The binary data are available by station via anonymous FTP from the National Strong Ground Motion FTP-server:
https://ca.water.usgs.gov/nsmp/ in directory GEOS/DIL.
For further information on these recordings refer to USGS Open-File Report 89-349: Borehole Dilatometer Installation, Operation and Maintenance at Sites Along the San Andreas Fault, California; by G. Doug Myren and Malcolm J. S. Johnston.
The GEOS Home Page is at /GEOS/geos.html
The URL of this page is /GEOS/DIL/dilatometer.html
e-mail: glassmoyer@usgs.gov
or address:
Gary Glassmoyer
345 Middlefield Road M/S 977
Menlo Park, California 94025