AWP Holdings Limited operates a solvent wool scouring plant at Miguel Road, Spearwood, Western Australia. One of its wastes is mud resulting from agricultural dirt scoured from the wool. The composition of the mud is grit, organic matter, salt with traces of heavy metals and pesticides, particularly the insecticide diazinon.

The proposal is to carry out a year's trial on disposing of the mud by injecting it into the subsoil on land at Amarillo Farm. The property straddles the lower reaches of the Serpentine River north of Mandurah and is in the catchment of the eutrophic Peel-Harvey catchment.