The U.S. government has wasted at least $17 billion in taxpayer money in Afghanistan on various projects that never made it off the ground or were doomed to fail because of incompetence or lack of maintenance in the war-torn country, according to a new report.

ProPublica looked at over 200 audits conducted by the Special Inspector General for Afghanistan Reconstruction (SIGAR) in the last six years and tallied up the costs for the wide range of failed efforts to reach the $17 billion price tag.

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The watchdog office formed in 2008 -- seven years after American military forces entered Afghanistan -- only scratched the surface of the estimated $110 billion effort to rebuild the country. That gap means the amount of wasteful spending is probably much higher.

The new study is like a greatest hits compilation. It recounts the most egregious examples, many of which grabbed headlines over the years, of how Washington threw good money after bad. It includes:

$8 million to end Afghanistan’s drug trade, which by most accounts is flourishing today as never before

$2 billion for roads that the Afghan government is unlikely to maintain due to lack of funds and security concerns

$1 billion for unrealized criminal justice reform efforts

While those initiatives can be laid at the feet of several government agencies, the report notes that the Defense Department is solely responsible for multiple boondoggles, such as $936 million for various aircraft that can’t be maintained and another $486 million for cargo planes that can’t fly.

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The Pentagon also shelled out $470 million on the Afghan Police. The study also notes the $43 million gas station that has roiled Capitol Hill in recent weeks.

The timing of the report couldn’t be better for SIGAR. John F. Sopko, chief of the watchdog office is slated to appear before a Senate Armed Services Committee subpanel shortly after lawmakers return from their holiday break.

The January 20 hearing was ostensibly to scrutinize the work by the Pentagon’s Task Force for Business and Stability Operations, which spent between $700 million and $800 million on economic redevelopment in Afghanistan on projects, like absurdly pricey gas station, as well as $150 million on villas and private security for the group’s staffers.

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But Senators will likely use the ProPublica report as a way to press Brian McKeon, principal deputy undersecretary of defense for policy, about the task force’s work. The group disbanded earlier this year. Pentagon officials have argued, rather absurdly, that there is no one in the sprawling department today with any knowledge of the task force, including how it spent its money.

The new price assessment also gives SIGAR supporters like Sen. Claire McCaskill (D-MO) fresh arguments for keeping the watchdog office around even though the U.S. combat mission in Afghanistan formally ended last year.