The Sinphuhorm natural gas field is located on the Khorat plateau in northeast Thailand (approximately 290 miles northeast of Bangkok). It is contained primarily in the EU1 and E5N production licenses. The field has gas trapped in mid-Permian limestone and dolomite reservoirs of the Pha Nok Kao formation.

Coastal owns a net 13.7% working interest in EU1/E5N via its 39% holding of APICO, LLC. EU1/E5N is operated by Hess. The Sinphuhorm field produces greater than 90 Mmcfpd of gas and 500 bopd of condensate. The gas is sold under a 15-year gas sales agreement to the Nam Phong power plant. The GSA expires in 2021 and covers approximately 500 bcf of gas to be delivered. Pricing for the GSA is based on oil product pricing.

At March 31, 2012 2P reserves, net to Coastal, at Sinphuhorm were 21.4 Mmboe per the Company’s third party interim reserves evaluation performed by RPS Energy Ltd.