Refracking wells?

In an Q and A interview in the Williamsport Gaurdian, Richard Adams , a spokesman for Chief Oil and Gas said—
“Re-fracking is not a common event in the Barnett or any other shale field at this time and I would not expect it to be common in the Marcellus at any point in the future.”

If this were true, it would be a good thing.

If a well is only fracked once, then the number of fracks would equal the number of wells but if wells are refracked every few years the number of fracks grows exponentially larger than the well count.
Each refrack uses more water than the last, 25% more is the given figure.  Each refrack generates a new load of highly contaminated waste water. Each refrack restresses the well casings with 6000 to 8000 pounds per square inch of pressure.  Each refrack invites the danger of surface contamination by spilled or leaked concentrated chemicals.

When some folks in the Barnett Shale area of Texas were asked if Adam’s statement was true they gave these replies.

“Baloney!  I don’t have time to find references now but they are available. They don’t have to get a permit so no one really keeps track but it’s common knowledge.”

“Chk (Chesapeake) has told folks they plan to refrack many times over the life of the reserves..like every 3 or 4 years.”

“If they are on the lease side trying to say you will make lots of money…,and they refrack When they are talking about the environmental side, they say the opposite.”

“FALSE.  One of the pad sites near my home is refracked regularly due to several wells on the site. The frack trucks are also a common site on the highway. Ubiquitous is the word.”

“Absolutely they will refrack  and have already at many wells. The Industry folks I talked to relayed the probability of  every 3 to 5 years  depending on the well.”
And here’s what the industry has to say about it.

“It has been established that only 10% of GIP [gas in place] is recovered with the initial completion. Refracturing the shale can increase the recovery rate by an additional 8% to 10%. Simple reperforation of the original interval and pumping a job volume at least 25% larger than the previous frack has produced positive results in vertical shale wells.”

source:  Halliburton. Jan. 2007. “Developing Gas Shale Reserves .“ Advances in Unconventional Gas. A Hart Energy Publication. p. 28.
Focus on the Marcellus Shale By Lisa Sumi
FOR THE OIL & GAS ACCOUNTABILITY PROJECT/
EARTHWORKS, MAY 2008
According to Halliburton, an oil and gas service company:
It is important to note that a well drilled in the Marcellus shale may have to be fracked several times over the course of its life to keep the gas flowing, and that each fracking operation may require more water than the previous one.

From a Devon investor report: (Devon is one of the major gas exploration companies in the Barnett shale)

In addition to the refracs, we have also drilled and completed several wells on 250-foot spacing rather than the 500-foot spacing that our existing proved reserves are based on. If the early success of the first several wells drilled on 250-foot spacing continues, there may be substantial additional reserves to be recognized in the Barnett Shale over the coming years.

Our gas drilling in the Barnett Shale and Selma Chalk continues to provide additional production and reserves as we continue to test the limits of each field, whether it is from down spacing, extending the limits of each field or refracking of existing wells. (emphasis added)

As an example of a successful refrac, Devon Energy has reported on a well from which production had declined from 2,000 mcfe/day to 500 mcfe/day after 4.5 years. A re-frac restored production to 1,600 mcfe/day initially, declining to 1,000 mcfe/day after 3 months, and has probably doubled the remaining reserves from this well.
I suppose this information speaks for itself.
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