The 1997 DLM study states that phosphates derived from raffinate (which contains phosphoric acid) have too high a metallic content and that it should be established what an acceptable proportion would be.
DLM-uuringus rajatise teostatavusest novembrist 1997 öeldakse, et (fosforhappesisaldavusega) rafinaadist saadud fosfaadi metallisisaldus on liiga kõrge ning et tuleks kindlaks teha, missugune oleks aktsepteeritav metalli osakaal.