CGMPs in a feed mills for animal feed

I am just curious if anyone else out there is trying to determine what words like adequate actually will mean to an FDA auditor when it comes to the cleanliness of a feed mill facility that deals primarily with dry ingredients? 

I was dealing with a similar situation in my feedmill but found that no swabs are necessarily needed and that as long as you and your team decide that the PrP's in place are being done on a scheduled basis and cross-contamination is mitigated to some extent, we weren't harassed too much concerning the cleanliness of a feedmill. In my experience (we are a dry ingredient poultry mill), our auditors expect a certain degree of dust build-up but as long as there is a master sanitation schedule in place and this schedule is being followed accurately and a qualified individual is verifying and validating the completion of each task, the auditors are happy. 

that was my understanding as well. We are pretty small mill and i just didnt know what others have been through. Thank you