This report evaluates the potential exposure pathways associated with vermiculite concentrate processing activities at the Ari-Zonolite facility. The site is located in the near downtown area of Glendale, approximately ½ mile from the city hall, downtown shops, and other buildings. The former Ari-Zonolite facility received vermiculite from the Libby, Montana, mine. From 1951 to 1964, the site was leased the site to the Ari-Zonolite Company. Following the removal of the vermiculite concentrate processing equipment in 1964, several businesses have occupied the site. None of these businesses were involved in vermiculite processing activities. The last occupant of the former vermiculite processing building was an automotive restoration business, which vacated the site in 2002.

The W.R. Grace facility in Phoenix, Arizona, received vermiculite concentrate from the Libby, Montana, vermiculite mine. W.R. Grace Company has owned and operated the Arizona site since 1964. In 1964 W.R. Grace purchased the company that had previously occupied the site and, following the relocation of its vermiculite exfoliation furnace from Glendale, Arizona, began processing vermiculite concentrate and marketing it under the Zonolite® brand. The objective of this health consultation is to evaluate exposure pathways and potential health effects in those persons who, between 1964 and 2002, may have been exposed to Libby asbestos as a result of vermiculite concentrate processing activities and waste materials from the W.R. Grace exfoliation facility in Phoenix.