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Marcellus Shale

Gas well drilling in the Marcellus Shale

NOTE: The draft scope for a supplemental generic environmental impact statement related to Marcellus Shale drilling is now available for review and comment. The schedule of public scoping meetings and staff's scoping presentation (PDF, 357 KB) are also now available.

What is the Marcellus Shale?

Map of New York State showing the extent of the Marcellus Shale formation
The boundaries of the Marcellus Shale
formation in NY. Click on the map for
a larger image.
The Marcellus Shale is a black shale formation extending deep underground from Ohio and West Virginia northeast into Pennsylvania and southern New York. Although the Marcellus Shale is exposed at the ground surface in some locations in the northern Finger Lakes area, it is as deep as 7,000 feet or more below the ground surface along the Pennsylvania border in the Delaware River valley. Drilling activity is expected to focus on areas where the Marcellus shale is deeper than 2,000 feet.

How much natural gas is in the Marcellus Shale?

Geologists estimate that the entire Marcellus Shale formation contains between 168 trillion to 516 trillion cubic feet of natural gas throughout its entire extent. It is not yet known how much gas will be commercially recoverable from the Marcellus in New York. To put this into context, New York State uses about 1.1 trillion cubic feet of natural gas a year.

Why all the interest in the Marcellus Shale now?

Although geologists have long known about the natural gas resources of the Marcellus Shale formation, the depth and tightness of the shale made gas exploration and extraction very difficult and expensive. Interest has increased significantly of late due to:

  • recent enhancements to gas well development technology, specifically horizontal drilling and hydraulic fracturing,
  • the proximity of high natural gas demand markets in New York, New Jersey and New England and
  • the construction of the Millennium Pipeline through the Southern Tier.

Questions have been raised about possible environmental and community impacts. Most concerns are related to water use and management and the composition of the fluids used for fracturing the shale. These are discussed below.

Landowners have been approached by energy and land management companies about leasing their land. Although leasing is not regulated by the Department, information about leasing gas well rights is available on our website.

What are horizontal drilling and hydraulic fracturing?

Horizontal drilling and hydraulic fracturing are legal and common in New York. The majority of wells in the Marcellus Shale will be hydraulically fractured.

A horizontal well in the Marcellus Shale
A horizontal gas well. Image courtesy Brad Cole,
Geology.com
Horizontal drilling has been used in New York since the 1980s. A "horizontal well" is first drilled down vertically to a depth above the target gas-bearing rock formation. Special tools are then used to curve the well so that the hole is drilled horizontally within the gas-bearing rock for up to several thousand feet. Ten percent of DEC's 2007 well drilling permits were for directional and horizontal wells.

Except for special tools used underground, horizontal drilling is performed using the same equipment and technology as vertical drilling, with the same protocols in place for aquifer protection, fluid containment and waste handling.

Benefits of horizontal drilling:

  • Maximum contact with the gas-bearing rock formation, so that more gas can be produced from a single well.
  • Multiple horizontal wells can be drilled laterally from the same surface location, so that less of the ground surface is disturbed compared to using vertical wells to produce the same amount of gas.

Hydraulic fracturing consists of pumping a fluid and a propping material such as sand down the well under high pressure to create fractures in the gas-bearing rock. The propping material (usually referred to as a "proppant") holds the fractures open, allowing more gas to flow into the well than would naturally. No blast or explosion is created by the hydraulic fracturing process, which has been used in New York since at least the 1950s. Hydraulic fracturing technology is especially helpful for "tight" rocks like shale.

Quantity of water needed for hydraulic fracturing
Hydraulic fracturing of the Marcellus Shale will require large volumes of water to fracture the rocks and produce the desired amount of gas. Each well may use more than one million gallons of water.

The hydraulic fracturing fluid typically contains compounds added to the water to make the hydraulic fracturing process more effective. These may include a friction reducer, a biocide to prevent the growth of bacteria that would damage the well piping or clog the fractures, a gel to carry the proppant into the fractures, and various other agents to make sure the proppant stays in the fractures and to prevent corrosion of the pipes in the well. The Department is assessing the chemical makeup of these additives and will ensure that all necessary safeguards and best practices are followed.

More information, including general information about fracturing fluid additives, is available in the report Hydraulic Fracturing Considerations for Natural Gas Wells in the Marcellus Shale released in September 2008 at the Ground Water Protection Council's Annual Forum.

Disposal of hydraulic fracturing fluid
Fluid removed from the well is required by law to be handled, transported and disposed of properly.

Did New York recently approve a new type of drilling?

No. Governor David A. Paterson recently approved a bill that extends uniform gas well spacing rules and establishes boundary setbacks to protect the interests of adjacent property owners. This new law has been widely misreported as allowing a new type of drilling, or somehow making it easier to get the environmental permits necessary for drilling. In fact, the new law only addresses well spacing. It authorizes nothing new nor in any way does it reduce the environmental review needed before a drilling permit is issued.

Protecting the Environment, Water Resources and Public Water Supplies

DEC's Regulatory Program and Permitting Process
New York State's well-established regulatory program oversees drilling. DEC's Mineral Resources staff - averaging 22 years of experience per person - conducts a rigorous permitting process which protects the environment and landowner before the permit is issued, during drilling, when the well is plugged and when the site is restored. This includes:

  • Review of each drilling application for environmental compliance before any drilling, which involves;
    • Screening of the proposed well location to identify any environmental sensitivities, and
    • Review of the proposed well design is to ensure that it is protective. (See Related Links at right.) This ground water protection diagram (PDF, 204 KB) illustrates how the required well casing and cement protects fresh water aquifers;
  • On-site inspection of actual drilling operations; and
  • Enforcement of strict restoration rules when drilling is completed.

Municipal water wells are protected by the requirement for a full environmental assessment if a proposed oil or gas well is within 2,000 feet of the municipal well and a supplemental environmental impact statement if within 1,000 feet. All groundwater, including private wells, is protected by strict construction requirements for oil and gas wells.

Other Department programs address potential impacts to wetlands, streams and sensitive habitats through our own permitting and approval requirements and through our participation on the Delaware and Susquehanna River Basin Commissions. These groups have their own regulatory programs (see below).

As a result of New York's rigorous regulatory process, the types of problems reported to have occurred in states without such strong environmental laws and rigorous regulations haven't happened here. No known instances of groundwater contamination have occurred from previous horizontal drilling or hydraulic fracturing projects in New York State.

The Environmental Impact Review Process

Photo of an active gas well in Chemung Co. after site reclamation
An active natural gas well in Chemung County after the drilling
and completion work is done and the site has been reclaimed
A Generic Environmental Impact Statement (GEIS) provides a comprehensive review of the potential environmental impacts of oil and gas drilling and production and how they are mitigated. The Department has initiated a formal public review process to supplement this GEIS to ensure that any issues unique to Marcellus and other horizontal shale formation drilling are adequately addressed. Governor Paterson directed DEC to supplement the GEIS when he signed the spacing bill (see Offsite Links at right).

While the process of scoping and preparing the Supplemental GEIS is ongoing, any entity that applies for a drilling permit for horizontal drilling in the Marcellus Shale and opts to proceed with its permit application will be required to undertake an individual, site-specific environmental review. That review must take into account the same issues being considered in the Supplemental GEIS process and must be consistent with the requirements of the State Environmental Quality Review Act and the state Environmental Conservation Law

Use our on-line data base to find information about existing wells and permit applications.

The Draft Scope

The draft scope for the Supplemental GEIS was released for public review and comment on October 6, 2008. The Department is accepting written comments through December 15, 2008.

Topics in the draft scope include the potential impacts of:

  1. Water withdrawals from surface waterbodies and groundwater sources for hydraulic fracturing
  2. Transportation of water to the well site
  3. The use of additives in the hydraulic fracturing fluid
  4. Space and facilities required at the well site to ensure proper handling of water and additives
  5. Removal of spent fracturing fluid from the well site and its ultimate disposition
  6. Noise, visual and air quality considerations
  7. Potential community impacts

Public Scoping Meeting Schedule

Six public scoping meetings on the dates and at the locations listed below, have been scheduled to provide an opportunity for all interested persons to comment. A stenographer will record the public comments. Each meeting location listed below will open at 4:30 pm, with the formal meeting beginning at 5:15 PM. Brief remarks by Department staff will be followed by public comments starting at 6:00 PM.

Thursday, November 6, 2008: Allegany-Limestone High School Auditorium/Theater, 3131 Five Mile Road, Allegany, NY 14706.

Wednesday, November 12, 2008: Haverling High School Auditorium, 25 Ellis Avenue, Bath, NY 14810.

Thursday, November 13, 2008: Southside High School Auditorium, 777 South Main Street, Elmira, NY 14904.

Monday, November 17, 2008: Broome County Community College, West Gym, 901 Upper Front Street, Binghamton, NY 13902.

Tuesday, December 2, 2008: SUNY/Oneonta, Hunt Union Ballroom, 108 Ravine Parkway, Oneonta, NY 13820.

Thursday, December 4, 2008: Sullivan County Community College, Fieldhouse, 112 College Road, Loch Sheldrake, NY 12759.

Other Agencies with Jurisdiction

The Susquehanna River Basin Commission (SRBC) and the Delaware River Basin Commission (DRBC) regulate the rate and volume of water withdrawals within their respective basins. These regional water authorities must review and approve water used for hydraulic fracturing projects in the Marcellus Shale. DEC has representatives on both Commissions and also regularly communicates with the New York City Department of Environmental Protection regarding the city's upstate water reservoirs.

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