for this american land, i'm gary strieker. reactor building on tuesday to drill a hole. spokespersons y workers were exposed to up to three millisieverts of radiation during the drilling process. 40 workers rehearsed the job at the plant's number five reactor to minimize their exposure. tepco spokespersons say the operation went smoothly. workers will insert the endoscope on thursday as scheduled. tepco is boosting electricity rates for its corporate clients. the utility says the rates will go up an average 17% beginning in april due to rising costs for thermal powered generation. tepco president attorneyio nishizawa said on tuesday that the hikes will affect business users with contracts for 50 kilowatts or more each. the company's fuel costs for thermal power generation are expected to climb by about $10 billion this fiscal year. that's because utility has shut down some nuclear plants for checkups after the fukushima accident last march. tepco says higher electricity bills are unavoidable because it's not clear when the operation of these nuclear plants will resume. >