Testes de bombeamento e com traçador para determinar confinamento e parâmetros hidráulicos do aquífero alter do chão em Manaus-Am

Abstract

The Alter do Chão Aquifer (AAC), in northern Brazil, has large dimensions and very high water potential. In Manaus, the AAC water reserve is estimated at 14,4 km3

. Because it is easily accessible and has good water quality, this aquifer supplies approximately 40% of the city's population. Projections indicate that there are around 27.000 wells in Manaus, most of which do not have proper registration or construction control. For proper management of the AAC, it is necessary to have detailed knowledge of its hydraulic properties and the movement of solutes in the different layers of this aquifer. The first part of this work was carried out in the Nova Cidade neighborhood, in Manaus, where the degree of confinement of the pumped layer was obtained, transmissivity 1.66x10-3 ,

storage coefficient 1.19x10-2

, hydraulic conductivity 9.76x10- 6, hydraulic conductivity 1.04x10-6 and relationship between vertical and horizontal (or radial) hydraulic conductivity in the aquifer of 5.69x10-2

, through the interpretation and spatialization of data from the constant flow pumping test. The second stage of this manuscript was carried out in the Underground Hydraulic Test Field, located on the South Campus of the Federal University of Amazonas, where pumping and tracer tests were carried out, through which the degree of confinement in intermediate layers of the AAC was determined, transmissivity 8.0x10-4

, storage coefficient 5.4x10-5

, hydraulic conductivity 3.1x10-5 , effective porosity 9.9%, longitudinal dispersivity 1.2 meters, retardation coefficient 1.2, real mean water velocity underground 1.3x10-5

and urine decay constant 1.3x10-6 .