PASO ROBLES, Calif. (AP) — Scientists seeking to put seismic sensors deep in the San Andreas fault to study the mechanics of earthquakes are in danger of losing their funding.

The San Jose Mercury News reports that the National Science Foundation has said it is no longer soliciting proposals for experiments connected to the endeavor.

The project site is near the rural, unincorporated Monterey County community of Parkfield, which is about 30 miles northeast of Paso Robles.

Scientists have already spent $25 million drilling one borehole there. But the Mercury News says they still need millions more to install a permanent observatory in the ground and drill a second hole.

The National Science Foundation's James Whitcomb says the agency will review its decision to stop soliciting proposals for the site in the winter.