In Situ Access to Contaminants

working with a purple haze

Diffusive transport of reagent to contaminant
Slightly soluble reagents (e.g. KMnO4) dissolve at the fracture and distribute into the surrounding matrix via diffusion. Any local fluid flow will further enhance distribution by convective and dispersive processes.

2nd Order Passive In Situ Transport of Reagent to Contaminant

Hydraulic fractures created with slightly soluble reactive materials act as long-term sources of reagent within the target formation.  The reagent material dissolves at and within the fracture and then distributes into the surrounding matrix via diffusion.  In this fashion, an ever-expanding halo of reactive material forms around the fracture, degrading any contaminant within it.  The halo grows until the proppant in the fracture is exhausted, which may require most of a decade.  In the case of potassium permanganate, the resulting halo can be many feet thick.  Any local groundwater flux will further distribute the dissolved reagent by convective and dispersive mechanisms.