Tunneling to Resume Soon, Experts Say : Metro Rail: The subway openings under Hollywood Boulevard have been stabilized, MTA says. Officials see no further problems with sinking.

Engineers concluded Thursday that twin subway tunnels beneath Hollywood Boulevard are “in no danger of collapse”--despite the ground having sunk nine inches in one spot--and that tunneling beneath the famed thoroughfare can resume by the middle of the month.

After a two-week review, a panel of tunnel and soil experts reported that the subsidence resulted from loosely packed, sandy earth and soil drenched by ruptured water and fire lines in the area. The panel also blamed soils compacted by construction work and the failure of wooden wedges in the tunnels to hold under pressure.

However, the board told the Metropolitan Transportation Authority that the tunnels have been stabilized. With a few remedial measures, the panel said, boring can continue without danger of a repeat of last month’s settling, which forced the closure of several blocks of the boulevard near Hudson Avenue, the evacuation of dozens of residents and the rescue of sidewalk stars along Hollywood’s Walk of Fame.

The review board recommended that engineers re-grout a 200-foot stretch of one tunnel between Wilcox and Whitley avenues, where steel reinforcing columns were erected to shore up the tunnel liner. Workers were advised to pack surrounding soil to keep the earth more firmly in place.

“We will implement the board’s recommendations over the next several days in order to resume our tunneling operations by mid-September,” Edward McSpedon, the MTA’s chief executive officer for construction, said in a statement.

As workers tunnel westward, careful mining should cause the ground to sink one to two inches, which the review board characterized as an acceptable level of subsidence based on past experience.

Tunneling was suspended Aug. 20 after complaints by residents and merchants that the construction was causing more damage than the Northridge earthquake. Tenants on the boulevard reported cracks in floors and walls, criticizing a costly transit project that has been plagued by accusations of poor safety and construction.

Authorities sealed off nine blocks of Hollywood Boulevard from traffic a day later and ordered evacuation of 45 residents from a historic apartment building. More than two dozen businesses have filed claims with the MTA for lost revenue as a result of the closure.

Although two lanes of the four-lane boulevard are now open, some merchants complain that barricades continue to drive away potential customers.

“There’s no business on the street because of this. We have a barricade not 3 1/2 feet from our window and our front entrance,” said Ron Martek, co-owner of By George!, a menswear store. “People are walking by but hardly notice we’re here.”

MTA officials said they will continue to monitor buildings and street surfaces in the area.