LADWP DS 104 Task Force Meeting
Tuesday 10/30/2012
Report by Jim Rea, Task Force Member
Task Force meeting opened with a request from the facilitator for additional suggestions of sites for consideration.
Gil Dembo mentioned a site at the foot of Bienveneda that has long been offered for sale. A large host of comments came from several members of the Task Force, including that it is subject to large liabilites, it has geological issues (what site doesn’t), used to be a haul dump site, has a history of many slope failures, it is a riperian area, meaning there is flowing water on the site. There was little or no interest from the Task Force in securing additional information about the site.
The facilitor noted that as we get further into the process, we will find it necessary to stop accepting ideas for new properties soon. So if there are any properties needing to come into the discussion, they should be submitted as soon as possible.
We discussed the presentation of sites at the public workshop. Initial materials had only mentioned that Tier 1 sites will be presented to the public. Given concerns from the community that all sites (Tier 1, 2 and 3) should be presented at the workshop, it was agreed that there was no problem in presenting all three Tiers to the attendees. The emphasis in the public workshop will continue to be on the Tier 1 sites, though the public is free to comment on any of the sites.
Some questions were raised about safety at distribution stations around the city. Questions were raised as to whether there were explosions or major fires at any of the 120 distribution stations around the LADWP service area. DWP staff (Eric Hartman) reported that he does not recall any explosions in the past. There have been occasional minor fires as insulation or equipment wears out or overheating of conduit or cable, that can lead to arcing. All of the fires he is aware of are minor in nature. He did report that there have been larger fires at large receiving stations, but they operate at much higher electrical loads with much larger transformers than do distribution stations.
DWP Geologist Jim Chestnut gave a presentation on geological issues and means of mitigation at construction sites. The discussion picked up with the concerns about safety from earthquake damage. Distribution stations are built to the same standard of safety as are schools and hospitals, which is the highest level of safety as mandated by law. All distribution station equipment is tested on shake tables to the maximum ground shaking levels expected in the Southern California area.
Next he discussed the seismic hazard and liquefaction areas in the DS 104 target area of the Palisades. Basically all of the sites will have one form of seismic issue or another. They are a common problem for the DWP and there are reliable mitigation measures that can be applied to address most issues. One thing that slows down the process in the Palisades is the fact that this area was never surveyed for Alquist-Priolo Active Fault maps. Thus, each property under final consideration will have to be investigated to to determine to what extent, if any, active faults exist on the site.
He spoke about the typical mitigation techniques, including setbacks from faults and slopes, use of caissons to create deep foundations, use of retaining walls and debris walls, ground improvement and buttress fill techniques.
The next presentation came from DWP Manager of Environmental Assessment Chuck Holloway about Electro Magnetic Fields (EMF). He explained what EMF is and described some of the common sources of EMF. He showed comparison of EMF from power systems with other sources of electromagnetic radiation including radio, TV, microwaves, ultraviolet, x-rays and gamma rays, demonstrating that powerline EMF operates at the very lowest end of the frequency spectrum. Of the two components of EMF, electric fields and magnetic fields, magnetic fields are more of an issue. Electric fields can be easily shielded. Magnetic fields are more difficult to shield.
He spoke about health concerns in the late 1970’s and revealed that there was never conclusive evidence of causation of health issues with individuals. HIs conclusion was that after 25,000 studies over 30 years, “there is not a strong enough case of cause-and-effect for scientists to conclude tht long term exposure to weak electromagnetic fields is harmful. If there is a risk it is very small”
We had a side discussion with Bill Piazza from LAUSD regarding the practical standards they maintain when situating a school near a distribution station. He said that the state has a standard of 500 feet for facilities with 50 Mv. capacity or more, however distribution stations do not fall under that standard since they operate at 34.5 Mv. He said that ordinarily, when a facility is situated near a power intensive facility they will have a member of the school staff wear a measurement device over a period of several days to determine what the ambient EMF is in the area. Anything over 2 or 3 mG ( .001 Gauss) is cause for investigation.
Contrasting that in Holloway’s presentation, he showed measurements of 3 mG or less beginning at 20 ft. or more from the exterior walls DS-66. He also showed a chart of common household appliances with mG measurements ranging from 5 to 250 mG at a distance of one foot.
There were so many lengthy and detailed side discussions during the course of the evening that the Task Force was unable to get to the detailed evaluation of the next four candidate properties. So this portion of the agenda was deferred to the next meeting.
The next meeting is scheduled for Wednesday, November 14, 2012.
The meeting handouts may be downloaded from the following link:
https://docs.google.com/open?id=0BwkQFPaAN4zwT1A2eVZ6NlJBd28
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