Energy In Depth Ohio recently visited a Class II injection well to get a first-hand look at the disposal well process.  Our host, Dave Hill, President of David R. Hill, Inc, gave us an all access tour of his facilities and showed us the numerous  safety and environmental safeguards in place at these facilities.  We share that experience with you on this blog to help Ohioans gain a better sense of how this asset safely disposes  byproducts from oil and natural gas development.

Injection Well Background

Injection wells have been regulated by the U.S. EPA for nearly 40 years under the Safe Drinking Water Act.  In that time there have been over 144,000 Class II injection wells permitted and constructed  in the United States.  Here in Ohio, our Class II Injection well program is regulated under the Ohio Department of Natural Resources after they received primacy from the US EPA in 1985.  Ohio has permitted 181 injection wells  for disposal of produced water from oil and natural gas development.

Steps Involved in the Injection Well Process

There are primarily four steps that go into the injection well process at Mr. Hill’s facility.

Once the water leaves the water trucks, it is pumped into the storage tanks.  It is allowed to settle out by gravity, then the water is pumped into the pumped house.  We have two large Triplex pumps that take the water and pump the water back into the ground in a well just a few feet behind us at 8,900 feet deep.  After the trucks unload the brine, it is pumped into large storage tanks on site where it settles out by using gravity. – Dave Hill

Although the process seems simple enough, it is actually a very delicate process that all begins when a brine truck comes to the site and parks in the bay.  Once in the bay, the driver hooks a hose to the brine tank on the truck and pumps the produced water into the well’s storage tanks.

When the trucks are finished pumping they fill out a report detailing what was hauled and the natural gas well site where the liquids originated among other items.  The report is in essence a timeline from pick up to delivery – much like the system in place to track a Fed Ex or UPS package.

It contains the UIC number, who the truck owner is.  The day they picked it up. The time they picked it up. Who the drive is and where they took it.  They brought it to our well, our permit number. API permit number.  It has to have the API permit number where it came from, whether its pit water or production water and then the time they dispose it.  So it is literally like a chain of custody. – Dave Hill

There are 21 tanks on Mr. Hill’s operation including four large storage tanks where produced water is pumped.  The water is then cycled through the remaining 14 tanks until it is transferred into the pump house.  The gravity allows most of the dirt or rocks to settle before being transferred to the pump house.

With these storage tanks holding produced water, an operator takes great measure to ensure proper protections are in place. The storage tanks actually sit within a berm with thick plastic lining the area.  The berm is designed to hold the entire amount of liquid held in the storage tanks if all of it were to escape- a very unlikely proposition.

If, in the very rare circumstance there is a leak, there is a sump pump designed to pump the leaked liquid back into the storage tanks for proper disposal.

Once in the pump house, the produced water is filtered to remove any dirt and rocks remaining in the water as those remnants could plug the well.  Once the produced water is filtered it then goes to one of the Triplex pumps for disposal.

The disposal well itself contains multiple layers of steel and concrete designed to protect the water aquifer from potential contamination.  Dave Hill explains the well’s safeguards in the video below including the levels of redundancy designed to exceed those in place in the airline industry for example.

8,902 feet deep is the total depth.  We have three layers of casing, surrounded by three layers of cement. So if there was to be an issue here, the water would literally have to break through 4 layers of steel and 3 layers of cement to contaminate the fresh water. – Dave Hill

The well itself is outside the pump house and is smack dab in the middle of a functioning cow pasture.  When walking to the well you couldn’t help but notice that the cattle graze all around the fenced in well.  Luckily I missed stepping in more than a few cow patties.

The disposal site is roughly the size of a parking spot fenced in to make sure the cows do not disturb the operation.  As you can see in the video below the cows graze right beside the fenced in area and are not bothered by the operation.

The elaborate set of pipes takes the produced water from the pump and injects it into the cased and cemented well.  At the site is also a telemetry device that enables remote monitoring of the well which allows the well to be monitored inside of the pump house as well as from other remote locations.

A disposal well tour is not something most folks have an opportunity to do.  However, it is a worthwhile activity as it provides perspective one could never get otherwise.  That is the understanding that disposal wells are a sophisticated and environmentally friendly way of disposing produced water and are a testament to the high safety measures operators take in developing our natural resources.

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