OBJECTIVES/GOALS: In 2022, Chicago created the COVID-19 Response Corps, a cohort of community health workers (CHWs), trained to conduct contact tracing and vaccine outreach. Through an Earn and Learn program, corps members studied community-engaged participatory research, and co-led a rapid assessment with researchers to assess vaccine hesitancy in communities. METHODS/STUDY POPULATION: The Chicago COVID-19 Community Response corps worked to mitigate COVID-19 transmission in disadvantaged neighborhoods by activating CHWs, a diverse public health workforce from communities most affected by health and economic inequities. The Earn and Learn Program allotted 600 corps members up to 7.5 hrs/week of paid capacity building opportunities to learn new skills, pursue training programs, or college courses. Embodying a praxis of participatory action research and intergenerational organizing, corps members co-designed research questions and survey instruments, pilot tested the tools, trained other corps members on how to recruit and collect data, and contributed to the analysis and interpretation of the results. They generated evidenced-informed solutions to address future real-world problems. RESULTS/ANTICIPATED RESULTS: Corps members brought insight, cultural literacy, and lived experience that was invaluable in reaching the priority population of unvaccinated Chicagoans. They enhanced all aspects of the rapid assessment while conducting their work safely and comfortably in neighborhoods that outsiders consider challenging. Community member responses as to why they had not yet received a COVID-19 vaccine included being unable to risk putting what they saw as a rushed or improperly tested product into their bodies, to not being able to risk becoming ill even temporarily due to the potential for lost wages, as well as having other priorities in their lives which took precedence over concern about COVID-19, such as paying bills and feeding their families. DISCUSSION/SIGNIFICANCE: Research and evaluation benefits from the inclusion of CHWs. They are agile agents of change with the potential to replenish and repair trust in a fractured public health system. Engaging CHWs in evaluation work can strengthen community-academic partnerships and enhance the understanding of challenges and solutions to improving community health.

Unglaciated coastal areas in East Antarctica provide records of past ice sheet and glacier fluctuations and subsequent environmental conditions. In this paper we review lithological, geochemical, diatom and radiocarbon data from sediment records from inland and epishelf lakes in Bunger Hills, East Antarctica. While some hilltops were unglaciated during the Last Glacial Maximum, till deposits in lake basins indicate infilling by glacier ice prior to the Holocene. Proglacial sedimentation occurred in lakes during the early Holocene. Around 9.6 ka bp, deposition of marine sapropel started under relatively warm climate conditions. Inland lakes were affected by high clastic input from meltwater runoff until c. 7.9 ka bp, when deposition became highly organic and biogenic proxies indicate a period of cooler conditions. Epishelf lakes experienced a decrease in water exchange with the ocean and increased freshwater input around 7.7 ± 0.2 ka bp and after 2.2 ka bp. This probably resulted from grounding line advances of the bounding glaciers, which could be either controlled by relative sea level (RSL) lowering and/or climate-driven glacier dynamics. The absence of marine sediments in the postglacial record of Algae Lake indicates that Holocene RSL probably reached a maximum at or below 10 m above present sea level.

The Protocol on Environmental Protection to the Antarctic Treaty requires that past and present work sites be cleaned up unless removal would result in greater adverse environmental impact than leaving the contaminant in its existing location. In the early 1990s Australia began the documentation of contaminated sites associated with its research stations, which resulted in an extensive record of contamination at abandoned stations and waste-disposal sites. Currently the technical capability to remediate these sites does not exist because of environmental challenges that are unique to the cold regions. Investigations indicate that clean-up operations in the past have proceeded without adequate precautions and without effective monitoring. To address these problems, three research priorities have been identified to assist meeting international and national obligations to clean up these sites. They are: understanding contaminant mobilisation processes; development of ecological risk assessment for use in monitoring and setting priorities; and development of clean-up and remediation procedures. This study provides sufficient information to guide the completion of a clean-up at Casey Station and to indicate how other similar sites should be managed. The next stage is to develop the theory into an operational plan to include detailed protocols for clean-up, monitoring, site remediation, and management of the waste stream from site to final repository. To achieve this, the Australian Antarctic Division has established a contaminated sites taskforce to facilitate the transition from research and development of techniques to implementation of suitable clean-up options.

A 100 cm long sediment sequence was recovered from Beaver Lake in Amery Oasis, East Antarctica, using gravity and piston corers. Sedimentological and mineralogical analyses and the absence of micro and macrofossils indicate that the sediments at the base of the sequence formed under glacial conditions, probably prior to c. 12 500 cal. yr BP. The sediments between c. 81 and 31 cm depth probably formed under subaerial conditions, indicating that isostatic uplift since deglaciation has been substantially less than eustatic sea-level rise and that large areas of the present-day floor of Beaver Lake must have been subaerially exposed following deglaciation. The upper 31 cm of the sediment sequence were deposited under glaciomarine conditions similar to those of today, supporting geomorphic observations that the Holocene was a period of relative sea-level highstand in Amery Oasis.

Analyses on a sediment core collected from the Windmill Islands, East Antarctica are used to demonstrate that climatic conditions in this region prior to the Last Glacial Maximum were similar to those during the Holocene and that the area was overrun by ice at some stage between 26 kyr BP and the onset of biogenic sedimentation 11 kyr BP. The 10.9 m long core was taken from a marine inlet (epishelf lake) on Peterson Island and is predominantly a sapropel of Holocene age. Material in the lower part of the core includes a till layer lain down during the last glacial in the region and below this till is material which has been dated to 26 kyr BP. Geochemical analyses conducted on the core demonstrate similarities between the Holocene sequence and the preglacial material. The Holocene sequence shows enhanced biogenic production and periods of open water around 4 kyr BP, suggesting a climatic optimum around that time. A subsequent decline in conditions, probably a colder climate with greater extent of sea ice, is evident from 1 kyr BP to the present. The data support results from ice core studies on nearby Law Dome, which suggest there was a period of warming around 11.5 to 9 kyr BP, that recent summer temperatures are low relative to a few centuries ago, and that increasing winter temperatures are the main contributing factor to a recent overall warming in the region.