While installing a new valve for a ice maker in our galvanized steel pipes I (slowly) noticed that i was being shocked. At first i just thought that turning the wrench was making may hand and wrist ache, but as my hand got wetter it got to the point that it was really shocking me good. The valve was wet, the ground (crawlspace) was wet and i was laying in the puddle while working on the pipe. This house is over 80 yrs old and i know that the electrical grounds to the plumbing at many different points. Is this okay? not sure if this is expected or if it's a sign of something wrong.