[Rhodes22-list] Cracks in Cement Ballast

[E.Andler]

Hi All:
I recently found a 1983 R22 for sale that I was told that under the
floor boards the cement ballast had cracks in it.
How and why does this happen? Is it a common occurrence, even in newer
boats?
Should it be sailed as is, or has this become a project boat?
If it's a project boat, what would be involved in repairing it?
Thanks in advance for the info.
Ed