"This CD-ROM contains a 30 page report with 22 page appendix, and seven maps at 1:15,000 to 1:30,000 scale in easily readable PDF format that address ground-water quality in Castle Valley's valley-fill aquifer and provide recommendations for septic tank soil-absorption-system density based on potential water-quality degradation associated with use of these systems. The maps are described in detail in the report and show geology, valley-fill thickness, total-dissolved-solids concentration, nitrate concentration, ground-water quality class, potential containment sources, and recommended lot size."--Sticker on back of case. 22 pages + 30-page appendices, 7 plates