This report provides a user's manual for Version 1.2 of the Advanced Scavenging Module (ASM). It is an interim code and is intended primarily for coordinating development of the module with that of the evolving NCAR Regional Acid Deposition Model (RADM). The ASM is currently in an evolutionary stage; the general framework provided by Version 1.2 is sufficiently well-established to provide the basis for future versions. The code supplied with this manual is a complete, operational system, and was tested. The ASM is activated by two types of subroutine calls from the host code. Upon advancing to some ground-level position (x,y) on the host's numerical computation grid, the ASM is interrogated (using the first subroutine call) to produce the vertical distributions of storm features above that point. Following this, scavenging computations are performed repeatedly for each vertical grid position, using the second subroutine call. The primary outputs from these secondary ASM interrogations are the transformation rates associated with the physical and chemical components of the scavenging process. These rates are returned to the host code and incorporated with its normal numerical integration procedure.