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High Resolution Site Characterization Approach: Rapid Sample Collection with High Quality Analyses Targeting VOCs/SVOCs Presented by: Harry O’Neill, President Beacon Environmental Services, Inc. Pablo Yoshikawa, Project Manager CH2M Hill -- São Paulo 01 October, 2014
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Project Location Source:
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Historical Background Large manufacturing facility that was in the process of being decommissioned Manufactured chemicals from 1980s to 2014 Broad range of products manufactured including aromatic hydrocarbons, multiple chlorinated chemicals, and nitroaromatics Numerous compounds of concern at site that had been identified in prior sampling. Primary compounds of concern were chloroanilines and chlorobenzenes.
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Objectives and Site Conditions OBJECTIVES: Use high resolution passive soil gas survey to identify source areas and lateral extents of known contaminants, as well as determine what other compounds are present with mass spectrometry analyes. Identify which compounds are present to guide the health and safety program and protect site workers during sampling and remediation. Guide where to collect soil and groundwater data and to strategically guide the membrane interface probe (MIP) and hydraulic profiling tool (HPT) sampling. Soils: sand with embedded clays and silts at 0 – 15 m Groundwater: water table at 12 - 15 m; aquitard at 55 m Conditions: site receives frequent rain events
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Scope of Work NAPL known to be present. Potential for very high concentrations in soil vapor at some locations. CH2M and their client elected to first collect samples over a 24-hour exposure period and then immediately after to collect samples over a 14 day sampling period. Areas with known NAPL were not sampled.
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Scope of Work NAPL known to be present. Potential for very high concentrations in soil vapor at some locations. CH2M and their client elected to first collect samples over a 24-hour exposure period and then immediately after to collect samples over a 14 day sampling period. Areas with known NAPL were not sampled.
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Aerial View of Site Source:
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Sampling Plan
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Target Compounds (5-pt calibration)
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Passive Soil Gas Samplers provided in a Kit Sample Collection Kit Samplers shipped in Tool Box Dimensions: 50 cm x 25 cm x 25 cm Shipped with custody seal Custom packaged Detailed kit instructions and installation videos
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Passive Soil Gas Samplers provided in a Kit Sample Collection Kit Samplers shipped in Tool Box Dimensions: 50 cm x 25 cm x 25 cm Shipped with custody seal Custom packaged Detailed kit instructions and installation videos
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Passive Soil Gas Samplers Passive Soil Gas Sampler Actual size: 18 mm x 60 mm Two types of adsorbents Uniform mass of adsorbents used (verified with analytical balance) Adsorbents are hydrophobic Completely inert sampler Design compliant with ASTM Standards D5314 and D7758
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Pictures of Sampler Installation
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Installation Procedures Samplers were installed in 2 cm diameter holes advanced to a 1 m depth Aluminum sleeves (2.5 cm x 30 cm long) were used to protect the samplers from contaminant in gases that can migrate laterally in the more porous subgrade material beneath the surfacing.
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Target Compounds (5-pt calibration)
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Target Compounds Identified
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14-Day Survey: Non-Target Compounds and TICs TIC = Tentatively Identified Compound
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Shipment of Samples to Laboratory Shipped: FedEx Priority Delivery Both shipments delivered in 1 business day to Beacon’s laboratory in United States
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Analysis by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) following EPA Method 8260C Analytical results based on 5-point initial calibration Internal standards and surrogates included with each analysis Daily continuing calibration checks Laboratory control samples System daily tunes Method blanks Method Detection Limit (MDL) Studies Limit of Detection and Quantitation (LOD and LOQ) Studies Meets requirements of Level III/Level IV data quality objectives Analytical Method QC Procedures
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Findings
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Findings: 1-Day Exposure Period Survey
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Findings: 14-Day Exposure Period Survey
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Findings: 1-Day Exposure Period Survey
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Findings: 14-Day Exposure Period Survey
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Findings: 1-Day Exposure Period Survey
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Findings: 14-Day Exposure Period Survey
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Findings: Analysis of Sample Location B-59 Sample Location: B-59 TOTAL CHLOROBENZENES
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Findings: Comparing Results between Two Surveys
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Additional Compounds Adsorbed – 14-Day Survey
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Soil and Groundwater Data near PSG B-59 PSG Sample Location: B-59
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Soil Data near PSG B-59
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Groundwater Data near PSG B-59
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Conclusions Passive soil gas survey met the objectives of determining what compounds were present in the soil and groundwater even when 70+ different compounds of concern were identified from 1,2-dichloroethane (C 2 H 4 Cl 2 -- MW=98.96) to pentachlorobenzene (C 6 HCl 5 -- MW=250.34) All PSG survey “hot spots” confirmed to be locations with high concentrations of contamination including NAPL. Passive samplers were easy to transport and ship internationally. Plus, collection of the samples required only a small rotary hammer drill and hand tools that were easily sourced locally. Dichloroanilines and a range of chloro- & nitrobenzenes were identified in soil gas, which had excellent agreement with what was expected based on historical activities and prior data. The PSG survey significantly reduced the number of required soil and groundwater samples and allowed for a focused and guided sampling program that included a MIP survey for vertical delineation of VOCs.
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Thank you! BEACON… We can be your guide Obrigado! ACCREDITATIONS: Laboratory Analyses: ISO/IEC 17025 & U.S. DoD ELAP Sampler Manufacturing and Shipment: TNI NEFAP Harry O’Neill Beacon Environmental Services, Inc. Forest Hill, MD USA 1-410-838-8780 Harry.ONeill@beacon-usa.com www.beacon-usa.com
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