Putting Water Use in Context
Because Pennsylvania has one of the largest water resources in the nation, we recognize that being good stewards of these resources is extremely important. We recognize that some people have questions about how water resources are managed, and we're committed to demonstrating that it is a high priority.
Every aspect of water in Marcellus Shale development is regulated, reviewed and inspected by the DEP in Pennsylvania. It's important to note that the industry's current water consumption makes up far less than one percent of the Commonwealth's daily water consumption of 10 billion gallons. In fact, even if anticipated peak drilling levels tripled, the industry would still make up less than one percent of Pennsylvania's daily water consumption.
Where Our Water Comes From
The water used for Marcellus Shale development comes from a number of sources, all of which must be reviewed and approved by regulatory agencies. Most of the water we use comes from the water company. We can put a meter on a nearby water line and use water just as you would in your home. Another portion comes from approved surface waters, such as nearby rivers. Regulators determine how much and when we can withdraw water from a surface source. Finally, we are able to recycle and reuse a significant portion of our water.
Protecting Water Wells
Before a natural gas well is drilled, we survey the area and conduct water testing for all water wells within 2,500 feet of our location. We then provide the findings of those pre-drilling tests to landowners so they have a baseline of their water quality. Pennsylvania has specific standards and regulations about how we construct our wells. Each well typically has five layers of fully cemented steel casing strings to fully isolate our wellbore, or drill hole, from groundwater. That means there's about three million pounds of steel and concrete to protect drinking water wells.
Even though Pennsylvania has the second highest number of citizens who rely on drinking water wells, it's also one of only four states that have no standards, laws, regulations, or inspections governing the construction of drinking water wells. In fact, a study performed by the state found that approximately 43 percent of all drinking water well supplies do not meet recommended safe drinking water standards*. This is completely unrelated to natural gas drilling activity and due to the lack of standards and regulations. The same study found that the majority of those water well owners were unaware that their water did not meet safe drinking water standards.
*Source: "Drinking Water Quality in Rural Pennsylvania and the Effect of Management Practices," 2009
Extracting Natural Gas
In order to release the natural gas trapped within the Marcellus Shale, Range Resources uses a proven and tested technology called hydraulic fracturing. This technology has been in use for the last sixty years and has been used to complete more than a million oil and natural gas wells in the United States, including more than 100,000 wells in Pennsylvania. For the Marcellus Shale, we inject around four million gallons of water and sand into the thick layer of rock found more than a mile below the surface. The water creates small fractures about the width of a sheet of paper in the rock, and the sand holds those small fractures open to release the gas from rock formation and flow freely.
We also use a highly diluted blend of additives to keep the wellbore free of bacteria and scaling and to allow for a more efficient injection of the water. Four additives are used in highly diluted forms to complete this task. All of these additives are found in our daily lives and collectively make up about one-seventh of one-percent of the injection. The remaining 99.86 percent is water and sand.
Here is a complete list of this solution on a well-by-well basis.
Water Recycling and Reuse
After we inject the water and begin the process of producing natural gas from the Marcellus Shale, we collect the water in a closed-loop system at the surface. This water is then cleaned onsite to remove potential heavy metals and solids from the shale formation, or it is trucked to a treatment facility. Either way, the result is clean salt water. The salt composition is the same that you'd find in table or road salt and makes up about nine percent of the water. That salt water is then blended with fresh water at a regulated and approved water holding facility where it is then reused at a future natural gas well location. Some water may also be taken to a regulated deep disposal well, which is how roughly 85 percent of all liquid wastewater is disposed of in the United States.