DO NOT use sawdust or other fine cellulose materials to absorb hardeners.
DO NOT dispose of hardener in trash containing sawdust or other fine cellulose materials - spontaneous combustion can occur.
Clean resin or mixed epoxy residue with lacquer thinner, acetone or alcohol. Follow all safety warnings on solvent containers. Clean hardener residue with warm soapy water.
Dispose of resin, hardener and empty containers safely. Puncture a corner of the container and drain residue into the appropriate new container of resin or hardener.
DO NOT dispose of resin or hardener in a liquid state. Waste resin and hardener can be mixed and cured ( in small quantities) to a non-hazardous inert solid.
WARNING: Large pots of curing epoxy can get hot enough to ignite surrounding combustible materials and give off hazardous fumes. Place pots of mixed epoxy in a safe and ventilated area, away from workers and combustible materials. Dispose of the solid mass only if cure is complete and the mass has cooled. Follow federal, state or local disposal regulations.
Removing uncured epoxy. Uncured epoxy is removed as you would spilled resin. Scrape as much material as you can from the surface using a stiff metal or plastic scraper - warm the epoxy to lower its viscosity. Clean the residue with lacquer thinner, acetone, or alcohol. (Follow safety warnings on solvents, and provide adequate ventilation.) Allow solvents to dry before recoating. After recoating wood surfaces with epoxy, it's a good idea to brush the wet epoxy (in the direction of the grain) with a wire brush to improve adhesion.
Removing fibreglass cloth applied with epoxy. Use a heat gun to heat and soften the epoxy. Start in a small area near a corner or edge. Apply heat until you can slip a putty knife or chisel under the cloth (about 121oC). Grab the edge with a pair of pliers and slowly pull up on the cloth while heating just ahead of the separation. On large areas, use a utility knife to score the glass and remove in narrower strips. Resulting surface texture may be coated or remaining epoxy may be removed as follows.
Removing cured epoxy coating. Use a heat gun to soften the epoxy (about 121oC). Heat a small area and use a paint or cabinet scraper to remove the bulk of the coating. Sand the surface to remove the remaining material. Provide ventilation when heating epoxy.