Mateo Rojas

Mateo Rojas, MS 2023

Humanitarian Engineering and Science: Environmental Engineering

Bio: Mateo studied the processing systems of two artisanal and small-scale gold mining (ASGM) communities in the Colombian department of Antioquia to better understand miners’ perspectives of communal gold processing. He hopes to continue leveraging his interdisciplinary education, Mexican-American background, and experiences living abroad to collaborate with Latin American communities on projects that promote sustainable development and social justice.



Project Summary: Artisanal and small-scale gold mining (ASGM) in Colombia has been marginalized to accommodate the growth of multinational large-scale mining (LSM) for decades, leading many ASGM communities to lose access to the mineral deposits they depend on financially. As LSM has grown in Colombia, ASGM has been stigmatized due to the environmental and health consequences of the activities in this sector, especially those of the processing plants where miners transform their ore into gold. These sites are the primary source of the estimated 2000 metric tons of mercury released into the environment every year by ASGM. One intervention that has gained the interest of practitioners in Colombia is the communal gold processing plant, where miners could oversee their own collective clean gold processing instead of relying on mercury-laden processing plants or plants owned by third-party companies. Unfortunately, this model has not been successful in Colombia, and few have sought to identify some of the factors that have inhibited the success of these plants. To respond to this gap and the limitations of past interventions seeking to improve gold processing practices in ASGM, Mateo’s thesis provides a sociotechnical analysis of two processing arrangements in the Colombian department of Antioquia. His research reveals how the unique and dynamic arrangement of gold processing systems reciprocally influences miners’ agencies, forms unique sustainability priorities, and creates opportunities for people to use mining as a meaningful livelihood in ASGM contexts. His thesis ultimately shows that interventions seeking to improve gold processing practices in ASGM would benefit from considering the extent to which miners’ agencies would be preserved or neglected and integrating miners into the project from the outset.


Mateo conducted his thesis research as a Research Assistant for an NSF-funded Partnerships in International Research and Education (PIRE) grant titled Responsible Mining, Resilient Communities. Researchers on this interdisciplinary, international, and multi-institutional project have embraced the vast network present across eight academic institutions and dozens of ASGM communities to carrying out research about Peruvian and Colombian ASGM since 2018. 



Abandoned Processing Plant

Mateo built on this network during his time in Colombia, which started with a preliminary visit in March 2022 to visit his study sites with a Colombian graduate student studying ASGM. This trip offered him an early opportunity to make connections with potential research collaborators and observe gold processing and mining practices in person. He returned to Colombia in May 2022 and spent two months in the department of Antioquia conducting 35 semi-structured interviews, one focus group, and purposive observation of gold processing practices in the ASGM towns of La María and Frontino. After successfully defending his thesis, Mateo returned to Colombia in March 2023 to conduct follow-up research, receive feedback from his collaborators about his findings, and begin to make plans for his research translation activities. 


As he analyzed his data and formed his conclusions, Mateo presented his research through different disciplinary mediums to understand his observations in Colombia in different ways. He submitted his work to a Science and Technologies Studies (STS) journal and presented for eight universities and three different academic conferences with emphases on humanitarian technology, STS, and mining, metallurgy, and exploration.


Mateo returned to Colombia in August 2023 to engage in the process of research translation, which involves presenting research beyond purely academic audiences to inform decision-makers and promote future work. In addition to transmitting his approach and findings to undergraduate and graduate mining engineering students, Mateo is presenting his research for government agencies, private companies, and nongovernmental organizations interested in improving the gold processing practices in the Colombian ASGM sector.