Verdantas (formerly Project Navigator, Ltd.) is the Project Coordinator for the Tex Tin Superfund Site in Texas City, Texas, a 140-acre former tin and copper smelter. Tex Tin hosted the only tin smelter operating in the US during WWII. Verdantas was retained by the 30-member PRP group to serve as Project Coordinator (PC). As PC we developed a design/build strategy for the remediation and oversaw the RD/RA and ongoing O&M and Focused Feasibility Study (FFS). The project was completed from 2000 – 2003, ahead of schedule, at a cost below the ROD estimate, and with no safety incidents. Region 6 EPA called the project a “Superfund Success Story”. 

The design/build approach involved dividing plans and work into separate phases. This allowed construction, investigation, design, and work plan preparation to occur concurrently, minimizing the schedule and using knowledge gained in early work to inform subsequent work. Criteria considered included: weather, construction sequence, resource availability, stakeholder requirements, cash flow, safety and schedule. 

The initial work plan included base documents such as the Pre-Design Investigation, H&S Plan, QA/QC Plan, Sampling Plan, Decontamination Plan, Waste Management Plan and others to serve throughout the project. 

Subsequent work plans included: 

Phase I

• Asbestos abatement 
• Lab pack of 6,000 pounds of 150 hazardous chemicals including potentially explosive materials 
• Demolition of 11 buildings (5 acres) 
• Cleaning and demolition of 156 aboveground storage tanks with volumes up to 500,000 gallons

Phase II 

• Characterization and stabilization of waste contained in 7,500 drums 
• Treatment of 20,000 cy of sediments and Principal Threat Soils exceeding PRGs

Phase III 

• Installation of RCRA Type C cap over a 3-acre pond containing arsenic scrubber sludge 
• Treatment of 16 million gallons of low ph (<2) liquids impacted with metals 
• Treatment of 70,000 cy of underlying sediments in a 4-acre pond 
• Demolition of 250-foot-tall concrete stack

Phase IV (December 2002 – May 2003) 

• Installation of a 55-foot deep, 3,000-foot-long slurry wall 
• Management of 50,000 cy of hazardous and non-hazardous slag 

Phase V (April 2003 – October 2003) 

• Construction of an on-site landfill for disposal of waste and installation of RCRA Type C equivalent cap 
• Pumping, sediment treatment and capping of four wastewater ponds encompassing 25 acres 
• Installation of an evapotranspiration system and monitoring system 
• Consolidate 20,000 cy of NORM, construction and RCRA capping of NORM landfill

Verdantas is currently managing the O&M and coordinating a team of experts conducting a Focused Feasibility Study to address radiological impacts to groundwater from historic operations. The team has updated the Conceptual Site Model and is currently evaluating Monitored Natural Attenuation of radionuclides in groundwater as a remedy component, along with other alternatives.

Post-remedy, EPA issued the nation’s first Ready for Reuse (RfR) determination for the site in 2003. In 2014 an energy company proposed redevelopment of the Site for use as a petroleum product terminal to receive, store, and deliver crude oil via pipeline to Houston area refineries and waterborne markets. During 2015 and 2016, on behalf of the PRPs, Verdantas worked closely with the energy company, land owner and EPA to ensure compliance with the Site IC standards and to Protect the Remedy. The highly successful redevelopment project was selected by EPA as a Case Study in its Superfund Redevelopment Initiative Series. In 2017, the EPA presented Verdantas (PNL), the Tex Tin PRP group and the energy company an Excellence in Site Reuse Award. “The Tex Tin site shows the benefits of stakeholders working together to make the most of formerly contaminated sites,” said Acting Regional Administrator Samuel Coleman. “Because of the efforts of these different groups, the site is now an active part of the Texas City economy.” 

Key Take-aways 

• 140-Acre Superfund Site 
• Project Coordination 
• Construction Oversight 
• Superfund Success Story 
• Regulatory Management and Advocacy 
• Ongoing O&M and FFS 
• Site Redevelopment and Reuse 
• Monitored Natural Attenuation