United States Exploration Steven D. Durrett, CEO

Overview of U.S. Exploration  U.S. Exploration was a publicly-traded E&P company owning long-lived natural gas reserves with significant development drilling upside, with over 400,000 undeveloped acres.  U.S. Exploration was defensively managed by its previous managers with fewer than 200 company operated wells and minor non-operated interests in another 200 wells  U.S. Exploration’s focus was on exploitation of the Wattenberg Field with expansion opportunities located on other acreage in the Denver – Julesburg Basin  Initial acquisition was $57 million (including fees), financed with $32 million of equity from Greenhill Capital Partners and Lime Rock Partners along with $25 million of Senior Debt from Wells Fargo. In July 2004, the equity partners funded an additional $6 million to support the growth strategy  Purchase price was 4.4x EBITDA, $0.69 / Mcfe and 64% of PV-10 Energy

U.S. Exploration: Development Plan  Development Plan  Began in-fill drilling and re-completion programs designed to complete over 100 new wells per year  Drilled or re-completed approximately 300 new wells with 98% success  Since taking control of U.S. Exploration in January 2004, management team (10 employees) grew net production at a 47% CAGR and run-rate EBITDA at a 154% CAGR  The Company proved-up over 2,000 additional Proved and Probable well locations and developed an additional 4,000 unbooked Probable and Possible well locations  In March 2006, we closed the sale of U.S. Exploration to Noble Energy for total consideration of $411 million yielding an equity ROI of 7x and an IRR of 155% Energy

U.S. Exploration: Monthly Production Energy (Mmcfe / Month) 47% CAGR

U.S. Exploration: EBITDA by Quarter Energy ($ millions) 154% CAGR

U.S. Exploration: Per Unit Costs Energy $1.09 $0.99 $0.80 Pre-AcquisitionPost-Acquisition (1) Notes: (1) Other expenses consist of non-recurring transition expenses in 2004 and bonuses paid in 2005.

($ in millions) U.S. Exploration: Value Creation Energy -$60

Why Private Equity? Relief from expensive public regulatory burdens Drop below the radar to allow for restructuring and reinvention without micro-scrutiny Build your business and establish a track record in relative anonymity Management compensation structure