Personal exposure studies suffer from uncertainty issues, largely stemming from individual behaviour uncertainties. Built on spatial-temporal exposure analysis and methods, this study proposed a novel approach to spatial-temporal modelling that incorporated behaviour classifications taking into account uncertainties, to estimate individual livestock exposure potential. The new approach was applied in a community-based research project with a Tribal community in the southwest United States to address questions on potential livestock exposure to abandoned uranium mines (AUMs). The study aimed to 1) classify Global Positioning System (GPS) data from livestock into three behaviour subgroups – grazing, travelling or resting; 2) calculate the daily cumulative exposure potential for livestock; 3) assess the performance of the computational method with and without behaviour classifications. Using Lotek Litetrack GPS collars, we collected data at a 20-min-interval for two flocks of sheep and goats during the spring and summer of 2019. Analysis and modelling of GPS data demonstrated no significant difference in individual cumulative exposure potential within each flock when animal behaviours with probability/uncertainties were considered. However, when daily cumulative exposure potential was calculated without consideration of animal behaviour or probability/uncertainties, significant differences among animals within a herd were observed, which does not match animal grazing behaviours reported by livestock owners. These results suggest that the proposed method including behaviour subgroups with probability/uncertainties more closely resembled the observed grazing behaviours. Results from the research may be used for future intervention and policy-making on remediation efforts in communities where grazing livestock may encounter environmental contaminants.

This paper explores how Indigenous-led research reframes the impacts and response to environmental disasters in the context of acid mine spills in rural communities of the Southwest United States. The collaborative research project addressing the Gold King Mine Spill (GKMS) designed qualitative methodologies that center Indigenous worldviews and contribute to broader understandings of environmental justice. The research team, led by Diné scholars and community leaders, gathered qualitative responses from 123 adult participants in twelve focus groups from three rural communities on the Navajo Nation. The project incorporated fluent Diné speakers and cultural consultants to lead focus groups in a manner consistent with cultural worldviews. The analysis of the focus group data resulted in original findings that reframe previous understandings of environmental harm by broadening the boundaries to include: 1) social relations across time; 2) social relations across space; 3) spiritual relations; and 4) restoring balance. The findings allow for greater insight into the colonial context of disaster on rural and Indigenous lands and confronts colonial-rooted disasters through Indigenous-informed political action.

Background: On August 5, 2015, the Gold King Mine Spill (GKMS) resulted in 3 million gallons of acid mine drainage spilling into the San Juan River impacting the Dine Bikeyah (traditional homelands of the Navajo people). The Gold King Mine Spill Dine Exposure Project was formed to understand the impacts of the GKMS on the Dine (Navajo). Reporting individualized household results in an exposure study is becoming more common; however, materials are often developed with limited community input with knowledge flowing in one direction from researcher to participant. In this study we examined the development, dissemination, and evaluation of individualized results materials. Methods: In August 2016, Navajo Nation Community Health Representatives (Navajo CHRs) sampled household water, dust, and soil, and resident blood and urine for lead and arsenic, respectively. From May-July 2017, iterative dialogue with a wide range of community partners and a community focus groups guided the development of a culturally-based dissemination process. In August 2017, Navajo CHRs reported individualized results and they surveyed the participants on the report-back process at that time. Results: All of the 63 Dine adults (100%) who participated in the exposure study received their results by a CHR in person and 42 (67%) completed an evaluation. Most of those participants (83%) were satisfied with the result packets. Respondents ranked the individual and overall household results as the most important information they received (69% and 57%, respectively), while information on metals exposures and their health effects were the least helpful. Conclusions: Our project illustrates how a model of environmental health dialogue, defined by iterative, multidirectional communication among Indigenous community members, trusted Indigenous leaders, Indigenous researchers, non-Indigenous researchers, can improve reporting individualized study results. Findings can inform future research to encourage multi-directional environmental health dialogue to craft more culturally responsive and effective dissemination and communication materials.

The Gold King Mine Spill (GKMS) disaster resulted in three million gallons of acid mine drainage-containing arsenic and lead being released into a tributary of the San Juan River. The San Juan River flows through the Navajo Nation and the Diné (Navajo) rely on this river for a variety of purposes lending to unique exposure pathways. We administered questionnaires in three Navajo communities in collaboration with the Navajo Nation Community Health Representatives to obtain frequency and duration data on 43 activities (e.g., praying with river water, fishing from the river). These activities were utilized to conduct a community-based probabilistic risk assessment from exposure to arsenic (As) and lead at three different time points (i.e., pre-GKMS, peak-GKMS, and post-GKMS) for four different exposure scenarios: (1) recreational, (2) cultural, (3) dietary, and (4) aggregate. The aggregate scenario combines exposure from engaging in recreational, cultural, and dietary related activities. Utilizing the Lifeline Community-Based Assessment Software ™ distributions were incorporated for different exposure factors (e.g., hand-to-mouth contacts, transfer efficiency) along with Diné-specific activities (e.g., using the sediment as sunscreen) to estimate dose. The estimated lead and arsenic (As) hazard quotients (HQs) for the recreational, cultural, and dietary scenario for all time points were less than one, indicating no excess non-cancer risks. Only the dietary scenario resulted in an excess cancer risk, with less than 1

Background On August 5th, 2015, 3 million gallons of acid mine drainage was accidentally discharged from the Gold King Mine near Silverton, Colorado into Cement Creek which is a tributary to the Animas and San Juan Rivers. The government-initiated risk assessment only assessed a recreational scenario (i.e. hiker drinking from the river), failing to recognize the deep connection of the Diné (Navajo) with the San Juan River. Methods Utilizing a mixed-methods approach we determined the impacts of the 2015 Gold King Mine Spill (GKMS or Spill) on Diné activities. We developed a questionnaire to collect pre- and post-GKMS Diné activity frequency and duration. Navajo Nation Community Health Representatives administered the questionnaire to 63 Diné adults and 27 children living in three Navajo communities along the River. Results Through analysis of the focus group transcripts we identified 43 unique activities between the Diné and San Juan River. There were significant reductions in the total number, frequency, and duration of livelihood, dietary, recreational, cultural/spiritual and arts and craft activities. On average, Diné activities with the San Juan River following the GKMS decreased by 56.2%. Significance The significant reduction in activities following the GKMS may lead to long-term trauma, impacting the ability of the Diné to pass down teachings to their children affecting future generations to come. The 43 distinct activities between the Diné and the San Juan River highlight the importance for scientists and disaster responders to consider cultural and spiritual impacts when responding to environmental disasters and conducting risk assessments among Indigenous communities.

Beginning in 2016, the Agency for Toxic Substances and Disease Registry (ATSDR) and the National Environmental Health Association (NEHA) launched a partnership to create a free online course with the goal of building capacity within communities to help remediate and redevelop brownfields sites. Brownfields are land reuse sites often contaminated by harmful chemicals or redeveloped without proper environmental oversight. Due to their potentially hazardous status, brownfields sites can lead to harmful exposures in humans while accentuating and often exacerbating socioeconomic disparities within their communities. As a result of this partnership, NEHA and ATSDR launched the Environmental Health and Land Reuse (EHLR) Certificate Program in 2020. The Journal is pleased to feature this column to highlight an example of how the EHLR Certificate Program was used to build understanding and increase knowledge on this important topic within environmental health students. The findings and conclusions in this column are those of the authors and do not necessarily represent the views or official position of NEHA, ATSDR, or the Centers for Disease Control and Prevention. Furthermore, verbal permission was given by the students to use their work in this column.

A 2010 study identified higher than average incidence of respiratory disease in Shiprock, NM, the largest city in the Navajo Nation. That study suggested that the potential cause was the combustion of solid fuels in in-home heating stoves and that respiratory disease could be greatly reduced by changing indoor heating behaviors and improving heating stove quality. Since the Navajo people are deeply embedded in culture and traditions that strongly influence their daily lives, a new framework was needed to identify feasible heating alternatives that could reduce the negative environmental and health impacts related to solid fuel use while respecting the culture of the Navajo people. The resulting Navajo framework included perception, cultural, and technical assessments to evaluate seven heating alternatives perceived viable by Navajo stakeholders. Cultural experts at the Diné Policy Institute identified potential cultural limitations and motivating factors for each alternative. A limited technical assessment of the health benefits of these options was conducted and integrated into the process. A parallel convergent mixed-methods approach was employed to integrate qualitative and quantitative results. The results and framework developed and presented here may be useful for decision makers in communities heavily reliant on solid fuels for heat, especially Native Nations, where culture plays an important role in the success of any intervention.

Dine College is a key stakeholder and partner with the U.S. Department of Energy in efforts to develop and implement sustainable and culturally acceptable remedies for soil and groundwater contamination at uranium mill tailings processing and disposal sites on Navajo Nation land. Through an educational philosophy grounded in the Navajo traditional living system which places human life in harmony with the natural world, the College has helped guide researchers to look beyond traditional engineering approaches and seek more sustainable remedies for soil and groundwater contamination at former uranium mill sites near Monument Valley, Arizona, and Shiprock, New Mexico. Students and researchers are asking first, what is Mother Earth already doing to heal a land injured by uranium mill tailings, and second, what can we do to help her? This guidance has led researchers to investigate applications of natural and enhanced attenuation remedies involving native plants phytoremediation, and indigenous microorganisms - bioremediation. College faculty, student interns, and local residents have contributed to several aspects of the pilot studies including site characterization, sampling designs, installation and maintenance of plantings and irrigation systems, monitoring, and data interpretation. Research results look promising.

Uranium mining and milling in the Four Corners' area of the American Southwest has had serious negative impacts on American Indian workers, their families, and their communities. In this article, we will examine Navajo education programs which inform citizens about risks and health impacts associated with radiation exposures. Because the Navajo initially had no vocabulary to understand the nature of uranium and its risks, culturally-sensitive programs were developed both to educate and to empower Navajo citizens. These education programs, which were integrated with research, policy implementation, and reclamation, can serve as models for other groups seeking environmental justice.

Disasters can be defined as catastrophic events that challenge the normal range of human coping ability. The technological/human-caused disaster, a classification of interest in this article, is attributable to human error or misjudgment. Lower socioeconomic status and race intersect in the heightened risk for technological/human-caused disasters among people of color. The experience of the Navajo with the uranium industry is argued to specifically be this type of a disaster with associated long-standing psychological impacts. The history of the Navajo with uranium mining and milling is reviewed with a discussion of the arduous efforts for compensation. The psychological impacts of this long-standing disaster among the Navajo are organized around major themes of: (a) human losses and bereavement, (b) environmental losses and contamination, (c) feelings of betrayal by government and mining and milling companies, (d) fears about current and future effects, (e) prolonged duration of psychological effects, (f) anxiety and depression, and (g) complicating factors of poverty and racism. The paper concludes with suggestions for culturally-appropriate education and intervention.