The photo shows the new buried seismometer set up at X-end.  Figure 1 shows the signal compared to the building STS. Note that the coherence between the Y-axes is quite low even at 1 MPH. This axis also had low coherence when I huddled it with the PEM seismometer so it is likely noisy. Hugh and I noted that the Y-axis did not seem to go through the centering process when commanded like the other axes. The new Trillium should solve this.

That being said, the important axis is the X-axis. Note that the windy signal from the buried seismometer is, just below 0.1 Hz, at about the same low level as the GND STS.  I doubt that the ground seismometer would help much at this location.  It may be necessary to move it into the depression that the building sits in to make it better than the GND STS. We chose this location for a seismometer to monitor the prototype wind fence, hoping that it would also have less tilt than the building seismometer.  But it looks like we will need a second hole if we are going to use a buried seismometer in a super sensor at EX.

Figure 2 shows data for the EY seismometers for wind speeds averaging 32 MPH. The buried seismometer is at least a factor of two better than the building seismometer along the beam axis, as it was during the several other storms I studied. While we hope that we don’t need to use the buried seismometer at EY because the new EY BRS does even better, I think it is still worth testing it in a super sensor because a buried seismometer may be useful at the corner station or at LLO.