In situ formation of phosphate barriers in soil

United States Patent

July 9, 2002
View the Complete Patent at the US Patent & Trademark Office
Hydroxyapatite Barriers for Radionuclide Containment
Reactive barriers and methods for making reactive barriers in situ in soil for sequestering soil ontaminants including actinides and heavy metals. The barrier includes phosphate, and techniques are disclosed for forming specifically apatite barriers. The method includes injecting dilute reagents into soil in proximity to a contamination plume or source such as a waste drum to achieve complete or partial encapsulation of the waste. Controlled temperature and pH facilitates rapid formation of apatite, for example, where dilute aqueous calcium chloride and dilute aqueous sodium phosphate are the selected reagents. Mixing of reagents to form precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.
Moore; Robert C. (Edgewood, NM)
Sandia Corporation (Albuquerque, NM)
March 1, 2000
405/129.45 ; 405/263; 588/249;
B09B 1/00 (20060101); B09C 1/00 (20060101); B09C 1/08 (20060101); E02D 003/12 (); B09B 001/00 ();
405/128.1,128.7,129.45,129.6,129.65,129.25,263,270 588/249,250
This invention was made with support from the United States Government under Contract DE-AC04-96AL85000 awarded by the U.S. Department of Energy. The Government has certain rights in this invention.