The bluing process, like chrome plating, electro polishing and anodizing, which services were available on this island, required large tanks of chemicals. When the EPA got strict on disposing of these chemicals, the chemicals had to be shipped to the mainland for disposal. That is expensive, so no more chrome plating, electropolishing, anodizing and I guess bluing shops on the island. I'm not sure how those businesses were disposing of the chemicals before the EPA stepped in, but it probably wasn't environmentally friendly.