FHWA-CA-EIS-83-14-DS2 State Clearinghouse No. 83051706

4-SM-1 KP54.7/66.0 (PM34.0/41.0)

4210-112371

Devil's Slide Improvement Project

Route 1 from Half Moon Bay Airport to Linda Mar Boulevard in Pacifica,

San Mateo County, California

SECOND SUPPLEMENTAL ENVIRONMENTAL IMPACT STATEMENT/

SECOND SUPPLEMENTAL ENVIRONMENTAL IMPACT REPORT

Submitted Pursuant to (State) Division 13, Public Resources Code and (Federal) 42 U.S.C. 4332(2)(C) by the

U.S. DEPARTMENT OF TRANSPORTATION

Federal Highway Administration

and

THE STATE OF CALIFORNIA

Department of Transportation

___________________

ABSTRACT

The original 1986 FEIS presented three alternative alignments with various design options to provide a safe, dependable and stable highway between the Half Moon Bay Airport and Linda Mar Boulevard in the City of Pacifica. From these alternatives, the Federal Highway Administration (FHWA) and Caltrans selected the Martini Creek alignment, a two-lane facility with an uphill climbing lane in each direction where grades are 6% or greater, as well as traffic safety design features. As a result of a NEPA lawsuit, the impact of estimated future project-generated noise was restudied in the 1995 Noise-Only Supplemental EIS/EIR. Again, the FHWA and Caltrans selected the Martini Creek alignment, but agreed to revisit the tunnel alternative in the reevaluation of the 1986 FEIS that was to follow (a tunnel alternative was previously evaluated in the 1986 FEIS as an alternative considered but withdrawn). Based upon the results of an independent tunnel feasibility report issued in October 1996, and updated cost estimates for the revised Martini Creek alignment alternative, FHWA and Caltrans determined that a tunnel alternative is a reasonable alternative for the proposed project and should be fully evaluated in the environmental process. Therefore, this second draft Supplemental EIS/EIR serves as both the revaluation of the original Final EIS for the Martini Creek alignment alternative and the initial NEPA evaluation of the tunnel alternative. The slide dewatering alternative is also evaluated in this document, but is considered not reasonable. Potential adverse impacts from the tunnel alternative could occur to the visual landscape and to wildlife. Mitigation measures to minimize these impacts include an extensive revegetation program and avoidance of sensitive habitat.

NO COMMENTS WILL BE ACCEPTED VIA EMAIL

The following individuals may be contacted for additional information concerning this document:

Comments on this draft document are due by May 12, 1999 and should be sent to Robert Gross at the above address.