Moderately heavy physical activity. Required to stand, walk or sit uncomfortably for extended periods; push, pull or lift medium to heavy weights. Exposure to confined spaces, high voltage equipment, dust, grease, heat, cold, dampness, cuts, scrapes, extremely disagreeable odors, noise, heights (tops of holding tanks, basins, vaults, etc.), unknown levels of pathogenic bacteria, and other environmental aspects which may be considered unfavorable or disagreeable. Significant potential exists for exposure to hazardous chemicals and gases. Employees are to follow prescribed safety and hygienic procedures.