INTRODUCTION

Selected Papers in the Hydrologic Sciences, a U.S. Geological Survey-managed journal-type publication in the Water-Supply Paper series, is aimed at meeting widespread public and professional needs for results of state-of-the-art broad-based hydrologic studies. The results of these studies are derived from integrated water-resource projects of the Federal research program, Federal-State cooperative program, and, to some extent, work done on behalf of other Federal agencies.

This is the sixth issue of the series and consists of 18 topical papers that address a broad array of topics, including ground- and surface-water hydrology, hydrogeochemis-try, land use, and selected hydrologic, geologic, and climatologic techniques for Water-Resources studies.

Selected Papers is intended to serve as a forum that encourages dialog between readers and authors. Participation in such dialog among hydroscientists within and outside the Federal sector would be beneficial. Discussion papers by all members of the hydroscience community are desired. A discussion section for readers' comments and authors' replies will be included in each issue. Such discussion papers for this issue will be open until December 1994,

Posted May 2010