Concrete Disposal Dangers

When concrete structures are renovated or demolished, the concrete is often recycled. Left over concrete was once trucked to landfills for disposal, but recycling has become an attractive option for those with greater environmental awareness. Concrete aggregate that is collected and disposed of from demolition sites may be put through a crushing machine to make disposal more efficient. Crushing facilities accept only concrete that is free of debris and other hazardous materials. Builders have become savvy in the disposal of concrete in order to reduce the negative impact to the environment.

Storm Drains

• Concrete waste should not be poured down storm drains. The concrete waste kills fish because the concrete can clog the fish's gills and cause asphyxiation. Instead of pouring leftover concrete down the drain, locate the washout area that is usually around 50 feet from the storm drain or open ditch. You can prevent runoff from the washout area by creating a temporary lined pit. Wash the waste into the pit and allow the concrete to set. After the concrete sets, break it up and take it to a concrete recycling location in your area.

Concrete Crushing

• If possible, you should crush the concrete at the actual construction site. Portable crushers reduce the pollution generated when compared to transporting the construction waste material to a quarry. Large road-portable plants can crush asphalt rubble and concrete at 600 tons per hour. You can also use a self-contained mini crusher that crushes at only 150 tons per hour but that can fit into smaller areas and is suitable for smaller projects. If concrete is crushed, the windblown dust carrying lead and other debris could cause additional risks to the environment.

Lead Paint Contamination

• Recycling painted concrete can be hazardous due to possible lead content. According to the Army Corps of Engineers, lead-based paint in concrete poses an environmental risk. Paint from concrete can chip and lead can leak from the paint over time where the painted concrete has been disposed. As a result, the lead could leak into the groundwater or end up in the surface water due to soil erosion. It is possible to test the lead content in the concrete on your own with a lead testing kit. If there is significant lead present, you will need to truck the concrete to a disposal site.

Alkali-Silica Reaction

• The chloride content of concrete aggregate should be a concern if the material will be used as reinforced concrete. Chloride content can be a problem if the concrete you are using comes from pavements in northern climates. In these climates, the road salt is freely spread in the water and the alkali content is often mixed with unsuitable materials. When this concrete is disposed of or even recycled, there is a risk of an alkali-silica reaction. Alkali-silica reaction can result in expansion and cracking in the concrete.