The Do Not Consume (DNC) order that has been in place for a 70km stretch of the Thompson River west of Ashcroft since January 13 has been downgraded to a Water Quality Advisory (WQA) as of February 16.
The DNC order was put in place by Interior Health (IH) following a CP derailment seven kilometres west of Ashcroft on January 12. Twenty-nine rail cars carrying metallurgic coal derailed, and although no cars entered the river, between 120 and 160 tonnes of coal were spilled into the Thompson and onto the bank above it.
Dan Ferguson, manager of environmental health for IH, said in late January that they had hoped to be able to downgrade the DNC order to a Water Quality Advisory. Water testing sites were set up at the site of the derailment, as well as up- and downstream from it, and samples were sent to the Ministry of the Environment to be tested.
While the samples tested negative for hydrocarbons or other contaminants, it was determined that more samples would need to be tested for the presence of seven newly identified potential residues that could be linked to the coal. While coal is non-toxic, metallurgic coal is treated with chemicals before being heated and dried.
Ferguson says that a Water Quality Advisory is the lowest of four water advisories IH issues. “It means there’s something different in the water system, and we believe it to be low risk, but we want to let people know.”
The next level is a Boil Water notice, which is only used if there are microbiological elements in the river; it would not be used in the case of possible chemical contamination, as boiling the water would not remove chemicals, which is why the derailment initially triggered the third level of warning, the DNC order. “It means we don’t want you to drink it,” says Ferguson, “either because there’s a gross microbiological contamination or the water has been contaminated by chemicals.”
The highest warning level is Do Not Use, which means the water is only fit to use for flushing toilets.
“The warning [for the Thompson] has gone from level three to level one,” says Ferguson. The WQA will remain in effect until environmental cleaning efforts by CP are completed. This requires either safe removal of all the spilled coal from the incident site, or a determination that the remaining coal at the spill site poses no risk.
Remediation work is still ongoing, and there is no projected completion date. Ferguson notes that as far as he can determine, the main users of the stretch of the Thompson River affected by the WQA, between the derailment site and the confluence with the Fraser River at Lytton, do so for agricultural purposes (Spences Bridge does not draw its water from the Thompson).
The cause of the derailment has not been determined, and the Transportation Safety Board (TSB), which is in charge of the incident, says that it could take up to a year to complete the investigation.
James Carmichael, who is in charge of the investigation, says that any derailment investigation focuses on three areas.
“When we do an investigation, we look into how the train was being handled, we look at all the mechanical aspects of the locomotives and the rail cars themselves, and of course we look into the infrastructure of the track itself,” he says.
A TSB investigation into the cause of a collision between two CP trains near Golden in September 2015 did not reach its conclusion until January 2017.