A Uranium Mine(s) and Mill in West Quebec - A Scenario

Many people I've been in touch with about uranium exploration, mining and milling in West Quebec believe it is important for people to be aware of what a uranium mine(s) and mill might be like. Admitedly it is not possible to predict with precision what might come to pass, but based on experiences elsewhere, it is possible to paint a picture, via a scenario, of what might be involved. Variations on the scenario are possible and likely, but a scenario serves to illustrate key aspects of a mining and milling operation.

Introduction

Uranium mining and milling operations typically involve putting the infrastructure in place to build and support the mine, the operation of the ore extraction process, the milling of the ore and the decommissioning and long-term management of the defunct mine/mill site.

Infrastructure

The infrastructure required for a mine or mill depends in part on the size of the operation and what infrastructure is already available. Common requirements include: roads for transport of all materials and equipment in and out of the site(s); electricity and fuel for equipment; water for the extraction process; chemicals for the milling; storage of the waste water and tailings; and site facilities and equipment.

Depending on how good the roads are leading to and from the mine site, upgrades may be required. In remote areas sometimes this means adding a new road(s) when one did not exist. These roads must be sufficient to carry all of the equipment and materials to and from the mine and mill site. This means the heavy equipment (e.g., very large digging tools and trucks), fuel, chemicals and supplies. The roads may also be needed to transport ore from the site once it is mined. It is usually more economical for the mining company to actually process (mill) the ore at or near the mine site to reduce the costs of trucking the ore to a more distant location for processing.

Site materials and equipment can usually be brought in and removed fairly easily, although structures and equipment that are not saleable at the end of the mining stage are typically left behind and buried with the tailings.

The Mine(s)

A mine is typically operated for around 10 to 15 years (although some may only operate for a year or two, and others can operate for 30 years or more). Generally speaking, the smaller the ore deposit, and the closer its proximity to the surface, the shorter the lifespan of the mine.

According to media reports, open pit mines (as opposed to deep mines or in situ mines) would be the most likely type to be developed in West Quebec, due to the geology of the Canadian Shield. This is because the ore is not that deep, it is spread out and is not in sandstone-like rock that would enable leaching of uranium to take place by pumping leaching chemicals underground and extracting uranium back up.

Open pit mines cover a sizable area and create large cavernous holes in the earth.

Given the loation of the mining claims in the West Quebec region, statements by exploration companies and media reports, and where the prospecting has taken place, is taking place or is planned to take place, there could conceivably be at least four mine sites in the lower Outaouais alone. One is near Fort-Coulonge, another near Shawville, another on Grand-Calumet Island and another is around East Aldfield. Other sites are also possible in this area, and there are several other locations further afield being claimed and explored.

Caution: none of these sites has been chosen for a mine, and it is also quite possible none of them ever will be. Before any of them could be developed an environmental assessment would have to take place. A potential mine(s) is years in the making. Remember, this is a scenario only.

Here are some pictures of open pit uranium mine sites:
http://www.flickr.com/photos/hhs/119819594/
http://www.grahamdefense.org/Images/key-lake.jpg
http://geoscape.nrcan.gc.ca/nsask/images/basin7.jpg

Water Resources

Water is used extensively in the uranium extraction and milling processes. It is mixed with both the raw rock and crushed rock to control dust and to mix with chemicals to help release (leach) uranium from surrounding material. This leads to large amounts of waste water ("liquor") that must be disposed of, often by evaporation followed by the burial of the remaining solid residues (tailings). Water is taken from the ground or from a nearby lake. In some cases, a lake must be drained because the uranium deposit is beneath it. A lake bed could potentially become a tailings site.

This link shows a picture of a tailings pond:
http://www.wise-uranium.org/img/quirkea.jpg

Milling (Chemical Processing)

As noted, a uranium mill is needed to leach uranium out of the ore taken from the ground. Once the rock has been extracted from the ground it must be crushed to a fine sand-like consistency. Once crushed, the milling can occure. A mill is a chemical processing plant. Chemicals used to leach ore in the milling process include suphuric acid (most commonly) or alkalines (less commonly). The leaching agent extracts uranium and other ingredients such as molybdenum, vanadium, selenium, iron, lead and arsenic.

Here are some pictures of uranium mill sites:
http://www.saskmining.ca/image/photoLib/uranium/uranium08.jpg
http://www.wma-minelife.com/uranium/mill/graphics/ccdc.jpg

Tailings

Given it typically takes about a tonne of rock to produce one or two pounds of uranium, the residual tailings are very consequential in volume. Tailings are typically stored at the mill site and left there once the mining is complete. They contain typically 85% of the radioactive content of the mine site and the radioactivity does not completely subside for many thousands of years. Both radioactive particles and radon gas emanate from the tailings due to a complex chemical decomposition of the tailings over time. These tailings are typically submerged under water in the short term, and are later buried at or near the extraction site under clay and rock for perpetuity (to prevent gamma radiation and radon gas from migrating from the mill site). The largest mines can produce as much as 30 million tonnes of solid waste material.

This link shows a picture of a tailings site:
http://moab-utah.com/rack/atlasm.html

Yellow Cake

The uranium residue ("yellow cake") is packed in containers and removed from the site of the mill for even further processing elsewhere.

Here is what "yellow cake" looks like: http://i.timeinc.net/time/covers/1101030721/popup/images/uranium.jpg

Long-term, Post-Mining and Milling Site Management

Once the mine(s) and mill has ceased operations, the long-term management of the site(s) begins. The open pit has to be restored, leftover chemicals and fuels have to be removed or buried, and the tailings have to be contained for posterity. Buildings and equipment have to be removed and the area may need to be closed off for safety reasons. Monitoring is required to make sure there are no leaks or spills of tailings.

Here are some pictures of mine sites after production has ended:
http://www.flickr.com/photos/tabletwo/3979644/
http://www.ucd.ie/kyr/Umine.jpg
http://deseretnews.com/dn/view/0,1249,595048748,00.html