[Flash Walken]

Originally Posted by Bring_Back_Shantz

Okay, the way this statement is worded makes me want to point out to anyone who may be reading it, that Daradon should not be taken as any source of truth on this particular topic.

Speaking about the way natural gas is "Mined" and how it "pors out, basically in gas form" followed by "as I understand it" is a pretty clear indication that while parts of what he is saying are technically accurate, he does not in fact understand it.

That being said, as for leakage, and monitoring, methane is ~30 times more potent than CO2 as a greenhouse gas, but considering it produces 50% less CO2 than coal, then we'd have to have a 3-4% leak rate to balance that out. Trust me, at least here in Alberta, we'd know if we were leaking anywhere near that ammount. Beyond that, there are regulations about monitoring for leaks, and it is done, most companies going well beyond what they are required to do.

It certainly isn't perfect, no fuel is, but natural gas has some pretty large advantages over coal, not just from a CO2 emissions standpoint, but also with respect to other envirionmenal impacts (Again, it's not perfect and comes with it's own set of challenges).

A new University of Waterloo report warns that natural gas seeping from 500,000 wellbores represent "a threat to environment and public safety" due to groundwater contamination, greenhouse gas emissions and explosion risks wherever methane collects in unvented buildings and spaces.

The 69-page report on wellbore leakage cowritten by three expert UofW professors outlines a longstanding and largely invisible engineering problem for Canada's oil and gas industry.

It also calls for dramatic reforms in monitoring and regulation including greater engineering oversight of the cementing of wellbores and "doing it right in the first place."

The scale of the problem? Ten per cent of all active and suspended gas wells in British Columbia now leak methane.

In addition, some hydraulically fractured shale gas wells in that province have become super methane emitters that spew as much as 2,000 kilograms of methane a year.

That amount of methane would make an audible hiss at the wellbore or form a big bubble in a swamp, says report lead author Maurice Dusseault, one of nation's top petroleum engineers.

An average wellbore may leak about 100 kilograms of methane a year, or the same as cow, but little data has been collected or accurately verified.

In Saskatchewan, about 20 per cent of all energy wells leak. In Alberta, regulators report chronic seepage from 27,000 wells.

Twenty years ago, the heavy oil fields of Lloydminster reported a leakage rate as high as 46 per cent. A 2010 industry study noted that the failure rate for steam injection wells for bitumen production approached 30 per cent.

...

Methane leakage from wellbores, pipelines, pumps and urban gas distribution systems have become a hot button issue because they can undermine or reverse the greenhouse gas advantage that natural gas has over coal or oil.

A natural gas field that seeps three to four per cent of its product can be a more aggressive forcer of climate destabilization than coal and therefore dirtier, say a growing number of scientists.

That's because methane is a much more powerful greenhouse gas than carbon dioxide over a 20-year time frame.

Due to its potent climate effect, methane leakage from thousands of wellbores will ultimately become "a federal issue," warns Dusseault, who recently made presentations to the Alberta Energy Regulator on the scale of the problem.

"The Americans are going to get us moving on this issue," adds Dusseault, citing U.S. President Barack Obama's recent decision to reduce climate change emissions from power plants by 30 per cent.

Ignoring the problem or shooting the messenger will just erode the industry's social license to operate, warns Dusseault. "I think the industry has to be more pro-active and should get in front of this issue."

Awareness 'exploded'

The problem has existed for decades, but industry and regulators have largely ignored the liability until climate science changed its profile along with an unconventional drilling boom that added tens of thousands of wells to the North American landscape.

Fourteen years ago, when Dusseault first wrote about the subject in a scientific paper titled "Why Oilwells Leak," he got no mail. "But now the public awareness has exploded."

Together with engineer Richard E. Jackson, a co-writer of the recent report, Dusseault has been making non-stop presentations.

Each and every wellbore that punctures the earth potentially becomes a man-made superhighway for methane and other gases such as radon that would normally take millions of years to migrate to the surface.

If not cemented and sealed properly, stray gas will travel from deep or intermediate zones and migrate along the casing to the atmosphere, surface waters or into aquifers.

The shattering or hydraulic fracturing of rock formations, which often result in fractures jumping out of targeted oil and gas zones, can also provide additional pathways for methane seepage.

Across North America, leaking methane from wellbores has killed vegetation, contaminated groundwater and infiltrated buildings resulting in dangerous and fatal explosions in both urban and rural environments.

http://www.thetyee.ca/News/2014/06/0...-Energy-Wells/