José Luiz Silvério da Silva

Qualidade de águas subterrâneas captadas em fontes em função da presença de proteção física e de sua posição na paisagem

No meio rural, a agua de consumo humano e frequentemente captada por meio de sistemas precarios. O objetivo do trabalho foi o de monitorar parâmetros fisicos, quimicos e microbiologicos da qualidade de agua subterrânea captada em fontes para uso domestico, relacionando suas posicoes na paisagem e a presenca de protecao fisica. Trinta e cinco fontes de agua subterrânea, localizadas na pequena bacia hidrografica-PBH do Arroio Lino, area rural do Municipio de Agudo - RS, foram amostradas e classificadas quanto a protecao fisica e a posicao na paisagem. Monitoraram-se, de janeiro a agosto de 2002, os seguintes parâmetros da agua: pH, cor, carbono orgânico soluvel total (COST), N-NO3, N-NH3 e fosforo total (PT), Escherichia coli e coliformes totais. Em geral, os parâmetros variaram com a epoca de coleta, ficando ora acima, ora abaixo dos Valores Maximos Permissiveis previstos pelo Ministerio da Saude do Brasil. A posicao das fontes nas cotas mais altas da paisagem da PBH mostrou-se determinante unicamente para a cor e o PT. A protecao rudimentar mostrou-se eficaz para o PT nas fontes posicionadas em cotas altas, no entanto apresentou respostas discrepantes na parte baixa da paisagem, considerando-se os parâmetros COST e N-NO3. A fonte drenada coletiva, sistema recomendado pela assistencia tecnica oficial, mostrou-se a mais eficaz em evitar a contaminacao por Escherichia coli, restringindo tambem coliformes totais, fosforo total e N-NO3 em relacao a fonte individual. A posicao das fontes na paisagem e a presenca de protecao fisica rudimentar podem ser utilizadas como criterio parcial ao uso de fontes para captacao de agua.

A heuristic algorithm for pattern identification in large multivariate analysis of geophysical data sets

This paper aims to present a heuristic algorithm with factor analysis and a local search optimization system for pattern identification problems as applied to large and multivariate aero-geophysical data. The algorithm was developed in MATLAB code using both multivariate and univariate methodologies. Two main analysis steps are detailed in the MATLAB code: the first deals with multivariate factor analysis to reduce the problem of dimension, and to orient the variables in an independent and orthogonal structure; and the second with the application of a novel local research optimization system based on univariate structure. The process of local search is simple and consistent because it solves a multivariate problem by summing up univariate and independent problems. Thus, it can reduce computational time and render the efficiency of estimates independent of the data bank. The aero-geophysical data include the results of the magnetometric and gammaspectrometric (TC, K, Th, and U channels) surveys for the Santa Maria region (RS, Brazil). After the classification, when the observations are superimposed on the regional map, one can see that data belonging to the same subspace appear closer to each other revealing some physical law governing area pattern distribution. The analysis of variance for the original variables as functions of the subspaces obtained results in different mean behaviors for all the variables. This result shows that the use of factor transformation captures the discriminative capacity of the original variables. The proposed algorithm for multivariate factor analysis and the local search system open up new challenges in aero-geophysical data handling and processing techniques.

ÍNDICE DE VULNERABILIDADE DAS ÁGUAS SUBTERRÂNEAS NO MUNICÍPIO DE ROSÁRIO DO SUL, RIO GRANDE DO SUL.

This research is part of integration award of instruments, and collection guidelines for the management of groundwater Project. The objective of this work was to study the groundwater vulnerability of the Rosario do Sul city, in Rio Grande do Sul state, southern Brazil on the edge of the Parana Basin. It is part of the outcrops zone (ZA) Guarani Aquifer System (GAS). This aquifer is porous, unconfined, intergranular, unconfined belonging to Piramboia Formation. Was estimated the aquifer pollution vulnerability index map using the GOD methodology adapted to Brazilian conditions. Were developed a database of 35 tubular wells associated with the hydrogeological characteristics of the overlying vadose zone necessary to use. Was considered groundwater hydraulic confinement, overlying strata and the depth to groundwater table. The range of the vulnerability Index was High (40.00%), followed Moderate (28.57%), Low (14.29%), Extreme (14.29% ) and Negligible (2.85%) from the total studied area. Key-words: vulnerability, GAS, GOD, aquifer. ERTEL et al., v(7), no 7, p. 1400-1408, MAR-AGO, 2012. Rev. Elet. em Gestao, Educacao e Tecnologia Ambiental (e-ISSN: 2236-1170) http://cascavel.ufsm.br/revistas/ojs-2.2.2/index.php/reget/index 1401

CHARACTERIZATION OF HYDROGEOCHEMICAL PROCESSES IN GROUNDWATER OF SANTA MARIA AQUIFER SYSTEM, IN THE CENTRAL REGION OF RIO GRANDE DO SUL

A study was carried out of the hydrogeochemical processes involving the groundwater of the western portion of the Santa Maria Aquifer System (SMAS) in the central region of Rio Grande do Sul. The objective of this study was to characterize the behavior of a portion of the groundwater between Sao Pedro do Sul, Santa Maria and Restinga Seca municipalities, based on a model between water/rock interaction. Mineralogical and hydrochemical information were analyzed, aiming to model the hydrogeochemical evolution of the aquifer in these municipalities. For this purpose, a processing of the information in a geochemical modeling code was performed, using as previous reference mineralogical studies. The results pointed out the main geochemical interactions responsible for groundwater chemistry, which is strongly dependent of the chemical composition of the recharge waters and the mineralogical contribution of the sedimentary rocks of this aquifer system. The groundwater saturation states showed subsaturation processes tending to the balance of carbonate minerals, indicating the dissolution of these minerals, mainly calcite, as well as supersaturation of clay-minerals ilite, montmorillonite (smectite) and kaolinite, in both cases tending to the alkalinization of the environment. The characterization of the hydrogeochemical properties of aquifers is important for a correct understanding of the processes that occur in it and dominate the regional hydrogeology.

Previsão de Níveis Estáticos de Água Subterrânea em Poço de Monitoramento Utilizando Metodologia Estocástica

O presente estudo busca modelar e analisar o comportamento natural de uma serie temporal de nivel estatico de agua subterrânea e precipitacao com o intuito de fazer previsoes dos niveis para um horizonte de 6 meses. Para tanto, aplicou-se um modelo estocastico da classe ARMA (autorregressivo e de medias moveis) em dados semanais de nivel estatico de agua subterrânea e precipitacao. O ambiente geologico do poco estudado e caracterizado por formacoes sedimentares da borda da Bacia do Parana, localizado no municipio de Alegrete no Estado do Rio Grande do Sul. O poco de monitoramento e dotado de registrador automatico de nivel onde o espaco temporal considerado foi de pouco mais de 2 anos de medicoes sem falhas. Testaram-se modelos autorregressivos e de medias moveis ate a terceira ordem de autocorrelacao. Selecionou-se o melhor modelo com base nos valores de AIC (Akaike Information Criterion) e BIC (Bayesian Information Criterion), onde escolheu-se o ARMA (2, 0) o qual obteve o melhor ajuste. A analise de erros permitiu observar o bom desempenho da modelagem a partir do grafico de residuos normalizados, atestando a qualidade preditiva do modelo escolhido. A avaliacao dos coeficientes do modelo permitiu estabelecer uma relacao em milimetros aproximada de 0,31:1 para as variaveis nivel estatico e precipitacao respectivamente.

Superfície potenciométrica e possíveis fontes de contaminação do aquífero parecis no município de Vilhena - RO,BR

The control and preservation of groundwater quality are the main tasks to be performed during environmental planning of this resource. Thus, the present study aims to determine the lines of groundwater flow in the municipality of Vilhena, Amazon Region. This town gets its water supply from the Parecis Aquifer. Potencial sources of contamination were identified including gas stations, municipal cemetery, contaminated supply wells and inactive dumps. Through the potentiometric surface map was determined a vulnerability of the well number 27 which is the responsibility of the Autonomous Service for Water and Sewage, which is located in an area of ​​convergence of flows, and thus can receive contaminant loads coming from the municipal cemetery and two inactive dumps. Thus, the study of the potentiometric surface of the Parecis Aquifer is a valuable tool for spatialization of Geographical Information System that allows, by observing the generated map, locate the best spots for installation of new supply wells, gas stations, providing subsidies for management process, land use and control the exploitation of groundwater at the municipal level.

CARACTERIZAÇÃO HIDROQUÍMICA E VULNERABILIDADE NATURAL À CONTAMINAÇÃO DAS ÁGUAS SUBTERRÂNEAS NO MUNICÍPIO DE AMETISTA DO SUL- RS

Groundwater generally have better natural condition than surface water. However, because of lithological diversity, they present variable chemical composition, which can also be modified by contaminant loads. This study aimed to evaluate the hydrochemistry, the natural vulnerability of aquifers to contamination and the potentiometric surface of the Serra Geral Aquifer in the municipality of Ametista do Sul, RS. The data was obtained from the Groundwater Information System. There was selected eleven captures information with electrical conductivity, pH, sodium, potassium, calcium, magnesium, chloride, carbonate, bicarbonate, sulfate, fluoride, total alkalinity, static level profiles geological and geographical coordinates. From the Qualigraf 1.1 program, there were generated Piper diagrams for chemical classification and diagrams Stiff and Schoeller-Berkaloff to check the tendency of water. The vulnerability was determined from the GOD system. The pH was between 7.4 and 10.2. As for the chemical classification, ten samples showed up with sodium bicarbonate and sodium as mixed. Five samples showed fluoride concentrations greater than the Maximum Allowed 1.5 mg L-1 established by the Ministry of Health and the natural vulnerability of the aquifer to contamination ranged from insignificant to low.

ESTIMATIVA DA VULNERABILIDADE NATURAL À CONTAMINAÇÃO DO AQUÍFERO NO MUNICÍPIO DE SÃO SEPÉ- RS

As a result of the significant increase in urbanization and the need to supply the population service increase gradually grows the use of groundwater to meet different uses.Based on this, the studies of the aquifer vulnerability to contamination becomes an important tool. This study aims to map the vulnerability of groundwater in Sao Sepe- Rio Grande do Sul, southern Brazil, which is located in the Uruguayan South Rio-Grandense shield, fractured crystalline aquifer. For the spatialization the method used was GOD, adapted to the Brazilian conditions. Then, a hydrogeological database was elaborated for the eight funding containing the necessary information for the method (degree of containment, middle aquifer and deep water level). The vulnerability cartogram pointed out the predominant class such as low, equivalent to 44,56 % of the total area, followed by the middle class represented by 39,33% and the high class with 12,91% mapped. The extreme and insignificant classes represented 2,78 % and 0,42 % respectively. These results highlight the need for vulnerability indices, which should be considered for the licensing of potentially polluting enterprises and implementation of master plans.

AQUIFER POLLUTION VULNERABILITY OF THE SANTA MARIA WATERSHED, RIO GRANDE DO SUL STATE, BRAZIL

With the increasing pollution of surface water resources, groundwater consumption has grown rapidly in recent times. It is a resource that most often does not require treatment for human consumption. From this, there are some tools that aim to assist in the management of those groundwater resources. This paper aims to evaluate the natural vulnerability of aquifer to contamination in the watershed of the Santa Maria River, within the Parana Sedimentary basin in the Rio Grande do Sul State, southern Brazil. The GOD scheme was applied to determine the aquifer pollution vulnerability. Results indicate a moderate vulnerability for ca. 31.89% of the area, and a high vulnerability for 50.44% of the total area. These natural characteristics were related with the predominance of porous/permeable sandstones in its substrate constitution and the occurrence of shallow groundwater levels. This geologic context makes the aquifer more vulnerable according to GOD scheme. These results are important for the management of groundwater resources, uses in municipal master plans and land use.

Variabilidade de Parâmetros Físico e Químico na Coluna de Água em Poços Tubulares Locados na Zona de Afloramentos do Sistema Aquífero Guarani

O Campus da Universidade Federal de Santa Maria (UFSM) e abastecido principalmente por aguas subterrâneas, sendo essas captadas em Zona de Afloramentos (ZA) do Sistema Aquifero Guarani (SAG). O presente estudo tem por objetivo analisar duas variaveis, uma fisica que e a temperatura e uma quimica que e a Condutividade Eletrica (CE) na coluna da agua em dois pocos tubulares dedicados a pesquisa no Campus da UFSM. Estatisticamente, nas duas datas distintas de coletas, os dados apresentaram bastante uniformidade, sendo que a CE caracteriza pelo incremento do seu valor na medida em que se desce na coluna da agua e a temperatura tente a decair a medida que se aprofunda na coluna da agua. Houve algumas pequenas variacoes entre as diferentes datas de coleta para os mesmos pocos, contudo constatou-se que prevaleceu a uniformidade dos dados na maioria dos casos.