Remediation Status: Site closed

Why the technology was selected:
Bioremediation selected, although the site was not a perfect candidate, due to proximity of water to surface and residential property use. Bioremediation- sodium lactate and 3DMe

Date implemented:
Feb 2004

Final remediation design:
Remedial Design 2004 Soil was excavated from the interior of the building in the locations of the former drycleaning machines (2 locations) and from the exterior (north) where the former USTs were located. On completion of the excavations injection galleries were installed in the pits prior to backfilling with clean fill and re-concreting. A total of 121 tons of soil was disposed of as Special Waste. 2). MEME events(2)were conducted in March 2004 and Novmember 2004. - MEME: Two 4-inch extraction wells (EW-2 and EW-2) were installed into the bedrock to a depth of 31 feet bgs and screened from 6 to 30 feet bgs. These wells and groundwater monitoring wells,MW-1/MW-2 MW-4/MW-5/MW-6, were then used to conduct the MEME events. -Both extraction events were conducted over two consecutive 8 hour days. -Mobile treatment unit was configured for thermal treatment of VOC extracted vapors. Extracted groundwater was contaminated with vinyl chloride and petroleum hydrocarbons. Feb 2005: 1st Injection Event,711 gallons of 20% sodium lactate and 2 gallons of Miracle-Grow solution- gravity fed into the three injection galleries and EW-2 along with 550 gallons of water. Oct 2006: 2nd Injection Event(Prior to this event taking place 6 additional infiltration galleries were installed onsite) 330 gallons of 60% sodium lactate, 990 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. Jan 2007: 3rd Injection Event, 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. July 2007:4th Injection Event- 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. April 2008: 5th Injection Event - 220 gallons of 60% sodium lactate, 660 gallons of dilution water were injected into the galleries and MW-3. 6).April 2008: 6th Injection Event- Prior to this event three injection wells IW-1, IW-2 and IW-3 were installed (north exterior) in an area hydrologically upgradient of existing points because existing radius of influence was not reaching MW-9 area. These 6-inch wells were advanced to 38.5, 36.0 and 38.0 feet bgs. The upper 20 feet of each well was completed with the remaining length remaining unfinished. The upper annular space between the PVC pipe and the boring wall was then sealed with packers and then bentonite. Once the wells had set 3DMe Solution was injected into them, and three of the injection galleries and MW-3 and MW-9 (after injection wells must be surged to ensure amendment is clear of the well). A total of 1,891 gallons of the 3DMe solutions mixed with dilution water was injected into these points over a period of 5-days in April and May 2008.

Results to date:
Pre-remediation contaminant levels: February 2004 PCE - 1.2 mg/L TCE - 0.49 mg/L DCE - 4.8 mg/L VC - 3.2 mg/L Post-injection contaminant levels: October 2008 (Last sampling event) PCE - .020 mg/L TCE - .004 mg/L DCE - .360 mg/L VC - .001 mg/L

Next Steps:
Site closure October 8, 2009

Why the technology was selected:
Mobile Enhanced Multi-phase Extraction (MEME) - This technology was selected to remove contaminantion in the vadose and top of water zone.

Date implemented:
Feb 2004

Final remediation design:
Remedial Design 2004 Soil was excavated from the interior of the building in the locations of the former drycleaning machines (2 locations) and from the exterior (north) where the former USTs were located. On completion of the excavations injection galleries were installed in the pits prior to backfilling with clean fill and re-concreting. A total of 121 tons of soil was disposed of as Special Waste. 2). MEME events(2)were conducted in March 2004 and Novmember 2004. - MEME: Two 4-inch extraction wells (EW-2 and EW-2) were installed into the bedrock to a depth of 31 feet bgs and screened from 6 to 30 feet bgs. These wells and groundwater monitoring wells,MW-1/MW-2 MW-4/MW-5/MW-6, were then used to conduct the MEME events. -Both extraction events were conducted over two consecutive 8 hour days. -Mobile treatment unit was configured for thermal treatment of VOC extracted vapors. Extracted groundwater was contaminated with vinyl chloride and petroleum hydrocarbons. Feb 2005: 1st Injection Event,711 gallons of 20% sodium lactate and 2 gallons of Miracle-Grow solution- gravity fed into the three injection galleries and EW-2 along with 550 gallons of water. Oct 2006: 2nd Injection Event(Prior to this event taking place 6 additional infiltration galleries were installed onsite) 330 gallons of 60% sodium lactate, 990 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. Jan 2007: 3rd Injection Event, 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. July 2007:4th Injection Event- 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. April 2008: 5th Injection Event - 220 gallons of 60% sodium lactate, 660 gallons of dilution water were injected into the galleries and MW-3. 6).April 2008: 6th Injection Event- Prior to this event three injection wells IW-1, IW-2 and IW-3 were installed (north exterior) in an area hydrologically upgradient of existing points because existing radius of influence was not reaching MW-9 area. These 6-inch wells were advanced to 38.5, 36.0 and 38.0 feet bgs. The upper 20 feet of each well was completed with the remaining length remaining unfinished. The upper annular space between the PVC pipe and the boring wall was then sealed with packers and then bentonite. Once the wells had set 3DMe Solution was injected into them, and three of the injection galleries and MW-3 and MW-9 (after injection wells must be surged to ensure amendment is clear of the well). A total of 1,891 gallons of the 3DMe solutions mixed with dilution water was injected into these points over a period of 5-days in April and May 2008.

Results to date:
Pre-remediation contaminant levels: February 2004 PCE - 1.2 mg/L TCE - 0.49 mg/L DCE - 4.8 mg/L VC - 3.2 mg/L Post-injection contaminant levels: October 2008 (Last sampling event) PCE - .020 mg/L TCE - .004 mg/L DCE - .360 mg/L VC - .001 mg/L

Next Steps:
Site closure October 8, 2009

Why the technology was selected:
Excavation - Soil source area removal: Due to the shallow soil horizon at this site it was determined that removing soil from under the building and in the areas of the former solvent USTs was the most cost effective way to treat the soil contamination.

Date implemented:
Feb 2004

Final remediation design:
Remedial Design 2004 Soil was excavated from the interior of the building in the locations of the former drycleaning machines (2 locations) and from the exterior (north) where the former USTs were located. On completion of the excavations injection galleries were installed in the pits prior to backfilling with clean fill and re-concreting. A total of 121 tons of soil was disposed of as Special Waste. 2). MEME events(2)were conducted in March 2004 and Novmember 2004. - MEME: Two 4-inch extraction wells (EW-2 and EW-2) were installed into the bedrock to a depth of 31 feet bgs and screened from 6 to 30 feet bgs. These wells and groundwater monitoring wells,MW-1/MW-2 MW-4/MW-5/MW-6, were then used to conduct the MEME events. -Both extraction events were conducted over two consecutive 8 hour days. -Mobile treatment unit was configured for thermal treatment of VOC extracted vapors. Extracted groundwater was contaminated with vinyl chloride and petroleum hydrocarbons. Feb 2005: 1st Injection Event,711 gallons of 20% sodium lactate and 2 gallons of Miracle-Grow solution- gravity fed into the three injection galleries and EW-2 along with 550 gallons of water. Oct 2006: 2nd Injection Event(Prior to this event taking place 6 additional infiltration galleries were installed onsite) 330 gallons of 60% sodium lactate, 990 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. Jan 2007: 3rd Injection Event, 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. July 2007:4th Injection Event- 220 gallons of 60% sodium lactate, 675 gallons of dilution water and 24 pints of Miracle-Grow were injected into the galleries. April 2008: 5th Injection Event - 220 gallons of 60% sodium lactate, 660 gallons of dilution water were injected into the galleries and MW-3. 6).April 2008: 6th Injection Event- Prior to this event three injection wells IW-1, IW-2 and IW-3 were installed (north exterior) in an area hydrologically upgradient of existing points because existing radius of influence was not reaching MW-9 area. These 6-inch wells were advanced to 38.5, 36.0 and 38.0 feet bgs. The upper 20 feet of each well was completed with the remaining length remaining unfinished. The upper annular space between the PVC pipe and the boring wall was then sealed with packers and then bentonite. Once the wells had set 3DMe Solution was injected into them, and three of the injection galleries and MW-3 and MW-9 (after injection wells must be surged to ensure amendment is clear of the well). A total of 1,891 gallons of the 3DMe solutions mixed with dilution water was injected into these points over a period of 5-days in April and May 2008.

Results to date:
Pre-remediation contaminant levels: February 2004 PCE - 1.2 mg/L TCE - 0.49 mg/L DCE - 4.8 mg/L VC - 3.2 mg/L Post-injection contaminant levels: October 2008 (Last sampling event) PCE - .020 mg/L TCE - .004 mg/L DCE - .360 mg/L VC - .001 mg/L

Next Steps:
Site closure October 8, 2009