Sep. 7--HARRISBURG -- The scope of natural gas drilling activities in Northeast Pennsylvania and New York state's Southern Tier should become more apparent when the Susquehanna River Basin Commission meets this week.

The interstate agency is set to take action on nearly 50 applications by natural gas companies to use basin water for drilling projects in the Marcellus Shale formation, the site of a drilling boom for gas deposits pocketed in layers of shale.

Water is essential to these drilling operations. Operators inject large amounts of water several thousand feet underground to break up the shale and reach the gas deposits.

Some big names in this energy industry -- Chesapeake Appalachia LLC, Cabot Oil & Gas Corp. -- are among the companies seeking approval to either withdraw water from streams and other surface water supplies or consume water through evaporation or other methods in their operations.

Among the applications up for consideration are Chief Oil & Gas LLC's plan to withdraw water from Sugar Creek in Bradford County, Cabot's plan to withdraw water from Bowmans Creek in Wyoming County and Chesapeake Appalachia's plan to consume water for operations in Bradford, Susquehanna and Wyoming counties.

The commission will consider the applications at a public hearing starting Thursday at 1:30 p.m. at Bucknell University in Lewisburg. The commission will take action on a new rule aimed at streamlining review of natural gas drilling applications.

The commission, which includes representatives of Pennsylvania, New York, Maryland and the federal government, has unique powers to regulate water use in the Susquehanna Basin. These include authority to approve or reject surface water withdrawals and consumptive water use above certain thresholds.

Pennsylvania state officials lack this authority. Therefore, when natural gas drillers operate outside the 27,000-square-mile Susquehanna Basin, they don't have to seek specific approval for the right to withdraw water. Abiding by environmental protection laws is a different matter.

The commission has stepped up its oversight of natural gas drilling in recent months. The commission announced last month that it will require natural gas drillers to obtain prior approval, regardless of the amount of water being used. This review will focus on the quantity and rate of water usage, location of the withdrawal, and the impact on the physical, biological, chemical and hydrological characteristics of water resources.