Environmental management of quarries as waste disposal facilities

Landscape Project for the Environmental Recovery of a Quarry

The growth of urban populations causes cities, and their suburbs, to spread, expand, and replace natural lands by agricultural. Urbanization brings land-use change, altering the relationship between human societies and environmental resources. Therefore, the management of natural resources connected to urban expansion has become one of the most important challenges in attaining sustainable landscape. Quarrying is a crucial component of local socio-economic development providing key materials for infrastructures and buildings. However, like many other human activities, quarrying causes a significant impact on the environment. In Mediterranean countries, quarrying activities exert increasing pressures on limited soil and water resources, thus accelerating erosion processes and subsequent destruction of existing arable lands. Quarrying operations can profoundly alter pre-existing ecosystems and perturb hydro-geological and hydrological regimes. They can profoundly modify the substratum, change landscape patterns and integrity, destroy natural habitats and interrupt their natural succession, as well as alter genetic resources. The resulting situation is seriously compromised by anthropic regeneration processes on degraded sites after the end of quarrying activities, which are not focused on potential natural vegetation which these sites could develop, considering the surrounding ecosystems. In this work, we propose a landscape regeneration project which was developed as part of the Environmental Impact Assessment procedure on quarrying activity located in the municipality of Lecce, South Italy. This project aims to integrate environmental and landscape aspects with the economic and social ones in order to guarantee the sustainability of the proposed intervention. The new project modifies the one presented at the start of the quarrying activity which planned planting of trees directly on the bottom of the quarry, (about 40 meters deep from the ground level and three meters above the groundwater level). The new project foresees the partial filling of the quarry using waste materials according to the environmental legislation. This allows to protect the groundwater better and to create a microclimate more suited to the development of natural vegetation. The quarry filling activity represents an economic activity for the company and therefore can guarantee the development of jobs for at least 5 years. In addition, the proposed project aims to reconstitute the pre-existing vegetation, consistently with the surrounding ecosystem. This will allow the development of the priority habitat *6220: Pseudo-steppe with grasses and annuals of the Thero-Brachypodietea (Directive 92/43/CEE), producing a landscape of recognized ecological value, not detached from the surrounding landscape. In this way, the closed quarry can act as a stepping stone and play a significant role in regulating green infrastructure in landscapes.

Using GIS and optimization to manage construction and demolition waste: The case of abandoned quarries in Lebanon

Increased stress on raw material and limited landfill space due to increasing rates of urbanization have encouraged efforts to divert Construction and Demolition Waste (C&DW) away from landfills toward sorting, recycling, and reusing. While these efforts have been successful in some countries (e.g., Germany, Netherlands), developing countries tend to suffer from illegal and haphazard dumping of C&DW. This study presents an optimization based decision support tool to select a cost and environmentally effective set of abandoned quarries to serve as C&DW landfills and processing facilities. The tool is composed of a GIS model and a mixed integer linear program that accounts for the complete waste management chain. A case study in Lebanon served as a testbed for the tool: A multi-criteria analysis was first used in GIS to evaluate the environmental suitability of candidate quarries based on five thematic groups: socio-economic, topography, geology, hydrology and infrastructure. The most suitable quarries were then inputted to the optimization model. Two out of 148 abandoned quarries in Mount Lebanon were deemed suitable for rehabilitation under the objectives set yielding a profit of 125 million US dollars over a 20 year span. Future challenges include enhancing the model by incorporating time and accounting for more recycling technologies.

Detection and Geometrical Characterization of a Buried Landfill Site by Integrating Land Use Historical Analysis, Digital Photogrammetry and Airborne Lidar Data

Abandoned quarries are frequently used as sites of illegal dumping of solid urban waste. These sites often occur nearby or within urban areas so that their detection may turn out to be quite difficult from the surface. This study focuses on the detection and geometrical characterization of a hidden landfill site located along the coastline of the Campi Flegrei, near Naples, Italy. Our approach is based on the analysis of historical topographic maps and aerial photographs, coupled with quantitative comparison of multitemporal digital elevation models obtained by digital photogrammetry and lidar techniques. The comparative analysis of topographic maps and aerial photos clearly shows modifications of the landscape associated with the urban development and quarrying activity, as well as the later filling of the quarry. The change detection analysis reveals that remarkable elevation changes occurred in the study area between 1956 and 2008. The average thickness of the landfill deposits is ca. 8 m, whereas the average volume is ca. 100,000 m3. The results of this work confirm the suitability of the used methodological approach that combines both qualitative and quantitative techniques for the detection of buried landfill sites. The geometric characterization of a landfill represents a fitting starting point for the further planning of geophysical site surveys and direct investigations aimed at the assessment of environmental hazards.

Analyzing tree cores to detect petroleum hydrocarbon-contaminated groundwater at a former landfill site in the community of Happy Valley-Goose Bay, eastern Canadian subarctic

This research examines the feasibility of analyzing tree cores to detect benzene, toluene, ethylbenzene, and m, p, o-xylene (BTEX) compounds and methyl tertiary-butyl ether (MTBE) in groundwater in eastern Canada subarctic environments, using a former landfill site in the remote community of Happy Valley-Goose Bay, Labrador. Petroleum hydrocarbon contamination at the landfill site is the result of environmentally unsound pre-1990s disposal of households and industrial solid wastes. Tree cores were taken from trembling aspen, black spruce, and white birch and analyzed by headspace-gas chromatography-mass spectrometry. BTEX compounds were detected in tree cores, corroborating known groundwater contamination. A zone of anomalously high concentrations of total BTEX constituents was identified and recommended for monitoring by groundwater wells. Tree cores collected outside the landfill site at a local control area suggest the migration of contaminants off-site. Tree species exhibit different concentrations of BTEX constituents, indicating selective uptake and accumulation. Toluene in wood exhibited the highest concentrations, which may also be due to endogenous production. Meanwhile, MTBE was not found in the tree cores and is considered to be absent in the groundwater. The results demonstrate that tree-core analysis can be useful for detecting anomalous concentrations of petroleum hydrocarbons, such as BTEX compounds, in subarctic sites with shallow unconfined aquifers and permeable soils. This method can therefore aid in the proper management of contamination during landfill operations and after site closures.

Identification of quarries rehabilitation scenarios: a case study within the metropolitan area of Bari (Italy)

This paper addresses quarries rehabilitation issue within a Metropolitan Area. Areas where mining activity is carried out have been subjected to physical and environmental degradation linked both to pursue the building materials extraction and to the city expansion continuously asking for new areas to be developed with residential and service functions. These changes also occurred where environmental and landscape values are present. It has been therefore pointed out the issue of such areas redevelopment that, to be functionally reintegrated, must be consistently linked to the activities and the territorial local contexts characteristics. In this paper the quarries reuse issue is carried out through parameters identification able to define the quarries relationship with the neighboring towns and with their surroundings besides to identify their physical, environmental and landscaping characteristics. Quarry reuse alternatives have been identified among those consistent with the rehabilitation goals, as defined by the planning sector and internationally approved, while their selection is derived from the application of a two-step methodology: a multi-criteria analysis related to punctual parameters at a "site-specific" level, followed by a further territorial indicators checking over the wide area. This application has led to socially accepted results identifying the examined quarries for reuses ranging from agricultural-forestry and urban to functional or naturalistic. The proposed method has also proved to be suitable to address the abandoned quarries reuse problem with a systemic and consultative approach, as it is able to correlate the many variables present in the social and spatial complexity of the Metropolitan Areas.