The low levels of Si and A1 found in leachate 3 indicate that only slight attack of the major silicate components occurs during treatment with NH20H.HCl-HOAc. A relative de- crease of the smectites X-ray diffraction peak is noted, suggesting partial attack of these minerals. Contrary to the results of Chester and Hughes, however, no evidence of chlorite transformation can be observed from X-ray diffraction analysis.