Yes, the site is undeveloped. I have been told by several sources that NFPA allows the shell to shell tank spacing to be reduced when the tanks are protected by water spray or insulated, etc. But I can't find this anywhere in NFPA 15. I had been told that NFPA 30 references NFPA 15 for that...
I am currently trying to squeeze 6 million barrels of various Class flammable/combustibles onto an existing undeveloped rural site. I see in the NFPA 30 that for floating roof tanks whose diameter is larger than 150ft, and that contain Class IIIa liquids, then the spacing must be 1/4 X (sum of 2...