Diagnóstico ambiental urbano do meio físico de Santa Maria - RS

Abstract

The urban environment diagnosis aims at subsidizing the districts in the decisionmaking in the presence of natural resources preservation. This study, specifically, analyze the urban environment aspect of the physical space. The area of this study is the Map of the Geotechnical Engineering Units according to Maciel Filho (1990) of Santa Maria, located in the Central Depression of the State of Rio Grande do Sul. The methodology of this research started with office studies by means of preexisting researchers; geoprocess tools application with the use of the software Spring 4.2 for the thematic maps and cartograms elaboration; identification and characterization of the geotechnical units carried out thereby laboratory assays and 20 assays of hydraulic conductivity (k) the field carried out using the method of excavated piezometer. The study of the aquifer natural vulnerability were accomplished based on GOD method according to Foster and Hirata (1988) and Foster et al. (2003) using data from 36 wells. The spacialization of the tubular wells and the hydraulic conductivity assays in the Map of the Geotechnical Engineering using the Universal Transverse Mercator/UTM coordinate system from Global Position System /GPS. The potentiometer surface was evaluated associated to the cartograms of vulnerability and the potential points of contamination by the use of SURFER 8.0 software adopting mathematical interpolator Kriging. The results shown that related to the characterization geotechnical coherent parameters with the descriptions of the study area and related to the assays of hydraulic conductivity in the field the range of variation was between 10-5 to 10-8 m/s, classifying the units since the high permeability (Gravitational and Fluvial Deposits, Caturrita, Botucatu and Passo das Tropas formations) to the low permeability (Santa Maria Formation, Alemoa Member). For the vulnerability natural index from the aquifers 4 classes were obtained (negligible, low, moderate and high). From all wells analyzed 11 were classified from moderate to high vulnerability situated in the south and north from each geotechnical units of Santa Maria. The results also shown that were identified 35 fuel ranks, 06 cemeteries and 06 areas of garbage deposits. The majority of the potential sources of contamination are prompt and are inserted in sufficiently susceptible areas of ground and the aquifers pollution. The methodology was viable and gave supply to the physical space research.