I Dig UCI - 2023-24 Pavement Trench Report

Bonita Camp at UC Irvine: Trench J, Unit #11

Archaeological Report (2023-2024)

Chau Phan

Under the Supervision of Dr. Straughn

INTRODUCTION

1.1 Project Background

Each Saturday during the academic quarter when the course Anthro 148, colloquially referred to as "I Dig UCI," is offered, upper-level undergraduate students engage in archaeological fieldwork. This pedagogical endeavor serves as an initiation into the practice of archaeological excavation, offering students first-hand exposure to research design and methodologies involved in archaeological recovery. Notably, the excavation targets the oldest extant structures on the university campus, representing some of the earliest vernacular architecture within Orange County. Although ostensibly structured as a course in archaeological field methods, the instruction. The excavations undertaken by undergraduate students continue to yield discoveries that contribute to a deeper understanding of the historical milieu surrounding the establishment and evolution of the UCI campus within the context of the Irvine Ranch’s transformation into a city of some 350,000 residents.

1.2 Location, Topography, Geology

Bonita Camp is situated on the southeast side of the University of California, Irvine campus behind the recreational center. The area around the three remaining structures is largely undeveloped due to its proximity to open drainage channels. While these structures have been used for university purposes, the site is currently under facilities management since 2007 following closure of the “Farm School” that occupied the structures. As such, the remaining area of Bonita Camp is designated as “maintenance” until administrative directives dictate otherwise.

Bonita Camp was an outpost of the former Irvine Ranch which has occupied the traditional territory of the Acjachemen and Tongva peoples. Positioned within the geological region known as the Los Angeles Basin, the UC Irvine campus as a whole is part of the broader Basin and Range system. The site’s topography is relatively flat, at the base of the San Joaquin foothills, with surrounding areas typified by undulating hills and valleys. Geologically, the area's substratum primarily comprises sedimentary rocks such as sandstone, shale, and limestone, deposited over millennia in prehistoric marine environments.

ARCHAEOLOGICAL AND HISTORICAL BACKGROUND

The University of California, Irvine, occupies a segment of the ancestral and unceded territories belonging to the Acjachemen and Tongva peoples, areas subjected to dispossession through a series of settler colonial violence. Coupled with an absence of federal recognition, these indigenous communities have been rendered ineligible to pursue the reclamation of their ancestral lands. The area would evolve into one of the initial cattle encampments under the purview of the Irvine Ranch, with the establishment of UCI in 1965 representing a subsequent developmental stage.

During the late 1960s, the site accommodated Professor Dwayne Metzker's ethnographic research, conducted from 1968 to 1969. This initiative facilitated the engagement of indigenous experts on campus, affording students direct exposure to and analysis of their cultural traditions and practices. The infrastructure, comprising three agricultural edifices, served as domiciles for ethnographic informants, including a Samoan boatbuilder and Guatemalan weavers, thereby earning designation as the "Social Sciences Farm." This locus not only provided a platform for the dissemination of traditional craftsmanship but also served as an experimental hub for pedagogical and research methodologies within the academic community.

Concurrently, the emergence of countercultural movements intersected with activities at the farm, fostering the establishment of a commune by free-thinking students. This development led to the occupation of ancillary structures, subsequently repurposed for a 4H club and the Farm School, an innovative K-8 educational initiative administered by the School of Social Sciences from 1970 to 2007.

METHODOLOGY

Following the aim of the curriculum in training students in archaeological fieldwork, multiple excavations were held for the Fall Quarter. Instruction encompassed delineating site parameters, employing compass orientation to establish cardinal points for trench layout. Initial rounds involved the execution of shovel test pits, progressing towards an excavation trench as students became more skilled in their work.

After showing enough competency, students were tasked with excavating ten distinct locations that were designated as Trench J Units 1-10. The primary objective was to investigate a prominent concrete structural feature that had surfaced, seeking to elucidate its temporal relationship within the site's chronology. Historical aerial photos indicated the emergence of this feature post-World War II, yet the rationale behind its construction and subsequent concealment remains unresolved.

After observations made during the excavation of the units that initially exposed the pavement, an additional unit, Unit 11, was opened to locate the southern end of this concrete structure. While Unit 11, did not encounter the pavement’s terminus, it yielded a profusion of material culture such as ceramics, metalwork, charcoal, and glass. As such, the unit’s dimensions were expanded from an initial 1m x 1m to 2m x 2m, in an endeavor to maximize the recovery of material culture and a brick and charcoal feature. This expansion proved pivotal, as prior discoveries had exhibited irregularity and failed to yield comparable artifact densities.

EXCAVATION AND FINDINGS - Trench J Unit 11

Students initiated excavation of a 1m x 1m unit positioned with the aim to reveal the southern extent of the concrete pavement. The excavation process followed a locus-based approach, with contexts delineated by soil color, composition, findings, or the presence of features.

Locus 1 was characterized by a sandy silt soil matrix, typical of the site's topsoil. Initial clearance involved the removal of vegetation and plant roots. The top elevation was recorded at 18cm, and the bottom at 4cm. Material artifacts, including ceramics and various plastics, suggested recent landscaping activities. Additionally, fragments of charcoal were discovered within the matrix.

Locus 2 shared a similar matrix composition, consisting of sandy clay loam. The removal of plant roots continued in this area. Material findings expanded significantly to include ceramics, glassware, plastics, and metals. Of particular interest was the emergence of what appeared to be a brick fragment along the trench's border wall. This discovery prompted the decision to expand Trench J Unit 11 (J-11) into a 2x2 meter unit in hopes of uncovering further material culture. To maintain momentum, assistance was sought from four additional participants from the "I Dig UCI" team.

Locus 1 of the newly expanded Trench J Unit 11 closely resembled the original, characterized by a topsoil containing approximately 40% sand, small fragments of charcoal, and traces of vegetation. With the increased presence of charcoal and the appearance of brick fragments, questions arose about their potential connection. The excavation continued to yield a plethora of material culture, including ceramics, glass, lithic fragments, metals, plastics, and various other items.

Locus 2 was marked by a transition to a densely packed clay matrix, still containing sand and charcoal as seen previously. The presence of large roots complicated the excavation process, extending throughout the perimeter. Material findings remained abundant, encompassing ceramics, glassware, bone fragments, metals, plastics, shells, and more. Notably, the charcoal fragments increased in size compared to previous discoveries.

Locus 3 marked a significant development with the emergence of a feature. With the trench now fully leveled, the bottom elevation was measured at 25cm. This feature consisted of a row of bricks, approximately 8-10 in number, arranged arbitrarily along a line. Additionally, a metallic object was observed amidst the bricks, although its exact identity was obscured by wear and tear. The nature of this feature remained uncertain at this stage. Material discoveries began to taper slightly, with glass, lithic fragments, metals, and plastics being the primary findings. A metal pipe is seen to be poking out the southern side of the trench.

Locus 4 underwent a notable shift in matrix composition, transitioning from hard compacted clay to much softer soil. Given the diminishing likelihood of the brick structure being a remnant of the kiln, it was decided to remove it to facilitate further excavation. Pebbles were strewn throughout this soil. At this juncture, the circular feature was fully exposed, surrounded by an abundance of charcoal, with the metal pipe now fully visible. Numerous plastic fragments, likely originating from a common source, were uncovered. With the cultural layer thinning, soil sifting efforts were halted. The final top elevation was recorded at 30cm, with the bottom at 56cm in the center.

Locus 5 marked the resumption of excavation following the winter break. The soil, affected by significant rainfall, necessitated manual trowel work for sifting. It contained varying amounts of plant material and debris, with sections of the trench exhibiting cave-ins. Soil consistency shifted to a salty, light brown complexion with patches of red and black discoloration attributed to plant decomposition. Surprisingly, material culture once again became prominent, encompassing ceramics, glassware, and metals.

Locus 6 signaled a shift in features with the emergence of a water table. The soil became predominantly muddy with reduced sand content. Metal artifacts persisted, and the previously discovered pipe was removed, revealing it to be unattached to anything.

Excavation of the unit was concluded upon reaching the water table at about 55 cm from the ground surface, with a final elevation for the unit at 58.5 cm. This, in conjunction with the absence of sustained discoveries of material culture, prompted closure of the unit, final documentation, and backfilling.

INITIAL INTERPRETATION

The material culture unearthed in unit J- 11, with its abundance of artifacts compared with other units, offers a number of insights into human activity at the site during the post-WWII period. Initial assumptions about the brick feature suggested it might be remnants of a kiln, though the charcoal briquettes associated with it suggests something more like an impromptu fire pit. Given the hydrology of the site we suspect that a period of significant rains shifted the water channeling across the site, inadvertently burying this feature and preserving various camp items such as metal tools (including nails, a horseshoe, and rusted parts), glassware, and purchased ceramics. The purpose of an unconnected pipe unearthed in the lowest stratigraphic level remains a mystery, as does the prevalence of plastics found throughout various levels. The latter may have been intrusive from rodent burrowing activity, while the former might be connected to the relocation of building B to its current location. Additionally, questions persist about the original concrete feature that prompted the excavation: its function, extent, and when/why it was abandoned and covered with fill.