Problems of ground water in connection with abandoned open pit mines

Abstract

Mining is an essential activity upon which many other industries rely on immensely. The magnitude of the problem caused by abandoned mines in the time to come can be understood from the topographic maps prepared using remote sensing applications and field studies in Athurugiriya, Gonapola and Kaduwela areas of the Colombo district. Mahara harbour quarry and the Ragama prison quarry, two abandoned metal quarries were studied with reference to the prevailing conditions of the water quality and the ground water regime. Geological investigations were conducted at the site to identify possible linkages of the pit with the surrounding ground water regime. By analysing the water samples for physical, chemical and biological parameters, the quality of the water was studied .Results show severe pollution in pit water as well as in surrounding round water. The harbour quarry has maintained it's purity due to the efforts and care taken by its stakeholders and neighbours, The continuously degrading quality of the environment at the prison quarry site makes its neighbours affected as well as accused for the problem. The study further shows that in addition to the water quality studies, socio environmental factors should be further studied in order to provide a sustainable solution to the prevailing environmental pollution problems related to abandoned open pit mines in and around Colombo district.