I joined this forum only to give you news of whom you seek. I knew him in the early 1970's. Arthur J. Hempel, Art, secured a job teaching social studies and West Valley (Junior) College in Saratoga CA in about 1970-1. Since social studies was not what he was teaching in the classroom, Hempel's bid for tenure was challenged by many on the staff and tenure was ultimately denied by the school. Hempel took WVC to arbitration and lost there also.
With a few friends Hempel moved to Boulder Creek and in 1974 established the "Christ Circle" contemplative society. He bought some acreage with livable buildings and a meeting center. Art told me he had acquired public financing to build an "alternative" school for the children of adults of the Circle.
Art, once seemingly a level headed philosopher in the Christian tradition, began to believe in "himself". He was tall, red headed, wireframe glasses, misshaped skull, thick jaw and a club foot... I don't remember which foot. Art seemed to be changing and I didn't like it. I'm not sure how to explain it but I left his company and the few friends I made in the Circle at the time. I wish I could remember some names from so long ago in case that could help you.
A couple of years later I read an article in the Santa Cruz Sentinel about some trouble the Circle was in with the Santa Cruz County and that Art had left the area. I simply do not remember the details. You might try to find the article(s) there through some clipping service, or go to the paper's offices to look at their stacks. Here is a link to the paper's website... www.santacruzsentinel.com/
That's the last I heard of Art until recently.
I found a reference to Hempel on the website: steadfastsail.com/about-us.html
Here is the paragraph mentioning Hempel...
Grace and Laurence have both spent many years practicing meditation, and are members of The Christ Circle, a contemplative community founded in California in 1974 under the leadership of Arthur Hempel, and following the writings of Joel Goldsmith. The other members of the community are engaged in managing Zarephath Wines in Western Australia, and it is intended that they will in due course join Laurence and Grace in New Zealand.
I hope this information helps you to locate your family members and I hope all is well with them. If you do make contact with Grace or Laurence, please let me know what they can tell you about Art. Since I knew him, I am curious about him and his "Circle".
I will remain anonymous for my own safety, please forgive the ruse.