These different categories of mineral waste are
not systematically measured and estimates are not available for all mineral
waste categories. For example, blasting done in road construction projects
results in "waste" that is similar to the waste rock from mining,
yet it generally does not get counted since it is typically crushed up and
used as fill. Waste rock resulting from mining often does not have an application
of this kind close by and therefore gets counted as waste rock.
Waste rock is mined material that has not been processed to recover valuable
materials and typically carries little or no risk to health or the environment.
Tailings are a residual following the processing of materials and are subject
to ongoing management regimes.
This estimate does not cover waste
managed on-site by companies or households (for example, backyard composting)
or materials that are transported directly to secondary processors. See textbox
"Waste Management Industry Survey: Coverage" in Section 3 for