This project takes place in OHMI Estarreja in Portugal, at Geosciences Department and Mechanics Engineering Department (Aveiro University). The aim of this presentation is to recognise some differences with other research lines, contiguities and some innovation relating with environmental monitoring. In a classic case of environmental monitoring, (e.g. in abandoned mining areas), with some mineralogical and chemical complexity of primary parageneses with sulphides and also of secondary parageneses with sulphates and arsenates, an environmental research includes the monitoring of water and bottom sediments in rivers, (affected by mine drainage, or not), and establishing seasonal monitoring sites throughout months or years, in a planned timeline. Some parameters could be determined in situ, but the general ones could be done by lab analysis. Also in this case it could be established the regional chemical content, the anomalies, the dispersal vectors of contaminants - establishing the classic monitoring system, cross-cutting or transversal studies. Extending the method (and the budget) we can cover larger areas, but we will reduce scales and sampling density. The output is the geochemical distribution maps, with high spatial illustration, but not considering the change of the environment and their dynamics. The monitoring system we are beginning to develop is different from the conventional system, and it is only possible because it takes place in a high environmental contrast area, with several scientific and technical references, since the 1970s. This area, which is in contiguity with the estuarine environment (Ria de Aveiro) has a strong industrial, agricultural and human pressure, a great hydrodynamics, with a dense fluvial drainage and inter-tidal influence. The main physico-chemical changes in the environment are related either to salinity or to human impact generated over the decades from the Chemical Complex of Estarreja (CQE). The most significant anomalies concerned the arsenic content (associated with waste treatment) and the mercury content (that includes reagents and by-products of chemical industries, used from the 1950s until the 1990s.). In this first phase of the postdoc we are selecting significant locations to measure continuously those critical (direct and indirect) parameters - attending to the large number of scientific publications, technical reports, evaluation and control programs. Comparing the Portuguese regional research with the European Geochemical Atlas (both transversal approaches) we can see a clear difference of detail. OHMI ESTARREJA promotes the study of complex phenomena in the field of natural and applied sciences, where our team represents Hydrogeochemistry combined with Mechanical Engineering to develop ENVIRONMENTAL LONGITUDINAL ANALYSIS. Several studies have highlighted the flows and biogeochemical cycles of the heavy metals, and most especially mercury - the complexity of which have been recognized in multiple transfer vectors, at the ecosystem level. The scientific data-bases - the OHM enhritage - can be taken as references to the longitudinal studies. They incompense diversified sampling media, with different sampling grid and reflecting a wide variety of interface phenomena, like: reactivity, chemical exchange and transfer in the trophic food chain. Specifically relating with sampling media we should indicate studies with soil, water, sediment, fauna and flora and,recently, dust, whose scientific papers relate study areas more or less extended. Regarding the sampling grid studied, with points or collection wells, rivers, estuaries, larger or smaller areas with different grid cells densities, these are associated with a sampling frequency for periods not exceeding five years. Still, the research in surface phenomena recognise more expression correlating sampling media, namely: water-soil; dissolved-soluble fractions, water-biota; water-microbiota, inthis last case associating applied studies in agriculture, health, specially regarding pregnancy. Thus, it is revealed the dynamic nature of the environment, the most influential variables and distribution models, both in biogeochemical relations, also ecological and the impact within all environment and society. It is important to develop longitudinal studies - with retrospective base, descriptive, prospective, predictive (or control) extending the period of analysis the parameters measured, and the frenquency/ refreshing rate. This allows us to determine daily cycles and also tidal cycles, changes in weather patterns and, still, the industrial operations cycles and theire effluent discharges. The study that we are currently developing, different from the other, is innovative, regarding: - the in situ analysis of critical parameters (direct and / or indirect); - the (multi)parametric measurement in continuum for over a month, with high frequency, less than a minute and with energy and equipment being autonomatly calibrated; - the transmission in real time, with a network system, and monitoring remotely the response (WSN).