Disclosed are dispensers for volatile materials. There is a container in the form of a well having an internal cavity, a volatile chemical positioned in the cavity, and a multi-layer covering enclosing the cavity. The covering has a lower section that is gas permeable, and an upper section removably bound to the lower section that is not. Embodiments include when (a) the lower section has a top layer that is a blend of high density polyethylene and low density polyethylene; the upper section has a bottom layer that has a mixture of polypropylene and a propylene/ethylene copolymer; and/or the lower section has an upper layer that has low density polyethylene but the lower section does not contain ultra low density polyethylene. These features help prevent premature leakage at the bond between the upper section and lower section.