PHYSICAL DEMANDS: Consistent mental alertness and dexterity of fingers and both arms and hands to ensure safety and successful completion of essential functions; standing, walking, or sitting for extended periods of time; lifting and carrying light to moderately-heavy objects, occasionally more than 50 pounds; pushing and pulling exerting force to approximately 50 pounds, occasionally 50+ pounds; handling small to large-sized materials, equipment or items; climbing up and down ladders; bending and twisting at waist and neck; crouching and crawling; kneeling and bending at the waist; reaching overhead, above the shoulders and horizontally; using hand and power tools; repetitive use of upper extremities; seeing to read, write, and to complete projects; hearing and speaking to exchange information in person or on the telephone. ENVIRONMENT: Outdoor environment; driving a District vehicle to conduct work; seasonal heat and cold or adverse weather conditions; working around and with machinery having moving parts; exposure to hazardous chemicals.