Two-stage remediation of particulate material

A two-stage process for treating particulate materials containing organic contaminants comprising:

• removing an amount of contaminated particulate material from its location;
• transferring the contaminated particulate material to a thermal desorption unit;
• subjecting the contaminated particulate material to a thermal desorption process, wherein the thermal desorption process includes heating the contaminated particulate material to volatilize a portion of the organic contaminants and to form a preheated contaminated particulate material, and collecting the volatilized organic contaminants outside of the thermal desorption unit;
• transferring the preheated contaminated particulate material to a smoldering combustion unit;
• and
• subjecting the preheated contaminated particulate material to a smoldering combustion process, wherein the smoldering combustion process includes admitting the preheated contaminated particulate material to a smoldering combustion unit having an inlet for a contaminated particulate material and an outlet for a treated particulate material to be withdrawn from the unit, operating the smoldering combustion unit under conditions sufficient to ignite a smoldering combustion reaction, which creates gaseous combustion products, collecting the gaseous combustion products outside of the smoldering combustion unit, and withdrawing a treated particulate material from the outlet of the smoldering combustion unit.