Intensive Archeological Survey: State Highway 6 at Farm-to-Market Road 2, Grimes County, Texas

On behalf of the Texas Department of Transportation (TxDOT), SWCA Environmental Consultants (SWCA) conducted an intensive cultural resources survey with shovel testing and backhoe trenching from November 29–30, 2017, of approximately 27.55 acres (11.15 hectares) of existing and 10.45 acres (4.23 hectares) of proposed new TxDOT right-of-way (ROW) along State Highway (SH) 6 and Farm-to-Market Road (FM) 2, located approximately 7.0 miles (11.3 kilometers [km]) southeast of Navasota and 11.0 miles (17.7 km) northwest of Hempstead, Grimes County, Texas. Because the project will receive funding from the Federal Highways Administration, it qualifies as an undertaking as defined in Title 36 Code of Federal Regulations (CFR) Part 800.16(y) and, therefore, survey was conducted in compliance with Section 106 of the National Historic Preservation Act (54 U.S. Code 306108). Furthermore, the project must also comply with the Antiquities Code of Texas (9 Natural Resources Code 191). Jason Barrett served as Principal Investigator under Texas Antiquities Permit No. 8213. The total area of potential effects (APE) consists of 27.55 acres (11.15 hectares) of existing and 10.45 acres (4.23 hectares) of proposed new TxDOT ROW along a 1-mile (1.6-km) long stretch of SH 6 slated for improvements to the FM 2 intersection and modifications on two side-by-side SH 6 bridges over Beason Creek. At the time of the investigations, right of entry (ROE) was obtained for all but 3.0 acres (1.2 hectares) of proposed new ROW, all of which is located along the eastern side of SH 6. The typical depth of impacts for the project is variable, with a maximum depth of 20.0 feet (6.1 meters) where improvements to the intersection and modification to the bridges will occur. A background literature review determined that the APE has not been previously surveyed for cultural resources, and that no archeological sites, cemeteries, National Register of Historic Places (NRHP) districts and properties, or historical markers are within the APE or within a 0.6-mile (1-km) radius of the APE. No historic-age buildings or structures were identified within the APE during a review of the TxDOT Historic Overlay Maps (Foster et al. 2006). Field investigations of the existing ROW and 7.0 acres (2.8 hectares) of proposed new ROW for which access has been granted consisted of an intensive pedestrian survey supplemented with the excavation of 15 shovel tests and a single backhoe trench. Areas without ROE were examined from the accessible portions of the APE. The existing ROW has been heavily modified as a result of road construction, ditches, driveways, buried and overhead utilities, and immediately adjacent commercial and industrial development. The proposed new ROW has been modified by farming and ranching practices and infrastructure, as well as some commercial development. SWCA documented two isolated finds (IFs), one prehistoric (IF01) and one historic (IF02), along the margins of the SH 6 at FM 2 survey area. IFs are not eligible for the NRHP or for designation as a State Antiquities Landmark. SWCA recommends a finding of “no historic properties affected” and no further archeological investigations. Cultural resources survey of the currently inaccessible parcels with proposed new ROW is not recommended due to the negligible and heavily modified areas involved

Prime factors of Φ3(x)\Phi_3(x) of the same form

We parameterize solutions to the equality $\Phi_3(x)=\Phi_3(a_1)\Phi_3(a_2)\cdots\Phi_3(a_n)$ when each $\Phi_3(a_i)$ is prime. Our focus is on the special cases when $n=2,3,4$, as this analysis simplifies and extends bounds on the total number of prime factors of an odd perfect number

Intensive Cultural Resources Survey of the Proposed Bagdad Road at County Road 278 Improvements Project, Williamson County, Texas

At the request of Lockwood, Andrews & Newnam, Inc., and on behalf of Williamson County, Texas, SWCA Environmental Consultants conducted an intensive cultural resources survey of the proposed approximately 4,500-foot-long (1371.6 meters [m]) Bagdad Road (County Road [CR] 279) Improvements Project extending 1,000 feet (304.8 m) north and south of CR 278 and 2,500 feet (762.0 m) west-southwest of CR 278 in western Williamson County, Texas. The project area is located between the communities of Liberty Hill and Leander along the intersection of CR 279, also known as Bagdad Road, and CR 278. Since the project involves lands that will be acquired and controlled by Williamson County (a subdivision of the State of Texas), the project is subject to review under the Antiquities Code of Texas (ACT). SWCA conducted the investigations under Texas Antiquities Permit No. 8044. The proposed project will involve improvements to the existing Bagdad Road and CR 278 intersection and the construction of new roadway (to be called “River Ranch County Park Road”) west-southwest of the intersection, to allow access to the River Ranch County Park. The planned improvements will be located along the existing Bagdad Road from 1,000 feet (304.8 m) north and south of CR 278. The planned new roadway will extend 2,500 feet (762.0 m) west-southwest of the Bagdad Road and CR 278 intersection to the southeastern edge of River Ranch County Park. Overall, the direct area of potential effects (APE) encompasses approximately 13.8 acres (5.6 hectares [ha]), composed of a 4,500-foot-long (1371.6 m) and approximately 25- to 70-foot (7.6- to 21.3-m) wide proposed right-of-way. The depth of impacts is anticipated to extend 3 to 4 feet (0.9 to 2.2 m) below ground surface for roadway construction and up to 10 feet (3.1 m) for culverts. Investigations included a background and historic map review, and an intensive pedestrian survey with shovel testing of the proposed APE. The background review determined that no previously conducted cultural resources investigations and no previously recorded archaeological sites are located within the direct APE. One cultural resources testing project and eight previously recorded archaeological sites are located within a 1-mile radius of the project area. The review of maps on the Texas Department of Transportation Historic Overlay, U.S. Geological Survey TopoView, and Historic Maps revealed one possible historic-age structure adjacent to the APE. The field investigations included extensive visual inspection and intensive pedestrian survey with shovel testing throughout the APE. The investigations revealed the APE is along the existing county roads and within the undeveloped land and residential development that surrounds the roadways. The undeveloped land consists of rocky uplands with exposed limestone bedrock, cobbles, and gravels along the ground surface. Previous and current impacts to the area include clearing and grading activities, construction of existing roads and driveways, associated infrastructure installation, impervious cover, gravel filled areas, residential development, and overhead and buried utility installations particularly along and immediately adjacent to the roadways. SWCA excavated a total of 15 shovel tests within the APE, which revealed shallow soils atop of bedrock. SWCA’s investigations exceeded the Texas Historical Commission’s requirements and identified no prehistoric or historic cultural materials within the APE. One historic-age standing structure was identified during the historic map review and field investigations immediately adjacent to the APE located on the southeast corner of the intersection of Bagdad Road and CR 278. An SWCA architectural historian evaluated the structure and determined that based on historic aerials the date of construction is circa 1940, but that while it is historic age it lacks integrity and is recommended as NOT ELIGIBLE for the National Register of Historic Places (NRHP). In accordance with the ACT and 36 Code of Federal Regulations (CFR) 800.4, SWCA made a reasonable and good faith effort to identify cultural resources within the direct APE. As no archaeological sites were identified that may meet the criteria for designation as a State Antiquities Landmark, per 13 Texas Administrative Code 26.12, or standing structures for listing on the NRHP, according to 36 CFR 60.4, SWCA recommends that no further cultural resources investigations are warranted within the surveyed portions of the APE and that a determination of No Historic Properties Affected be granted for the proposed project

Intensive Cultural Resources Survey for the Pilot Knob Wastewater Interceptor Project, Travis County, Texas

On behalf of Brookfield Residential, SWCA Environmental Consultants (SWCA) conducted an intensive cultural resources investigation of the proposed Pilot Knob Wastewater Interceptor Project in southeast Austin, Travis County, Texas. The project involves the construction of a roughly 2.1-mile-long wastewater interceptor line with an 80-foot temporary and 40-foot permanent easement, and encompasses 20.0 acres. The project has two components: the initial 1.7-mile-long wastewater interceptor and the additional 0.34- mile-long Phase 2 extension. The initial project alignment begins at Dee Gabriel Collins Road, located approximately 0.6 mile northwest of the intersection of U.S. Route 183 and Farm-to-Market (FM) 812. The proposed line traverses undeveloped land for 1.7 miles and terminates approximately 0.6 mile east of the intersection of McKinney Falls Parkway and Colton Bluff Springs Road. The Phase 2 additional alignment will extend 0.34 mile north-northeast of Dee Gabriel Collins Road before terminating in an undeveloped tract. The depths of project impacts are currently unknown, but horizontal directional bores are proposed at road and drainage crossings and are not expected to exceed 15–20 feet below ground surface. The area of potential effects (APE) for the project is approximately 2.1 miles long and 80 feet wide, encompassing 20.0 acres. The proposed APE is within a semi-rural setting that is quickly becoming more urbanized. As portions of the initial project alignment traverse potential waters of the U.S., the project must comply with application requirements for a U.S. Army Corps of Engineers Fort Worth District Section 404 permit in accordance with 33 Code of Federal Regulations (CFR) Part 325, Appendix C (Processing Department of Army Permits: Procedures for the Protection of Historic Properties; Final Rule 1990; with current Interim Guidance Document dated June 24, 2002) and with Section 106 of the National Historic Preservation Act (16 USC 470), and its implementing regulations (36 CFR 800). Portions of the initial project alignment within the 100-year floodplain may also be subject to permitting by the Federal Emergency Management Agency and require Section 106 compliance. Portions of the additional project alignment are on lands slated for ownership by the Pilot Knob Municipal Utility District No. 1, a political subdivision of the State of Texas, as a consequence, the project must comply with the Antiquities Code of Texas in addition to Section 106 of the NHPA and its implementing regulations. Consequently, all work was conducted in accordance with the standards and guidelines of the Antiquities Code of Texas under Antiquities Permit No. 7287. The goal of the work was to locate all prehistoric and historic archaeological sites within the proposed APE, establish vertical and horizontal site boundaries as appropriate, and evaluate the significance and eligibility of all recorded sites for inclusion to the National Register of Historic Places (NRHP). The investigations were initiated with a background review of previous work, historic map review, and an archival review of the APE parcels. Field work involved an intensive pedestrian survey with shovel testing of the APE. The background review determined that portions of the APE have been previously surveyed and that one archaeological site (41TV2366) is recorded within the APE. Site 41TV2366 is an early-twentieth-century farm complex and is not considered eligible for inclusion to the NRHP or for designation as a State Antiquities Landmark (SAL). Historic maps revealed six possible historic-age structures and one cemetery within or immediately adjacent to the APE. Field work for the initial alignment was conducted on October 29, 2014, with a total of 19 shovel tests excavated in portions of the APE. Field work for the additional project alignment was conducted on May 21, 2015, with a total of three shovel tests excavated within the APE. The APE exhibits prior modifications from residential and agricultural development and associated utility installations. The investigations revisited site 41TV2366, verified the location of a historic-age cemetery, and recorded site 41TV2480. Site 41TV2366 is a historic-age farm complex and is considered not eligible for inclusion in the NRHP. No avoidance or additional work is required. The historic-age Collins Cemetery is located 93 feet from centerline and is protected under 711.035(f) and 711.010(a)(b) of the Health and Safety Code of Texas, and as a result, avoidance of the cemetery is required by state law. However, based upon the current alignment, the centerline is over 90 feet north of the cemetery fence and adequately avoids the cemetery. Therefore, the Collins Cemetery will not be impacted by construction activities associated with the Pilot Knob Interceptor Project. As such no additional work is required. Site 41TV2480 is a historic-age circa 1955 residence identified and recorded along the margin of the additional alignment project alignment. No historic-age artifacts associated with 41TV2480 were observed in the current APE, and the residence has been continuously lived in as well as modified compromising its integrity. Based on these factors, site 41TV2480 is recommended as ineligible for inclusion in the NRHP or for designation as an SAL, and no further work is recommended. In accordance with 36 CFR 800.4, SWCA has made a reasonable and good faith effort to identify cultural resources within the APE. As no properties were identified that meet the criteria for listing in the NRHP, according to 36 CFR 60.4, or for designation as an SAL, according to 13 Texas Administrative Code 26.12, SWCA recommends no further cultural resources investigations are warranted within the project APE

Addendum Report: Additional Cultural Resources Investigations of the Vista Ridge Regional Water Supply Project in Burleson, Lee, Bastrop, Caldwell, Guadalupe, Comal and Bexar Counties, Texas

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

The religious, secular and spiritual climate of higher education: Exploring Penn State’s Pasquerilla Center through case study

This dissertation study explored the campus climate of Penn State University for religious, secular, and spiritual identities through use of Strange and Banning’s Educating by Design theoretical framework. Specifically, it employed use of case study methodology to qualitatively examine how the Pasquerilla Center, the largest Multifaith Center in North America, as well as the Center for Spiritual and Ethical Development, engaged in providing institutional policies and practices that supported all forms of religious and non-religious identities. The study considered how constructivism affected perceptions of campus climate by students from Muslim, Jewish, Catholic Christian, and Protestant and Evangelical Christian religious identification. Four dimensions of campus climate-- physical environments, aggregated environments, constructed environments, and organizational environments provided the guiding framework from which the study was analyzed. The study revealed that while physical environments were effective in supporting certain identities, namely Muslim and Jewish students, other students found their campus experience to be less welcoming. Additionally, the presence of a physical environment, such as a multifaith center, may pacify the rest of the general campus from taking responsibility for supporting religious, secular, and spiritual identities. The study also revealed a general “interaction without intersection” of individuals across religious communities until the introduction of a campus staff/ administrator, and office and a specific focus was placed upon such intersections. The study offered several considerations regarding future research and policy and practice implication, including the need for more prayer and meditation spaces, kosher and halal dietary options, and in general more inclusive institutional policies related to religious holiday observances

Matching the Scales of Planning and Environmental Risk: an Evaluation of Community Wildfire Protection Plans in the Western US

Theory predicts that effective environmental governance requires that the scales of management account for the scales of environmental processes. A good example is community wildfire protection planning. Plan boundaries that are too narrowly defined may miss sources of wildfire risk originating at larger geographic scales whereas boundaries that are too broadly defined dilute resources. Although the concept of scale (mis)matches is widely discussed in literature on risk mitigation as well as environmental governance more generally, rarely has the concept been rigorously quantified. We introduce methods to address this limitation, and we apply our approach to assess scale matching among Community Wildfire Protection Plans (CWPPs) in the western US. Our approach compares two metrics: (1) the proportion of risk sources encompassed by planning jurisdictions (sensitivity) and (2) the proportion of area in planning jurisdictions in which risk can originate (precision). Using data from 852 CWPPs and a published library of 54 million simulated wildfires, we demonstrate a trade-off between sensitivity and precision. Our analysis reveals that spatial scale match—the product of sensitivity and precision—has an n-shaped relationship with jurisdiction size and is maximal at approximately 500 km2. Bayesian multilevel models further suggest that functional scale match—via neighboring, nested, and overlapping planning jurisdictions—may compensate for low sensitivity. This study provides a rare instance of a quantitative framework to measure scale match in environmental planning and has broad implications for risk mitigation as well as in other environmental governance settings

Cultural Resources Survey of Portions of the Rio Bravo LNG Pipeline on Port of Brownsville Lands, Cameron County, Texas

On behalf of Ecology and Environment, Inc. (E & E), Rio Grande LNG, LLC, and Rio Bravo Pipeline Company, LLC (RB Pipeline), SWCA Environmental Consultants (SWCA) conducted cultural resources surveys of portions of the Rio Bravo Pipeline on lands owned or controlled by the Port of Brownsville (Port) in Cameron County, Texas. Rio Grande LNG, LLC proposes to construct a natural gas liquefaction facility and liquefied natural gas (LNG) export terminal (Terminal) in Cameron County, Texas, along the north embankment of the Brownsville Ship Channel. In concert with the Terminal, RB Pipeline proposes to construct an associated pipeline system (Pipeline System/Project) within Cameron, Willacy, Kenedy, Kleberg, and Jim Wells Counties, Texas to allow for interconnection with a network of existing pipelines that traverse the northern end of Kleberg County and Jim Wells County. The proposed Pipeline System/Project will collect and transport natural gas to the Terminal site. In compliance with the Federal Energy Regulatory Commission and U.S. Army Corps of Engineers permitting requirements and oversight, SWCA conducted cultural resources investigations in compliance with Section 106 of the National Historic Preservation Act (NHPA) (54 U.S.C. 306108) and its implementing regulations in 36 Code of Federal Regulations 800. Although the entire Project is subject to compliance with Section 106 of the NHPA, this stand-alone report specifically addresses portions of the alignment that will be located on lands owned by the Port of Brownsville (Port). Since the Port is a political subdivision of the state, investigations were conducted in compliance with the Antiquities Code of Texas (ACT) under ACT Permit No. 8588 administered by the Texas Historical Commission (THC). The data in this report is also presented in Addendum IV (Carpenter et al., 2020) to the final report (Nielsen et al., 2016) of the overall investigations. The investigations covered 0.58 mile (0.93 kilometers [km]) of a 50-foot wide reroute adjacent to previously surveyed 200-foot-wide (60.96-meter [m]-wide) pipeline survey corridor, and 0.31 mile (0.50 km) of proposed access roads within a 50-foot-wide (15.24-m-wide) access roads survey corridor, for a Project Area total of approximately 5.39 acres within Port property. The cultural resources investigations included a background and historical map review, and an intensive pedestrian survey with subsurface testing. The background review identified nine previously conducted archaeological surveys within a 1- mile radius of the Project Area, three of which intersect the current Project Area. The background review identified no previously recorded archaeological sites within the Project Area; however, seven archaeological sites are within a 1-mile radius none of which are immediately adjacent (within 300 feet [91.44 m]) to the Project Area. In addition, a review of historical maps determined that there are no historic-age structures or features mapped within or immediately adjacent to the Project Area. SWCA archaeologists conducted the cultural resources intensive pedestrian survey on October 22, 2018. The investigation revealed an extensively disturbed setting due to historic & modern development in the area mainly associated with the Port. SWCA archaeologists excavated a total of nine shovel tests within the Project Area all negative for cultural materials. No cultural materials or features or historic-age structures were identified within the Project Area during the field survey. In accordance with the ACT and Section 106 of the NHPA, SWCA has made a reasonable and good faith effort to identify cultural resources within the Project Area of Potential Effects (APE). No cultural resources were identified within the Project Area during the current investigations. Accordingly, no further investigation is recommended for the assessed sections of the Project Area. The THC concurred with these findings and recommendations on January 14, 2020. No artifacts were recovered; documentation will be curated at the Texas Archeological Research Laboratory of The University of Texas at Austin

Archetypes of Community Wildfire Exposure from National Forests of the Western US

Risk management typologies and their resulting archetypes can structure the many social and biophysical drivers of community wildfire risk into a set number of strategies to build community resilience. Existing typologies omit key factors that determine the scale and mechanism by which exposure from large wildfires occur. These factors are particularly important for land managing agencies like the US Forest Service, which must weigh community wildfire exposure against other management priorities. We analyze community wildfire exposure from national forests by associating conditions that affect exposure in the areas where wildfires ignite to conditions where exposure likely occurs. Linking source and exposure areas defines the scale at which crossboundary exposure from large wildfires occurs and the scale at which mitigation actions need to be planned. We find that the vast majority of wildfire exposure from national forests is concentrated among a fraction of communities that are geographically clustered in discrete pockets. Among these communities, exposure varies primarily based on development patterns and vegetation gradients and secondarily based on social and ecological management constraints. We describe five community exposure archetypes along with their associated risk mitigation strategies. Only some archetypes have conditions that support hazardous fuels programs. Others have conditions where managing community exposure through vegetation management is unlikely to suffice. These archetypes reflect the diversity of development patterns, vegetation types, associated fuels, and management constraints that exist in the western US and provide a framework to guide public investments that improve management of wildfire risk within threatened communities and on the public lands that transmit fires to them

Social Vulnerability to Large Wildfires in the Western USA

Federal land managers in the US can be informed with quantitative assessments of the social conditions of the populations affected by wildfires originating on their administered lands in order to incorporate and adapt their management strategy to achieve a more targeted prioritization of community wildfire protection investments. In addition, these assessments are valuable to socially vulnerable communities for quantifying their exposure to wildfires originating on adjacent land tenures. We assessed fire transmission patterns using fire behavior simulations to understand spatial variations across three diverse study areas (North-central Washington; Central California; and Northern New Mexico) to understand how different land tenures affect highly socially vulnerable populated places. Transboundary wildfire structure exposure was related to populations with limited adaptive capacity to absorb, recover and modify exposure to wildfires, estimated with the Social Vulnerability Index using US Census unit data (block groups). We found geographic heterogeneity in terms of land tenure composition and estimated fire exposure. Although high social vulnerability block groups covered small areas, they had high population and structure density and were disproportionately exposed per area burned by fire. Structure exposure originated primarily from three key land tenures (wildland-urban interface, private lands and national forests). Federal lands proportionately exposed, on an area basis, populated places with high social vulnerability, with fires ignited on Forest Service administered lands mostly affecting north-central Washington and northern New Mexico communities