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The recent increase in cardiovascular and metabolic disease in the Navajo population residing close to the Grants Mining District (GMD) in New Mexico is suggested to be due to exposure to environmental contaminants, in particular uranium in respirable dusts. However, the chemistry of uranium-containing-dust dissolution in lung fluids and the role of mineralogy are poorly understood, as is their impact on toxic effects. The current study is focused on the dissolution of xcontaining-dust, collected from several sites near Jackpile and St. Anthony mines in the GMD, in two simulated lung fluids (SLFs): Gamble's solution (GS) and Artificial Lysosomal Fluid (ALF). We observe that the respirable dust includes uranium minerals that yield the uranyl cation, UO 2 2+ , as the primary dissolved species in these fluids. Dust rich in uraninite and carnotite is more soluble in GS, which mimics interstitial conditions of the lungs. In contrast, dust with low uraninite and high kaolinite is more soluble in ALF, which simulates the alveolar macrophage environment during phagocytosis. Moreover, geochemical modeling, performed using PHREEQC, is in good agreement with our experimental results. Thus, the current study highlights the importance of site-*

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The Teen Science Cafe began participating in the New Mexico Tech Water Resource Education Program in April 2022. Water samples were collected from two areas around Magdalena. Area One included three sample locations between the Magdalena and San Mateo mountains (Forest, Big Crow and New Wilson wells, pipe and stock tanks). Area Two included one sample from the Alamo Reservation (Apachito well) and two north of the reservation, but south of I-40 (House and Oro wells and stock tanks).The pH, specific conductivity, hardness, and dissolved oxygen were measured in the field using a YSI-meter and the LaMotte AQ-2 Chemical Analysis Kit. Other samples were put in plastic bottles and analyzed later in the analytical laboratory at the New Mexico Bureau of Geology and Mineral Resources. Major ions and minor trace metals, specific conductivity, and alkalinity were tested using a Agilent 5900, Agilent 7900 and Dionex ICS-5000, a Metrohm titrator and a conductivity meter. Hardness and total dissolved solids were calculated from the major ion measurements.Water sources in Area One have good water quality with the exception of an elevated fluoride concentration at one of the sources (Big Crow). Hardness, total dissolved solids and conductivity are also below safe drinking cautions. Water sources in Area Two have high values in hardness, conductivity, and total dissolved solids. A high value in uranium (Apachito) has been measured. Sulfates are also a concern. The US Environmental Protection Agency has proposed a non-regulatory Health-Based Screening Level of 10 µg/L for lithium. All of our testing sites, with the exception of Oro, is above this limitation. When sampling a tank, we know that as water evaporates it leaves behind the chemicals suspended or dissolved in the water. This can increase values of water quality constituents such as hardness, fluoride, sulfates, chloride, etc. We don't have this problem when testing wells or pipes.

Improved exploitation of the remaining uranium in the Grants Mineral District, New Mexico, hinges on the development of a mineral-element speciation determination method. Understanding the mobility and leachability of uranium in mine wastes and ores has importance in both industrial and environmental applications. To this end, we are evaluating the applicability of a previously established sequential chemical extraction method (where a sample is exposed to a series of increasingly aggressive reagents) for copper mine waste on three uranium minerals common to New Mexico: the primary ore mineral uraninite (uranium oxide) and the secondary ore minerals meta-autunite (hydrated calcium uranyl phosphate) and meta-tyuyamunite (calcium uranyl vanadate). We evaluated changes to mineral structure and composition via X-ray powder diffractometry and analysis of the leachate via ICP-MS. Sequential exposures to deionized water, 1 M NH 4 -acetate, 0.2 M NH 4 -oxalate, heated 0.2 M NH 4 -oxalate, and 35% H 2 O 2 resulted in appreciable changes to mineral composition and abundance and yielded detectable amounts of uranium, molybdenum, vanadium, selenium, and calcium in the leachate as a result of mineral dissolution and/or desorption. With further refinement (i.e., testing on ore samples of mixed mineralogical composition), this method may be of use in evaluating the leachability and mineralogical makeup of uraniferous material (e.g., ore, waste rocks, tailings).