Letter to the editor: Kamloops This Week (05 September 2013)
Mr. Yves Lacasse in his letter of 21 August on behalf of KGHM International gives lip service to concerns of the citizens but provides no details, no data, no specifics regarding how the potential problems will be prevented before they occur. People don't want a phone number to call after there is a serious health problem. They do want damage to the ecosystems and human health to be avoided in the first place. Let's consider an actual number, from the mine's own sub-contractor (Stantec). They say 16 g s-1 (grams per second) of PM2.5 (particulate matter less than 2.5 micrometers in diameter) would be emitted in their "worst-case" scenario.
This "worst-case" emission rate of PM2.5 for a day will occur in the 14th year of mine operations. It's a model calculation, of course, with unknown accuracy, but let's take it at face value and see what it means. The Total Particulate Matter produced is estimated to be 6 times more than this but let's look only at the PM2.5. These are the fine particles in the air that will get deep into the human respiratory (breathing) system. The study was sent by Stantec to the BC EAO (British Columbia Environmental Assessment Office) on 08 May 2013 (http://a100.gov.bc.ca/appsdata/epic/html/deploy/epic_document_362_35719.html).
Actually 16 g s-1 of PM2.5 doesn't sound like a lot of fine particles, but air quality guidelines don't deal with grams per second of emissions. The British Columbia objective for PM2.5 is 25 ug m-3 (25 micrograms per cubic meter of air) for a 24-hour period and 8 ug m-3 as an annual average. The planning goal is 6 ug m-3 as an annual average. This goal cannot presently be met even without the mine in operation. What is relevant is that 16 g s-1 is 1.4 million million micrograms per day. That's a lot.
To compare this emission rate to the BC air quality objective, we have to put the PM2.5 into a volume of air. If we assume a layer 10 m deep, 8 km long, and moving at 2 m s-1 all day long over the mine site, the concentration of PM2.5 in the air passing through the mine site's boundary would be about 100 ug m-3. This air would move into the city with both the prevailing winds and the mountain drainage winds. Along the southern boundary of the city, this would be 4 times the BC PM2.5 objective of 25 ug m-3. Therefore, using the mine's own number for worst-case emissions of PM2.5 and some simple arithmetic, we see that there could easily be a huge negative impact on air quality in the city. Other assumptions can be made about emission rates and about the winds and the air entering the city but clearly the impact on air quality in Kamloops will not be zero.
Each microgram of material added to our air is important because each microgram can be composed of up to one hundred billion individual particles. These go into our respiratory system and depending on their sizes, shapes and chemical composition, have been documented to cause a wide range of health problems (see www.kphe.ca). Using just one number from the mine's own documents shows that their sales pitch about ‘zero harm' is marketing but not reality.
Dr. Robert Schemenauer, Ph.D. (Atmospheric Physics)