The state of Pará has the largest deposits of metallurgical bauxite in Brazil, with emphasis
on the western regions (municipalities of Oriximiná and Juruti, with two mines in operation)
and Northeast regions of the state (municipalities of Paragominas – one mine in operation – and
Rondon do Pará). The lateritic/bauxitic cover of the bauxite province of Paragominas is a
product of extreme weathering of siliciclastic sedimentary rocks and is composed of minerals
resulting from the highest degree of alteration, that is, kaolinite (Al2Si2O5 (OH)4), gibbsite
(Al(OH) )3 , goethite (FeOOH), hematite (Fe2O3) and anatase (TiO2), to which are added
traces of relict quartz, traces of heavily degraded mica and heavy minerals of greater resistance
in humid tropical conditions such as rutile (TiO2), tourmaline and zircon (ZrSiO4). In addition
to the extraction of bauxite, its mineral transformation, which takes place in the industrial
district of Barcarena, near Belém, with the Hydro-Alunorte Alumina refinery, and the
production of metallic aluminum by Albras. Due to recent events related to the disposal of waste
in decantation basins (DRS) used by the mining company, a climate of distrust on the part of
public opinion regarding the safety of the mining populations that live in the vicinity of the
company, especially regarding the issue of human health, since the constitution of residues from
the mineral transformation of the ore is not completely known. The objective of this research is
to determine the presence and study the geochemical behavior of trace elements such as U, Th
and ETR, in addition to other heavy metals, such as Hg, Cd and Pb, in bauxites and lateritic
covers from the Miltônia mine, in Paragominas, and residues (red muds) from Barcarena, the
relationship with the accessory mineralogy of these materials and establishment of reference or
background values for environmental assessment. The present work was carried out with
samples from 1 bauxite profile (section HIJ-231), located in the Miltônia 3 mine, collected
through drilling holes and/or from the mine front, process samples were also collected from the
SAG mill of the plant I, separated into different granulometric fractions, supplied by Norsk
Hydro. The XRD and XRF analytical processes were carried out at the Mineral Characterization
Laboratory (LCM) from UFPA, while the Scanning Electronic Microscopy stage was carried
out at the Microanalysis Laboratory of same Unit/Institution. The results of chemical and
mineralogical analyzes of samples from the Miltônia 3 mine, both raw bauxite and its
granulometric fractions, after autogenous milling, showed a relationship between the high
values of ZrO2 and TiO2 verified and the accessory minerals - zircon, rutile and anatase.
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