Salvadora Martínez-López

Importance of the oral arsenic bioaccessibility factor for characterising the risk associated with soil ingestion in a mining-influenced zone

Arsenic is a carcinogenic metalloid and the risks of accidental ingestion should therefore be borne in mind when assessing areas with high levels of this element. In this work, the concentrations of bioaccessible As in mining-influenced soils, in SE Spain are determined. The risk posed by the accidental ingestion is studied in two soil fractions (<2mm and <250μm), taking into consideration the possible uses of the soils (residential/agricultural) and possible receptors (adults and/or children). The properties and mineralogical composition of 26 soil samples are analysed. The results showed that the use of a conservative approach to calculate the Chemical Daily Intake (CDI) based on the total concentrations of arsenic, may overestimate the risk existing in the zone, leading to problems in the management of contaminated soils. The paper emphasises the importance of considering the amount of bioaccessible As in the <250μm fraction before permitting land near temporary watercourses to be used for residential purposes, as beaches or for agriculture.

Proposals for the Remediation of Soils Affected by Mining Activities in Southeast Spain

Abstract The zones affected by long-term mining activities are currently of special interest since they represent a contamination focus influencing large areas. These particular sites are usually abbreviated as CAMAs (critical abandoned mining areas). Sierra Minera of Cartagena-La Union is a CAMA with an interesting and valuable ecosystem that needs adequate management tools. Suitable management should be based on the results of a risk assessment procedure, based on proximity to populations or the use that a specific space may have. The risk assessment needs to consider human health and/or ecosystems. The most serious concern in this respect is the behavior and fate of potentially toxic elements such as lead, cadmium, zinc and arsenic, which were present in the raw materials and may be bioavailable. Remediation measures would be based on the natural attenuation of impacts that have occurred in this area and would include neutralization of the acid mine drainage, increase of the natural vegetation favoring the growth of tolerant species (even with low transference factors), and gully regulation in order to avoid spills on crops or at sea.

Ecoefficient In Situ Technologies for the Remediation of Sites Affected by Old Mining Activities: The Case of Portman Bay

Abstract A review of the historical events that caused a serious environmental impact in a zone affected by mining activities was carried out. Portman Bay, located in southeast Spain, is one of the greatest points of mining-metallurgical contamination of the Mediterranean Sea. After an intense mining exploitation, starting in Roman times, the activity ended in 1991, with more than 60 MT of steriles filling the bay. The decision to recover the bay started in 2007, and studies characterizing and analyzing the risks of materials in surface and depth were carried out. At the same time, a pilot project was designed with two experimental areas using Technosols as an in situ recuperation technology, considering both urban and residential use. In addition, an experimental center for the optimization of proposed technology was constructed, and different analyses, such as marine ecotoxicity techniques or artificial wetland experiences, were carried out. Currently the environmental recovery work is being carried out by the Spanish Ministry of Agriculture, Food and Environment.