TEPCO fears that the power supply equipments in the basements may degrade from the salt water from tsunami, but if they have been sitting in the salt water for nearly 3 months, they are practically worthless, I would assume.
Again, a brilliant design by GE, having the power supply in the basement in a nuclear power plant right by the ocean in an earthquake/tsunami-prone country.
From Japan's TBS News (10:58PM JST 6/7/2011; the link will probably be changed or disappear soon, as is often the case with the TV broadcasters):
東京電力が、福島第二原発の原子炉建屋などに溜まっているおよそ３０００トンの水について、海に放出する計画を立てていることが分かりました。ただ、海産物への影響を懸念する農林水産省が猛反発していて、調整は難航しています。
It has been revealed that TEPCO wants to release about 3,000 tons of water in the reactor buildings [and turbine buildings, according to the news clip at the site] of Fukushima II Nuclear Power Plant. However, fearing the negative effect on marine products, the Ministry of Agriculture, Forestry and Fisheries is strongly against the plan, making the negotiations between TEPCO and the Ministry difficult.
福島第二原発の原子炉は現在、冷温停止中ですが、震災で津波を被り大量の海水が原子炉建屋やタービン建屋などに溜まったままとなっています。このため東京電力は、大量の水を海に放出する計画を立て、政府関係者とすでに協議していることが分かりました。
The reactors at Fukushima II Nuke Plant are in "cold shutdown". But the tsunami after the March 11 earthquake inundated the reactor buildings and the turbine buildings. TEPCO planned the release of this large amount of water into the ocean, and has been negotiating with the government officials.
塩分を含んだ水の量はおよそ３０００トンに達すると見られ、溜まっている期間も長引いているため、このままでは建屋の地下にある電源装置が劣化する恐れもあります。
This salt water is estimated to be about 3,000 tons. Since it has been sitting in the basements for long time now, the power supply equipments in the basements may degrade
この水について東京電力は、法律で認められているより低いレベルにまで放射能の除染を済ませた上で海に放出すると説明していますが、海産物への影響を懸念する農林水産省が猛反発し、調整が難航しています。（07日22:58）
TEPCO says it will remove the radioactive materials in the water to the level lower than allowed by law before releasing it into the ocean. But the Ministry of Agriculture, Forestry and Fisheries is strongly against the plan, fearing the effect on the marine products.