SAC Minutes - 127 Edgehill Way 06-16-15.pdf

Minutes for SAC review for 127 Edgehill Way, San Francisco on June 16, 2015

Members of the SAC committee and the home owner’s team were present to begin the meeting at 1:00 p.m.  Harvey Hacker, Architect with the SAC committee, was not present in the meeting. A summary of the meeting follows:

* Lauren Zeller, Architect, gave a general description of the project. She said it is a new type VB building, it is a single family residence, approximately 4253 sq. ft., 4 stories.
* Patrick Drumm, Geologist, said the project is on the North side of Edgehill Way. All of Edgehill Mountain is predominantly Chert. Within the site, Chert is dipping 60 degree to the East. Most of the slope is stable. A landslide exposed in his test pit at the lower part of the site. The landslide extends beyond the subject property. Patrick thinks it is a shallow landslide. In his report, Patrick indicates east facing construction is prone to adverse bedding failure.
* Allen Gruen, Geotechnical Engineer, stated that the site has soil veneer over Chert bedrock. 
* Frank Rollo asked Allen Gruen to send the SAC members his June 15th letter. 
* Frank Rollo asked Allen Gruen to address creep force in the slope debris area in his Geotechnical report. Also, to submit documentations to support his recommended design criteria, including the seismic increment of 5H.
* Lou Gilpin, Geologist, recommended more test pits. The pits should go at least 3’-0” into bedrock. He said the test pits should be excavated at the east facing cut, at the landslide area and where ever Patrick believes appropriate.
* Frank Rollo said the plan should indicate all fills should be keyed and benched into bedrock.
* Frank Rollo asked the shoring engineer to make changes on sheet SH2.5. He recommended showing drain being connected to the city drain.
* Frank Rollo said the special inspectors should be the geologist and the design engineers for this project.
* John Hom, Structural Engineer, thinks the soil nail system is not a good option for this project. He recommended the design team consider using cantilever soldier pile with lagging; a solider pile system will eliminate encroachment into the neighbor’s property. He also recommended the option of constructing the driveway slab as structural slab spanning between supports.
* Allen Gruen said that Chert could be hard to drill, which would be a concern for the cantilever soldier pile with lagging system. However, he agreed that the design team should consider that option.
* Allen Gruen said he hopes to eliminate any fill on the site and use structural slab spanning between supports with crawl space and rat slab underneath.
* Lou Gilpin said if the design team decide to use cantilever soldier pile system, then a test pit would not be necessary on the east facing side, but would still be needed it at the landslide area.
* Frank Rollo said he needs a letter from Allen providing his recommended design parameters and stating he reviewed the calculations and the drawings. Frank needs a letter from Patrick stating he reviewed the design parameters. Frank asked the shoring engineer to make sure his design is stable. If fill is used, it should be keyed and benched into bedrock; drain pipe should be tied to the city drain; and that he will be the special inspector for all of his excavation. 
* Frank Rollo said that any voids should be filled with lean concrete.
* Frank Rollo said if the design team decide to use a cantilever soldier pile system, it should be incorporating permanent design. The shoring engineer said water proofing would be difficult with this system.
* Patrick asked if he should include recommendations on how to take care of the landslide in his letter. Lou said yes.
* Frank said the drawing should call out the relative compaction. Allen said it is 90% and it is on the soils report. Frank recommended the information be put on the plan.
* Frank said the plan should show how to control surface water.

Next meeting will be on July 7th from 1:00 pm to 3:00 pm. The topic will be “Final Review of Applicant’s Design.”

Meeting adjourned at 3:00 p.m.