his handbook was developed by the 
Tri-Service Environmental Risk Assessment Work Group (TSERAWG) 
to serve as a resource for remedial project managers (RPMs) who 
may need to investigate the vapor intrusion pathway at 
Department of Defense (DoD) sites. The Tri-Services of the DoD 
include the Departments of the Air Force, Army, and Navy, with 
the Department of the Navy (DON) including both the Navy and the 
Marine Corps. This handbook was developed to support RPMs 
working on both active and closed Air Force, Army, Navy, and 
Marine Corps bases, as well as Formerly Used Defense Sites 
(FUDS). The handbook is intended to provide a general framework 
for conducting vapor intrusion investigations under the Defense 
Environmental Restoration Program (DERP). Both residential and 
occupational exposure scenarios are discussed since both groups 
can be affected by vapor intrusion