WORK PLANS_FILE 1 - Laserfiche WebLink

Home Browse Search

Geologicall rechaks/etc. Page 7 Additional Pilot Test Work Plan Project No.770.2 . October 30,2008 4.0 DUAL PHASE EXTRACTION TEST Soil vapor extraction and groundwater extraction are two proven technologies for the remediation of gasoline impacted sites. Dual phase extraction involves the use of high vacuurn_technology to simultaneously extract groundwater and soil vapor from one well. By r' inducing a cone of depression-by-extracting groundwater, additional- vadose zone soil is exposed to vapor extraction. For the Purpose of-this—pilot test, GTI,proposes to,utilize V a� mobile -treatment unit-for a-period•-of tvGo weeks? Extracted vapors will .be treated-with a> thermal oxidizer and groundwater wilfbe stored in a trailer.and hauled off site-for=disposal. <Y4 -_. .t c _ - - . _ -- GTI-will attempt to minimize groundwater extraction(except in MW-5) and apply the full vacuum to the vadose zone. Groundwater samples (influent to the knock out tank) will be collected forestimating .the, ,,,contaminant-..mass`-removal, Groundwater samples;will be analyzed for the following compounds: :-- .. -} • TPH-Dg _usin EPA Method 8015M - _ _ • TPH-G using EPA Method 8260 • BTEX using EPA Method 8260 r `-F Vapor samples are-also Collce ted-for'estimating the contaminant mass removal in vapor �� phase. Vapor samples are analyzed for the following_compounds: Z • TPH-D,using EPA Method 80 SM"samples will be collecteAdn charcoal tubes-i 0"�7 2 • TPH G using EPA Method TO-3, samples will be collected in,/Soma 1 anister • BTEX•using EPA Method TO-3 samples will be collected infSoma anister ' Over the course of this tvyo.week.dual phase_pilottest at least,,6 groundwater.samples-and�G'� vapor samples will be collected. 4.1 Extraction Wells The existing monitoring we110_(M-W---5)' and new -b_ioventing wells (EW-1 and EW-101) installed for_previous pilot test(November-December 2007) will be utilized 4.2 Dual Phase Extraction System The general process for dual phase extraction is as follows: ■ Extract vapors and water using a liquid ring vacuum pump. ■ Separate the influent vapors and water in a portable vacuum tank. ■ The contaminated vapor is then oxidized in a thermal oxidizer. ■ The captured contaminated groundwater is transferred to a tanker truck trailer via a high vacuum pump. The tank trailer will be emptied at regular intervals by a licensed hauler for transportation to a waste disposal facility.