SURFAC

Type of Facility:   Former Service Stations (2)

Location:              Norman, Oklahoma

 Releases from two former UST sites created a very large plume beneath multiple businesses, a state highway, and threatened nearby residences. The SPH plume was estimated to be 550 feet by 250 feet (> 2 acres) and the benzene plume 700 feet by 400 feet (>5 acres). EcoVac Services mobilized multiple treatment units and arrived onsite within one day of contract execution. SURFAC^® was implemented to remove the SPH and ISCO-EFR^® was subsequently utilized to reduce dissolved benzene concentrations. The SPH was removed within 45 days (May to July 2007). Dissolved benzene has been reduced below corrective action levels across most of the entire plume. SPH remains absent 13 months after implementation.

 

Type of Facility:   Former Hospital

Location:              Tucker, Georgia

A diesel fuel release emanated from a product line leading from a storage tank to an emergency power generator at a (former) hospital. Eight monitor/recovery wells contained separate-phase diesel fuel, ranging in thicknesses from 0.95 feet to 4.00 feet (maximum aggregate thickness of 20.16 feet). Depth to water ranges from 20 to 25 feet below ground surface in the surficial aquifer that exists within saprolite.

The client attempted multiple remedies to remove the SPH. Four EFR^® events reduced SPH by 36% over a five-month period in 2001. Approximately four years of product skimming and total fluids recovery resulted in an additional SPH reduction of 57%. Four additional EFR^® events were subsequently implemented over a ten-month period in 2006-07, resulting in an incremental SPH reduction of 36%. An aggregate SPH thickness of 2.52 feet persisted at this point in five monitor/recovery wells.

EcoVac Services was contracted to institute its patented SURFAC^® process at this site in March 2007.  Two SURFAC^® events were implemented from March and June 2007. The SPH thickness has been reduced to 0.09 feet in a single well, representing a 96% reduction as compared to pre-SURFAC^® levels of SPH. The presence of SPH in this single well may be the consequence of a drought-induced historic low water table.

The incremental reductions in SPH thickness are summarized below:

 

 Remedial Method                                  Incremental SPH Reduction                                 Time Period

EFR^® (four 8-hr events)                     36% (from 14.12 feet to 9.09 feet)                  March 2001-August 2001

Skimming/ total fluids recovery          57% (from 9.09 feet to 3.93 feet)                    2001-2006

EFR^® (four 8-hr events)                     36% (from 3.93 feet to 2.52 feet)                    April 2006-February 2007

SURFAC^® (two events)                     60% (from 2.52 feet to 1.00 feet)                    March/June 2007

 

Type of Facility:   Inactive Service Station

Location:              Nashville, Tennessee

EcoVac Services was contacted by the Tennessee DEC to remove SPH from two monitor wells that historically contained SPH (gasoline).  The subsurface consisted of limestone at less than two feet below grade.  Water levels in the monitor wells are fracture controlled, as evidenced by the range of groundwater elevations (ranging from 3 to 30 feet). Although SPH was not detected prior to the SURFAC^® Pilot Test Event conducted in August 2005, this event did mobilize SPH into MW-9 (0.25 feet) prior to the Surfactant Injection Event.  Following the removal of SPH, site closure was achieved.

 

Type of Facility:   Service Station

Location:              Clarksville, Tennessee

EcoVac Services was contacted by the Tennessee DEC to remove SPH (gasoline) from the subject site.   Historically, SPH had been present in five monitor well and four tank field wells.  Two SURFAC applications were implanted in August and December 2005.  Although SPH did return to the tank field observation wells, it was observed that the UST system did not possess overspill protection, resulting in overspills during gasoline deliveries.

 

Type of Facility:   Inactive Service Station

Location:              Martinsville, Virginia

EcoVac Services was contacted by the Virginia DEQ to remove SPH from two monitor wells that historically contained SPH (gasoline).  The primary driver for this site was the presence of MTBE in a downgradient spring. Depth to water was 12 feet and the surficial aquifer consisted primarily of a silty clay. SURFAC^® was conducted in November 2005.  SPH has not returned.    

 

Type of Facility:   Inactive Service Station

Location:              Chase City, Virginia

EcoVac Services was contacted by the Virginia DEQ to remove SPH from a site that historically contained SPH.  Two monitor well containing SPH at thicknesses of 0.06 and 0.22 feet was present prior to the SURFAC^® Pilot Test Event.  The aquifer was present in a silty clay aquifer in the Piedmont. A SURFAC^® Pilot Test Event, Surfactant Injection Event, two Surfactant Capture Events and a Surfactant Polishing Event were conducted in March to April 2006.  A 90% reduction in SPH (0.02 feet in one monitor well) was achieved. 

 

Type of Facility:   Inactive Service Station

Location:              Danville, Virginia

EcoVac Services was contacted by the Virginia DEQ to remove SPH from a site that historically contained SPH in two monitor wells.  Previous remedial activities consisted of hand bailing and 11 MPE events by another provider.  A SURFAC^® pilot test event, injection event, and three capture events were conducted in March to April 2006.  SPH was reduced in two monitor wells from thicknesses of 0.14 and 0.30 feet to approximately 0.25 feet in one well.

 

Type of Facility:   Andrews Air Force Base

Location:              Camp Springs, Maryland

EcoVac Services’ patented A SURFAC^® process was utilized at the subject site where SPH (JP-4 and aviation gas) had historically been present in five wells as a result of a leaking SUT system associated with pre-1961 fueling activities.  The areal extent of SPH was approximately 26,500 feet².  Prior remedial efforts had removed only three gallons of SPH.

SURFAC^® was implemented over a ten-day period in April and May 2006 and reduced SPH thicknesses in five wells ranging in thickness from 0.09 to 0.93 feet to SPH being present in two wells (0.01 and 0.03 2 feet) approximately one year later.

 

Type of Facility:   Service Station

Location:              Huntsville, Alabama

As much as 7.05 feet of SPH (gasoline/diesel fuel mix) were present in two wells for several years. Four EFR^® events reduced the SPH to a sheen. SURFAC^® was implemented in December 2006 at the site, resulting in the complete removal of SPH.

 

Type of Facility:   Former Pipeline Site

Location:              Baltimore, Maryland

SPH had historically been present in several wells at this highly permeable site located near Curtis Bay/Patapsco River.  Depth to water ranged from 35 to 45 feet. Two SPH (gasoline) plumes measured nearly 250 feet in length. Two SURFAC^® Pilot Test Events conducted in May 2006 reduced SPH in three wells ranging in thickness from 0.01 to 0.80 feet (aggregate thickness 1.56 feet) by over 60%.  Vacuum influence was observed nearly 200 feet distant from the extraction wells. SURFAC^® completely removed SPH and site closure was achieved.

 
 

Type of Facility:   Former Bulk Plant

Location:              Watervliet, Michigan

Approximately 92,000 gallons of gasoline was released in the vicinity of the subject property in 1948. The subsurface at the site consists of a highly variable glacial till. Depth to groundwater ranges from 20 to 25 ft.  An investigation conducted in 2000 revealed the presence of SPH at the site. SPH collection events were performed from November 2000 through September 2002, at which time an interim SPH recovery system (down hole bladder pump) was installed. The recovery system had collected approximately 316 gallons of SPH.

SPH was present in five monitor wells, with thicknesses ranging from 0.02 feet to 1.05 feet (2.83 ft aggregate) during four EFR^® events conducted by EcoVac Services from June through October 2006.  These EFR^® events reduced SPH thicknesses to 0.20 feet in two wells at a cost of $15,561, inclusive of fluid disposal.

SURFAC^® was implemented over a four-day period from November 2006 through January 2007, involving the injection and recovery of 1,800 gallons of diluted surfactant mixture at five monitor wells. SPH was completely absent for over one year.  EFR^® was used to remove small quantities of SPH that appeared 15 months after SURFAC^®.  The reappearance of SPH may have been due to the inability of the surfactant aqueous solution to come into contact with SPH trapped in or around fill material, foundations or utility conduits present under the current building and roadway.  The site is currently being evaluated for site closure.

 

Type of Facility:   Construction Maintenance Shop

Location:              Oklahoma City, Oklahoma

EcoVac Services, Inc. was contracted by an environmental firm under the direction of the Oklahoma Corporation Commission (OCC) to remove SPH (diesel fuel) that had emanated from the diesel fuel UST tank field.  The site is underlain by clayey silty sand at the surface, grading into silty, fine-grained sand at approximately 15 feet bgs. then coarsening into a medium grained sand at 25 feet bgs. The groundwater table fluctuates between 17 to 22 feet bgs during the year.

EcoVac designed the remediation well network and provided oversight during installation. The remediation well network consisted of 18 remediation wells and 5 tank pit remediation wells. Remediation field activities were then initiated on October 24, 2007 (EFR^®), and continued through November 16, 2007.  SPH did not return and the OCC issued site closure.

 

Type of Facility:   Former Trolley and Bus Terminal

Location:              Cincinnati, Ohio

Business activities at this site since the early 1900s have resulted in soil and groundwater contamination from diesel fuel and gasoline releases.  SPH covered an area of approximately 10,000 square feet.  Previous remedial activities (excavation of all underground storage tanks, a “pump and treat” system, and 12 mobile dual-phase/multi-phase extraction events performed by another provider) failed to remove SPH from the site.

Groundwater is present in a confined bedrock aquifer that consists of a weathered limestone and shale at depths ranging from approximately 20 to 37 feet below grade.  The bedrock surface at this site is variable and undulating and overlain by silty clay. Static groundwater levels, ranging from approximately 15 to 28 feet below grade in each well are present above the monitor well screens, possibly due to the hydrostatic pressure pushing the water above the top of the bedrock surface.

EcoVac Services was contacted to implement SURFAC^® at this site due to the challenging conditions (i.e. geology/hydrogeology conditions, extent of SPH plume, and ongoing presence of SPH despite previous remedial attempts) and lack of funds the owner of the site was able to spend.  SPH was present in four monitor wells in thicknesses ranging from 0.02 to 0.13 feet prior to the SURFAC^® pilot testing.  SPH (0.55 feet) was mobilized into a monitor well that had never contained SPH following the pilot testing.

The addition of three monitor wells as well as additional EFR^® were recommended at this site; however, due to the lack of funds the site owner was able to spend at the site, SURFAC^® was implemented.  The additional monitor wells would have allowed for more complete coverage of the surfactant/water mixture to come into contact with the SPH.  Additional EFR^® events were recommended in order to mobilize more SPH toward the extraction wells and further reduce SPH thicknesses at the site.  SURFAC^® did reduce SPH to a thickness of < 0.04 feet in one monitor well.

 

Type of Facility:   Rental Truck Facility

Location:              Del City, Oklahoma

EcoVac Services, Inc. was contracted by an environmental consulting firm under the direction of the Oklahoma Corporation Commission (OCC) to remove SPH (gasoline) at a rental truck facility. The SPH plume emanated from a gasoline UST tank field and fuel island, located at opposite sides of the property and covered an area of approximately 250 feet by 150 feet, and 13,900 yd³. The site is underlain by clay, silty clay, and sandy clay, with occasional clayey sand lenses. The groundwater table fluctuates from 7 to 17 feet bgs. Groundwater flow rates are approximately 10^-4 to 10^-6 cm/s. The contamination (smear zone) lies between 5 to 18 feet bgs, in interbedded clay, silty clay, sandy clay, and thin clayey sand lenses.

EcoVac designed the remediation well network, consisting of 18 wells, and provided oversight during installation.  SPH was present in seventeen monitor wells ranging in thickness from 0.03 to 2.39 feet prior to the implementation of EFR^® and SURFAC^® activities.  EFR^® was implemented for two weeks in January and February, 2008 to reduce SPH thicknesses and reduce the area of hydrocarbon contamination. SURFAC^® was implemented in February through March, 2008 to completely remove the SPH.   SPH was completely removed from the site and site closure was achieved.

 

Type of Facility:   Library Parking Garage

Location:              Fort Wayne, Indiana

Approximately 3,300 gallons of diesel fuel were released from a diesel fuel line connecting the diesel fuel tank to the site’s generator in November 2006.  The release was located in an underground library parking garage.  Prior to EcoVac Services’ patented SURFAC^® process, SPH covered an area of approximately 1,500 square feet.  Previous remedial activities have removed approximately 2,200 gallons of diesel fuel utilizing double diaphragm pumps in the two and four-inch monitor wells.

EcoVac Services was contacted to implement SURFAC^® at this site due to the challenging conditions (i.e. access, geology/hydrogeology conditions, extent of SPH plume, and ongoing presence of SPH despite previous remedial attempts). Historically, SPH has been present in seven monitor wells.  SPH was detected in one monitor well prior to SURFAC^® pilot testing. SURFAC^® pilot testing mobilized SPH into seven monitor wells.  SPH may have been trapped in areas around utility lines and foundations and permeable fill material.

SURFAC^® was conducted at the subject site in June and July 2008.  The site is being evaluated for site closure.

 

Type of Facility:   Former Rubber Manufacturing Plant

Location:              Madison, Tennessee

Piping leaks to an aboveground tank and oil/water separator are believed to have resulted in a SPH (Stoddard solvent) plume, which covered an area of over 20,000 square feet.  Groundwater is present in a limestone bedrock aquifer at depths ranging from approximately 10 to 40 feet below grade.  The bedrock aquifer is overlain by silty clay. 

Nine extraction wells were installed prior to EFR^® activities.  SPH, ranging in thicknesses from 0.03 to 9.24 feet, was present in 12 wells during ten EFR^Ò activities conducted from March 2007 to December 2007.  Ten EFR® events reduced SPH to three wells, ranging in thicknesses from 0.10 to 0.89 feet, a 92% reduction.  SURFAC^®, conducted in September and October 2009, removed SPH in all of the treatment wells.  The wells in the area of concern have been abandoned per state directive.

 

Type of Facility:   Service Station

Location:              Oklahoma City, Oklahoma

EcoVac Services was retained to remove SPH at the subject site after a prominent surfactant remediation firm failed to do so.  SPH covered an area of approximately 5,000 square feet and ranged in thicknesses from 0.15 to 5.28 feet in nine wells prior to the previous firm’s remediation efforts.  Post remediation efforts resulted in increased SPH thicknesses across the site at a cost of $291,270.  The SPH plume increased to approximately 7,250 square feet, SPH thicknesses averaged an increase of 0.73 feet across the site, and SPH had appeared in four additional wells for the first time.  Previous remediation also left an in-situ emulsified groundwater/hydrocarbon mixture.

The previous remediation firm proposed an additional $310,337, excluding a proposed installation of 40 additional wells, after its failure to remove SPH at the site. EcoVac implemented EFR^® and SURFAC^®® was initially implemented March 5 to 15, 2009 to reduce the size and thickness of the SPH plume.  SURFAC^® was then implemented from March 16, 2009 to May 1 2009 to completely remove SPH.  SPH and in-situ emulsion was completely removed from site within 57 calendar days (34 field days) of implementation at a cost of $263,000 (Guaranteed cleanup contract).