An improved Jet-Plume model has been interfaced with DEGADIS to provide for prediction of the trajectory and dilution of elevated dense gas jets to ground contact. DEGADIS predicts the ensuing ground-level plume dispersion. The Jet-Plume model provides for: automatic adjustment of integration step-size (using the Runge-Kutta-Gill method as in DEGADIS): elliptical plume shape (cross-section), with the Pasquill-Gifford plume dispersion coefficient representation of atmospheric turbulent entrainment; user specification of averaging time; ground reflection when the plume (lower) boundary reaches ground level; and application to scenarios where the plume remains aloft. The model should be uploaded via modem from a PC terminal to host a VAX computer, and several files must then be renamed prior to compilation and execution. The program is written in FORTRAN for compilation and execution on a DEC VAX Computer.