On behalf of VRRSP Consultants, LLC and Central Texas Regional Water Supply Corporation (CTRWSC), SWCA Environmental Consultants (SWCA) conducted cultural resources investigations of the Vista Ridge Regional Water Supply (Vista Ridge) Project in Burleson, Lee, Bastrop, Caldwell, Guadalupe, Comal, and Bexar Counties. The work will involve installation of a 139.45-mile-long, 60-inch-diameter water pipeline from northcentral San Antonio, Bexar County, Texas, to Deanville, Burleson County, Texas. The report details the findings of investigations from June 2015 to December 2015, on the alignment dated December 8, 2015 (December 8th). The Vista Ridge Project is subject to review under Section 106 of the National Historic Preservation Act (54 USC 306108) and its implementing regulations (36 CFR 800), in anticipation of a Nationwide Permit 12 from the U.S. Army Corps of Engineers in accordance with Section 404 of the Clean Water Act. In addition, the work is subject to compliance with the Antiquities Code of Texas under Permit Number 7295, as the Vista Ridge Project will be ultimately owned by a political subdivision of the State of Texas. The cultural resources investigations included a background review and intensive field survey. The background review identified previous investigations, recorded archaeological sites, National Register of Historic Places (NRHP) properties, cemeteries, standing structures, and other known cultural resources within a 0.50-mile radius of the project area. The field investigations conducted from June 2015 through December 2015 assessed all accessible portions of the proposed December 8th alignment as of December 25, 2015. Approximately 101.8 miles of the 139.45-mile alignment has been surveyed. Approximately 24.42 miles were not surveyed based on the results of the background review and extensive disturbances as confirmed by vehicular survey. The remaining 13.23 miles that require survey were either unavailable due to landowner restrictions or part of a newly adopted reroute. SWCA also surveyed additional mileage, which includes rerouted areas that are no longer part of the December 8th alignment. The inventory identified 59 cultural resources, including 52 archaeological sites and seven isolated finds. In addition to newly recorded resources, two previously recorded archaeological sites were revisited, and two cemeteries were documented. Of the 52 newly recorded archaeological sites, seven are recommended for further work or avoidance. Of the two revisited archeological sites, one is recommended for further work or avoidance within the project area. Avoidance is recommended for both documented cemeteries. The resources with undetermined eligibility require additional testing or other avenues of research before SWCA can make a firm recommendation about their eligibility for nomination to the NRHP and designation as State Antiquities Landmarks (SALs). As part of a management strategy, the resources with undetermined eligibility may also be avoided by reroute or boring beneath. The remaining 45 cultural resources are recommended not eligible for inclusion to the NRHP or for designation as SALs and no further cultural resources investigations or avoidance strategies are recommended.

On behalf of Central Texas Regional Water Supply Corporation (CTRWSC) and VRRSP Consultants, LLC, SWCA Environmental Consultants (SWCA) conducted archaeological data recovery excavations at multicomponent site 41GU177 (the Snakeskin Bluff Site) within the proposed alignment of the Vista Ridge Regional Water Supply Project (Vista Ridge) in Guadalupe County, Texas. Investigations were conducted in compliance with Section 106 of the National Historic Preservation Act (NHPA) (54 United States Code [USC] 306108) and its implementing regulations (36 Code of Federal Regulations [CFR] 800), in anticipation of a Nationwide Permit 12 from the U.S. Army Corps of Engineers (USACE) in accordance with Section 404 of the Clean Water Act. In addition, the work is subject to compliance with the Antiquities Code of Texas (ACT), as the Vista Ridge Project will be ultimately owned by CTRWSC, a political subdivision of the State of Texas. The Vista Ridge project will involve construction of an approximately 140-mile-long, 60-inch-diameter water pipeline from north-central San Antonio, Bexar County, to Deanville, Burleson County, Texas. The of area of potential effects (APE) for the Phase I survey efforts included the proposed centerline alignment and a 100-foot-wide corridor (50 feet on either side of centerline), as well as temporary and permanent construction easements, and aboveground facilities, such as pump stations and the northern and southern termini sites. Between June 2015 and March 2018 the cultural resources inventory identified 78 cultural resources (i.e., 64 archaeological sites and 14 isolated finds). Included in that inventory was site 41GU177, originally discovered on August 31, 2015 on the west bank of the Guadalupe River. Site 41GU177 is a stratified prehistoric site on the western high bank of the Guadalupe River southeast of New Braunfels, Texas near the community of McQueeney. The site contains components deposited intermittently from approximately the Late Archaic to Transitional Archaic periods through Late Prehistoric times. The primary components investigated in the excavations span the final Late Archaic period and into the Austin phase of the Late Prehistoric, a timeframe from approximately 2,600 to 900 years ago. The field investigations, conducted between October 2016 and December 2017, included intensive shovel testing, geomorphological study with mechanical excavations, and subsequent hand excavations. This report presents the results of the data recovery investigations conducted from November–December 2017. The survey results and testing results have been previously reported on (Acuña et al. 2016; Rodriguez et al. 2017); the testing results are also presented in Appendix A. SWCA’s work at 41GU177 was conducted under the ACT. The state regulations mandate the evaluation of the site’s eligibility for designation as a State Antiquities Landmark (SAL) or for listing on the National Register of Historic Places (NRHP). The survey and testing investigations were conducted under ACT Permit No. 7295, and the subsequent data recovery was completed under Permit No. 8231. Brandon S.Young served as initial Principal Investigator (PI) on both permits and Christina Nielsen took over asPI on the permits for the final reporting stages of the project. Overall, 34.1 m3 of sediment was excavated from the site during the data recovery through both traditional and feature-focused unit excavations. During these excavations, approximately 22 m2 of Late Prehistoric components were exposed, consisting of rock-lined hearths and 6,496 artifacts. The Late Prehistoric artifacts included Edwards points, Perdiz points, a Fresno point, ceramics, bifaces, an end scraper, a shell bead, various informal lithic tools, ground stone, choppers, debitage, and faunal remains. The Late Prehistoric component was approximately 40–80 cm thick. No cultural features were identified within the underlying Archaic components of the site; however, 3,421 artifacts were recovered including a Zephyr point, bifaces, ground stone, various informal lithic tools, choppers, debitage, and faunal remains. The Transitional Archaic component was approximately 35–60 cm thick; however, the underlying Archaic (and possible older) components were not defined. The excavations were limited to the right-of-way, and consequently the exposure afforded only a partial glimpse of the overall site. Based on the assemblage, the site is interpreted as a logistical base camp as indicated by both formal and informal tool forms and site furniture. Small groups exploited the abundance of lithic raw material and riparian zone resources, making forays into the landscape to hunt and forage. A total of four radiocarbon dates from the Late Prehistoric components reveal several short-term encampments over the course of several centuries from approximately 600 to 1200 B.P. (A.D. 750 to 1350). The Toyah Phase component has some noted disturbances (especially towards the ground surface), but good integrity from where the radiocarbon sample was collected. The Austin Phase component is vertically and horizontally discrete, contains a substantial amount of archaeological materials, and the site structure and radiocarbon dates suggests multiple, discrete occupations. The data recovery investigations at the Snakeskin Bluff site sought to address environmental, technological, chronological, and adaptive changes during the transition from Archaic to Late Prehistoric. As mentioned, the overall artifact and feature recovery at the site was low and disturbances and mixing of components was noted, especially within the upper deposits of the site. Disturbances within the Late Prehistoric Toyah Phase were most prevalent in the eastern portions of the site. The Late Prehistoric Austin Phase component contained intact, well-preserved archaeological deposits containing preserved flora and faunal material, cooking features, and diagnostic implements. The Transitional Archaic (and older) occupations were difficult to characterize, due to limited quantities of temporal diagnostic artifacts, lack of cultural features, and low artifact recovery. Despite these limitations, the data recovered from the cultural components show diachronic shifts between the technological and foraging strategies of the Archaic and Late Prehistoric. In concurrence with the 2016–2017 testing recommendations, the Snakeskin Bluff site is considered eligible for designation as an SAL and for the NRHP. Although not all cultural components of the site were stratigraphically discrete, the Late Prehistoric Austin Phase component revealed intact, well-preserved archaeological deposits that significantly contributed to our understanding of Late Prehistoric patterns. Given the sensitive nature of the cultural deposits at 41GU177, the main concern following the completion of data recovery excavations was the prevention of significant surface and subsurface impacts to the site during clearing and pipeline construction. As such, SWCA developed a site monitoring protocol; methods and results of the monitoring efforts are provided in Appendix H. Contributing components beyond the impact area will not be affected and will be preserved by avoidance; however, it is important to note that these investigations mitigated the project-specific effects, not the entire site. Any future project that could impact the site’s deeper deposits, or those beyond the current right-of-way, warrant further consideration to assess the possibilities for additional contributing components. With these considerations, no further work is recommended.

On behalf of VRRSP Consultants, LLC, and Central Texas Regional Water Supply Corporation (CTRWSC), SWCA Environmental Consultants (SWCA), conducted further intensive cultural resources investigations of the Vista Ridge Regional Water Supply (Vista Ridge) Project in Burleson, Lee, Bastrop, Caldwell, Guadalupe, Comal, and Bexar Counties. The project will involve installation of a 140.2-mile-long, 60-inch-diameter water pipeline from Deanville, Burleson County, Texas, to north-central San Antonio, Bexar County, Texas. The area of potential effects (APE) will consist of the proposed centerline alignment and an 85-foot-wide corridor for temporary and permanent construction easements; however, SWCA surveyed a 100-foot-wide corridor to allow for minor shifts in the alignment. This addendum report details the findings of additional cultural resources investigations between 2016 and 2018, on the alignment. The Vista Ridge Project is subject to review under Section 106 of the National Historic Preservation Act (54 USC 306108) and its implementing regulations (36 CFR 800), in anticipation of a Nationwide Permit 12 from the U.S. Army Corps of Engineers in accordance with Section 404 of the Clean Water Act. In addition, the work is subject to compliance with the Antiquities Code of Texas (ACT) under Permit No. 7295, as the Vista Ridge Project ultimately will be owned by a political subdivision of the State of Texas. Furthermore, all human burials in the state of Texas are protected by law, as per the Texas Health and Safety Code Section 711 General Provisions Relating to Cemeteries and the Texas Administrative Code Title 13, THC, Chapter 22 Cemeteries, Sections 22.1 through 22.6. If human burials are encountered in the Project Area and the remains are determined to be Native American, they will be handled in accordance with procedures established through coordination with the THC; work in the affected area would only resume per THC authorization. Between 2016 and 2018, SWCA investigated approximately 29.5 miles of the current 140.2-mile-long project corridor and the proposed 6.9-mile-long wellfield pipeline that was not previously surveyed during the prior 2015 investigations (Acuña et al. 2016). Investigations consisted of intensive pedestrian survey augmented with shovel testing and hand-excavated auger probes and/or mechanical backhoe trenching in select areas. In addition, SWCA investigated the 25.82-acre terminus site slated for the construction of an integration system (Atwood and Ward 2017). SWCA also surveyed additional mileage, which included rerouted areas that are no longer part of the currently proposed alignment. SWCA excavated 967 shovel tests, 96 auger probes, and 85 backhoe trenches during these additional investigations. SWCA documented or further investigated 28 cultural resources within the Vista Ridge Project during the 2016 to 2018 investigations. Of the 28 resources, seven were isolated finds that did not warrant formal site recording or require additional investigations. The remaining 21 cultural resources include 15 prehistoric sites, three historic sites, and three multi-component sites with both prehistoric and historic cultural materials. Of the 21 sites, two (i.e., 41BP960 and 41BP961) are currently UNDETERMINED regarding eligibility for the National Register of Historic Places (NRHP) or as a State Antiquities Landmark (SAL), and one site (i.e., 41GU177) was determined to be ELIGIBLE for listing on the NRHP and for designation as a SAL. SWCA conducted testing and data recovery excavations at site 41GU177 and the results of testing investigations conducted under Permit No. 7295 are presented as an appendix to this report (Rodriguez et al. 2017); the data recovery investigations of site 41GU177 were completed under Permit No. 8231 and will be a separate report. Additionally, sites 41BP960 and 41BP961 have been avoided by design alignment changes and will not be impacted by the Vista Ridge Project. The remaining 18 cultural resources sites are considered NOT ELIGIBLE for nomination to the NRHP or for designation as SALs and no further cultural resources investigations or avoidance are recommended. In addition, SWCA documented two cemeteries (the Hill Cemetery and the Hoffman Cemetery) during the 2016 to 2018 investigations. Due to subsequent reroutes, the Hill Cemetery (located within the boundaries of site 41BP818) is now avoided and will not be impacted by the project. Mechanical scraping was conducted adjacent to the Hoffman Cemetery in compliance with the Texas Health and Safety Code; no evidence of interments was identified within the project area. In accordance with 36 CFR 800.4 and the ACT, SWCA has made a reasonable and good faith effort to identify cultural resources within the project area. Two sites (i.e., 41BP960 and 41BP961) are recommended as having UNDETERMINED eligibility for listing on the NRHP or for SAL designation and one site (41GU177) is recommended as ELIGIBLE. The remaining 18 are recommended as NOT ELIGIBLE for listing on the NRHP or for SAL designation. Site 41GU177 has been mitigated and the results will be presented in a stand-alone report (Nielsen et al. 2019). The two sites (41BP960 and 41BP961) of UNDETERMINED eligibility have been avoided by design alignment changes and will not be impacted by the project. No further work or avoidance strategy is recommended for the remaining 18 archaeological sites identified during the Vista Ridge Project.