The paper states the results of experimental modeling of arsenic transition conditions into near-surface environmental position. The experiments was conducted the samples, collected from dumps of Schlema-Alberoda deposit. Leaching of arsenides (safflorite, loellingite, nickeline, rammelsbergite) was occurred in acid and neutral water within a month. As a result, new unique data of arsenic capability to leach with forming new phases (annabergite, scorodite, iron hydroxide) is received.