect Consulting 206-838-6582 206-778-7022

Emergency Services Seattle Fire Department

Seattle Fire Department

911

Regulatory Site Mgr Ed Jones Dept of Ecology 425-649-4449 Construction Contractor

Jay Wilcox Clearcreek Contractors

425-252-5800

GAC Contractor Alex Peru Siemens 360-699-7392

Waste Disposal Contractor

Jennifer Goltz Philip Services Corporation

206-200-5677

System Maintenance H2 Oil Recovery Equipment

541-382-7070

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2 Remediation System Description A layout of the SVE/AS system is presented on Figures 1 and 2. The process and instrumentation diagram (P&ID) for the system is presented in Figure 3. The following sections provide a brief overview of each system’s processes and equipment.

The SVE/AS equipment skid was constructed by H2 Oil Recovery Equipment in Bend, Oregon. The SVE/AS system manual provided with the equipment is included as Appendix A to this Plan and contains a description of system components and manufacturer specifications.

2.1 Soil Vapor Extraction System SVE is an in situ soil treatment involving the application of vacuum to a series of wells screened above the groundwater table, in the vadose zone of the subsurface, to remove air from the soil pore space. Along with the air, VOCs such as TCE are extracted. The off-gas stream is collected and treated using a granular activated carbon (GAC) adsorption to remove VOCs. The SVE system at ABP includes the following components:

Ten horizontal SVE trenches;

Twelve SVE wells;

Two sub-slab SVE sumps;

A vacuum blower;

A moisture separator/particulate filter;

A moisture separator pump;

A condensate storage tank; and

Two GAC units.

2.2 Air Sparge System AS is an in situ groundwater treatment involving the injection of air into a series of wells screened below the groundwater table, in the saturated zone of the subsurface, to volatilize VOCs in the groundwater. The liberated VOC vapors are extracted by the SVE system. The AS system at ABP includes the following components:

Twenty-eight AS wells;

An air compressor; and

A heat exchanger.

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2.3 Soil Vapor Extraction/Air Sparge Interaction One of the primary design criteria for the SVE/AS system is a high ratio of SVE to AS flow in order to prevent the migration of vapors through the subsurface and maximize capture by the SVE system. Generally, the SVE/AS system is designed to extract soil vapor at a rate of 10 times the sparging rate, which provides a high factor of safety to minimize risks of indoor air quality impacts and soil vapor migration (USACE, 1997).

At ABP, air is injected into each AS well at flow rates up to 5 cubic feet per minute (cfm) and soil vapors are extracted at a combined flow rate of approximately 400 cfm. Based on these flow rates, the AS system is operated as four separate zones, each containing seven AS wells. The SVE system operates continuously, while the AS system cycles through the four separate banks of AS wells so that only one zone is on at any given time. This allows for higher air injection flows at individual AS wells, and consequently more effective groundwater remediation, while maintaining a high ratio of total SVE flow to total AS flow.

2.4 220 Findlay Vapor Mitigation System During the system startup and optimization period described in the Construction and Startup Report (Aspect Consulting, 2008a), it was noted that operation of AS wells adjacent to the 220 Findlay property resulted in slightly elevated pressure beneath the building slab. Initially, the SVE system was extended around the perimeter of the building in an attempt to provide greater influence below the building and prevent the potential for vapor intrusion. Ultimately, the existing SVE system was not able to sufficiently depressurize the area beneath the building, and a sub-slab vapor mitigation system was installed to maintain a consistent negative pressure beneath the building while operating AS wells adjacent to the building. The vapor mitigation system is comprised of two sub-slab sumps tied to a vacuum blower located on the roof of the building. This system must remain in operation as long as the AS wells in the vicinity of the building are in operation. Performance monitoring of this system is included in this O&M Plan and includes confirming operation (see Section 3.1.2) and measuring sub-slab pressure (see Section 3.2). The 220 Findlay vapor mitigation system construction and startup performance testing is provided in Appendix B.

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3 Remediation System Operation Operation of the remediation system primarily deals with performance monitoring of the SVE/AS systems, evaluation of the monitoring data, and making adjustments to increase the effectiveness of the SVE and AS processes described in Section 2. Performance monitoring of the remediation system includes the following elements:

Operational monitoring of SVE/AS parameters;

Soil vapor migration monitoring; and

Groundwater monitoring.

The following sections provide an overview of the SVE/AS system operating procedures, the frequency of performance monitoring is provided in Table 1. Data collected during performance monitoring will be documented on the forms provided in Appendix C or a field notebook, and the results will be transferred to spreadsheets for evaluation. Sampling and chemical analysis will be performed in accordance with the standard methods and procedures summarized in this section and Appendix D.

Basic information and procedures for system operation are provided in the H2 Oil Recovery Equipment SVE/AS system manual in Appendix A, including:

Electrical schematics and programmable logic controller (PLC) programming;

A description of the control panel, switches, and indicator lamps;

A description of system alarms; and

A system startup procedure.

3.1 Operational Monitoring Routine site visits will be made on a monthly basis to monitor the system’s operating parameters, evaluate GAC treatment effectiveness, and identify the need for adjustments to SVE and AS flow rates. The tools/materials typically needed to conduct operational monitoring and sampling include:

A key to the roof of ABP;

A remediation system monitoring field sheet (Appendix C);

A hot-wire anemometer to measure air velocity;

Gastec sampling pump and detection tubes to measure TCE concentrations;

1-Liter SUMMA® canisters to collect influent and effluent vapor samples for laboratory analysis of VOCs; and

Hearing protection.

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3.1.1 Monitoring Parameters The following operating parameters will be measured and recorded during each site visit:

Hours of operation, total vacuum, total flow rate, and exit temperature for the SVE blower;

Individual vacuums, flow rates, and TCE concentrations for each SVE well;

Hours of operation, total pressure, total flow rate, and delivery temperature for the AS compressor;

Individual pressures and flow rates for each AS well;

Amount of condensate collected in the condensate storage tank; and

Influent, middle, and effluent TCE concentrations through the GAC treatment.

In addition to measuring and recording these operational parameters, the system operator will also collect influent and effluent vapor samples from the SVE system using 1-Liter SUMMA® canisters. The SUMMA® samples will be sent to Air Toxics Ltd. in Folsom California for analysis of chlorinated VOCs by EPA Method TO-15. Effluent samples will be collected on a monthly basis, while influent samples will be collected quarterly.

3.1.2 Monitoring Procedures This section is intended to provide an overview of how to collect operational parameters during a typical site visit. In the field, the operator will be comparing the data being collected to previous data to identify general variations in system performance. The evaluation of monitoring data as it relates to operation and adjustment of the system is described in the next section (Section 3.1.3).

Upon arrival to the site, conduct a cursory check to see that the SVE/AS and 220 Findlay vapor mitigation systems are running, this is accomplished with a simple visual observation. A fault due to any one of the system alarms described in the manual provided with the equipment will automatically shut down both the SVE and AS systems;

Note the general condition of above ground piping and equipment by looking for wear and tear on the system components due constant operation of the system and exposure to the elements;

Note the switching of the AS banks by observing that they are cycling according to the programmed interval during the course of the site visit.

Record the hours of operation for the SVE and AS system by holding down the reset button on the front of the control panel and reading the display on the PLC inside;

Record the total vacuum for the SVE system using the gauge located at the SVE blower inlet;

Record the total flow rate for the SVE system using the anemometer to measure air velocity at the port located before the inlet to the GAC units;

Record the exit temperature for the SVE system using the gauge located on the off-gas stack after the SVE blower;

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Record the individual vacuum for each SVE well using the gauges located on the SVE system manifold;

Record the individual flow rate for each SVE well using the anemometer to measure air velocity at the ports located on the SVE system manifold;

Record the individual TCE concentration for each SVE well using the Gastec sampling pump and detection tubes to measure vapor concentrations at the sample ports located on the SVE manifold;

Record the total pressure, total flow rate, and delivery temperature for the AS compressor using the gauges and flow meter located after the compressor outlet;

Record the individual pressures and flow rates for each AS well using the gauges and flow meters on the AS manifold. Manually cycle through the AS banks using the switches located on the front of the control panel to collect readings for the AS banks not currently in operation. Allow 5 minutes for each AS bank to stabilize before taking readings;

Record the amount of condensate collected in the condensate storage tank;

Record the influent and middle TCE concentrations through the GAC treatment system using the Gastec sampling pump and detection tubes to measure vapor concentrations at corresponding sample ports located before and in between the GAC units;

Collect a vapor sample of the GAC treatment system effluent at the sample port located on the off-gas stack after the SVE blower using a 1-Liter SUMMA® canister. Send the sample to the laboratory as soon as possible after collection; and

On a quarterly basis, collect a vapor sample of the GAC treatment system influent at the sample port located before the GAC units using a 1-Liter SUMMA® canister. Send the sample to the laboratory as soon as possible after collection.

3.1.3 Evaluation of Operational Monitoring Data A general discussion of monthly operational monitoring data as it relates to system performance is provided below. Evaluation and adjustment of system operations as a result of operational monitoring will be reported as part of the progress reports to Ecology described in Section 5.

SVE Hours of Operation The SVE system will operate continuously, as long as the remediation system is in operation. The objective of the SVE system is two-fold:

1. To maximize mass removal of VOCs from the subsurface through extraction and treatment using GAC; and

2. To prevent vapor migration and intrusion into surrounding commercial and residential structures.

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SVE Flow Rate, Vacuum, and Temperature Individual SVE vacuums are generally maintained at approximately 5 inches of water column (in wc) for horizontal trenches and 10 in wc for vertical wells. The total vacuum at the SVE blower is generally maintained at approximately 65 in wc. Flow rates are related to vacuums, and are monitored for variation, but there are no specific target flow rates for the SVE system. Temperature generally ranges between 35 and 55 degrees Celsius depending on the season, if temperatures are observed outside this range then the system will be evaluated to determine the cause.

A steady increase in SVE flow rates and/or decrease in vacuums over the course of three or more monthly visits indicates potential short-circuiting of the SVE system. Short-circuiting will be evaluated by inspecting well monuments, cracks in asphalt or concrete, and utility penetrations while SVE is running. Short-circuiting will be evaluated with a smoke pencil and by listening for air flow in suspected short-circuiting areas. Short-circuiting in well casings will be corrected by hydrating well seals, and utility penetrations or cracks will be sealed if contributing significantly to air leakage.

A steady decrease in SVE flow rates and/or increase in vacuums over the course of three or more monthly visits indicates potential blockage in pipelines, most likely due to condensation; refer to Section 4.2.2 for maintenance procedures.

AS Hours of Operation In general, the AS system will operate continuously with the exception of scheduled shutdowns for site wide water level measurement, quarterly groundwater monitoring events, and preventative maintenance. The objective of the AS system is to maximize mass removal of VOCs from groundwater through sparging with compressed air.

AS Flow Rate, Pressure, and Temperature Individual AS well flow rates are generally maintained between 1 and 3 cfm and pressures generally range from 8 to 15 psi. Flow rates will be maximized to the extent possible given the constraints of balancing SVE and AS flows (see below) and results of soil vapor migration monitoring (see Section 3.2). The total pressure for the AS compressor will be maintained between 12 and 15 pounds per square inch (psi) to minimize load and wear on the compressor motor and vanes. Temperature generally ranges between 10 and 30 degrees Celsius depending on the season, if temperatures are observed outside this range then the system will be evaluated to determine the cause.

A steady decrease in pressure and/or increase in flow at an air sparge well over the course of three or more monthly visits indicates preferential channels have formed, suggesting frequency of injection or flow rate should be reduced. The air sparging on-off durations will be optimized based on short-term pressure and flow rate measurements. Increasing pressure indicates a ‘developing’ sparge area; decreasing pressure indicates a ‘collapsing’ sparge area (channelization begins). The goal will be to cycle to the next bank before the sparge area collapses.

A steady increase in pressure and/or decrease in flow at an air sparging well over the course of three or more monthly visits indicates potential fouling/plugging and the need to redevelop the well. Refer to Section 4.2.1 for maintenance procedures.

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SVE/AS Balance To maintain balance, and reduce the potential for vapor intrusion at surrounding commercial and residential structures, flow rates from individual extraction points will be controlled using valves for each well located on the SVE manifold. Cumulative air flow for the SVE and AS system will be calculated for four discrete areas as follows:

Zone Red consists of wells and extraction points underneath the ABP building footprint;

Zone Yellow consists of wells and extraction points at the southern perimeter of the ABP building;

Zone Blue consists of wells and extraction points at the western and northwestern perimeter of the ABP building; and

Zone Green consists of wells and extraction points at the perimeter of the 220 Findlay building.

The design guidelines for AS flow rates in the Red, Yellow, and Blue Zones are to not exceed 33 percent the SVE flow rate to ensure capture of sparging vapors. The design guideline for AS flow rate for wells (AS-20, AS-21, AS-23, and AS-25) in the Green Zone is to not exceed 10 percent of the SVE trench flow rate (SVE-G). Flow rates at AS and SVE wells will be adjusted as necessary to balance system flows.

TCE Mass Removal If individual SVE locations have no measurable VOC concentration, then flow from those points will be reduced and the capacity used to increase flow from points with measurable VOCs, provided that vacuum is maintained at vapor migration monitoring points in the vicinity of those SVE points being reduced (see section 3.2 for Soil Vapor Migration Monitoring procedures). Overall mass removal of TCE by the SVE system will be measured using total hours of operation and measured influent concentrations to the GAC treatment system.

SVE Condensate Based on field observations, condensate does not accumulate at a significant rate in the storage tank; however, the tank is equipped with a high level float switch that will shut the system down when the tank is nearing capacity. Therefore, the tank will be maintained in accordance with the Section 4.2.8 to ensure continuous operation of the system.

GAC Treatment Effectiveness The GAC treatment system consists of two 2,000-pound GAC units operating in series: the first unit referred to as the lead unit and the second unit referred to as the lag unit. The effectiveness of the GAC treatment system is based on the removal of TCE from the vapor stream as follows:

High Concentration Condition (GAC influent greater than 15 ppmv TCE). The lead GAC will be replaced when TCE concentrations exiting the lead GAC unit exceed 10 percent of the inlet concentration; or

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Low Concentration Condition (GAC influent less than 15 ppmv TCE). The lead GAC will be replaced when TCE concentrations exiting the lag (second) unit exceed 0.15 ppmv.

These criteria together were selected to provide an average concentration of TCE emitted from the stack of no more than 0.15 ppmv, which is predicted to result in an average concentration at ground level of no more than 0.2 µg/m3, during the operational lifetime of the system. 0.2 µg/m3 is equivalent to a cancer cumulative exceedence factor (CCEF) of 10. The rational, calculations, and modeling for this criteria is discussed in detail in Appendix A of the Design Plans and Specifications, and Construction and Performance Monitoring Plan for the Art Brass Plating Interim Action (Aspect Consulting, 2008c). If laboratory analysis of samples of the treatment system effluent collected with SUMMA canisters (see Section 3.1.2) indicates other chlorinated constituents are present, the allowable discharge will be based on a maximum allowable CCEF of 10 (see the Vapor Intrusion Assessment Work Plan for details of this calculation). Additionally, during the evaluation of system performance, if maximum concentrations exceed a CCEF of 10, average discharge concentrations will be calculated to determine if the above thresholds are appropriate. If at any time the average concentration exceeds a CCEF of 10, the change out criteria will be modified as needed to achieve this standard.

To use the GAC units to their fullest potential, once the lead GAC unit is replaced, the former lag unit will become the new lead unit as described in section 4.2.9.

3.1.4 Contingency Actions based on Operational Monitoring The table below is a summary list of actions to be taken based on conditions observed during system monitoring.

Condition Action

Condensate collection tank >75% full Arrange for condensate disposal

GAC unit(s) exceed allowable discharge limit (see Section 3.1.2)

Arrange for GAC change out

AS flow > 33% SVE flow for Red, Yellow, or Blue zones

Reduce AS flow or increase SVE flow within affected zone to meet criteria

AS flow > 10% SVE flow for Green zone Reduce AS flow or increase SVE flow within affected zone to meet criteria

Condensate collected within SVE line Attempt to flush by maximizing flow

Attempt to drain by reducing flow

Locate collected condensate and attempt to remove

Reduce AS within affected zone

Water collected within AS flow meter Open bleed valve to flush water from flow meter

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3.2 Soil Vapor Migration Monitoring In addition to AS/SVE balancing (described above), soil vapor migration monitoring will be performed at 17 permanent vapor monitoring points on a monthly basis to verify there is no potential for vapor intrusion at nearby commercial and residential buildings. The tools/materials typically needed to conduct soil vapor migration monitoring include:

The vapor migration monitoring field sheets (Appendix C) or a field notebook;

The SOP for soil vapor monitoring (Appendix D);

A digital micro-manometer to measure vapor pressure;

Gastec sampling pump and detection tubes to measure TCE concentrations in soil vapor;

An air sampling pump for purging vapor monitoring points prior to sampling;

High visibility traffic vest and cones; and

Hand tools for accessing monitoring point monuments.

3.2.1 Soil Vapor Monitoring Parameters Figure 2 shows the permanent soil vapor migration monitoring locations that will be monitored for pressure and VOC concentration, including:

Nine vapor monitoring probes (VP-1 through VP-9);

Two cross-slab pressure monitoring point (220F-SS1 and -SS2); and

Six shallow monitoring wells (MW-6, MW-8, MW-9 and MW-12 through MW-14) completed across the water table.

Soil vapor VOC sampling was conducted at all points in December 2008 to establish baseline soil vapor concentrations. The sampling was conducted using an air sampling pump and quantitative detection tubes for TCE. The detection tubes have a detection limit of 125 parts per billion by volume (ppbv). If TCE was not detected at a monitoring point using quantitative detection tubes, a sample was collected using a 1-Liter SUMMA canister and analyzed for TCE by EPA Method TO-15 with a maximum detection limit of 10 ppbv.

3.2.2 Evaluation of Soil Vapor Monitoring Data Pressure and TCE concentrations in soil gas at extraction points, vapor points, and monitoring wells will be measured to document where air is flowing and to help identify what areas are being remediated. Negative pressures and declining TCE concentrations will indicate remedial progress. Positive pressures will indicate lack of capture by the SVE system, and will trigger changes in system operation if detected in shallow soils beneath or near structures.

Positive pressure at a monitoring location will trigger measurement of TCE concentrations in soil vapor at that location. If positive pressure is routinely observed at a

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monitoring location, then there is likely a lack of capture by SVE system in that area. If positive pressures are accompanied by increased TCE concentrations from baseline measurements, then modification to the system will be necessary either through adjustment of AS and SVE flow rates or the expansion of the SVE system.

Soil vapor monitoring locations used to evaluate effectiveness at preventing vapor intrusion include all vapor point and shallow monitoring wells around the perimeter of the 5516 3rd Avenue South (Art Brass facility) and the 220 South Findlay Street buildings. The monitoring points used to evaluate specific buildings, and the assessment protocol to be followed, is described in the Vapor Intrusion Assessment Work Plan (Aspect Consulting, 2008d).

3.2.3 Contingency Actions based on Soil Vapor Monitoring Pressures below the slabs in the ABP facility and the 220 Findlay facility should be maintained lower than pressures above the slabs, and soil gas pressures approaching surrounding facilities laterally should remain higher than pressures more distal from these facilities. No significant increase in soil vapor TCE concentrations (defined as twice the baseline TCE concentration) should be observed at monitoring points near surrounding facilities.

If these conditions are not met, then AS flow rates adjacent to the affected area will be reduced and/or SVE flow rates will be increased until pressures and/or TCE concentrations decline to below baseline.

If the situation cannot be corrected by adjusting flow from/to existing points, one of two contingency actions will be conducted, depending on a cost-benefit analysis:

The AS system in the affected area would be temporarily shut down while additional SVE wells or trenches are installed; or

Obtain access to potentially affected properties and evaluate if indoor air conditions require corrective action. The first step in such an evaluation will be to measure the cross-slab pressure differential at the building in question; if a positive pressure is observed, an indoor air assessment will be conducted. If the indoor air quality indicates negative impacts due to intrusion of vapors, and the problem cannot be remedied by expansion of the SVE system, then a vapor mitigation system will be installed.

3.3 Groundwater Monitoring and Sampling Groundwater monitoring will be performed at 19 wells to evaluate remediation system performance. The AS system will be temporarily turned off approximately 1 week before groundwater sampling to allow water levels to stabilize and provide representative groundwater conditions. Depending on a well’s proximity to the air sparging network and subsurface geology, the air injected by the system can result in localized, sporadic fluctuations in the water table. In our professional experience, one week has been a sufficient amount of time for the water levels and groundwater conditions to stabilize.

Water levels will not be collected while the AS system is on because the sporadic fluctuations in the water table (bubbling of water in monitoring wells) makes collection

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of accurate water levels impractical. Also, operation of the system is not expected to have a significant effect on hydraulic gradients outside the treatment area at this site.

The schedule of groundwater monitoring will be conducted according to the most current groundwater monitoring plan available under the Agreed Order between Art Brass Plating and Ecology. Standard field procedures and a Quality Assurance Project Plan (QAPP) were developed under the scope of work for the RI Work Plan, and are adopted for this work. The standard operating procedures for groundwater sampling are provided in Appendix D.

3.3.1 Groundwater Monitoring Locations Figure 1 illustrates the locations of the groundwater monitoring wells, including:

Six wells on property or immediately downgradient of the facility (existing wells MW-1 through MW-5 and PMW-1) to monitor the effectiveness of source area remediation;

Eight existing and proposed wells downgradient of the ABP facility (MW-7 through MW-11, and MW-13 through MW-15) screened across the water table to monitor changes in shallow groundwater conditions near other facilities;

Two off-property wells (MW-8-30 and MW-11-30) to monitor the TCE plume in groundwater at depths below the water table interval. Wells MW-8-30 and MW-11-30 are screened approximately 20 to 30 feet deep. These depth intervals correspond to the intervals below the water table of highest concentrations based on previous investigations; and

Three upgradient wells, including wells MW-6 and MW-12 screened across the water table, and well MW-6-30 screened approximately 20 to 30 feet deep. These wells will be used to provide a measure of background water quality to evaluate remediation performance.

Data collected from additional wells monitored as part of the RI will be reviewed as appropriate.

3.3.2 Groundwater Monitoring Methods and Parameters Groundwater levels will be measured at all wells using a water level indicator, to estimate groundwater flow direction and vertical and horizontal gradients. Groundwater samples for this interim action will be collected using low-flow sampling techniques consistent with procedures outlined in the RI Work Plan. Field parameters measured during sampling will include temperature, pH, electrical conductivity, dissolved oxygen and oxidation-reduction potential (Eh). Groundwater sampling activities will be recorded on the appropriate field sheet (Appendix C).

All groundwater samples will be submitted for analysis of chlorinated VOCs. Samples will be submitted to Analytical Resources of Tukwila, Washington, for analysis. Analytical methods are provided in Table 2.

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3.3.3 Evaluation of Groundwater Monitoring Data Groundwater monitoring parameters will be used as follows:

Dissolved oxygen data will be used to evaluate area of influence of air sparging wells;

Eh data will be used to evaluate the effect of air sparging on redox conditions, and the potential effect on redox-sensitive constituents (such as dissolved metals) and natural biodegradation of contaminants; and

VOC data will be used to indirectly measure how well injected air is distributed (rather than direct measurement of air saturation). High reductions in VOCs will indicate treatment is well distributed across contaminated area.

When it is determined that VOC concentrations in groundwater have reached an asymptotic state, temporary shutdown of the AS system will be implemented to evaluate potential for rebound, or to what degree residual contamination is desorbing from soil. High rebound suggests that remediation has become rate-limited by the rate of desorption/diffusion of VOC from soil. Under such a condition, pulsed operation of the AS system will be considered.

The tentative plan for rebound testing will consist of turning off the AS system for 3 months following quarterly groundwater monitoring, until the completion of a subsequent round of quarterly groundwater monitoring. If no appreciable increases in groundwater concentrations are observed after 3 months, then the AS system will remain off for an additional 3 months and another round of groundwater monitoring. When/if appreciable increases in groundwater concentrations are observed, the AS system will be restarted and operated for 3 months. AS and SVE parameters will be monitored one week after restarting the system, to evaluate short-term changes in operating conditions and adjust/balance flows as necessary, and then monthly. This process will be repeated as necessary to maximize the effectiveness of the remediation system and may be modified based on operational data, observations, and discussions with Ecology.

3.3.4 Contingency Actions based on Groundwater Monitoring If an increasing trend in groundwater concentrations over two consecutive quarters is observed at any monitoring wells located near other facilities, and the maximum concentration is more than two times the baseline concentration, TCE concentrations in soil gas will be measured at the well and adjacent vapor monitoring point. If an increase is observed, the protocol described above for addressing an increase in soil vapor concentrations will be followed. Wells that will be used to evaluate each neighboring building are described in the Vapor Assessment Work Plan (Aspect Consulting, 2008d).

If groundwater monitoring indicates a change in groundwater redox conditions that could oxidize naturally occurring metals such as chromium into a more mobile form, additional metals analysis will be considered for the groundwater monitoring program. Analysis of any observed changes in redox conditions relative to pH/Eh stability diagrams will be included in the semi-annual performance evaluation progress report (see Section 5).

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PROJECT NO. 050067-006 MAY 21, 2010 15

4 Remediation System Maintenance The SVE/AS system contains specialized and complex process equipment. Routine maintenance conducted on a monthly basis in conjunction with performance monitoring is required to ensure that process equipment continues to operate properly. Disabled or improperly working equipment will reduce treatment efficiency of the system. Repair costs for poorly maintained equipment usually exceed the cost of regular preventative maintenance and may increase the downtime of the remediation system.

4.1 Housekeeping The SVE/AS system is location on ABP property and it is important to keep the site clean and in good repair. Housekeeping will cover the equipment area located on the roof of the building, the fenced equipment enclosure at ground level, and the areas near SVE wells and piping. Poor housekeeping creates safety and health hazards and can mask or create process and mechanical problems.

4.2 Equipment Maintenance During routine monthly site visits equipment will be inspected and routine housekeeping will be performed. The following sections detail recommended maintenance for the various system components, if it is determined they require it, following inspection. Component literature is contained in the system manual provided by H2 Oil Recovery Equipment in Appendix A.

4.2.1 Air Sparge Wells The screens of the AS wells will require redevelopment if they become plugged. Access to the AS wells is limited because they were paved over when the system was installed to minimize the potential for short-circuiting of injected air to the surface. If the system operator notices a reduction or blockage of air flow to an AS well, plugging may be a factor. Several types of plugging are possible, including:

Precipitation of calcium carbonate (calcite) due to solubility changes as the pH increases;

Precipitation of iron and magnesium due to oxidation of dissolved inorganic species in the stripping well; or

Growth of iron bacteria or other slime within the well casing.

The specific cause of plugging must be ascertained to develop an appropriate control or redevelopment approach. Because the AS wells are not easily accessible, and impacts to system performance due to plugging may vary, the cost-benefit of redevelopment will be considered before further action is taken.

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16 PROJECT NO. 050067-006 MAY 21, 2010 (REVISED SEPTEMBER 15, 2010)

4.2.2 Soil Vapor Extraction Piping SVE piping was installed to minimize the entrainment of water in the lines; however, if the system is experiencing a drop in flow from a well, or an increase in vacuum to maintain air flow, it will be necessary to clear the lines of condensate because water has accumulated to the point that it is affecting system performance.

Water entrainment is primarily a seasonal condition becoming more of a problem in winter when warmer air being extracted from below ground contacts colder piping above ground, causing condensation to form inside the piping. It can also be aggravated by a higher water table and air sparging action causing bubbling within SVE wells. If left untreated water entrainment can result in decreased performance or even complete blockage of portions of the SVE system. If 1) the system operator notices steadily decreasing flows or increasing vacuums for a given SVE well or trench over the course of three or more monthly performance monitoring visits; 2) a complete loss of flow is noted during a single visit; or 3) SVE flow from a well or trench has reduced such that the AS/SVE balance requirements are not being met (see Section 3.1.3) then the following actions will be performed to restore SVE performance:

Tag the valves on SVE lines and AS wells associated with the zone of the SVE system that shows reduced performance.

Temporarily shut down the AS wells in the affected zone closing the valves. Allow time for pressures at the AS wells to stabilize.

Temporarily shut down the affected SVE lines closing the valves. Allow time for entrained water to gravity drain back to the SVE wells, sumps, or trenches.

Restart the affected SVE lines by opening the valves and monitoring SVE performance for 10 minutes.

If the problem persists after 10 minutes, it is likely that water is entrained within a portion of the SVE line where it cannot gravity drain. In this case, the SVE line will require modification to remove entrained water (e.g. installing a drainage port at low point in the pipe or an access point to allow tubing from a peristaltic pump to reach the blockage). Water drained from the SVE system will be collected and transferred to the condensate storage tank.

If the problem does not recur after 10 minutes, continue to evaluate the performance of the SVE system during monthly performance monitoring.

4.2.3 Soil Vapor Extraction Blower The DR 909 Rotor® regenerative SVE blower is equipped with sealed bearings and does not require regular maintenance or lubrication. The blower will be visually inspected on a monthly basis for the accumulation of dirt, oil, grime, etc. Accumulation of these substances on surfaces can inhibit heat dissipation from the equipment, which can cause damage through overheating. The surfaces of the blower will be wiped down when accumulation of dirt/grime is apparent.

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PROJECT NO. 050067-006 MAY 21, 2010 17

4.2.4 Moisture Separator The moisture separator (MS) and internal filter sock will be visually inspected on a monthly basis. If the MS contains water, it will be drained. The filter sock will be replaced if it shows signs of plugging. If the vacuum gauge between the SVE blower and the MS indicates an increase of greater than 5 in wc from normal operating pressure, then the filter sock is becoming plugged.

4.2.5 Moisture Separator Pump The MS pump will be visually inspected on a monthly basis for the accumulation of dirt, oil, grime, etc. Accumulation of these substances on surfaces can inhibit heat dissipation from the equipment, which can cause damage through overheating. The surfaces of the pump will be wiped down when accumulation of dirt/grime is apparent. This is a closed coupled unit and ball bearings are located inside the motor, they are permanently lubricated, no greasing is required.

4.2.6 Air Sparge Compressor The Rietschle Thomas DTA 80 rotary vane AS compressor will be visually inspected on a monthly basis for the accumulation of dirt, oil, grime, etc. Accumulation of these substances on surfaces can inhibit heat dissipation from the equipment, which can cause damage through overheating. The surfaces of the compressor will be wiped down when accumulation of dirt/grime is apparent. Additional maintenance needs for internal parts of the compressor include:

Lubrication of the bearings on an annual basis;

Visual inspection of the carbon vanes for wear at 6 months intervals. Based on past experience vanes require replacement after approximately 8 months of operation; and

Visual inspection and replacement as necessary of the inlet filter at 6 month intervals.

4.2.7 Heat Exchanger and Ventilation Fans The heat exchanger and ventilation fans in the SVE blower and the AS compressor sound enclosures will be visually inspected on a monthly basis for the accumulation of dust and grime on the fan guards, propellers, and motors. Accumulation of these substances on surfaces can inhibit heat dissipation from the equipment, which can cause damage through overheating. The surfaces of the fans will be wiped down when accumulation of dirt/grime is apparent. The motor bearings will be lubricated every six months using Society of Automotive Engineers (SAE) 20 oil.

4.2.8 Condensate Storage Tank The condensate storage tank will be visually inspected on a monthly basis for accumulation of water. Based on field observations of the system during the first year of operation, condensate does not accumulate at a significant rate in the condensate storage tank. Accumulation of condensate in the storage tank, if it occurs at all, will likely be generated during manual draining of SVE lines using drainage ports installed at low

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18 PROJECT NO. 050067-006 MAY 21, 2010 (REVISED SEPTEMBER 15, 2010)

points in the piping, or a peristaltic pump to access low points in piping where drainage port installation is not feasible due to spatial constraints. The amount of condensate generated during draining of SVE lines will vary seasonally, but is not expected to be more than a few gallons per month. Due to the likely presence of F002-listed solvents, condensate will be handled and disposed of as a dangerous waste. In accordance with applicable dangerous waste regulations for small quantity generators, disposal of condensate will be arranged when the 200 gallon (under 2200 pounds) condensate tank is nearing capacity. Condensate removal, transport, and disposal will be performed by the Waste Disposal Contractor.

4.2.9 Granular Activated Carbon Units The influent and effluent stream through the GAC units will be sampled on a monthly basis for breakthrough according to the operating procedures described in Section 3.1.3. Once it has been determined that breakthrough has occurred, the GAC Contractor will be contacted regarding change out and disposal of the spent GAC. The spent GAC will be regenerated or disposed of as a dangerous waste. After the lead GAC unit has been changed out, the lag unit will become the new lead and the GAC units will be reconnected to the system in series.

4.3 Ecology Notification It is anticipated that the remediation system will need to be shut down from time to time to accommodate the routine equipment maintenance activities described in the preceding sections. Shutdown of the air sparging components of the remediation system may occur for up to a week for monitoring or maintenance activities such as 1) replacement of the carbon vanes (approximately every 8 months: see Section 4.2.6); and 2) in advance of groundwater monitoring or water level monitoring events. Routine shut downs will be reported as part of the progress reports to Ecology described in Section 5.

Ecology will be notified immediately (or in advance if possible):

If the air sparging system is shut down for more than one week;

If the SVE system will be off for more than a few hours (e.g., for unscheduled maintenance or carbon change out);

If positive pressure beneath the 220 Findlay building is observed; or

If the 220 Findlay vapor mitigation system will be off for any period.

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PROJECT NO. 050067-006 MAY 21, 2010 19

5 Reporting A report on the status of the interim action (i.e., remediation system) will be included in progress reports, which are submitted quarterly to Ecology. As per the Agreed Order, the status report will include the following for the designated reporting period:

Description of the work performed;

Environmental results attributed to the measures;

Problems associated with O&M, and corrective actions taken, or proposed to be taken, to resolve the problem(s); and

Interim measures work planned in the next reporting period.

On a semi-annual basis, the progress report will include the following information:

Interim measure performance data;

Comparison of the effectiveness of each measure compared to its design goals, effectiveness at startup, and its effectiveness since the last reporting interval;

If performance monitoring data do not meet system objectives for remediation progress, recommendations to improve system effectiveness; and

If applicable, a discussion of efforts on-going to ensure that the measure does not transfer contamination to another medium, and an estimate of risks associated with cross-media contaminant transfer if occurring.

If data indicate that the system is not making adequate progress toward achieving system objectives, a separate report describing planned assessment and/or corrective actions to remedy the problem would be prepared.

6 Revisions to the O&M Plan If revisions to the O&M plan are necessary as the project proceeds, amendments to the plan will be subject to review and approval by Ecology prior to finalization.

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20 PROJECT NO. 050067-006 MAY 21, 2010 (REVISED SEPTEMBER 15, 2010)

References Aspect Consulting, 2007, Draft Interim Cleanup Action Plan, Art Brass Plating, Seattle,

Washington.

Aspect Consulting, 2008a, Construction and Startup Report, Art Brass Plating, November 21, 2008, Seattle, Washington.

Aspect Consulting, 2008b, Project Specific Health and Safety Plan, Art Brass Plating, March 9, 2008, Seattle, Washington

Aspect Consulting, 2008c, Design Plans and Specifications, and Construction and Performance Monitoring Plan, Art Brass Plating, April 1, 2008, Seattle, Washington.

Aspect Consulting, 2008d, Vapor Intrusion Assessment Work Plan, Art Brass Plating, Aspect Consulting, August 29, 2008, Seattle, Washington.

Aspect Consulting, 2008, Remedial Investigation Work Plan, Art Brass Plating, Aspect Consulting, September 25, 2008, Seattle, Washington.

New York State Department of Health, Guidance for Evaluating Soil Vapor Intrusion in the State of New York, October 2006.

Limitations Work for this project was performed and this report prepared in accordance with generally accepted professional practices for the nature and conditions of work completed in the same or similar localities, at the time the work was performed. It is intended for the exclusive use of Art Brass Plating for specific application to the referenced property. This report does not represent a legal opinion. No other warranty, expressed or implied, is made.

Table 1: System Operation and Performance Monitoring SchedulesArt Brass Plating Interim ActionSeattle, Washington

System Operation ScheduleSVE systemAS systemPerformance Monitoring ScheduleOperational Monitoring Vapor Migration MonitoringGroundwater - Water LevelsGroundwater - Field Parameters, CVOCsNotes:

M indicates monthly eventQ indicates quarterly event

● Operational monitoring will include collecting remediation system parameters and GAC vapor monitoring (see Remediation System Monitoring Field Sheet in Appendix C).● Vapor Migration Monitoring - Pressure will be measured using a micromanometer (see Vapor Migration Monitoring Field Sheets in Appendix C).

M

QQQ

QQQQ

Q

MMMM

M M M M

December

M

January February

M M

March April

MMM MM

M MM

MM M M

NovemberMay June August SeptemberJuly October

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Table 1Page 1 of 1

Table 2: Soil Vapor and Groundwater Monitoring Locations and AnalysesArt Brass Plating Interim ActionSeattle, Washington

PressureTCE

Concentration 2Field

Parameters3Chlorinated

VOCs4

VP-1 X XVP-2 X XVP-3 X XVP-4 X XVP-5 X XVP-6 X XVP-7 X XVP-8 X XVP-9 X X220F-SS11 X X220F-SS21 X XMW-1 X XMW-2 X XMW-3 X XMW-4 X XMW-5 X XMW-6 X X X XMW-6-30 X XMW-7 X XMW-8 X X X XMW-8-30 X XMW-9 X X X XMW-10 X XMW-11 X XMW-11-30 X XMW-12 X X X XMW-13 X X X XMW-14 X X X XMW-15 X XPMW-1 X X

Notes:1) 220 Findlay - cross-slab pressure monitoring points2) At monitoring points exhibiting positive pressure, soil vapor sampling will be conducted with low-level TCE detector tubes (125 ppb detection limit).

If detector tube result is non-detect, and baseline TCE concentration at the monitoring point was below the detection limit of the detector tubes, then sampling will be conducted with a SUMMA canister and analyzed for VOCs using TO-15.

3) Groundwater field parameters include water level, temperature, pH, electrical conductivity, dissolved oxygen, and oxidation-reduction potential (Eh).4) Chlorinated VOCs will be analyzed by EPA Method 8260B. Wells that expect to have low-level VOC concentrations (MW-6, MW-6-30, and MW-10 through MW-14) will be analyzed by a modified 8260B method with a 10mL purge and have a reporting limit of 0.2 ppb.

Well ID Groundwater MonitoringVapor Migration Monitoring

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Table 2Page 1 of 1

APPENDIX A

SVE/AS System Manual (H2 Oil Recovery Equipment)

APPENDIX B

Vapor Mitigation System Construction and Startup Report 220 South Findlay Street

VAPOR MITIGATION SYSTEM  CONSTRUCTION AND STARTUP REPORT 220 South Findlay Street Prepared for: Art Brass Plating Inc. 

Project No. 050067‐006   September 15, 2010

e a r t h + w a t e r Aspect Consulting, LLC 401 2nd Avenue S. Suite 201 Seattle, WA 98104 206.328.7443 www.aspectconsulting.com

ASPECT CONSULTING

PROJECT NO. 050067-006 SEPTEMBER 15, 2010 1

Contents

Introduction ......................................................................................................... 2 

System Installation ............................................................................................. 2 

Verification of Sub-Slab Depressurization ....................................................... 3 

System Startup and Monitoring ......................................................................... 3 

References .......................................................................................................... 4 

Limitations ........................................................................................................... 4 

 

List of Figures 1 Vapor Mitigation System Layout

2 Vapor Mitigation System Cross-Section

List of Appendices

A Fan Specifications

B IM Installation Report Form

C System Installation Checklist

D Electrical Permit

E Photographs

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2       PROJECT NO. 050067-006 SEPTEMBER 15, 2010

Introduction The building located at 220 South Findlay Street sits just across the street from the Art Brass Plating (ABP) facility and immediately downgradient from the source of volatile organic chemical (VOC) contamination in groundwater beneath the site. ABP is located at 5516 3rd Avenue South, in the Georgetown neighborhood of Seattle, Washington.

Since the discovery of VOCs in the groundwater, ABP has undertaken a number of investigations to identify the extent of the VOC plume, mitigate the plume, and control future migration offsite, including the installation of a combined soil vapor extraction (SVE) and air sparge (AS) system as the interim cleanup action for the site.

During the system startup and optimization of the SVE/AS system, it was noted that operation of AS wells adjacent to the 220 Findlay property resulted in slightly elevated pressure beneath the building slab. Consequently, AS wells in the vicinity of the 220 Findlay building were turned off to prevent impacts to indoor air quality. In order to permit the operation of all the AS wells, and allow the SVE/AS system to reach its full remediation potential, SVE system was initially extended around the perimeter of the building in an attempt to provide greater influence beneath the slab and prevent the potential for vapor intrusion. Ultimately, the SVE system was not able to sufficiently depressurize the area beneath the building, and a sub-slab vapor mitigation system was required to maintain a consistent negative pressure beneath the slab while operating the AS wells adjacent to the building.

System Installation Advanced Radon Technologies Inc. (ART) of Spokane, Washington was selected as the contractor to install the system because of their experience installing similar vapor mitigation systems in the Georgetown neighborhood.

Installation of the vapor mitigation system consisted of coring two 5-inch diameter holes through the slab of the building at the sump locations shown on Figure 1. After removing the soil, a 3-inch diameter perforated polyvinyl chloride (PVC) pipe was placed in the holes and the annular space backfilled with permeable pea gravel. The annular space around the floor penetration was sealed with concrete and a non-perforated pipe was connected to the sump, run up the wall to the ceiling, and through the roof. On the roof the pipe was connected to a fan designed to pull a vacuum underneath the building.

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PROJECT NO. 050067-006 SEPTEMBER 15, 2010 3

ART installed the sub-slab sumps and above ground piping on September 21 and 22, 2009 and performed patented diagnostic testing to confirm a negative pressure field extension beneath the entire slab of the building. The fan for the vapor mitigation system was selected based on the results of the diagnostic testing and ordered by ART. The fan was delivered and installed on October 19 and 20, 2009. Specifications for the fan selected are provided in Appendix A.

Verification of Sub-Slab Depressurization An Aspect Consulting, LLC (Aspect) representative was on site during the diagnostic testing performed by ART to ensure that a negative pressure field extension was achieved beneath the entire slab of the building. The location of the vapor mitigation sumps relative to the differential pressure testing locations are shown on Figure 1. According to the U.S. Environmental Protection Agency, sub-slab depressurization in the range of 0.025-0.035 inches of water column (in wc) is generally sufficient to maintain downward pressure gradients (USEPA, 1993).

Diagnostic testing was performed with the AS system running to ensure that the vapor mitigation system would adequately depressurize the building while the AS system was operating. For the duration of diagnostic testing, all AS wells in the vicinity of the 220 Findlay building were turned on and operated at the maximum flow rates and pressures. Applying vacuum at vapor mitigation sump S-1 resulted in the following pressures at the differential pressure testing locations:

Location Pressure [in wc] VP-1 -0.163 VP-2 -0.200 VP-3 -0.020 VP-4 less than -3 (out of range)

Given these results, it was determined that a second vapor mitigation sump was required near VP-3 in order to maintain sufficient downward pressure gradients beneath the entire building. ART installed sump number two, and subsequent differential pressure testing at VP-3 resulted in pressures of less than -3 in wc (out of range).

System Startup and Monitoring The sub-slab vapor mitigation system at 220 South Findlay Street was started on October 21, 2009. Following startup of the vapor mitigation system, the AS wells in the vicinity of the building were turned on. The vapor mitigation system will remain in operation as long as the AS wells in the vicinity of the building are in operation.

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4       PROJECT NO. 050067-006 SEPTEMBER 15, 2010

Operational monitoring of the vapor mitigation system is included in the Operation and Maintenance Plan for the Art Brass Plating Interim Cleanup Action (Aspect, 2010a) and includes monthly verification of the mitigation system and sub-slab pressures at two permanent sub-slab vapor monitoring points previously installed inside the building (220F-SS1 and 220F-SS2 on Figure 1). Pressure monitoring at these points since startup has demonstrated sub-slab pressures of less than -1.013 in wc. Documentation of pressure monitoring at 220 Findlay points is provided in the quarterly progress reports for the Art Brass Plating interim cleanup action (Aspect, 2010b).

Additionally, mitigation systems require inspection, maintenance, and performance monitoring. Property-specific procedures for inspection, monitoring, and maintenance tasks and frequency will be addressed in future revisions of the Vapor Intrusion Inspection, Monitoring, and Maintenance Work Plan (Aspect, 2008) for Art Brass Plating.

References Aspect, 2008, Vapor Intrusion Inspection, Monitoring, and Maintenance Work Plan, Art

Brass Plating, June 12, 2008, Seattle, Washington.

Aspect, 2010a, Operation and Maintenance Plan, Art Brass Plating Interim Cleanup Action, May 21, 2010, Seattle, Washington.

Aspect, 2010b, Progress Report - January through March 2010, Art Brass Plating Interim Cleanup Action, May 6, 2010, Seattle, Washington.

U.S. Environmental Protection Agency, 1993, Radon Reduction Techniques for Existing Detached Houses, Technical Guidance for Active Soil Depressurization Systems. EPA/625/R-93/011.

Limitations Work for this project was performed and this report prepared in accordance with generally accepted professional practices for the nature and conditions of work completed in the same or similar localities, at the time the work was performed. It is intended for the exclusive use of Art Brass Plating for specific application to the referenced property. This report does not represent a legal opinion. No other warranty, expressed or implied, is made.

APPENDIX A

Fan Specifications

APPENDIX B

IM Installation Report Form

IM Installation Report Form  

 

Address:  220 South Findlay        Date:  September 22, 2009 

Occupant Name:  inStore Technology      Phone:  206‐709‐0125 

Owner’s Name:  Gary Pollastro        Phone:  206‐709‐0125 

Point of Contact:  Gary Pollastro      Phone:  206‐709‐0125 

Contact Information:  Work coordinated through Mr. Pollastro 

Report Completed By:  Eric Marhofer      Company:  Aspect Consulting 

System Installed By:  Dave Gerard      Company:  Advanced Radon Technologies 

Electrician:  Sandor Peterson        Company:  SMP Electrical Services 

 

 A. General Building Information 

Building Age:  Built in 1982 

Building Type:  Commercial 

Building Occupants:  10‐15 employees 

Building Use:  Office building 

Square Footage of Building:  3000 sq ft 

Ceiling Height:  9 ft 

General Description of Building Construction Material:  Primarily Masonry 

Foundation Type:  Slab on grade 

Foundation Materials:  Poured concrete 

   

 

B. Heating and Ventilation Systems 

What types of heating system(s) are used in the building? (check all that apply) 

_X_  Heat pump/furnace (forced air)    ___  Hot air radiation 

___  Steam radiation        ___  Unvented kerosene heater 

___  Wood stove        ___  Electric baseboard 

___  Other, specify:  ___________________________________________________ 

 What types of fuel(s) are used in the building? (check all that apply) 

_X_  Natural gas        ___  Electric 

___  Fuel oil          ___  Wood 

___  Coal          ___  Solar 

___  Other, specify:  ___________________________________________________ 

 What type of mechanical ventilation systems are present and/or currently operating in the building? (check all that apply) 

___  Mechanical fans        _X_  Open windows/doors 

___  Individual air conditioning units    ___  Kitchen range hood 

_X_  Bathroom ventilation fan      ___  Air‐to‐air heat exchanger 

___  Other, specify:  ___________________________________________________ 

 C. Roof Construction 

Is the roof pitched or flat?  Flat 

Is there an attic?  No 

What is the roof comprised of?  Rolled asphalt roofing 

Description of roof support system?  Wooden truss   

 

D. Diagnostic Testing 

Based on the diagnostic testing described in the Vapor Mitigation System Construction and Startup Report, the following minimum vapor pressures have been established to confirm negative pressure extension beneath the building. Pressure testing locations are shown on Figure 1 of the Vapor Mitigation System Construction and Startup Report. Permanent monitoring points were not installed at locations VP‐1,‐2, and ‐3, therefore locations 220F‐SS1 and ‐SS2 will be used to verify system operation during routine monitoring described in the Operation and Maintenance Plan for the Art Brass Plating Interim Cleanup Action. 

Active Soil Depressurization System Specifications Negative Pressure Field Extension in Inches of Water Column [in wc] 

VP‐1  VP‐2  VP‐3  VP‐4 (220F‐SS1)  220F‐SS2 < ‐0.100  < ‐0.200  < ‐0.025  < ‐3  < ‐0.100 

 

APPENDIX C

System Installation Checklist

APPENDIX D

Electrical Permit

APPENDIX E

Photographs

220 South Findlay Street Vapor Mitigation System   

 

 

 

Photo 1 – Floor penetration for sump location S‐1. 

 

 

 

 

 

 

 

220 South Findlay Street Vapor Mitigation System  

 

 

 

 

Photo 2 – Ceiling penetration for sump location S‐1. 

 

 

 

 

 

 

 

220 South Findlay Street Vapor Mitigation System   

 

 

 

Photo 3 – Ceiling penetration for sump location S‐2. 

 

 

 

 

 

 

 

220 South Findlay Street Vapor Mitigation System   

 

 

 

Photo 4 – Floor penetration for sump location S‐2. 

 

 

 

 

 

 

 

220 South Findlay Street Vapor Mitigation System  

 

 

 

 

Photo 5 – Outside of electrical panel. 

 

 

 

 

 

 

 

220 South Findlay Street Vapor Mitigation System  

 

 

 

 

Photo 6 – Inside of electrical panel showing fan switch. 

APPENDIX C

Field Monitoring Forms

Remediation System Monitoring Field Sheet

Soil Vapor Migration Monitoring Field Sheets

Groundwater Sampling Form

Remediation System Monitoring Field SheetArt Brass Plating Interim ActionSeattle, Washington

Date:____________________Staff:____________________

Check box: AS/SVE balance (detailed monitoring on other side)System running(Note alarm and date if shutdown) Cycle 1 Cycle 2 Cycle 3 Cycle 4Visual equipment inspection AS: Field Notes:

SVE:Switching of AS banks AS/SVE:

AS:AS Compressor: SVE:

Hours of operation AS/SVE:Pressure psi AS:

Flow Rate cfm SVE:Temperature oC AS/SVE:

SVE Blower: AS:Hours of operation SVE:

Vacuum Before KO in WC AS/SVE:Blower Inlet Vacuum in WC

Velocity/Flow Rate ft/min cfmExit Temperature oC Notes:

Condensate Level:Storage Tank gal

GAC Treatment:Inlet TCE Conc.: ppmv

Middle TCE Conc.: ppmvStack TCE Conc.: ppmv

Conditions for GAC ChangeoutIF Inlet Conc. > 15 ppmv AND Middle Conc. > 10% Inlet Conc.

IF Inlet Conc. < 15 ppmv AND Stack Conc. > 0.15 ppmv

If storage tank is >75% full, arrange for disposal.

Color indicates Zone (Red, Yellow, Blue, or Green).Measure TCE concentrations with low-level detection tubes.

Subtotal Flows

If flow rate at a vertical SVE well is unsteady or "slurping", reduce vacuum 10%.

If target is not achieved, reduce AS flow rates for the affected Zone by 25%.

SVE flow for individual extraction points will be measured using a hot-wire anemometer.

Initial target maximum AS flow rates are 33% of SVE flows for the Red, Yellow, and Blue Zones; 10% of SVE flows for the Green Zone.

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Remediation System Monitoring Field SheetArt Brass Plating Interim ActionSeattle, Washington

Date:____________________Staff:____________________

TCE Gastech Tube Vacuum Velocity Flow Pressure Flow Pressure Flow Pressure Flow Pressure FlowSVE ID (ppm) (range) (in wc) (ft/min) (scfm) AS ID (psi) (scfm) (psi) (scfm) (psi) (scfm) (psi) (scfm)MW-1 AS-1MW-2 AS-2SVE-1 AS-3SVE-2 AS-4SVE-A AS-5SVE-B AS-6SVE-3A AS-7SVE-3B AS-8SVE-4A AS-27SVE-4B Subtotal: Subtotal: Subtotal: Subtotal:

Subtotal: AS-9AS-10

TCE (range) Vacuum Velocity Flow AS-11MW-4 AS-12SVE-C AS-13SVE-D AS-14SVE-5A Subtotal: Subtotal: Subtotal: Subtotal:SVE-5B AS-15

Subtotal: AS-16AS-17

TCE (range) Vacuum Velocity Flow AS-18MW-3 AS-19MW-5 AS-22SVE-E AS-24SVE-F AS-26

Subtotal: Subtotal: Subtotal: Subtotal: Subtotal:AS-20

TCE (range) Vacuum Velocity Flow AS-21MW-7 AS-23SVE-G AS-25SVE-6/7 AS-28

Subtotal: Subtotal: Subtotal: Subtotal: Subtotal:

SVE Manifold AS ManifoldCycle 4Cycle 3Cycle 1 Cycle 2

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Vapor Migration Monitoring Field SheetArt Brass Plating Interim ActionSeattle, Washington

Pressure/Vacuum (inches water column)

Initials:Event:Date:

Point IDVP-1VP-2VP-3VP-4VP-5VP-6VP-7VP-8VP-9MW-6MW-8MW-9MW-12MW-13MW-14220F-SS1220F-SS2

Field Notes:

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Vapor Migration Monitoring Field SheetArt Brass Plating Interim ActionSeattle, Washington

TCE Concentration (ppm)

Initials: Event: Date:

Point IDPurge Rate

[mL/min]Purge Time

[mm:ss]VP-1 100 01:10VP-2 100 01:10VP-3 100 01:10VP-4 100 01:10VP-5 100 01:10VP-6 100 01:10VP-7 100 01:10VP-8 100 01:10VP-9 100 01:10MW-6 1000 02:05MW-8 3000 4:57MW-9 3000 4:57MW-12 3000 4:57MW-13 3000 4:57MW-14 3000 4:57220F-SS1 100 01:10220F-SS2 100 01:10

Field Notes:

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GROUNDWATER SAMPLING RECORD WELL NUMBER: _______ Page:____ of ____

Project Name: Project Number:

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Date: Starting Water Level (ft TOC):Developed by: Casing Stickup (ft):Measuring Point of Well: Total Depth (ft TOC):Screened Interval (ft. TOC) Casing Diameter (inches):Filter Pack Interval (ft. TOC)

Casing Volume ___________ (ft Water) x ___________ (Lpfv)(gpf) = ___________ (L)(gal) Casing volumes: 2" = 0.16 gpf 4" = 0.65 gpf 6" = 1.47 gpf Sample Intake Depth (ft TOC): 2" = 0.62 Lpf 4" = 2.46 Lpf 6" = 5.56 Lpf

PURGING MEASUREMENTSTime Cumul. Vol. Purge Rate Water Temp. Specific Dissolved pH Eh Turbidity Comments

(gal or L) (gpm or Lpm) Level (ft) (C or F) Conductance Oxygen ORP (NTU)(µS/cm) (mg/L) (mv)

Total Gallons Purged: Total Casing Volumes Removed:

Ending Water Level (ft TOC): Ending Total Depth (ft TOC):

SAMPLE INVENTORYTime Volume Bottle Type Quantity Filtration Preservation Appearance Remarks

Color Turbidity & Sediment

METHODSSampling Equipment and IDs:

Purging Equipment: Decon Equipment:

Disposal of Discharged Water:

Observations/Comments:

V:\050067 Art Brass Plating\O&M Plan\App C_field forms\Groundwater Sampling Form

APPENDIX D

Standard Operating Procedures

Soil Vapor Monitoring

Groundwater Sampling

ASPECT CONSULTING

PROJECT NO. 050067-006-01 APRIL 1, 2008 D-1

Soil Vapor Monitoring SOPs The following Standard Operating Procedures (SOPs) are to be followed when performing soil vapor monitoring for the Art Brass Plating Interim Cleanup Action. The air sparging system will be temporarily shut down during monitoring.

After Soil Vapor Point Installation QA procedures for determining potential for atmospheric leakage during soil vapor sampling for soil vapor monitoring points less than 5 feet deep installed in permeable surfaces or asphalt, and for determining necessary purge volume to obtain a representative sample.

Conduct procedures at least 1 week after vapor point installation.

Connect one end of sampling tubing to sampling port and other end to sampling pump.

Collect ambient readings of O2 and VOC concentration using a multi-gas detector.

Purge well at a rate of 250 mL/min. Monitor off-gas O2 and VOC concentrations using a multi-gas detector. Record results every 30 seconds for at least 5 minutes, or until readings stabilize.

An increase in O2 concentration will indicate possible atmospheric intrusion.

The proper purge volume will be based on when VOC concentrations stabilize (before oxygen readings indicate atmospheric intrusion). If VOC concentrations are not measurable using the multi-gas detector at any wells, the following procedure will be used at vapor monitoring points VP-1 and VP-8 and monitoring well MW-8 to estimate proper purge volume:

Three casing volumes will be purged with the sampling pump.

A TCE detector tube will be used to measure the TCE concentration.

Three more casing volumes will be purged with the sampling pump.

A second TCE detector tube will be used to measure the TCE concentration.

The process will be repeated until an asymptote is reached.

Prior to Each Soil Vapor Monitoring Event Print out the Soil Vapor Pressure Monitoring and TCE Monitoring Field Sheets and

confirm previous rounds of soil vapor monitoring are included on sheet

Confirm adequate inventory of quantitative TCE detector tubes and 1-liter SUMMA canisters

ASPECT CONSULTING

D-2 PROJECT NO. 050067-006-01 APRIL 1, 2008

Prepare field supplies including:

Magnehelic gages

Sampling purge pump (fully charged), detector tube pump, and tubing

Wellhead maintenance supplies

Pressure Measurements After accessing soil vapor monitoring point, confirm that sampling port is closed.

Attach one end of tubing to sampling port, and other end to magnehelic gage.

Ensure magnehelic gage is positioned correctly for accurate reading. Open sampling port and record pressure on field sheet.

TCE Measurements After measuring pressure, connect one end of sampling tubing to sampling port and

other end to sampling pump. Operate pump to purge 3 casing volumes (including the volume of sampling tubing). The casing volumes are calculated and reported on the Soil Vapor Monitoring Field Sheets.

Measure TCE concentration using low-level quantitative detector tube for range of concentrations from previous sampling rounds. Record measurement on field sheet. Dispose of spent detector tubes.

If TCE is not detected at lowest range (125 ppbv), collect soil vapor sample using a 1-L SUMMA canister as follows:

Confirm the valve is closed (knob should already be tightened clockwise) and remove brass cap from canister.

Attach a vacuum gauge, cap the gauge, and briefly open the canister valve to record the initial vacuum of the canister.

Attach the SUMMA canister to the vapor monitoring point and slightly open the canister valve.

Regulate flow to slowly (maximum flow of 250 ml/min) fill the canister. Close valve when vacuum reaches approximately 5 in Hg.

Record final vacuum of canister.

Remove vacuum gauge and replace brass cap.

Fill out canister sample tag and COC.

Close sampling port prior to securing well lid.

After each Soil Vapor Monitoring Event Prepare SUMMA canisters for shipment and Method TO-15 analysis for TCE by Air

Toxics, Ltd.

Transfer field data to electronic data sheets.

ASPECT CONSULTING

PROJECT NO. 050067-006-01 APRIL 1, 2008 D-3

Groundwater Monitoring SOPs The following Standard Operating Procedures (SOPs) are to be followed when performing groundwater monitoring for the Art Brass Plating Interim Cleanup Action. The air sparging system will be temporarily shut down during monitoring.

Prior to each groundwater monitoring event Print out Groundwater Monitoring Field Sheets. Prepare field sheets by labeling each

sheet with the Well ID and the samples to be collected, including type and number of bottles according to the sampling schedule provided in Tables 2 and 3.

Confirm adequate inventory of sampling bottles and field filters.

Prepare field supplies including:

Water level indicator

Flow-through cell (calibrated)

Peristaltic pump (fully charged) and dedicated tubing

Wellhead maintenance supplies

Water level measurements After accessing groundwater monitoring well, remove soil vapor sampling port, if

necessary. Note if pressure is under positive or negative pressure. Allow water level in well to equilibrate, if necessary. Collect and record water level.

Collect groundwater samples Set up groundwater sampling equipment. Dedicated tubing will be stored inside well

monument in a water tight bag.

Using low-flow techniques, purge well until field parameters stabilize. Collect and record field parameter data every 5 minutes. See RI Work Plan for stabilization criteria.

Disconnect flow-through cell from pump for sample collection. Collect water samples, field filtered for dissolved metals analyses, in appropriate type and number of bottles for the desired analysis (see Table below).

Store dedicated tubing inside well monument, reconnect and close soil vapor sampling port, and secure well lid.

Decontamination Decontaminate the water level indicator between wells with Alconox wash and

deionized water rinse.

Transfer wash, rinse, and purge water to the condensate storage tank.

ASPECT CONSULTING

D-4 PROJECT NO. 050067-006-01 APRIL 1, 2008

After each groundwater monitoring event Prepare CVOCs groundwater samples and natural attenuation groundwater samples

for shipment to and analysis by Analytical Resources.

Transfer field data to electronic data sheets.

Table A-1: Groundwater Sampling Guide

Parameter Method Field Filtered

Container Preservative Holding Time

Volatiles 8260B No 2 x 40 mL VOA vials

HCl pH<2 14 days

Dissolved Metals:

Total Iron

Ferrous Iron

Manganese

SM3500 Yes 250 mL amber glass

HCl pH<2 24 hours

Nitrate & Nitrite

Nitrite

353.2 No 500 mL HDPE

H2SO4 28 days

Sulfate 375.2 No 500 mL HDPE

28 days

Alkalinity 310.1 No 500 mL HDPE

Cool 4oC 14 days

Methane, ethane, ethene

RSK 175 No 40 mL VOA vials

Unpreserved 7 days