Geotechnical Field Work: Beverly Hills Area
Metro contractors are preparing to conduct a series of geotechnical field tests in the Beverly Hills area as a part of the Final Environmental Impact Statement/Environmental Impact Report (Final EIS/EIR) for the Westside Subway Extension. This work will build on the data gathered during the Draft EIS/EIR for the project and provide further soil and seismic information along the route of the Locally Preferred Alternative (LPA). In certain areas, noise and vibration tests will also be conducted. Following the tests, the data will be analyzed and used to make further informed decisions about subway construction.
Monday, October 10 – Friday, October 14, 2011; and
Monday, October 17 – Friday, October 21, 2011
Metro contractors will conduct work on Wilshire Blvd between S. Gale Drive and S. Hamilton Drive.
Note: Should any work need to be cancelled and rescheduled, Metro will inform you of new work date(s)/time(s).
The equipment to be used during the field testing is described below:
Continuous Core Drilling
Continuous core drilling will consist of two methods: hollow-stem coring and rotary coring. Hollow-stem core borings will be drilled using a truck-mounted drilling rig advancing a core barrel into the ground by spinning a 6- to 8-inch diameter casing with a drill bit into the ground to collect samples of the various soil layers. No drilling fluid will be used for hollow-stem coring. Rotary core boring operations will consist of a truck-mounted drilling rig advancing a core barrel into the ground while circulating drilling fluid through the hole, similar to rotary-wash drilling. After the exploration is completed, the soil cuttings generated and slurry used during drilling will be placed in drums, tested for adverse chemicals, and disposed of off-site on a daily basis. As for all borings, the work areas will be scanned for utilities prior to drilling, and the upper soils will be hand augered. At the conclusion of drilling, the hole will be filled with grout and its top patched with asphalt to match the surrounding grade. There will be two to three support trucks for the drilling process. Parking lanes and traffic lanes will need to be coned off during work.
What to Expect During Continuous Core Drilling:
- A drilling crew consisting of up to 4 personnel per rig.
- A truck-mounted drill rig and support trucks (see photo).
- For rotary core drilling, a wash tub to collect and circulate drilling fluid at ground surface during drilling operations, and drums to contain drilling fluid for sampling and disposal at conclusion of drilling.
- For hollow stem drilling, drums to collect soil cuttings for sampling and disposal at conclusion of drilling.
- Parking lanes and/or one to two lanes of traffic will be blocked while work is under
way on residential streets and up to two lanes on business/arterial streets.
- Moderate noise and moderate vibration.
- Lanes will be cleared at the end of the work period and re-opened for regular use.
Other Important Information:
- All work has received necessary permits and approvals.
- Additional fieldwork following this testing is anticipated. We will inform the area(s) where and when this work will take place.
- For more information about the Westside Subway Extension, please leave a message at 213.922.6934 or online at www.metro.net/westside.
- For day-to-day testing location updates, please follow us at twitter.com/westsidesubway .
- For emergencies or issues needing immediate attention, please call 323.236.2117