The combination of: an underground valve for a supply line and having an underground actuator through which a state of the valve can be changed to control flow within the supply line; and a conduit assembly embedded in ground material and defining an access passage through which above ground access can be obtained to the valve actuator. The conduit assembly has an adaptor assembly with a body made from a non-metal material and having at least a first connector. The valve has at least a second connector. The first and second connectors cooperate to maintain the body operatively connected to the valve. A first conduit part is configured to connect to the body and bound a portion of the access passage accessible through an entry opening remote from the valve.