Categorical Exclusion Determinations: B4.6

Emergency Installation of Concrete Pad for Western's Communication Tower at Valley Farms Substation CX(s) Applied: B4.6 Date: 04/01/2014 Location(s): Arizona, Arizona Offices(s): Western Area Power Administration-Desert Southwest Region

Deering Lake and Yuma Substation Upgrades CX(s) Applied: B4.6 Date: 03/06/2014 Location(s): Colorado Offices(s): Western Area Power Administration-Rocky Mountain Region

Glen Canyon Substation 345 Kilovolt - Sulfur Hexafluoride and Concrete Pad Installation CX(s) Applied: B4.6 Date: 02/06/2014 Location(s): Arizona Offices(s): Western Area Power Administration-Desert Southwest Region

Big George-Heart Mountain 69 Kilovolt Transmission Line Glendale Tap Replacement, Park County, Wyoming CX(s) Applied: B4.6 Date: 01/21/2014 Location(s): Wyoming Offices(s): Western Area Power Administration-Rocky Mountain Region

Cable Trenching in the Gila Substation CX(s) Applied: B4.6 Date: 01/13/2014 Location(s): Arizona Offices(s): Western Area Power Administration-Desert Southwest Region

Edgeley Substation CX(s) Applied: B4.6 Date: 11/19/2013 Location(s): North Dakota Offices(s): Western Area Power Administration-Upper Great Plains Region

Insulator Replacement on North Bonneville-Midway No. 1 Transmission Line (update to previous CX issued 7/16/13) CX(s) Applied: B4.6 Date: 11/12/2013 Location(s): Washington Offices(s): Bonneville Power Administration

Real-Time In-Situ Carbon Dioxide Monitoring (RICO2M) Network for Sensitive Subsurface... CX(s) Applied: A11, B4.6 Date: 09/30/2013 Location(s): Texas Offices(s): National Energy Technology Laboratory

Echo Lake Substation Isolation Disconnect Switch Installation CX(s) Applied: B4.6 Date: 09/30/2013 Location(s): Washington Offices(s): Bonneville Power Administration

Yaak Substation Transformer Replacement CX(s) Applied: B4.6 Date: 09/18/2013 Location(s): Montana Offices(s): Bonneville Power Administration