725-6MW-2093 - Monitoring Well Abandonment Project

Caltrans has approved an encroachment permit for Phillips 66 to permanently abandon three monitoring wells—MW-7, MW-8, and MW-12—at the I-405 offramp at Carson Street, postmile 10.57 in Carson, Los Angeles County. Wells MW-7 and MW-8 are located outside the Caltrans right-of-way, while MW-12 is within it, necessitating traffic control measures such as the placement of signage, closure of the right-hand shoulder, and closure of the left-turn lane within the state-maintained area. Work will include utility locating using ground-penetrating radar to ensure safety, removal of MW-12 in strict accordance with a plan reviewed and approved by the Regional Water Quality Control Board, and resurfacing to meet Caltrans technical standards. All excavation will be limited to a maximum depth of 12 inches, with an average width of 24 inches and a maximum length of 24 feet, avoiding any disturbance to existing public utilities. No new right-of-way acquisition or utility relocation is required, and all activities will be conducted without expanding the existing work area beyond the specified dimensions and locations.