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BC Politics

Hydro Officials Quietly Feared Fracking Threat to Peace River Dams

FOI reveals Crown corp’s behind-the-scenes negotations for a buffer zone around projects.

Ben Parfitt 16 Aug

Ben Parfitt is a resource policy analyst with the Canadian Centre for Policy Alternatives – BC Office and author of Fracking Up Our Water, Hydro Power and Climate: BC’s Reckless Pursuit of Shale Gas, a research report published in 2011 that called for frack-free zones.

Senior BC Hydro officials have quietly feared for years that earthquakes triggered by energy industry fracking operations could damage its Peace River dams and put hundreds – if not thousands – of people at risk.

Yet the Crown corporation has said nothing publicly about its concerns, opting to negotiate behind the scenes with the provincial energy industry regulator, the BC Oil and Gas Commission (OGC).

Those discussions have resulted only in modest “understandings” between BC Hydro and the commission that would halt the issuing of any new subsurface rights that allow companies to drill and frack for natural gas within five kilometres of the Peace River’s two existing dams or the controversial $9-billion Site C dam.

Companies already holding such rights, however, would not be subject to the ban.

But once again, none of this is public knowledge. Only after the Canadian Centre for Policy Alternatives filed a freedom of information request did BC Hydro disclose its concerns, which focus on the possibility that fracking could trigger earthquakes more powerful than some of its dams are designed to withstand.

Documents released by the Crown corporation show that in December 2009 Hydro senior officials became alarmed at oil and gas industry operations near its Peace Canyon Dam. The dam is 23 kilometres downstream from the W.A.C. Bennett Dam, a 49-year-old structure that impounds the world’s seventh-largest hydro reservoir.

Hydro officials were concerned about an experiment to extract methane gas from coal seams near the Peace River. Coal bed methane extraction had never been tried in B.C., although it had been used extensively in several U.S. states and Alberta, sometimes with disastrous results, including instances of contamination so serious people could set their tap water on fire.

To extract such gas, companies drill into relatively shallow coal seams and pump immense amounts of water under high pressure into the wells. Fracking creates cracks or fractures in the coal seams that allow trapped gas to be released. Typically, companies then pump the water out so the gas can flow.

Hydro’s concern was sparked by the activities of Hudson’s Hope Gas, a subsidiary of Canada Energy Partners and GeoMet Inc. The company had drilled at least eight coal bed methane wells near Hudson’s Hope, which is about nine kilometres downstream of the Peace Canyon Dam and home to more than 1,000 people.

Fracking an ‘immediate threat,’ warned Hydro safety chief

The company had plans to drill and frack up to 300 wells, with at least three close to the Peace Canyon Dam.

The plans alarmed Ray Stewart, BC Hydro’s chief safety, health and environment officer at the time, who called them an “immediate” threat to the region’s hydro facilities.

“The production of coal bed methane from these wells involves hydro-fracturing to increase permeability of the coal seams, followed by extraction of groundwater to de-saturate coal seams and allow methane gas to be released,” Stewart noted in a letter to the Ministry of Environment’s Glen Davidson, then British Columbia’s comptroller of water rights.

“BC Hydro believes that there are immediate and future potential risks to BC Hydro’s reservoir, dam and power generation infrastructure as a result of this.”

Stewart warned that the “potential effects” could include industry-induced earthquakes that were more powerful “than the original design criteria for the dam.” Stewart did not say what risks this posed to downstream people and communities.

Stewart also warned fracking could “reactivate” ancient faults, potentially leading to earthquakes. And he cited the risk of unspecified “hydrogeologic impacts” on reservoirs and the potential for land to subside, either as a result of immense amounts of water being pumped out of the earth or if de-watered coal seams somehow ignited.

There are no further such letters from Stewart in the documents supplied by BC Hydro. Part of the reason may be that coal bed methane extraction was a short-lived phenomenon in B.C. No company is currently drilling or fracking for such gas in the province.

However, no sooner had natural gas companies dropped their pursuit of coal bed methane than they turned to another “unconventional” fossil fuel – shale gas.

The Montney Basin, which underlies much of the Peace River region, is rich in shale gas. But extracting shale gas, which is tightly bound up in rock formations, requires the use of even greater brute force fracking technology. More water must be pumped at even higher pressure to fracture the rock and extract the trapped gas, which is typically found deeper than coal bed methane.

Fort St. John fracking site
A fracking site seen from the air near Fort St. John, BC. Photo by Jeremy Sean Williams, Wilderness Committee.

As fracking for shale gas became more common, senior officials at BC Hydro began to see a pattern. Earthquakes started occurring in lockstep with fracking operations.

One of the clearest examples was in the Farrell Creek fracking zone, near BC Hydro’s Peace River dams. Between July 2010 and March 2013, a dozen earthquakes were recorded in the region, ranging from a low of 1.6 magnitude to a high of 3.4.

The cluster of earthquakes, all in roughly the same region where one company, Talisman Energy, was involved in extensive fracking operations, caught the attention of Scott Gilliss, BC Hydro’s dam safety engineer in the Peace River region.

Gilliss made his concerns known to senior officials at head office. Shortly after, he received an email from Des Hartford, Hydro’s principal engineering scientist, who reported directly to Stephen Rigbey, the corporation’s director of dam safety.

“Scott,” Hartford’s email began. “As was discussed at the Department Meeting yesterday, this is to confirm that having brought forward your concerns about hydraulic fracturing (‘fracking’) activities in proximity of dams and reservoirs, you have discharged your responsibilities with respect to reporting and management of this matter. It is now up to Stephen as advised by me to determine what if any action should be taken by Dam Safety with respect to this matter.”

“Fundamentally, hydraulic fracturing (‘fracking’) is one of these ‘new and emergent’ threats that require examination in the context of scientific and policy considerations in order that any meaningful management actions can be initiated if required,” Hartford continued.

Hartford instructed Gilliss to document his concerns so others at BC Hydro could “take them forward.”

Lessons from a California disaster

Gilliss did so, pointing out in a subsequent email released under the FOI request that “oil and gas production may have contributed to a dam breach” at the Baldwin Hill Dam in Los Angeles in 1963.

The Baldwin Hill breach, as described by award-winning investigative reporter and Tyee contributor Andrew Nikiforuk in his most recent book, Slick Water, occurred at a then new dam. It resulted in a “colossal rupture that sent 292 million gallons of water spilling into a residential community, destroying hundreds of homes and killing five people.”

A review of the catastrophe by Richard Meehan, an expert on fluid migration at Stanford University, and Douglas Hamilton, a prominent civil engineer, concluded that “fluid injection” by the oil and gas industry, combined with sinking ground around the dam, had led to the structure’s sudden and deadly failure.

“This is the case study that triggered my concern over hydraulic fracturing in the Peace,” Gilliss wrote in an email to Hartford on March 17, 2013. “The Baldwin hills case appeared to have occurred following very intense [oil and gas industry] exploration and development, the likes of which we don’t have here yet. The geology of their site was also quite complex and riddled with faults. A similarity does exist in that there are two small thrust faults downstream of PCN [the Peace Canyon Dam] which dip beneath the dam. Reactivation of these small faults could be problematic for PCN. There are other north south trending fault[s] in the area.”

Gilliss ended his letter on a note of exasperation.

“In my view, which I have already shared, the province should simply add buffer zones around any very Extreme and Very High Consequence Dams, where hydraulic fracturing cannot be undertaken without a prior full investigation into the risks, and an implemented risk management plan. Why is this so difficult?”

Gilliss’s buffer zone idea wasn’t new. Two years earlier, after conducting research for the Canadian Centre for Policy Alternatives, I wrote a report calling for “no-go zones” where fracking was prohibited to protect other important resources such as water. By then, there were also de facto bans on fracking in Quebec and New York State.

Gilliss and other top BC Hydro officials soon had even more reason to think that no-go zones made sense. More and more earthquakes in northeast B.C. were being triggered by fracking, including a magnitude 4.6 tremor that occurred north of Fort St. John last year. That earthquake was in an area being fracked by Progress Energy, a subsidiary of Malaysian state-owned Petronas. It was the largest in the world linked to fracking operations.

Petronas is behind a controversial proposal to build a massive liquefied natural gas terminal at Lelu Island near Prince Rupert. The raw gas for the LNG plant would come almost entirely from northeast B.C., including the Peace River area, and would be produced by fracking.

At least some of that gas would come from lands adjacent to what could one day be a new 83-kilometre-long reservoir impounded by the Site C dam. Like the upstream Bennett dam, Site C would be an earth-filled dam.

The Bennett dam, completed in 1967, is now almost exactly halfway through its projected 100-year operating life. At almost two kilometres across and the height of a 60-storey building, it is one of the largest earth-filled dams in North America.

In 1996, it became the subject of intense engineering and safety scrutiny when two sinkholes suddenly opened at the crest of the dam.

In a magazine article written three years later, writer Anne Mullens noted that a dam failure would unleash a torrent of water so powerful that it would wipe out the Peace Canyon Dam downstream, sending an “unstoppable burst of water 135 metres high” down on the residents of Hudson’s Hope and communities much farther downstream.

“Unlike a tsunami, the destruction wouldn’t simply peak and stop,” Mullens wrote in BC Business. “The pent-up waters of Williston Lake would just keep coming, seeking to return to its natural elevation. The waters would flow for weeks, scouring away communities like Old Fort, Taylor, Peace River, Fort Smith and beyond. The onslaught would back up tributaries and inundate the entire Peace River Basin, flooding Lake Athabasca and Great Slave Lake. The floods could devastate northern Alberta, portions of Saskatchewan and the Northwest Territories all the way to the Arctic Ocean. The death toll could be high; the environmental and structural damage astronomical. Combined with the loss of generating power of the dam, the unprecedented disaster would cost billions of dollars and throw B.C.’s economy into turmoil.”

Fracking damage potentially costly: Hydro

Stephen Rigbey, BC Hydro’s director of dam safety, says that in the aftermath of the discovery and repair of those sinkholes the Bennett dam has become “one of the world’s most studied and instrumented dams.”

In an interview following the release of the FOI materials, Rigbey said Gilliss and other dam safety officials operating in the field are paid to worry.

Rigbey said he has no concerns that fracking operations would trigger a catastrophic failure at BC Hydro’s Peace River dams.

But Rigbey did say that ground motions from fracking operations could cause slight alterations to “weak bedrock” near the dams and that in turn could change the way that water naturally seeps through earth-filled dams. Ground motions could also knock some electrical control equipment offline, Rigbey added.

If either happened, BC Hydro would be faced with high repair and maintenance costs.

“Would it [fracking] bring the dam down? Not a hope. Would it do damage and cost me a lot of money? Absolutely. It would cost me a lot of time and a lot of money and that’s what I don’t want to occur,” Rigbey said.

Rigbey said that’s why BC Hydro has sought to exclude fracking from zones near the Bennett and Peace Canyon dams and around the construction zone of the Site C dam.

The current unwritten “understanding” between the OGC and BC Hydro is that no new tenures will be awarded to companies allowing them access to natural gas deposits in a zone within five kilometres of the three dam sites.

Companies already holding such rights will, however, be allowed to drill and frack for gas. In the event that happens, BC Hydro says it will work with the OGC “to effectively manage any risk.”

“This is a work in progress,” Rigbey said. “We are working toward strengthening the current understanding.”

Graham Currie, the Oil and Gas Commission’s executive director of corporate affairs, confirmed the five-kilometre buffer zones in an emailed response to questions. He said the buffer zone around Site C will “prevent the sale of oil and gas rights within the buffer area.”

Currie added that the proposed Site C dam falls within the Montney shale gas zone, one of the most actively drilled and fracked zones in the province.

“Site C falls within the Montney play and will be built to a high seismic safety standard,” Currie wrote. “During construction, permit conditions on a well in the Montney may be used to control the timing of hydraulic fracturing operations. All wells in the Montney are double-lined with cement and steel to a depth of 600 metres for further protection.”

The email does not mention that such protective measures do not prevent fracking-induced earthquakes. Cement casings, which are often imperfectly poured and prone to fail, are intended to prevent groundwater from being contaminated – a different issue.

The “understanding” between BC Hydro and the OGC applies only to the dams and not the lands around the reservoirs themselves, Currie said.

That includes lands around what could one day be the Site C reservoir, which could experience up to 4,000 landslides as the reservoir fills and after, according to a document prepared for BC Hydro. Whether fracking could further destabilize those lands, damaging the reservoir and dam itself, remains unknown.

What is known, however, is that earthquakes induced by fracking behave entirely differently than naturally occurring earthquakes.

Gail Atkinson is a professor in earth sciences and leading expert on the effects of induced earthquakes who holds the Industrial Chair in Hazards from Induced Seismicity at the University of Western Ontario. The chair is funded, in part, by TransAlta, a privately owned electricity provider in Alberta.

In response to written questions, Atkinson said most people would agree with the proposition that “precluding oil and gas activity such as fracking... within some radius of dams and reservoirs would prevent the possibility of induced seismicity that could damage such facilities.”

Atkinson said the big concern with earthquakes triggered by events such as fracking is that they occur much closer to the earth’s surface than natural earthquakes. A fracking-induced tremor might be as close to the surface as two kilometres, while a natural earthquake might occur 10 kilometres down.

The shaking caused by a fracking-induced earthquake may be short, but it is a stronger and different kind of shaking. The potentially “strong ground motions” generated by such shaking occur “closer to infrastructure on the surface.”

“The concern is that the potential for induced earthquakes to generate strong motions makes it difficult to satisfy the high safety requirements for critical infrastructure, if earthquakes can be induced by operations in very close proximity [to dams and reservoirs],” Atkinson said.

While there is “no consensus” about what constitutes a reasonable size for no-frack zones, buffer zones do make sense, Atkinson said.

“A zone of monitoring beyond the buffer zone is also a good precautionary measure in my view, as it would allow low-level induced seismicity from disposal or fracking beyond the buffer to be detected quickly and any necessary measures to be taken,” Atkinson said. “Enhanced monitoring would also provide valuable research data to improve our understanding of the issue.”

In a telephone interview, Hydro’s Rigbey said he agreed that both firm no-fracking buffer zones and wider special management zones made sense.

Atkinson’s thinking is consistent with TransAlta’s efforts to protect some of its hydro facilities in Alberta from fracking operations. Those efforts appear to have effectively shut down fracking in a buffer zone around one of TransAlta’s dams and the dam’s reservoir. Special operating guidelines are also in place beyond the buffer zones that can force companies to cease fracking.

But, as is the case in B.C., negotiations between TransAlta and Alberta’s energy industry regulator have happened behind closed doors.

Members of the public at direct risk should a catastrophic dam failure occur are kept in the dark when it comes to negotiations that could have a direct impact on their lives.

Tomorrow: Alberta’s advances and questions about why B.C. may be lagging.  [Tyee]

Read more: Energy, BC Politics

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