>> jean ngerageze is the president of a local mining cooperative. >> we asked jean how miners here were able to make a living before the site was certified. >> did you have the same system six months ago? >> nyabibwe is the mine that was held up as a model by western companies. >> so before this mine was certified, minerals would be brought there and tagged as if they were part of nyabibwe's production? >> we're in bukavu, the capital of south kivu to meet with abbas kayonga. abbas heads the the anti-fraud division of the ministry of mines here. when we told him we'd heard minerals had been tagged and sold illegally in nyabibwe, he said the site is currently under investigation. >> what can you tell us about incidents of fraud in numbi and nyabibwe? >> so you're saying the amount that's produced in nyabibwe is not very high, but the amount that is exported is very high. >> abbas and his agents track minerals from uncertified mines that arrive in the city. he told us that in the last 7 months they've intercepted 52 tons of illegal tin. he took us to a boat landing along lake kivu, one of