African Journal of Agricultural Research Vol. 7(23), pp. 3429-3432, 19 June, 2012 Available online at http://www.academicjournals.org/AJAR DOI: 10.5897/AJAR11.2061 ISSN 1991-637X ©2012 Academic Journals Full Length Research Paper Impact of extractive industry on an agricultural soil in San Luis Potosí, México Juan Carlos Rodríguez Ortiz 1 , Jorge Alonso Alcalá Jáuregui 1 *, Catarina Loredo Osti 1 , Humberto Rodríguez Fuentes 2 , J. Jesús Tapia Goné 1 and Alejandra Hernández Montoya 1 1 Faculty of Agronomy, Autonomous University of San Luis Potosi, Km 14.5 Carr, San Luis-Matehuala, Soledad de Graciano Sánchez, S.L.P. México. 2 Faculty of Agronomy, Autonomous University of Nuevo León, Km 7.5 Carr.Zuazua-Marín, Marín, N. L. México. Accepted 3 May, 2012 This case study arose from the opening of an ordinary civil trial, brought by a farmer against a company in the extractive industry sector. The judge required an investigation of: 1) whether the plot of the producer contained waste materials; 2) if there were chemical residues present; 3) the nature of such residues; 4) whether the plot was suitable for agriculture; 5) what were the factors which made the soil unsuitable; and 6) the degree of erosion. 65% (1.63 ha) of the property was affected by industrial spills, mainly due to the high proportion of gravel at the surface (90%), calcium carbonate equivalent (62%), reduction of organic matter (1.85 to 1.25%) and excessive erosion (19.44 t ha -1 ). The rest of the plot (0.87 ha) was not affected by these parameters. Both sites were not affected as regards heavy metals and metalloids pollution, abnormal pH and electrical conductivity. Key words: Heavy metals, calcium carbonate, gravel. INTRODUCTION The main activity of the mining industry is the exploitation and processing of rock materials, clay, sand and other natural resources. The state of San Luis Potosi, Mexico, has been characterized since its foundation as a major producer of materials both metallic and nonmetallic, which in 2010 reached a combined production value of around $ 957.8 million. Due to the economic importance of this industry and the production potential of the organization, expectations of further growth are very high (Secretary of Economy, 2011). However, several studies have shown that some extraction projects can significantly impact the environ- ment. This damage can be of two types: 1) the impact of the depletion of nonrenewable resources for future generations; and 2) the impact of mining on the quality of the environment through air, soil, water, or noise pollution, destruction or disturbance of natural habitats, and visual impact on the landscape (Stacishin et al., *Corresponding author. E-mail: jorge.alcala@uaslp.mx. Tel/ Fax: 444 8 52 40 56. 2008).The latter problem has been documented by several studies in Mexico and Latin America (Rea, 2001; García et al., 2007; McDonalds, 2009). This case study arises from the opening of an ordinary civil trial, brought by a farmer against a company in the extractive industry sector (mainly a producer of limestone), which produces 25 000 t day -1 (Secretary of Economy, 2011). The producer, said to have been affected by the deposition of mineral materials in the plot (2.5 ha) from the year 2002, now finds himself unable to produce consumption commodities such as maize and beans. In 2009, the judge of civil branch office requested to investigate the following: 1) Whether the plot contained waste materials, 2) If such materials were chemical wastes, 3) The nature of any material and chemical contaminants, 4) Whether the plot was suitable for agriculture, 5) What factors, if any, made the plot unsuitable for agriculture? 6) The degree of soil erosion.