Solidification/Stabilization (S/S) with cement is a common method for the safe treatment, management and reuse of contaminated waste. Developed in the 1950s, the technology is widely used today to treat industrial hazardous waste and contaminated sites. S/S is being chosen for use on key sites in Canada, contributing to the sustainable redevelopment of both urban and industrial properties.
S/S, which involves mixing portland cement into contaminated material, protects human health and the environment by immobilizing hazardous constituents within the treated material. The cement reacts chemically with water in the material being treated, creating changes in the physical and chemical properties of the treated materials preventing the escape of hazardous constituents into the environment. Solidification refers to changes in the physical properties of the waste, including an increase in its compressive strength that enables it to support more weight, a decrease in its permeability that reduces water infiltration, and encapsulation of hazardous constituents. Stabilization refers to chemical changes in the hazardous constituents in the waste, that convert them into a less soluble, mobile or toxic form.
The popularity of S/S is due to the fact that it can be used for a wide variety of contaminants in many types of contaminated material. Soil, sediment and sludge impacted with an array of organic and inorganic contaminants have been treated successfully using this versatile technology. There are two distinct methods for the treatment of contaminated material. Cement may be mixed directly into hazardous material on-site or it may be excavated and transported off-site for treatment. Afterwards, the treated material may be safely reused on-site or disposed in a landfill.
S/S provides an economically viable means of treating contaminated sites. Because this technology can treat and contain contaminated soil on site, it often reduces the need for landfill disposal. It protects surrounding communities and water resources by preventing leaching of contaminants into groundwater.
S/S with portland cement has benefits that make it more economical and easier to use than other methods:
- Cement is manufactured under strict CSA and ASTM Standards, ensuring uniformity of quality and performance
- Cement’s success in S/S is supported by more than 50 years of use in a variety of projects
- Cement has a long-term performance record
- Cement usage can minimize volume increase compared with other reagents
- Cement is a non-proprietary manufactured product, readily available across the country in bag or bulk quantities
A set of complementary concrete pavement resources are highlighted in the links below:
Useful websites and resources
- Solidification and Stabilization of Wastes Using Portland Cement
- Solidification / Stabilization of Contaminated Soils
- Applying Solidification / Stabilization Treatment to Brownfield Projects
- Remediation of Lead and Petroleum – Contaminated Soils at A Boston Brownfield Site Using Cement-Based Solidification and Stabilization
- Solidification/Stabilization Treatment of Arsenic- and Creosote-Impacted Soil at a Former Wood-Treating Site
- New Bedford Harbor Superfund Site Area D Bulkhead Project
- In-Situ Solidification / Stabilization of a Former Wood Treatment Site
- Phoenix-Award Winning Kendall Square Rises from Cement-Treated Brownfield Site
- Solidification/Stabilization Treatment at the Brunswick Wood Preserving Superfund Site
- A Citizen’s Guide to Solidification and Stabilization
- Guide to Improving the Effectiveness of Cement-Based Stabilization / Solidification
- Solidification / Stabilization for Remediation of Wood Preserving Sites: Treatment for Dioxins, PCP, Creosote, and Metals
- Stabilization / Solidification Processes for Mixed Waste
- Solidification/Stabilization Treatment at a Former Manufactured Gas Plant Site
- Augusta Manufactured Gas Plant Cleanup Using Cement-based Solidification/Stabilization
- Solidification/Stabilization Treatment of Dredged Material from the Port of San Diego
- S/S Treatment of Dioxin Soils at Naval Construction Battalion Center Gulfport
- CQA Methodologies for In-Situ S/S at Former Manufactured Gas Plants
- Remediation of Hercules 009 Landfill
- Stabilization / Solidification (S/S)