"By OGJ editors
HOUSTON, Nov. 12 -- Southwestern Energy Co., Houston, has proved 75% of its lease position in the Fayetteville shale in the Arkansas Arkoma basin, where its gross operated production exceeded 1.5 bcfd of gas in the quarter ended Sept. 30.

The company expects to have captured all of its acreage by mid-2012.

Southwestern has averaged 13 rigs in the play, down from 15 in the first 9 months of 2010, and expects to run 13 or fewer rigs there in 2011. It takes 8-9 rigs to keep production from declining. ...

Spacing issues
Based on the wells drilled to date, the company expects that 10-12 wells/sq mile are needed to effectively drain the reservoir. That works out to 65-acre spacing, at which the company has more than 520 wells on production.

“Early production performance from recent well spacing tests indicates there are areas of the field that may be economically developed at tighter spacing,” the company said.

“At this time we have confirmed that 20% of the roughly 600,000 net acres drilled to date can be drilled at 30 to 40-acre spacing; approximately 40% can be developed at 65-acre spacing; and the remaining 40% requires additional results to determine if development on tighter spacing than 65 acres is warranted,” the company said.

Horizontal well length averaged 4,503 ft in the quarter. "

http://www.pennenergy.com/index/petroleum/display/8646446476/articl...

The article is about how one company is developing its shale acreage - holding leases, spacing, how many drilling rigs are required to maintain the production level, etc.  One of the alleged benefits of forced pooling in PA is that it would minimize the surface impact.  But, imo, unless minimum spacing is included in any legislation, the gascos are going to space as tightly as is (more) profitable.  
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