Hundreds Of Vertical Oil Wells Damaged By Horizontal Fracking by Tsvetana Paraskova, Sep 21, 2017, Oilprice
At least 450 conventional vertical wells in Oklahoma’s Kingfisher County have been damaged by horizontal fracturing, the Oklahoma Energy Producers Alliance (OEPA) said in a study, The Oklahoman reports.
OEPA, a group of Oklahoma oil and gas companies concerned with protecting their rights as conventional vertical producers and royalty owners, says that “hundreds if not thousands of wells are being destroyed by horizontal frac jobs.” All these wells paid 7 percent gross production tax (GPT) and are being replaced by wells paying 2 percent GPT, the alliance says, asking lawmakers to eliminate the “special 2 percent tax rate on new wells to the historical level of 7 percent that all other producers of existing wells pay.”
“I believe nearly every vertical well in Kingfisher County will be negatively impacted by horizontal frack jobs at some point,” OEPA founder Mike Cantrell told The Oklahoman. “We’re just trying to get people to get fair value for their property up front before the damage is done,” he added.
Matt Skinner, spokesman of the Oklahoma Corporation Commission, told The Oklahoman that the commission had investigated and verified 20 cases of damaged vertical wells due to horizontal drilling nearby, with most of the damaged wells showing environmental damage. Another 55 wells await inspection or are already under review.
“We have a well-established vertical world, and we have a new horizontal world. The issue is how can these two worlds live together,” Skinner said.
“Wells are obviously being damaged. We know this is happening. It is a problem that needs to be addressed, and to address it we need more data,” the spokesman told The Oklahoman.
A few weeks ago, a federal jury in Oklahoma City awarded US$220,000 in to two Oklahoma oil firms—H&S Equipment Inc and Mark Holloway Inc— damages incurred by a “well-bashing” incident two years ago by Felix Energy, which was later acquired by Devon Energy Corp. [Emphasis added]
Oil and Gas Producers Find Frac Hits in Shale Wells a Major Challenge by Trent Jacobs, JPT Digital Editor, 01 April 2017, Society of Petroleum Engineers
In North America’s most active shale fields, the drilling and hydraulic fracturing of new wells is directly placing older adjacent wells at risk of suffering a premature decline in oil and gas production.
The underlying issue has been coined as a “frac hit.” And though they have long been a known side effect of hydraulic fracturing, frac hits have never mattered or occurred as much as they have recently, according to several shale experts who say the main culprit is infill drilling.
“It is a very common occurrence—almost to the point where it is a routinely expected part of the operations,” said Bob Barree, an industry consultant and president of Colorado-based petroleum engineering firm Barree & Associates.
He added that frac hits are also an expensive problem that involve costly downtime to prepare for, remediation efforts after the fact, and lost productivity in the older wells on a pad site.
A frac hit is typically described as an interwell communication event where an offset well, often termed a parent well in this setting, is affected by the pumping of a hydraulic fracturing treatment in a new well, called the child well.
As the name suggests, frac hits can be a violent affair as they are known to be strong enough to damage production tubing, casing, and even wellheads.
Claudio Virues, a senior reservoir engineer with CNOOC Nexen, said frac hits have become a top concern in the shale business because they can affect several wells on a pad, along with those on nearby pads too. Based on his experiences in Canada and in south Texas, the question is no longer if a frac hit will happen, but how bad will it be.
“You usually have two scenarios,” he said. “One may be that you have a temporary loss of production, but you will recover to the trend that you had before. The other will be really bad for your production and reserves.”
He is alluding to the fact that some wells impacted by frac hits never fully recover and, in the worst cases, permanently stop producing after taking frac hits. The frequency of these outcomes are unknown as there are no publicly available statistics. In a small minority of cases, and in select formation types, frac hits have been known to increase production in the impacted well, but this is unusual. [Emphasis added]
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