Stone, Sand & Gravel: Gravel Facts
As you travel through Ontario you've likely passed an operating quarry or gravel pit without even knowing it; there may even be one in your community. Some people think that pits and quarries are unnecessary. But stone, sand and gravel are vital to our daily lives. Explore this website and uncover the facts. Contrary to what you may have heard, the aggregate industry sources aggregate in the most responsible way possible, protecting water and wildlife. And we're the only industry that can return land to nature, agriculture or recreational uses.
Water Management in Quarries
The aggregate industry is sophisticated, accountable and deeply committed to environmental stewardship.
Aggregate producers are primarily water handlers and not consumers. The actual amount of water consumed at an aggregate operation is relatively small. Well over 90% of the water handled is returned to the local watershed. The handling and use of water in an aggregate operation is regulated by multiple legislative requirements which require, among other things, the submission of detailed scientific studies prior to any approval being granted. Therefore private well users are fully protected under legislative authority. Once extraction at a quarry is completed, the site is rehabilitated creating water assets and enhancing the naturalenvironment in ways that help mitigate the local impacts of climate change.
Read more about why the public can be confident about water management in the aggregate industry.
Water Use in Pits and Quarries
Aggregate operators are primarily water managers, and not water consumers.
To understand how water is managed, it helps to understand that pits and quarries come in three major categories, and each uses water a bit differently.
The first category, representing the majority of sites, is where sand, gravel and rocks are extracted from above the water table, so the operations do not reach far down enough to have any impact on the water table. With these operations, water is used to wash fine particles from the extracted gravel or stone, and then the water is recycled in a closed-loop system and used over and over again. Very little water is lost.
The second category of sites is where sand and gravel is dredged from below the water table. In these types of operations the water stays where it is, only the sand and gravel is removed. Years of monitoring these operations have shown no impact to the water table.
The third kind of operation is a rock quarry. In this case, the water may have to be pumped out of the quarry so that blasting and digging can be done safely. However, water is not consumed in the operation, but discharged onto the surrounding surface where it filters back into the ground or is sent to nearby rivers or lakes.
Quarries that operate below the water table are required by law to mitigate impacts to nearby sensitive features such as wells, streams and wetlands. Once extraction is complete, these sites become lakes or new important wetlands.
Protecting People and the Environment
The aggregate industry is one of the cleanest, and most highly regulated industries in Ontario, to ensure the protection of people and the natural environment. The 25 pieces of legislation that protect the environment and future resources include regulations set out by the Ontario Ministry of the Environment and Climate Change, Ontario Endangered Species Act, the Greenbelt, Oakridges Moraine and Niagara Escarpment Plans as well as the Aggregate Resources Act.
Often, producers will go beyond what is required by law to protect wildlife - such as creating buffer zones near sensitive natural resource areas, working closely with local conservation authorities on environmental management projects, and sponsoring environmental research and protection efforts.
No chemicals are involved in the extraction or processing of aggregate materials. The topsoil, and other organic mateiral removed from the rock surface before mining begins is not sent to a landfill or used for other landfill purposes, it is stored on-site and used in the rehabilitation of the pit or quarry site.
What happens to former pits and quarries?
Progressive and final rehabilitation (turning former aggregate sites into new uses) is a legal requirement for producers of aggregate. What that means is that once the material from an active area of a site has been removed, producers must rehabilitate the site in accordance with the site plans that they submitted to receive their aggregate licence. And likewise, when the final section of the site has been extracted, the producer is required to complete any rehabilitation that remains.
OSSGA members frequently go above and beyond the requirements in their site plans and actively work with community partners to create exceptional new land uses for their former sites. Between 2010 and 2014, researchers from OSSGA visited and assessed the condition of a total of 701 pits and quarries across southern and eastern Ontario that were licensed, rehabilitated, and surrendered under the Aggregate Resources Act (1990) or the Pits and Quarries Control Act (1971). What did they find? The most common land uses for rehabilitated aggregate sites are:
- Natural (25%)
- Agriculture (21%)
- Open Space (15%)
- Water (10%)
For examples of outstanding rehabilitation, visit our Bronze Plaque award winners!