Not exactly sure where it’s located, but found a post on the ThaiVisa forums saying it’s a few kms off of highway 36, about 15kms out of town.
Here’s a little information about it – info
Supposedly it’s for prisoners serving less than 10years.
Pattaya Remand Prison
Looks pretty from the outside 
Yes” looks pretty from the outside.. Well its all a Smoke screen, to what it looks like and operated, Inside” And it Very ugly, they make out in the press that they had a large contriband push to clean the place out of Drugs and weapons, they ned to look in there own back yard, because when I was in there it was the personell running the place that was selling the stuff at extorted rates, they are bigger criminals than the people they Subject to mental torture, place should be bombed with the corrupt officials locked in it, the self titled commanders (adi amin’s)
who are corrupt to the hilt. “Like the rest of Thailand”