Officials at Japan's earthquake-damaged Fukushima Daiichi nuclear power plant said on Sunday they'd discovered a leak in some new equipment that is supposed to keep radioactive water out of the ocean. Most of the contaminated water stayed in a concrete-lined catchment device, but some of it leaked through cracks in the concrete and into the Pacific Ocean, the company said. The scale of the leak is a lot smaller than the amount of radioactive water dumped into the ocean by plant operator Tokyo Electric Power Company (TEPCO) as it tried to temper a developing nuclear crisis in April. But it's a sign the company doesn't have the plant completely under control nearly nine months after the devastating March 11 quake and resulting tsunami. The Los Angeles Times notes that the leak "counteracts assurances that the Tokyo Electric Power Co., or Tepco, has largely controlled damage at the coastal nuclear plant," and The New York Times points out that TEPCO has said that it hopes to bring the plant to a stable state known as a cold shutdown by the end of the year."

TEPCO said that on Sunday at least 45 tons of water had leaked from a purification system it had installed in September. One ton of water contains about 260 gallons. The Los Angeles Times explains the damaged purification system:

TEPCO installed a new circulatory cooling system in September with filters that decontaminate and recycle the cooling water. But the company acknowledges that some water has already leaked into the ocean, and thousands of tons of water remain in the flooded basements of the plant's reactor buildings.

According to the Associated Press, the company estimates about 300 liters (80 gallons) leaked out of the crack in the concrete barrier and into a gutter that ran to the ocean. In April, when workers were trying to stave off a more severe nuclear catastrophe than what was already underway, the company dumped about 11,500 tons of radioactive water into the ocean. One of the elements contaminating the water in Sunday's leak, cancer-causing cesium-137, can stay in the environment for 30 years, the AP reported.