The Mexican government is planning additional testing in areas impacted by a major 2014 mining disaster in neighboring Sonora.

The effort is a part of the larger Justice for Cananea program, which seeks to address a number of long-standing issues in the mining community and surrounding areas.

María Luisa Albores, environment and natural resources secretary, said that testing of water, soil and air will be done in collaboration with communities impacted by the 2014 Buenavista copper mine spill, which sent millions of gallons of copper sulfate acid solution down two important rivers.

Some residents have questioned the need for additional testing, and simply want action to ensure clean water. Grupo México, the owner of the mine, has previously said the cleanup was completed within several months of the spill, which it has also said is not responsible for elevated levels of some heavy metals found in Rio Sonora Valley well samples.