Overcoating of Lead-Based Paint on Steel Structures

摘要

Hazardous lead-based paint (LBP) has been used extensively on all types of Department of Defense steel structures and steel components. The removal of LBP is generally performed by abrasive blasting or by water jetting. Containment and disposal of surface preparation debris, worker protection, and other regulatory compliance costs combine to make removal of LBP very expensive. The Environmental Security Technology Certification Program (ESTCP) project reported here demonstrated the overcoating process, which may be defined as the practice of painting over existing coatings as a means of extending service life. Overcoating offers the benefit of maximizing the economic life of existing LBP coatings while minimizing present expenditures and reducing worker exposure and hazardous waste generation. Demonstration of the overcoat process was performed on a water tank at Fort Campbell, KY and a railroad bridge at Holston Army Ammunition Plant (HAAP), Kingsport, TN. The installed cost of overcoating on the simple structure (water tank) was estimated at $1.55/sq ft. The installed cost for overcoating on the complex structure (railroad bridge) was estimated at $2.83/sq ft. By comparison, the cost of deleading and installing a new paint system is $5 to $l8/sq ft with an average cost of $8/sq ft.