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AITACHMENTB George Veni & Associates 11304 Candle Park, San Antonio, Texas 78249-4421, 210-558-4403, gveni@f1ash.net SCOPE OF WORK AND RESPONSIBILITIES FOR PROJECT CONSULTANT Phase 1 Karst Hydrogeological Assessment of Proposed Extension of Wonder World Drive to RM 12, Hays County, Texas I. Project Description The City of San Marcos is proposing construction of an extension of Wonder W orId Drive to connect with R.M: 12. The road extension will be located near the western boundary of the city in Hays County, Texas. The extension, including probable connectors, will be about 4.8 km long. Except for the southernmost 450 m, the extension is located entirely on the recharge zone of the Edwards (Balcones Fault Zone) Aquifer. The recharge zone is an environmentally sensitive area that is critical to the maintenance of the San Marcos water supply and economy. Additionally, the aquifer is critically imponant to the survival of four plant and animal species at the San Marcos Springs that are federally listed as endangered, plus the Texas Blind Salamander (Typhlomolge rathbttm), which lives in that ponion of the Edwards Aquifer Two localities of the Texas Blind Salamander occur in the immediate area of the proposed road: Johnson's Well and Primer Well (Longley, 1978). A third locality, Ezell's Cave, occurs about 500 m to the east and its waters have been dye traced to the San Marcos Springs (Ogden et al. 1986). While most recent concerns about the, endangered species have been related to the quantity of springflow, the U.S. Fish and Wildlife Service (1996) has expressed considerable concern about the impacts of water quality on the species. Their species recovery plan discussed potential impacts for non-point source pollutants, such as urban runoff, and cited that the Edwards Aquifer area in Bexar, Comal, and Hays counties has the greatest number of central Texas oil and chemical spills that affect surface and groundwater, with potential for catastrophic spills occurring on roadways; of the three counties, Hays has the lowest number of incidents. The plan funher addresses the need to protect aquifer and springflow water quality for the well being of the species. The purpose of this investigation will be to perform a Phase 1 hydrogeologic assessment of the proposed road alignment (roughly 500 acres) to locate any caves, karst features, or geologic features. This information will be assessed and presented to Hicks and Company to assist the City of San Marcos in determining the feasibility of road in that location, and minimizing its impact on the aquifer and endangered species should it be built. PAGE 13 OF 15 OF EXHIBIT 1