As the nuclear crisis at Japan’s Fukushima Dai-ichi nuclear power plant continues to threaten the health of millions of Japanese, the safety of Taiwan’s three operational nuclear power plants and how well managed those plants are has come under greater scrutiny, especially in light of reports that leaks at the Japanese plant may have partly been the result of years of neglect and corruption.
On June 19 last year, the Taipei Times exposed problems at the Guosheng Nuclear Power Plant in Wanli (萬里), New Taipei City (新北市), after a US diving company alleged that staff were treating the suppression pool as a “garbage dump.”
Robert Greenspan, president of South Dakota-based Midco Diving and Marine Services, told the Taipei Times that the pool, which would play a critical coolant role during a nuclear emergency (when the energy produced by the reactor core is greater than the energy removed), had contained inordinate amounts of silt and various foreign objects, such as cable spools, oxygen tanks and masks — all highly radioactive. According to foreign material exclusion rules, any object that is taken into a suppression pool must be taken out, as foreign objects can disturb the flow of water in the tank and cause jamming.
Contracted by Ming Tai (閩台), a Taiwanese firm, Midco conducted underwater maintenance in Unit 2 at the plant in November 2008 and Unit 1 in March 2009. However, Greenspan said there was so much foreign material in the Unit 1 pool that divers were unable to complete their work in the 10 days given them. An ensuing contractual dispute prevented Midco from returning to the site.
Contacted for a follow-up late last month, Greenspan provided more details of the situation back then.
“When we were cleaning, they were still dropping garbage into the pools. We would clean an area and go back through it later, and there would be more debris,” he said. “They also used it as a spittoon for the beetle nut they chew on.”
Prior to Midco, another US diving firm, Connecticut-based Underwater Construction Corp (UCC), had conducted similar underwater cleaning work at the plant’s Unit 2 during the 18th refueling outage in April and May 2007. Contacted in June last year and again last month, UCC did not respond, but the Taipei Times has obtained a copy of the company’s final report on its maintenance work at the unit.
Before the work in 2007, the vent annulus — the area between the reactor’s steel container, or the primary containment structure, and the concrete building surrounding it — at Unit 2 had never been desludged or inspected in the immersion area, the report said. Unit 2 went operational on March 15, 1983. During desludging and inspection, all foreign material found was removed from the annulus and suction strainers.
The sludge in the pool consisted mainly of fine particulate mixed with large amounts of corrosion products from system piping and welding slag, and evidence of fibrous material was noted, the report said. Typical sludge depths ranged from 150mm to 450mm. In all, 50 bags of foreign material, weighing about 9kg each, were removed from the annulus area. The majority of the foreign objects found were identified as tape, wire, welding rods, welding slag and tie-wraps, as well as a tool box with tools inside, a piece of grating, several scaffold poles and a scaffolding platform.