We have a vacation home that sits idle from October to March each year. The well was drilled in 2007 and only used one weekend before sitting all winter. When we arrived in april of 2008 the water was very dirty and smelled terrible, we were told by drilling company we had an iron eating bacteria and that we had to sanitize the system with bleach. We did this (twice) and the water came out dark orange for a very long time, but eventually it was clear enought to wash dishes and shower. All seemed OK except for a rotten egg smell which we were told was sulfides. (Water was tested - high iron and yes sulfides). We were willing to live with this and just used bottled water for cooking and drinking. Well fast forward to 2009, turned everything and and the water was dark brown, like mud. Here we go again... We've encountered the same thing all over again, bleached the system and the water ran clear but then went back to a light brown after a little while. We've talked to Laboratories, the well drilling company, and are at witts end on what to do. The lab says go to the drilling company - the drilling company says no guarantees on water quality. I'm not so sure it's all quality - since it was ok last year until it sat over the winter. One note - the main pipe to the well only has a loose cap over top of it. Any thoughts or ideas would be greatly appreciated.