Revised Noise Impact Assessment of Perryville Gas Storage LLC under CP13-23

Perryville Gas Storage LLC Docket No. CP13-23-000 Revised Noise Impact Assessment Page 2 Respectfully submitted, /s/ J. Gordon Pennington Attorney for Perryville Gas Storage LLC CC: All parties Juan Polit-FERC Staff March 11, 2013 Project 10006 Rev. 7 Altec Environmental Consulting, LLC Cavern Well No. 2 @ Franklin Parish, LA Noise Impact Assessment ALTEC Environmental Consulting, LLC Project 10006, Rev. 7 March 11, 2013 TABLE OF CONTENTS 1. Executive Summary ...................................................................................................................3 2. Introduction............................................................................................................................... 4 2.1 Background ................................................................................................................. 4 2.2 Scope ........................................................................................................................... 4 2.3 Site Description ........................................................................................................... 4 2.4 Federal Energy Regulatory Commission (FERC) ....................................................... 6 3. Noise Propagation Modeling.....................................................................................................7 3.1 Noise Sources...............................................................................................................7 3.2 Noise Modeling Parameters...................................................................................... 10 3.3 2000hp Unmitigated Model Results......................................................................... 10 3.4 2000hp Rig Mitigation ............................................................................................... 12 4. Recommendations and Conclusions ....................................................................................... 15 5. Disclaimer ................................................................................................................................. 16 APPENDIX A: SOUND LEVEL TERMINOLOGY .............................................................................. 17 Page 1 ALTEC Environmental Consulting, LLC Project 10006, Rev. 7 March 11, 2013 TABLES AND FIGURES Table 1: Cavern Well 2 GPS ............................................................................................................. 4 Table 2: Location of NSAs ...............................................................................................................5 Table 3: Sound Power Level (Lw) of 2000 Hp Cavern Well Drilling Rig Equipment .................... 8 Table 4: Modeling Input Parameters ........................................................................................... 10 Table 5: 2000hp Unmitigated Model - Downwind Conditions ( 5 m/s) .................................. 10 Figure 1: Aerial Photo of the Cavern Well 2 Area..............................