. >> mr. mahan from pennsylvania's recognized for five minutes. >> thank you, mr. chairman and thank you for your presence here today. one of the big concerns of course is not just your work in trying to internally resolve these issues, but the fact that there are businesses and others who are out waiting for the ultimate determination and at time, economic challenge that continues to be a concern. can you talk to me a little bit about the tiering formulas that are taking place and the process by which the tiers were identified and how it resolved itself at least at the first level? >> sir, initially, we identified chemicals of interest in levels of hold that is sites might have to determine whether or not a second look was required. that information was provided as i indicated in my opening statement. 40,000 facilities were identified. >> self-report ed? >>. >> self-reported. >> were there any random checks to make sure there was accuracy? >> the check was the second tiering process, sir, which was a much more details, excuse me, a second assessment, which was a m