Probabilistic risk assessment of nitrate groundwater contamination from greenhouses in Albenga plain (Liguria, Italy) using lysimeters.

The use of fertilizers in greenhouse-grown crops can pose a threat to groundwater quality and, consequently, to human beings and subterranean ecosystem, where intensive farming produces pollutants leaching. Albenga plain (Liguria, Italy) is an alluvial area of about 45km historically devoted to farming. Recently the crops have evolved to greenhouses horticulture and floriculture production.

Analytical Solutions of Three-Dimensional Contaminant Transport Models with Exponential Source Decay.

Despite the availability of numerical models, interest in analytical solutions of multidimensional advection-dispersion systems remains high. Such models are commonly used for performing Tier I risk analysis and are embedded in many regulatory frameworks dealing with groundwater contamination. In this work, we develop a closed-form solution of the three-dimensional advection-dispersion equation with exponential source decay, first-order reaction, and retardation, and present an approach based on some ease of use diagrams to compare it with the integral open form solution and with earlier versions of the closed-form solution.

Assessment of sediment contamination and sampling design in Savona Harbour, Italy.

A method for assessing environmental contamination in harbour sediments and designing the forthcoming monitoring activities in enlarged coastal ecosystems is proposed herein. The method is based on coupling principal component analysis of previous sampling campaigns with a discrete optimisation of a value for money function. The objective function represents the utility derived for every sum of money spent in sampling and chemical analysis.

A new method for laboratory estimation of the transverse dispersion coefficient.

We introduce a method for identifying the transverse dispersion coefficient in laboratory experiments based on the analytical solution of a pulse injection of a nonreactive solute in a soil column (cylindrical geometry) packed with a homogeneous porous medium. This method takes into account the effect of boundary conditions such as no flux on the column perimeter, and it does not need a priori knowledge of the longitudinal dispersion coefficient. Numerical applications of the method show that it is stable and robust and that the results are reasonably in accordance with those found using the classical maximum likelihood method.