Conservation well

What is a "conservation well" on a well pad? I was looking at the DEP mapping and inspection notes for the well pad that we have acreage in and noticed that one of the well heads is specifically noted as a conservation well. It is in PA.

Alicia

http://www.dcnr.state.pa.us/topogeo/econresource/oilandgas/marcellus/marcellus_faq/Regulatory/index.htm

Q. What is the difference between a “conservation” well and a “deep” well?

A “conservation” well is defined as any well penetrating the top of the Onondaga Limestone (or equivalent formation when the Onondaga is absent) and is at least 3,800 feet deep. This term is defined by the Oil and Gas Conservation Law. The Pennsylvania Geological Survey considers a “deep” well to be any well that penetrates the Middle Devonian Tully Limestone.

Clint Liles

Thanks Clint! I goggled it, but couldn't find anything!