Project:
Former Rotogravure Printing Facility
Bottom Line: Successfully used In Situ Chemical Reduction to Treat the Downgradient Portion of a Soluble Cadmium Plume and Reduce the Potential for Recontamination of Wetland and Riverbed.
Summary of Project
The site formerly contained a rotogravure printing facility that operated from the 1960’s to 1980. Cadmium-impacted surficial soil and groundwater have impacted a downgradient wetland and riverbed through erosion and groundwater discharge. Phased remediation is required to remove cadmium-impacted wetland hydric soil and river sediments, while reducing the potential for recontamination by cadmium-impacted soil and groundwater.
- Participated in a feasibility study with a team of experts to identify technologies for groundwater remediation. Conducted a bench-scale soil column study to evaluate the effectiveness of aquifer flushing for achieving remedial objectives. Evaluated technologies and selected in situ chemical reduction via polysulfide precipitation.
- Conducted multiple bench-scale treatability studies to evaluate polysulfide reagents and optimal dosage, long-term stability of precipitated minerals, and potential secondary amendments to enhance the efficacy of polysulfide treatment. Designed and conducted a field-scale pilot test to evaluate the effectiveness of calcium polysulfide (CPS) for treating soluble cadmium impacts.
- Prepared specifications for soil excavation and full-scale CPS injection as part of client’s competitive bidding process. Assisted client with contractor selection by evaluating technical component of bid responses. Acted as client representative during remedy implementation including reviewing submittals for consistency with project specifications and monitoring for deviations from baseline scope of work, schedule, and project budget.
- Designed and implemented a second CPS injection program to treat the downgradient portion of the soluble cadmium plume totaling approximately 28,600-square-feet. Provided field oversight during injection including collection of geochemical field parameters and groundwater samples for expedited laboratory analysis. Monitored key performance indicators including average daily injection productivity throughout the program to manage potential risks to the project baseline. Optimized active injection activities by installing supplemental injection points near compliance wells with limited or no geochemical response to injections.
- Coordinated with third-party specialist for preparation of wetland and riverbank restoration plan in support of future excavation of cadmium-impacted hydric soil and river sediments.