The salvage industry is involved with selling reusable parts, materials, fluids and coolants, etc. In the case of automobile salvage businesses, these parts and other materials are from used and damaged vehicles. Consumable materials and reusable fluids, such as gasoline and brake fluid that are not resold are either used on site, or they are removed from the facility by a licensed waste hauler. Metal scrap that is not sold as parts is sent to a metal reclaiming facility, and plastic that is not sold is sent to a landfill or plastic manufacturing facility where the material is ground and recycled into other plastic commodities.

Depending on the type of salvage facility, operations may include vehicle disassembly, draining fluids from vehicles, crushing, and in some cases shredding, vehicles. Miscellaneous materials such as auto bodies, parts, drained fluids, batteries, etc. are stored on site until they are sold, disposed of, or reused.

Environmental contamination can occur at many stages of the salvage yard operations. Soil, groundwater and air can be contaminated during vehicle disassembly and fluid drainage operations. Contamination can also result from improper handling and storage of materials (batteries, captured refrigerants, fluids, etc).

Commonly, disassembly of machinery, equipment or vehicles is conducted outside. Parts are removed for resale and the carcass of the vehicle is then crushed and shredded to reclaim the metal.

The main environmental concern in vehicle crushing and shredding operations is letting any fluids still in the vehicle get out of control and enter the environment by spilling on the ground or evaporating into the air. Spills that occur on paved surfaces (concrete or asphalt) should be cleaned up immediately. Although not readily apparent, both of these surfaces are permeable. If fluids are not cleaned up, over time they will soak through the asphalt or concrete and contaminate the soil below. These contaminants can then migrate due to stormwater runoff, etc. and contamination and liability will spread far beyond the immediate area of the salvage yard. Preventing these spills by draining fluids, cleaning accidental spills up and carefully managing salvage yard operations will minimize the risks.

In addition to a variety of fluids that may contaminate the environment if spilled or evaporated, automobiles are a source of other hazardous materials, such as mercury, lead, and asbestos. Specific hazards associated with materials found in vehicles will be discussed in the ?Reasons for Change? section of this Topic Hub.

The following are some examples of common operations at a salvage facility that may result in environmental contamination or in the production or collection of potential pollutants:

Power Washing Engine Parts
Commonly engines and other parts are removed from the vehicle and power washed prior to entering them into the inventory system. Power washing activities utilize hot water and degreaser chemicals. Emulsified oils and grease can contaminate the wash water in addition to the degreaser products, which is commonly a caustic (high pH) solution.

Removal of Air Bag Cartridges
Sodium azide is the chemical used in automotive air bags to detonate the capsule in the event of a crash. Sodium azide tablets are packed into metal canisters inside the air bag. On impact, an electromechanical trigger heats the sodium azide, which causes it to explosively decompose, forming nitrogen and metallic sodium. Silica and iron oxide may also be added to the cartridges to facilitate the chemical reaction. (Sodium Azide in Car Airbags Poses a Growing Environmental Hazard, Eric Betterton, University of Arizona, August 2000.)

Removal of Antifreeze
Antifreeze (ethylene glycol or propylene glycol) solution is drained from radiators and engine cooling system including the radiator, water pump, and hoses. Glycols increase the surface tension of water or other fluids and help prevent critical engine cooling fluid from freezing or overheating.

Removal of Brake Fluid
Brake fluid is used to lubricate breaking systems in vehicles. During the process of dismantling a vehicle the brake fluid is drained and collected for recycling.

Removal of Lead-Acid Batteries
Spent lead-acid batteries are removed from vehicles and stockpiled for reuse, sale or recycling. Each of the Great Lakes states require lead-acid batteries to be recycled versus disposed in a landfill.

Removal of Mercury Switches
Switches mounted in vehicles commonly contain mercury. Mercury is used in switches mounted on vehicles to turn on the hood, trunk or door lights when they are opened, and/or to operate some anti-lock brake systems (ABS Systems).

Removal of Oil and Oil Filters
Oil is drained from the crankcase of engines. Oil filters are removed from the engine.

Removal of Power Steering Fluid
Power steering fluid is drained from the power steering lines and the power steering pump.

Removal of Transmission Fluid
Transmission fluid, used to lubricate automobile transmissions, is mainly composed of mineral oil. The fluid is drained from the transmission upon removal from the vehicle. Transmission fluid is flammable at high temperatures and relatively non-toxic unless swallowed or aspirated into the lungs.

Removal of Windshield Wiper Solution
Windshield wiper solution is removed from the reservoir in the engine compartment.

Tire Removal and Storage
Tires with little wear are commonly collected and sold. Severely worn tires are commonly stored outside in piles prior to disposal. Tires stored outside exhibit a health hazard because they can create a breading ground for disease carrying mosquitoes. Tire piles are also a fire hazard; once a tire fire starts, it is difficult to control.