The minutes of the 3rd meeting of the heads of the labs in Arcachon, France, June 2011 are now posted on the page of the Working group QA/QC in labs. Also all presentations of the meeting can be found there. The new excel file for the validation of analytical data (with DOC and Al, Fe and Mn) and an excel file for the calculation of alkalinity is also posted on the page (see under "quality assurance and control in Laboratories")