What is the sive of Blue Lagoon Iceland?

I assume you mean "size" instead of "sive." In any event, 25 yrs ago I was stationed at Keflavik Naval Air Station (co-located with the international airport), which is about 2-3 miles from the "Blue Lagoon," & at that time the Blue Lagoon was about 1/4 of an acre in size. Fortunately for us, it had not yet been commercialized & so we could go there for free at anytime, literally 24/7. Of course a clear night during the middle of winter was the most enjoyable time to go, especially when we wanted to see the Northern Lights. The most memorable of my 10-15 "lagoon runs" always began as someone's post-midnight spur-of-the-moment whim, with at least a dozen culprits participating -- all of whom, except the designated driver (many thx Jim boy!), had downed at least a 6-pack as insulation against the biting cold wind & as a much-needed anesthetic for the shredded bare feet that carried us across a make-shift parking lot created from razor-sharp volcanic rock. As it is with all natural resources of value, I suppose that commercial development of the Blue Lagoon was inevitable & it began about the time I returned to the U.S. in mid-1986. As part of this process the size of the Lagoon could have been increased, or perhaps even decreased after I left. One bit of info I wish to give everyone is this: If you EVER suffer from a severe or persistent fungal disorder then GET THEE TO THE BLUE LAGOON! For the 6-7 yrs immediately prior to my arrival in Iceland, I suffered just such a fungal disorder on my left thumb. But midway thru my 13-month tour of duty at Keflavik, this disorder had cleared up completely & it NEVER returned! I credit the miraculous properties of the Blue Lagoon's unique white mud for this result & I brought a small jar of this strange but wonderful compound with me back to the U.S. just in case that damned disorder ever returns.