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Preparation and Implementation of Contamination Assessment Plan for Historical Park Impacted by Former Manufactured Gas Plant Operations

2026-04-02T15:50:26-06:00October 24th, 2009|Tags: |

The City's Confederate Park, a park of historical significance, is located in downtown Jacksonville. The park has been impacted by operations from the former Main Street manufactured gas plant (MGP), operated from 1875 to 1913, when MGP operations reportedly ceased. Coal tar and its constituent PAHs were found in subsurface soils and groundwater. As a result, Florida Department of Environmental Protection (FDEP) NE District issued a Consent Order for Confederate Park, and the City retained Geosyntec to prepare and implement a Contamination Assessment (CA) Plan. The objective of CA was to evaluate hydrogeological conditions, define the distribution of tar and PAHs in the subsurface, characterize release/leaching potentials, predict the transport and fate of dissolved PAHs in groundwater, and provide preliminary evaluations of remedial alternatives.

RCRA Facility Investigation and Groundwater Remediation at the Vehicle Assembly Building

2026-04-02T15:50:53-06:00October 24th, 2009|Tags: |

The Vehicle Assembly Building (VAB) at the Kennedy Space Center (KSC) is the active NASA space shuttle hangar and processing facility. The VAB was constructed in the mid 1960s for the Apollo Space Program and was retrofitted in the mid 1970s to support the Space Transportation System (STS) operations. Geosyntec performed a series of RCRA facility investigations which identified and delineated a chlorinated volatile organic compound (CVOC) plume with a limited trichloroethene (TCE) source area (approximately 1/2 acre), along with a dissolved plume comprised primarily of vinyl chloride in excess of 100 acres. Based upon these findings, NASA asked Geosyntec to prepare a Corrective Measures Study (CMS), a Corrective Measures Design (CMD), and to implement site remedial activities.

Comprehensive Remediation Strategy to Address Soil and Groundwater Contamination at an NPL Site

2026-04-02T15:50:26-06:00October 24th, 2009|Tags: , , , , , |

The 388-acre Hanlin-Allied-Olin NPL site is a former chemical manufacturing complex near Moundsville, West Virginia. The southern portion of the facility produced chloromethane products and used the chlor-alkali (mercury cell) process to manufacture chlorine and sodium hydroxide. The northern portion of the facility produced numerous semi-volatile intermediates for the manufacture of plastics and other synthetic materials. The long-term objective for the site entailed cost avoidance through the proactive development of two significant remedial components: (i) a major removal action using on-site disposal, and (ii) control of chlorinated solvents in an aquifer used downgradient of the site for a municipal water supply. Both objectives related to a third objective of minimizing the Remedial Investigation/Feasibility Study (RI/FS) scope, thereby reducing long-term cost uncertainty.

Comprehensive Remediation and Construction for LNAPL Plume Remediation

2026-04-02T15:50:52-06:00October 24th, 2009|

In 2002, the Federal Reserve Bank broke ground on a four-story, 280,000-square-foot facility on the former Jefferson Davis Memorial Hospital site in Houston, scheduled for completion in 2005. A gasoline plume from an off-site City of Houston vehicle maintenance facility threatened to disrupt construction, as previously installed recovery systems were still in place.

Bioremediation of Chlorinated Solvents in Fractured Bedrock at the Caldwell Trucking NPL Site

2026-06-16T14:30:03-06:00October 24th, 2009|Tags: , |

The Caldwell Trucking Site consists of properties and groundwater contaminated by the disposal of residential, commercial, and industrial septic waste. Since 1981, over 300 private wells in the area have been taken out of service due to contamination, and the affected residences have been connected to the municipal drinking water supply system. The area of groundwater contamination is within fractured bedrock, and is contaminated with trichloroethylene and its associated biodegradation products (e.g., cis-1,2-dichloroethene and vinyl chloride) and 1,1,1-trichloroethane. The original Record of Decision stipulated that a groundwater recovery system (pump and treat) be installed at the facility. In February 1997, the U.S. EPA modified the groundwater remedial action schedule, allowing the PRPs to test the effectiveness of a permeable iron reactive barrier to intercept the contaminated groundwater before it discharges at a surface water seep. Monitoring results on the effectiveness of the iron wall indicated the wall reduced the volatile organic compound (VOC) levels in the seep but not to acceptable levels. As a result, additional treatment to reduce the levels of contamination reaching the seep was needed.

In Situ Bioaugmentation for the Remediation of TCE and TCA DNAPL at a Metal Finishing Operation

2026-06-16T14:30:15-06:00October 24th, 2009|Tags: |

The primary manufacturing processes at Crown Risdon's 11.5-acre former Cosmetic Container Division Facility involved metal finishing operations. This resulted in the groundwater becoming contaminated primarily with chlorinated solvents, specifically chlorinated ethenes and ethanes such as 1,1,1-trichloroethane (TCA); trichloroethene (TCE); tetrachloroethene (PCE); cis-1,2-dichloroethene (cis-DCE), 1,1-DCE; and 1,1-dichloroethane (DCA). The two areas of concern are a former lagoon area and the former metal finishing area, each of which has high levels of chlorinated ethenes and ethanes at concentrations in groundwater that suggest the presence of dense non-aqueous phase liquid (DNAPL). Concentrations as high as 65 ppm TCA and 26 ppm TCE have been measured in the groundwater at this facility.

Feasibility Study of Enhanced In Situ Bioremediation for a Mixed Chlorinated Solvent Source Area

2026-04-02T15:50:53-06:00October 24th, 2009|Tags: |

Shallow and mid-depth groundwater beneath Operable Unit 11 (OU 11) on Naval Air Station (NAS) North Island is contaminated with a concentrated (hundreds of parts per million) mixture of chlorinated solvents including 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethene (TCE). A portion of the contamination is likely present as a dense nonaqueous phase liquid (DNAPL). The Navy is performing an Engineering Evaluation/Cost Analysis (EE/CA) evaluating enhanced in situ bioremediation (EISB) and high-temperature in situ thermal desorption (ISTD) as final remedies for the Site.

Comprehensive Remediation and Design/Build Services at a Buried Drum Site

2026-06-16T14:30:22-06:00October 24th, 2009|Tags: |

The 6-acre St. Germain Site in Taunton, Massachusetts had formerly been used as a heavy equipment staging and storage area. The former site owner operated a waste hauling business and had buried drums and impacted soils on the property from multiple offsite sources. In 1999, U.S. EPA initiated a Time Critical Removal Action at the site and subsequently excavated over 700 drums from the subsurface. In May 2000, the property owner and a nearby manufacturer were issued an Administrative Order on Consent (AOC) by the U.S. EPA and later a Notice of Responsibility (NOR) by the MassDEP. The corporate successor of that firm retained Geosyntec to perform an initial site investigation at the site in 2000. Geosyntec provided oversight for the AOC and NOR mandated excavation of 4,000 buried drums and 12,000 cubic yards of soil. During these activities, a complex mix of contaminants was identified, including petroleum hydrocarbons, chlorinated ethenes and benzenes, a number of other volatile and semi-volatile organic compounds, and proprietary chemicals.

Site Assessment and Comprehensive Remedial Strategy using Phytotechnology at a Former Wood Treating Facility and Sawmill

2026-04-06T11:37:17-06:00October 24th, 2009|Tags: |

The plant site was a former wood treating facility and sawmill that dates back to the 1950's. Wood-treating operations ceased around 1980, and a residential/commercial building material supplier currently uses the facility. Previous work, initiated in 1986, included site assessment and/or corrective action activities (i.e., source removal efforts), which continue to the present. The major contaminants of concern in soils are arsenic and dioxin (expressed as 2,3,7,8-TCDD Toxicity Equivalents), while groundwater below parts of the site is impacted by arsenic. Historically, Pentachlorophenol has been found in groundwater in very isolated areas, but has been naturally attenuated following the source removal efforts. Southern Wood Piedmont (SWP) retained Geosyntec to conduct additional site assessment activities, and to develop a comprehensive remedial strategy to resolve remaining on- and off-site issues. The property was divested in 2006; however, Rayonier is responsible for historic offsite releases.

In Situ Chemical Oxidation of TCE in Fractured Bedrock

2026-04-06T11:39:22-06:00October 24th, 2009|Tags: , , |

At this site, TCE DNAPL is present in highly fractured bedrock that is currently used by the local municipality as a drinking water supply. In summer 2001, the U.S. EPA issued a Preferred Remedial Action Plan (PRAP) for the site, primarily consisting of pump and treat remedy components for both the source area and the plume. The Client retained Geosyntec to demonstrate to U.S. EPA and the Pennsylvania Department of Environmental Protection (PADEP) that pump and treat would not result in remediation of the source area within any reasonable timeframe.

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