Air monitoring was performed at a hazardous waste remedial action site to measure inhalation exposure at the drum bulking unit processes and ambient emissions downwind from that process. Contaminant concentrations were all well below permissible exposure limits. This study suggests that when workers remain in fixed job locations at hazardous waste sites, occupational inhalation exposure monitoring must consider contaminants generated upwind of the job location as well as contaminants generated at the specific job site. Air sampling must also consider both the particulate and vapor phases of the site contaminants.