Dear All, We're using a YSI Pro plus meter for parameter stabilisation on low flow sampling and we continually getting negative readings on all of the wells on a gasworks site bar one where it was 255. The question is, why do you get negative readings and what are they representative of. Answers from competent persons only please. RMack. Robin Mackenzie Land Quality Team Co-ordinator The Environment Service Perth and Kinross Council The Atrium 137 Glover Street Perth PH2 0HY [log in to unmask] Mob: 07810057566 Tel Direct Dial: 01738 476443 Fax: 01738 476410 Securing the future... - Improving services - Enhancing quality of life - Making best use of public resources. The information in this email is solely for the intended recipients. If you are not an intended recipient, you must not disclose, copy, or distribute its contents or use them in any way: please advise the sender immediately and delete this email. Perth & Kinross Council, Live Active Leisure Limited and TACTRAN do not warrant that this email or any attachments are virus-free and does not accept any liability for any loss or damage resulting from any virus infection. Perth & Kinross Council may monitor or examine any emails received by its email system. The information contained in this email may not be the views of Perth & Kinross Council, Live Active Leisure Limited or TACTRAN. It is possible for email to be falsified and the sender cannot be held responsible for the integrity of the information contained in it. Requests to Perth & Kinross Council under the Freedom of Information (Scotland) Act should be directed to the Freedom of Information Team - email: [log in to unmask] General enquiries to Perth & Kinross Council should be made to [log in to unmask] or 01738 475000. General enquiries to Live Active Leisure Limited should be made to [log in to unmask] or 01738 454600. General enquiries to TACTRAN should be made to [log in to unmask] or 01738 475775. Securing the future... - Improving services - Enhancing quality of life - Making best use of public resources.