Diverse situational factors (such as hydrogeological formations and ag
ricultural cropping practices) and the lack of a clear federal mandate
present a new challenge to the Environmental Protection Agency and st
ate governments in implementing groundwater protection policy. An impl
ementation regime framework is presented that calls on state and feder
al administrators to negotiate an informal working relationship that i
s appropriate for each state. This might include either the traditiona
l implementation of a uniform federal mandate or a program tailored to
specific state needs. The success of an implementation regime in achi
eving its policy objectives is based on the ability of the federal gov
ernment to frame a clear and consistent message that will reduce state
implementers' concerns over federal government intrusion. A regime ty
pology is presented depicting ideal regime types that may be used by t
he federal government in selecting an appropriate federal message.