MONITORING GROUNDWATER CHEMICAL COMPOSITION AT A EXPERIMENTAL AREA IRRIGATED WITH PETROLEUM PRODUCED WATER
AbstractAgricultural reuse of the produced water is an efficient means for water resource management. However it is a potentially impacting activity to soil and groundwater, and thus requires environmental monitoring throughout the process. From this perspective, the present work aims at the monitoring of groundwater quality of karstic aquifer, located in the northeast of Brazil, where an irrigation experiment was carried out using PW of the Fazenda Belém oil field, in Ceará State, Brazil. Twelve monitoring wells were evaluated through a four-stage sampling program: the first before the installation of the irrigation experiment (CHA) and the other three, respectively, during (MO1), immediately at the end (MO2) and after the experiment (MO3). The climatic effect was also considered in the evaluation, since sampling events occurred in distinct seasonal periods: the first and the last at the end of the dry season and the second and third at the end of the wet season. Investigations were performed considering two groups of wells: upstream wells and downstream wells in relation to groundwater flow in the experimental area. For Ca2+, Mg2+, K+, total hardness, HCO3-, F-, As, B, Li and P, there was a tendency of increasing concentrations in the Monitoring sampling, in relation to CHA. However, since this scenario was verified in both sets of wells (upstream and downstream), its causes are probably related to natural factors. It was also observed that highest concentrations occur predominantly in the MO1 and MO2 sampling stages, that is, under the influence of the wet season, when water recharges promote dissolution of carbonate constituents present in the aquifer, thus increasing its dissolved concentration. Organic substances analyzed in groundwater were not detected or were detected at very low and dispersed concentrations and without any source specific signatures. Hence, their origin can be attributed to natural or diffuse inputs.
The copyright to this article is transferred to Sociedade Brasileira de Geoquímica effective if and when the article is accepted for publication. The author(s) warrant(s) that his/her/their contribution is original and that he/she/they has/have full power to make this grant. The author(s) sign(s) for and accept(s) responsibility for releasing this material The copyright transfer covers the exclusive right and license to reproduce, publish, distribute and archive the article in all forms and media of expression now known or developed in the future, including reprints, translations, photographic reproductions, electronic form (offline, online) or any other reproductions of similar nature.
Author(s) may self-archive an author-created version of his/her/their article on his/her/their own website and or in his/her/their institutional repository. He/she/they may also deposit this version on his/her/their funder’s or funder’s designated repository at the funder’s request or as a result of a legal obligation, provided it is not made publicly available until 12 months after official publication. Author(s) may not use the publisher’s PDF version, which is posted on www.geobrasiliensis.com.br, in repositories. Furthermore, the author(s) may only post his/her/their version provided acknowledgement is given to the original source of publication, assigning the link where it can be found. This link must be accompanied by the following text: “The final publication is available at www.geobrasiliensis.com.br”.
The author(s) retain(s) the right to use his/her/their article for his/her/their further scientific career by including the final article published by Geochimica Brasiliensis in other publications such as dissertations, theses and postdoctoral qualifications provided acknowledgement is given to the original source of publication.
After submission of the agreement signed by the corresponding author(s), changes of authorship or in the order of the authors listed will not be accepted by Sociedade Brasileira de Geoquímica.
Title of article:
Place and Date: