Limestone is an important resource for building renovation and restoration, and a key component in industrial processing. However, the impact of limestone quarrying on the environment and on human health makes for sobering reading. Weighing up the pros and cons pits the importance of profit and the built environment against environmental degradation and the health and well-being of quarry workers and local people.
Historical restoration of limestone buildings relies heavily on quarried limestone. Many councils and heritage organisations insist that buildings be restored "like for like" to retain their authenticity and that original limestone paving be replaced with similar stone. The War Memorials Trust, for instance, will neither replace limestone panels with anything other than limestone, nor use mortars based on anything other than the original lime.
Building and Agricultural Materials
Lime plays a massive part in the building trade and in farming. Ground limestone is an essential component of Portland cement for concrete, a material in abundant use across the globe, and tons of limestone aggregate form the bases of roads, housing and other construction projects. Agricultural lime, or aglime, is added to soil, where it complements the action of fertilisers and herbicides and aids drainage, as well as preventing erosion and countering soil acidity.
Manufacturing and Industrial Processes
Limestone is an essential component in iron smelting, as well as an effective filter in a wide range of applications, including air purification technologies to remove sulphur dioxide and hydrogen chloride, domestic and industrial water treatment systems and agribusiness. It is a key component in sugar production and refining, and limestone's alkaline properties are used to balance pH in waste and drainage.
A consensus exists among environmentalists, academics and the public that limestone quarrying leads to soil erosion, landslips and sinkholes, damage to water courses, risks of flooding due to dramatic changes in water levels, and the destruction of beautiful landscapes.
Loss of Wildlife Habitats
A report on the East Asian and Pacific environment reveals losses and extinctions of indigenous species of insects, animals and trees that depend on limestone-specific habitats. The delicate balance that exists between the land and the life it supports is fatally skewed. Globally, researchers also find that limestone quarrying is destructive to cultural and historical evidence of previous civilisations, evidence which informs future scientific, environmental and cultural development.
In many countries, the negative impact on workers in limestone quarries and neighbouring communities has been partly offset by stringent health and safety regulations. However, where health and safety monitoring are not so tightly regulated, as in Colombia and Zambia, for example, workers are not well protected, and succumb to pneumoconiosis and silicosis from inhaled dust. Noise and dust pollution from blasting, quarrying and increased traffic levels impact heavily on wildlife and on neighbouring communities.