REVOLVING CREDIT AGREEMENT DATED AS OF DECEMBER 18, 2006 AMONG ATLAS ENERGY OPERATING COMPANY, LLC, AS BORROWER; AER PIPELINE CONSTRUCTION, INC., AIC, LLC, ATLAS AMERICA, LLC, ATLAS ENERGY OHIO, LLC, ATLAS ENERGY RESOURCES, LLC, ATLAS NOBLE, LLC,...

Exhibit 10(w)

REVOLVING CREDIT AGREEMENT DATED AS OF DECEMBER 18, 2006

AMONG ATLAS ENERGY OPERATING COMPANY, LLC, AS

BORROWER; AER PIPELINE CONSTRUCTION, INC., AIC, LLC,

ATLAS AMERICA, LLC, ATLAS ENERGY OHIO, LLC, ATLAS ENERGY

RESOURCES, LLC, ATLAS NOBLE, LLC, ATLAS RESOURCES, LLC,

REI-NY, LLC, RESOURCE ENERGY, LLC, RESOURCE WELL

SERVICES, LLC, AND VIKING RESOURCES LLC AS GUARANTORS;

WACHOVIA BANK, NATIONAL ASSOCIATION AS ADMINISTRATIVE

AGENT AND ISSUING BANK; BANK OF AMERICA, N.A. AND

COMPASS BANK AS CO-SYNDICATION AGENTS; BANK OF

OKLAHOMA, N.A., U.S. BANK, NATIONAL ASSOCIATION AND BNP

PARIBAS AS CO-DOCUMENTATION AGENTS AND THE LENDERS

SIGNATORY HERETO $250,000,000 SENIOR SECURED REVOLVING

CREDIT FACILITY WACHOVIA CAPITAL MARKETS, LLC AS LEAD

ARRANGER