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A qualidade da água está relacionada aos fenômenos naturais e às ações antrópicas, influenciada pelo uso e ocupação do solo na bacia hidrográfica. Devido à alta produção e o manejo inadequado dos resíduos sólidos a Lei 12.305/2010 (Política Nacional de Resíduos Sólidos) foi criada, a fim de reduzir os impactos socioeconômicos e ambientais decorrentes deste. Nesse contexto, o objetivo desta pesquisa foi identificar os riscos de impactos ambientais pela presença de disposição final de resíduos sólidos na Bacia do Rio Vermelho, com estudo de caso no lixão do município de Goiás. Constatou-se impactos negativos no meio físico e no meio antrópico, causados pelos lixões na bacia. Foi observado que a Bacia do Rio Vermelho está em área frágil, altamente susceptível a contaminação pelos lixões. São necessários o planejamento e a tomada de ações imediatas, a fim de extinguir o lixão e criar um aterro sanitário, para reduzir os impactos ambientais.

Detection of gross alpha and beta radioactivity is important for a quick surveying of both natural and anthropogenic radioactivity in water. Furthermore, gross alpha and gross beta parameters are included in Brazilian legislation on quality of drinking water. In this work, a low background liquid scintillation spectrometer was used to simultaneously determine gross alpha and gross beta in samples of the public water supplies in the state of Goiás, Brazil, during 2010-2015. Sample preparation involved evaporation to concentrate the sample ten-fold. The results indicate that the water meets the radioactivity standards required by the regulations MS 2914/2011 of the Brazilian Department of Health. Concerning the high level of censored observations, a statistical treatment of data was conducted by using analysis methods of censored data to provide a reference value of the gross alpha and beta radioactivity in drinking water from the state of Goiás. The estimated typical activities are very low, 0.030 Bq.L-1 and 0.058 Bq.L-1, for gross alpha and gross beta, respectively.

In 1987, in Goiânia (Goiás, Brazil) a radiological accident occurred due to the violation of a capsule containing Cs-137, previously used in radiotherapy equipment. The source contained caesium chloride and, due to the high solubility of this compound in water, there was contamination of people and consequent dispersion in the environment. The waste was discharged into the river network and after four years, a high concentration of Cs-137 was still observed in the sediments at the Rochedo dam, in Piracanjuba, Goiás, 80 kilometres downstream of the Metropolitan Region of Goiânia. This research analysed the Cs-137 activity in sediment samples and water samples from the Rochedo dam, with the purpose of updating the radiological monitoring data of the region and also to verify if the perceived values would indicate any threat to the environment and public health. The Cs-137 activity was detected in 93.8% of the analysed samples, whose values varied from traces to 2.25 Bq/L. The results for all water samples and for 53.8% of the sediment samples were below the minimum detectable activity by the equipment. This study showed that Cesium-137 activity seem to be very low in the water resources and sediments of the Rochedo dam and it seems to not offer radiological risks for public health and the environment.