A single-bore tunnel could be built through Montara Mountain, according to the Federal Highway Administration, but for safety reasons it would have to be at least 58-feet wide, which would cost millions more to construct than the 46-foot-wide alternative preferred by environmentalists.
In a letter dated Monday from FHWA administrator Fred Hempel to the San Mateo County Board of Supervisors, the FHWA laid down several conditions for the independent tunnel study. Tunnel supporters responded that the conditions would slant the study against a tunnel.
The letter also suggested that the petition now being circulated to gather signatures for a countywide vote on the tunnel could force the FHWA and California Department of Transportation to not build any permanent repair for Highway 1 through Devil's Slide.
"The major point to me is their predetermination of the tunnels to be studied," complained Montaran Chris Thollaug of Save Our Coast, which is co-sponsoring the petition drive.
"By predicating the (specifications) of the tunnel, that's a setup to ensure the cost is unfavorable," he added.
Although the letter was scheduled for discussion by supervisors at its Tuesday morning meeting, it did not receive the letter until late Monday afternoon and delayed the matter until Jan. 9.
The letter was in response to complaints by supervisors that the intended independent tunnel study by a top-notch tunnel consultant was including CalTrans too much and predetermining things that should be left to the consultant.
According to the letter, supervisors will be allowed one vote in determining who the consultant is that does the study, along with one vote each for FHWA and CalTrans.
The letter states that "it is in everyone's interest . . . that the tunnel consultant be authorized to undertake whatever investigations are necessary to ensure reports that will allow supportable decisions to be made in the future," but then sets limitations on what the FHWA will accept in the interest of "features necessary for a safe roadway."
"Although CalTrans has expressed strong support, with good cause, for a four-lane, double-bore tunnel, FHWA . . . has established minimum single-bore cross sections at 58 feet and 66 feet . . . FHWA does not believe a 46-foot or 48-foot cross section would provide a safe and reasonable facility and be an appropriate expenditure of public funds."
But tunnel supporters point to standards established by the American Association of State Highway Officials that say a two-lane, two-way tunnel should have two 12-foot-wide lanes and two eight-foot-wide shoulders, totalling 40 feet. With 2.5-foot-wide pedestrian walkways on both sides added, it totals 45 feet, Thollaug said.
The FHWA has also concluded that a "Design/Build contract," which could save construction time, is not legal under California law and will not be considered.
In addition to deflating tunnel supporters, the letter took a shot at the proposed tunnel initiative, calling it "premature given the status of our study. If such a provision were enacted, it could ultimately force a no-build decision unless supported by the study conclusions and subsequent decisions of CalTrans and FHWA.
Activist Lennie Roberts said the assertion proves "the public has to tell them what to do."