"Afghanistan is a very difficult place to work. We put our lives on the line for the government and the people of Afghanistan every day and we are proud of the work we've done in the region," the company said in a statement.
The plant typically runs at less than 10 percent capacity, according to USAID. Sheikeb Nesar, the head of operations for Afghanistan's national power utility, said the plant was used only during emergency situations when other power sources to Kabul were cut off.
"It is a big, hulking, overpriced, oversized generator, and you don't pay almost $300 million for a generator," McCaskill said.
But the senator defended Black & Veatch, a company that contributed $6,000 to her campaign in 2006 through its political action committee, and $1,000 in 2008. The PAC didn't donate to her 2012 campaign.
"They didn't do anything wrong," McCaskill said. "What was wrong was the analysis in the first place. . There was not an adequate sustainability analysis prior to the decision to build it."
Such an analysis is mandated by the new law, which should help prevent flawed ventures such as the plant, McCaskill said. The law requires government agencies to prove that taxpayer dollars won't be wasted on futile or ill-conceived projects before they allocate funds, strengthens the powers of inspectors general who investigate cases of fraud and abuse, and establishes a clear chain of authority for contracting oversight in the Defense Department, the State Department and USAID.
"Now someone has to take responsibility for the contract at the front end, so that if things go badly we know who to call on the carpet," McCaskill said.