Lead and Titanium Dioxide Contamination Remediation

The project involved remediating a legacy industrial site contaminated with lead and titanium, focusing on both in-situ stabilization (ISS) and ex-situ stabilization (ESS) of approximately 97,000 cubic yards of titanium sludge across two areas of a former titanium ore processing facility. Significant challenges included managing the contaminated water and sludge, handling wet conditions that necessitated specialized equipment, and ensuring effective treatment and disposal of PCB-impacted materials.

We implemented a multifaceted approach to address the site’s complexities. Initially, we created an on-site reservoir with a 15-million-gallon capacity to store contaminated liquid from the dewatering of the impoundment work zone, allowing the segregation of clean water for discharge.

To remove the PCB-impacted sludge from the impoundment, we strategically installed bridging roads within the impoundment to facilitate access for excavators maneuvering on crane mats and deployed an amphibious excavator to safely navigate the wet terrain. We used ex-situ stabilization (ESS) to process the PCB-impacted sludge removed from the impoundment, optimizing efficiency and safety.

For ISS of the non-PCB-impacted sludge within the impoundment, we prepared treatment cells measuring 4 feet deep, 20 feet wide, and 200 feet long to ensure controlled stabilization. We pneumatically applied Portland cement to the surface of each cell, followed by a dual mixing method: initial raking for cement distribution and traditional bucket mixing for thorough homogenization.

We systematically progressed from the site edges inward, stabilizing each area in sequence. After curing periods of 1-2 days, treated materials attained sufficient strength for subsequent cell mixing. Upon completing sludge stabilization, we reconstructed the west reservoir berm, enhancing site integrity post-remediation.

Our meticulous execution was pivotal in preparing these areas for future redevelopment. By effectively managing and treating contaminated materials, including complex PCB-impacted sludge, we achieved significant environmental remediation milestones. The implementation of ISS in controlled treatment cells ensured thorough stabilization, minimizing environmental risks and enhancing site safety.

The reconstructed reservoir berm bolstered infrastructure resilience, marking a critical step toward sustainable land use and safeguarding community and environmental health. This comprehensive remediation effort underscored our commitment to environmental stewardship and our capability in effectively managing complex hazardous waste challenges.