Longevity Estimates for a Permeable Reactive Barrier System Remediating a 90Sr Plume

A permeable reactive barrier system, known as the Wall and Curtain, was installed at the Chalk River Laboratories, Chalk River, Ontario, in 1998, to intercept a 90Sr plume. The system employs clinoptilolite, a zeolite, as a reactive material which adsorbs 90Sr. Reactive transport simulations of the site were conducted using the numerical code HydroGeoSphere to provide longevity estimates for the system. The HydroGeoSphere simulations included three solutes, for which zoned distribution coefficients were specified. Longevity estimates derived from the simulation were between 70 and 100 years for the Wall and Curtain system.