Rocky mountain arsenal Denver, Commerce City, and Adams county join forces to obtain federal release of arsenal land for use as rail yard. Post Je 1, 1972 p.4 Army Corps of Engineers awards $359,700 contract to Penner Construction Co. for bulk mail center on arsenal land. Post N 6, 1972 P-31 Report on progress of mustard gas burning. Post Ja 11, 1973 p.47 Pentagon prohibits takeoffs over arsenal. Post My 24, 1973 P-3