Environmental assessment and reclamation of abandoned marl mining dumps in the Northwest Caucasus

Abstract

This paper discusses the assessment of the environmental impact of marl mining dumps within the industrial agglomeration of Novorossiysk city (Northwest Caucasus, Russia). It presents methods for the ecological and geochemical assessment of terrestrial and aquatic landscapes of the urban landscape and briefly describes field investigations, laboratory tests and statistical data processing used in the assessment. A technique for improving the ecological hazard estimation reliability for mine dumps was developed. It includes identification of poly-element geochemical anomalies and calculation of integral indicators for soil pollution and legacy contamination in the city, as well as the eco-risk of the probability of debris-flow occurrence at the dumps. The paper proposes a method for reducing the ecological hazard of the dumps in the agglomeration. The method is based on the analysis of modern approaches to landscape revitalisation and compares possible ways to stabilise the soil cover of the dumps. The proposed technical reclamation uses a geosynthetic cover and biological reclamation through hydro-seeding of a mixture containing soil amendments, understory and grass and selected woody plant species to reduce erosion. The results were accepted for implementation by the research-production and supervisory organisations of the city of Novorossiysk, and confirmed by three certificates. The technical proposals for abatement of the technogenic hazards and their impacts on the environment, developed in the course of research, can be used to improve the ecological situation within the urban areas of Novorossiysk. The proposed solutions for environmental protection may be used by mining enterprises that also generate waste dumps requiring reclamation to limit deflation and erosion and prevent pollution and debris flows.