Early last year, an army of workers at a remote natural gas operation in northern British Columbia set a world record for hydraulic fracturing or “fracking,” a procedure that is rapidly becoming the norm in the global gas industry.

They pumped nearly 400 Olympic swimming pools worth of water along with 500,000 kilograms of sand underground to fracture deeply buried shale rock, thereby releasing its trapped gas.

As fracking becomes more common, people living in natural gas-rich northeast BC are increasingly alarmed over the associated public health and safety risks.

The pressure at which water, sand and undisclosed chemicals is pumped belowground is so intense that it triggers tiny earthquakes. In using such brute force, unforeseen and unwelcome problems can — and do — surface elsewhere, problems that may include dangerous releases of gas containing hydrogen sulphide, also known as sour gas.

Long before fracking arrived on the scene, the health threats posed by chronic exposure to sour gas with low levels of hydrogen sulphide were well known and ran the gamut from irritated eyes to miscarriages. But it was the uncontrolled releases of gas containing 300 parts per million or more of hydrogen sulphide that filled people living in BC’s Peace River region with dread. Such releases killed or seriously injured industry workers; caused deaths, birth defects or miscarriages in cattle; forced people to abandon their homes by dead of night; and led at least one school district to station buses outside an elementary school in case sour gas escaped from a nearby well site, forcing an emergency evacuation.

These and other uncomfortable realities of living in the heart of BC’s natural gas development zone recently prompted a local citizens group — the Peace Environment and Safety Trustees Society (PESTS) — to call upon the provincial government to launch a formal inquiry under BC’s Health Act to delve into the health risks associated with sour gas. The justification for such an inquiry was laid out in chilling detail with the assistance of Calvin Sandborn, at the University of Victoria’s Environmental Law Clinic, and Tim Thielmann, an environmental lawyer.

The initiative has since snowballed. Letters of support for an inquiry have come from the Peace River Regional District, public health officers, First Nations and others. A common refrain in the correspondence is that when it comes to key decisions on oil and gas industry activities — for example, the locating of gas wells and pipelines that can release toxic gas — public health officials are cut out of the loop. Yet it is they, and the public they serve, who are forced to respond when things go wrong.

Things most decidedly did go wrong in November 2009, when failed piping at a gas well in the Peace region spewed 30,000 cubic metres of gas into the air. Hydrogen sulphide levels in the escaping gas were six times above lethal levels. The estimated eight-hour gas leak forced the evacuation of 18 residents living near the community of Pouce Coupe, killed a horse and resulted in at least one emergency hospitalization.

BC’s Oil and Gas Commission (OGC), which approved the well owned by Encana Corporation, later concluded that frack sand corroded the pipes and caused the potentially fatal leak.

Over the past three decades, at least 34 workers in BC and Alberta have been killed in sour-gas related incidents and hundreds more disabled. By sheer luck, massive uncontrolled sour gas releases in BC have often occurred far away from local communities. In 2003, residents near Gao Qiao, Chonquing, China weren’t so lucky. A sour gas leak there forced the evacuation of 64,000 residents and killed 243 people in what became a 25 square kilometre death zone.

Escalating fracking activities increase the likelihood of such leaks. As a recent OGC “safety advisory” notes, high-pressure fracking operations have on at least 18 occasions resulted in what are euphemistically called “communications” between northern BC gas wells.

What this means is that fracking at one well causes unwanted problems at another. In one such event, the same type of corrosive frack sand linked to the Pouce Coupe disaster was blown between two gas wells spaced 670 metres apart.

Under the circumstances, members of the Peace Environment and Safety Trustees Society should be lauded for being “pests.” By highlighting the public health and safety risks associated with sour gas, they may force the provincial government to do the right thing: call an inquiry that is clearly in the public interest, but most particularly in the interests of the women, children and men who call the Peace River region home.

Ben Parfitt is a resource policy analyst with the BC office of the Canadian Centre for Policy Alternatives and author of Fracture Lines: Will Canada’s Water be Protected in the Rush to Develop Shale Gas?, a report for the Program on Water Issues at the Munk School of Global Affairs.