L.A. officials: No active quake fault under Hollywood development site

Consultants dug trenches and took soil samples to determine whether an active earthquake fault runs underneath proposed development sites in Hollywood.
(Mel Melcon / Los Angeles Times)

The Los Angeles Department of Building and Safety has signed off on geology reports that found that no active earthquake fault runs under the site of a proposed 16-story development just east of the Millennium Hollywood project.

“We agree with their finding that there is no active fault on that specific parcel,” department spokesman Luke Zamperini said Thursday of the parcel at 6230 Yucca St., the former site of the KFWB radio studio.

The determination came after the city geologist asked the developer’s geologist to do additional seismic trenching earlier this year. A possible fault was found buried deep underground, but tests showed that it last moved so long ago that it was considered inactive. California law defines faults that ruptured within the last 11,000 years as active.


“Therefore, no building restrictions relative to potential fault-rupture are recommended for the subject site,” the building and safety department’s approval letter said.

The letter specified that during construction the project’s engineering geologist must observe all the excavations to verify there are no active faults under the property. A supplemental report of these observations must be submitted to the city, and “if evidence of active faulting is observed, the Grading Division shall be notified immediately,” the letter said.

The department’s approval comes just before the state geologist is expected to finalize a regulatory map of the Hollywood earthquake fault, which is scheduled to be released by mid-November. The preliminary map has been the subject of much debate because it placed the Hollywood fault zone through the KFWB site, as well as the iconic Capitol Records tower and Millennium project, where a developer plans to build Hollywood’s tallest skyscrapers, at 39- and 35-stories tall.

The final say over whether a structure can be built lies with city building officials, who must determine whether a developer has done sufficient underground study and proved a structure can be built safely away from any active faults.

The developer’s consultant, Michael Reader, has completed detailed seismic studies under the KFWB studios and the Millennium site, as well as two other properties at the intersection of Argyle Avenue and Yucca Street.

This summer Reader said his studies found no evidence of an active earthquake fault underneath the properties and asked the state to reflect that in its final zoning maps. He questioned whether the California Geological Survey had enough evidence to support designating an active fault zone through these properties.


Reader had said his firm, Group Delta, dug four trenches and took dozens of soil and sonar samples, which so far have cost the developers more than $1 million.

He said working on all four properties was like piecing together a “geological jigsaw puzzle,” and his firm was able to reach these conclusions only because they were hired and had access to study all the locations at the same time.

His firm did find minor faults under the two properties across the street from the Millennium and KFWB sites, but tests also showed these faults to be so old that they were considered inactive.

All of Reader’s data have been submitted to the state for consideration.

Reader declined to comment Thursday on the city’s approval of the 6230 Yucca St. fault report.

Zamperini said that with the approval letter the developer can now begin to submit other documents, such as an engineering report. There are a few more steps to go before the developer can apply for a building permit, he said. “This is just the beginning.”

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