Emergency Services, Office of
(Office of Emergency Services, California)
Seismic Monitoring Station
NOE - Notice of Exemption
This new station will contribute to the CA Earthquake Early Warning System (CEEWS) designed to potentially save thousands of lives during a large earthquake, prevent critical infrastructure damage and expedite recovery following a large earthquake. The network to which this sensor is connected will contribute real-time data to accurately record and warn people of strong shaking due to earthquakes in the region, and help provide records of ground motion that would be immense scientific, engineering and public safety value.
Under a ten-year lease with property owner, UC BSL plans to install and operate an outdoor seismic monitoring station at the Lat/Long location noted above. Three-day installation will take place in a roughly 36-sq. ft. area, to install two structures: 1. 4'x3'x10" sensor vault set on a 6" concrete base, with two attached PVC-pipe postholes (10" diameter) running from center of vault, to a maximum of 10' into the ground, leading to two seismometers (1 strong motion accelerometer and 1 broadband seismometer); 2. 4'x3'x6" concrete base on which a battery box, solar panel equipment, antenna mounts, and communications equipment are housed, and 3. 10'x15'x5" fence around site, with fence posts placed 1' deep in 4" diameter holes. A flexible conduit 1' deep and 5" wide will connect the two structures. Grounding rods will be inset next to the equipment to protect the site from lighting strikes. Holes for the vault, solar panel mount, and antenna and fence poles will be dug by a small backhoe or hand-operated auger. Access to site is entirely by existing roads and trails. There are no hazardous substances involved. If needed, a small generator (~8 KW) will be used to power a hand-loaded concrete mixer and any other tools needed for the work. A detailed description, schematic and photos are in Attachment 1.
This project is exempt in accordance with Class 3 as described above; construction of new small weatherproof enclosures to operate seismic sensor equipment for the purpose of data collection (Class 6). In accordance with Class 4, the project described above consists of minor public or private alterations in the condition of land and/or vegetation which do not involve removal of healthy, mature, scenic trees. None of the exceptions to a notice of exemption apply.