Aquífero Termal De Caldas Novas: Monitoramento Mensal Realizado Pelo Departamento Nacional De Produção Mineral-DNPM

Abstract

The thermal waters of Caldas Novas and Rio Quente in the state of Goias were explored only by natural springs until the year 1960. In the beginnings of the 1970's, a large number of wells had been drilled in the area, which were pumped indiscriminately, giving rise to a large decrease on the potentiometric surface of the thermal aquifer. Since this decade, the DNPM has taken part in several projects to recognize and study the thermal aquifer and, in 1979, a continuous monitoring of the aquifer were started, with measurement of water temperature, flow rates and static level on the wells. Since 1996, after detecting a lowering of over 50 meters in the potentiometric surface of the Araxa Aquifer System, the DNPM implemented a series of procedures, such as the closure of illegal wells, suspension of the granting of new licenses, among several others, which resulted in the recovery of about 30 meters on the level of the aquifer system. The results of this monitoring are presented in this article which also shows a new trend of lowering in the potentiometric surface of the thermal aquifer, after its remaining almost stable for more than 10 years.

Toward Molecular Recognition of REEs: Comparative Analysis of Hybrid Nanoadsorbents with the Different Complexonate Ligands EDTA, DTPA, and TTHA

“…Rare-earth elements (REEs) have been increasingly gaining attention in the last few decades due to their unique electronic, magnetic, and catalytic properties among others, which make them crucial in a large variety of applications such as electronics, metallurgy, wind turbines, high-field-strength magnets for hybrid and electric vehicles, and numerous medical devices, applied in such areas as medical diagnostics (optical bioimaging and MRI). − China is currently the absolutely dominating world producer of REEs, possessing the largest reserves of these elements . However, there are many other REE deposits available that have not been commercially exploited at the moment: namely, those in the central region of Brazil, which rank the country in second position in terms of REE abundance, or several deposits in Europe that are currently being explored and technically and economically assessed . The urge to develop sustainable REE industries that ensures autonomy from the current major producer has made REEs the focus point for many researchers around the world in various disciplines, especially after the European Commission and the U.S. Department of Energy declared them critical raw materials. , For that, not only do REE deposits need to be investigated but also efficient technologies for extraction and separation of REEs in solution need to be established.…”

Phytotoxicity of single and mixed Rare Earth Element (La, Nd and Sm) exposures on Lactuca sativa seed germination and growth

“…Based on their electronic con gurations, lanthanides are classi ed as light (LREE), from lanthanum to europium, and as heavy (HREE), from gadolinium to lutetium (Silva et al 2016). Light REE are more abundant in soils, more soluble and present lower potential for the organic and inorganic complex formation when compared to heavy REE (Andrade 2014; Kabata-Pendias 2011). In soil, REE concentrations varied from 16 to 700 mg kg − 1 (Laveuf and Cornu 2009), and element contents studied, La, Nd, and Sm, 30, 28, and 6 mg kg − 1 , respectively (Loell et al 2011).…”

Avaliação da qualidade das águas termais sulfurosas distribuídas nas fontes da cidade de Poços de Caldas-MG

“…Na cidade de Caldas Novas (GO), o Departamento Nacional de Pesquisa Mineral (DNPM) monitora desde o ano de 1992 a "vazão, a temperatura e o nível estático mensalmente dos poços de águas termais. A medição da vazão é importante para evitar que não haja superexplotação e consequentemente uma exposição do aquífero ao risco de contaminações" (ANDRADE & ALMEIDA, 2012).…”