Section 1: Land Disposal

Trends in Land Disposal

Since 2010, large fluctuations in releases have been driven by changes in on-site land disposal. This figure shows on-site land disposal over time in more detail. From 2003 to 2013, on-site land disposal has increased from 2.42 to 2.75 billion pounds, a 28% increase. Recent fluctuations are primarily due to changes in waste quantities reported to TRI as “other land disposal,” which can include chemical waste disposed of in waste piles and spills or leaks. From 2003 to 2013, “other land disposal” increased by 131%, while all other types of on-site land disposal decreased. Most of the toxic chemical waste reported as other land disposal is contained in waste rock at metal mines. Metal mines accounted for 518 million of the 525 million pound increase in land disposal from 2012 to 2013. For this reason, the next figure presents on-site land disposal excluding metal mining.

Metal mining facilities typically handle large volumes of material. In this sector, even a small change in the chemical composition of the deposit being mined can lead to big changes in the amount of toxic chemicals reported nationally. In recent years mines have cited changes in production of waste rock, changes in the composition of waste rock, and the closure of a heap leach pad as the primary reasons for the reported variability in land disposal of TRI chemicals. Changes in waste rock composition can have an especially pronounced effect on TRI reporting because of a regulatory exemption that applies based on a chemical’s concentration in the rock, regardless of total chemical quantities generated.

Federal and state agencies require that waste rock be placed in engineered structures that contain contaminants. Federal and state land management agencies also require that waste rock and tailings piles and heap leach pads be stabilized and re-vegetated to provide for productive post-mining land use.

For more information on waste management by the mining industry, see the Metal Mining section.

This figure shows that total on-site land disposal for all industries other than metal mining has decreased from 2003 to 2013 by 12%. Disposal to landfills, which accounts for the greatest percentage of land disposal, decreased by 14% over this time period.

While releases to land have decreased in other sectors, releases by metal mining drive overall land disposal trends. See the following section, land disposal by industry, for more information.

This page was published in January 2015 and uses the 2013 TRI National Analysis dataset made public in TRI Explorer in October 2014.