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ResumoO objetivo deste artigo consiste em comparar os resultados de dois métodos para o dimensionamento do reservatório de água pluvial sugeridos na norma brasileira NBR 15527/2007 e o programa computacional Netuno. Foram calculados os volumes de reservatório para residências em três capitais brasileiras, Belo Horizonte, Recife e Rio Branco, escolhidas por apresentarem características distintas de precipitação. Utilizaram-se, para tanto, dados de três estações pluviométricas com base temporal comum de 44 anos, entre janeiro de 1970 e dezembro de 2014. Observou-se haver maior ou menor dispersão dos resultados entre os métodos de dimensionamento, conforme o regime pluviométrico de cada município. Para o caso do município de Recife (PE), constatou-se não haver tanta discrepância entre os resultados para baixas demandas de água para fins não potáveis, tal como aquele que foi avaliada no presente trabalho. Os métodos que consideram as características de demanda, média de precipitação e área de coleta, como é o caso do Método da Simulação, aparentemente são mais robustos e confiáveis no dimensionamento do volume do reservatório de água pluvial. Palavras-chave AbstractThe purpose of this article is to compare the results of two methods for the design of the rainwater tank suggested by the Brazilian NBR 15527/2007 and the software Netuno. The reservoir volumes were calculated for households in three cities in Brazil, Belo Horizonte (Capital of Minas Gerais State, Brazil), Recife (Capital of Pernambuco State, Brazil) and Rio Branco (Capital of Acre State, Brazil), chosen because they have distinct characteristics of precipitation. It was considered data from three rain gauge stations with 44-yearcommon time base, between January 1970 and December 2014. There was greater or lesser dispersion of results between design methods, according to the rainfall of each municipality. In the case of the city of Recife (PE), there was no such discrepancy between the results for low water demand for non-potable purposes, such as one that was evaluated in this study. The methods that consider the demand characteristics, average precipitation and collection area, such as the Simulation Method apparently are more robust and reliable in design of the rainwater reservoir volume.

Gold mineralization that differs from the classic conglomerate-hosted Au-U mineralization from Serra da Jacobina was found at Serra da Paciência, 6km north-northwest of Pindobaçu town, Bahia State. The mineralization occurs 100 meters south of garimpo Mina Velha and consists of a 40cm-thick gold-bearing vein of massive pyrite hosted in a chloritite (metamorphosed ultramafic dike), which intrudes quartzites of the Cruz das Almas Formation (Jacobina Group). The chloritite has N-S direction, thickness between 1,5 and 2 m and is affected by a reverse fault of 095/63 attitude. Samples of massive pyrite returned Au grades of 336 and 385 ppb. At the garimpo Mina Velha gold mineralization is related to pyrite-bearing quartz veins hosted by chloritite affected by the same reverse fault. Gold values in samples from Mina Velha range from 239 ppb, in the chloritite, to 22,660 ppb, in the pyrite-bearing quartz vein. The gold occurrence related to massive pyrite vein reveals to be a prospective alternative different from the conglomerate-hosted Au-U of the Jacobina Group.

Shallow flows correspond to turbulent flows whose horizontal dimensions are considerably larger than the vertical one. In Hydraulic Engineering, they refer, e.g., to stormwater basins, stabilization ponds for wastewater treatment and aquaculture tanks. Since they involve low flow velocities, a continuous settling process often affects such shallow reservoirs. Therefore, it is important to expand the knowledge about the influence of its geometry on the hydrodynamic behavior and the sedimentation tendency. This paper aims to analyze flow patterns in a rectangular reservoir with symmetrically positioned upstream and downstream channels, taking into account three different flow rates under steady flow regime (0.50, 1.25 and 3.40 L/s). Experimental tests were performed in a laboratory prototype, consisted of a 3.0 m long and 2.0 m wide reservoir, with a maximum depth of 0.30 m. Also, it was applied the WOLF 2D software for numerical modeling of all variants. Experimentally, a symmetrical hydrodynamic behavior was observed only for the lowest flow rate, while the flow pattern was asymmetrical for the other cases. On the other hand, the numerical model indicated hydrodynamic symmetry for all scenarios.