Is there any reason to assume the burn, under these conditions, would be complete enough to fully consume the product such that there would be zero danger to

Is there any reason to assume the burn, under these conditions, would be complete enough to fully consume the product such that there would be zero danger to the environment? These are guys on a side of a track ostensibly just winging it. I think it's reasonable to assume the "under laboratory conditions" assessment might not completely apply to this scenario.