St. John’s Hospital and Health Center in Santa Monica will be demolished piecemeal over the next 30 years and replaced with a new $270 million complex.

The environmental impact report on the 1.4 million-square-foot project is out for public comment until Oct. 20, said Suzanne Frick, Santa Monica’s planning director.

The first phase of the two-phase project will replace all of the clinical facilities on the hospital’s 535,000-square-foot campus, which is bounded by Santa Monica Boulevard, Arizona Avenue, 23rd Street and 20th Street.

Construction on the first portion of the first phase, the underground physical plant facility, could begin by next spring if the Santa Monica City Council approves the project in January, said Terry Muldoon, vice president at St. John’s.

The hospital then plans to demolish its behavioral medicine facility in the fall of 1998. The entire first phase of construction is expected to last six years, and will include replacement of the hospital’s inpatient facilities, a new diagnostic and treatment facility and a new entry plaza and underground parking structure. The hospital intends to remain fully operational throughout the six years of construction, Muldoon said.

“It’s going to be an aggressive and arduous undertaking, but we think we’ve got it in hand,” he said.

The first phase of the construction will actually reduce the hospital’s size by 65,000 square feet to 470,000 square feet, in part because the number of hospital beds will be reduced by more than half to 150.

St. John’s, which was badly damaged in the 1994 Northridge earthquake, devised its development plan when it repaired the quake damage. At the time of the earthquake, all hospitals in California were given the choice of either repairing their facilities to current seismic code or fixing their facilities to the building’s original seismic code and then negotiating a timeline for phased-in replacements to begin by Oct. 1999.

St. John’s chose the latter. Its present development schedule is more than a year ahead of that deadline.

The replacement project is being funded by $140 million in Federal Emergency Management Agency funds and $130 million from a fund-raising campaign, Muldoon said.

The new hospital will have ball bearings under its structural columns, so the building can move independently during a quake. It will also have its own infrastructure such as water, fuel and septic storage so that it can remain operational during a quake.

The replacement of the hospital’s clinical facilities is the first priority, then the project will move into phase two replacement of the research and auxiliary services. Those first two phases will bring the hospital into “the future of health care,” by adding such elements as acupuncture services and assisted-care living facilities.

The 916,000-square-foot phase two is not yet funded, Muldoon said, but the hospital’s proposed development agreement with the city would allow for construction of phase-two elements to begin concurrently with phase one.

During the public comment period, “the city asks that we disclose all that we might do,” Muldoon said. For example, St. John’s would like to replace its 52,000-square-foot John Wayne Cancer facility with a new cancer center almost three times that size.

No additional land will be acquired by the hospital to accommodate its huge project. The hospital gave itself a 30-year timeline for both phases of the project to allow leases in medical office buildings it owns on the property to expire, Muldoon said.