Bruno Tisserand Thierry Trotouin, Christelle Pagotto

1. Feedback Experience on the Reduction of the Chromium Discharges (Tanners) in the Sewer Systems of the city of Millau (Aveyron - France) Bruno Tisserand Thierry Trotouin, Christelle Pagotto Veolia Water - CONFIDENTIAL

2. Summary 1- The problem 2- The approach a- Identification of the potential sources in the perimeter b- Measurement campaigns on the network c- Search for solutions and advices to the industrials 3- The results a- At the industry level b- At the WWTP level Veolia Water - CONFIDENTIAL

3. The problem Agricultural use of sludges … WWTP Millau : 65 000 EH … but frequently exceeds threshold for chromium (1000 mg/kg DM) that prevent Sludge recovery! Veolia Water - CONFIDENTIAL 02/10/2014

4. The approach • A three steps appraoch … Step 1 : Identification of the potential sources in the watershed Step 2 : Measurement campaigns on the network Step 3 : Search for solutions and advices to industrials Veolia Water - CONFIDENTIAL

5. Matrice [Substance  Secteur d’activités] • Données SIRENE + Données Exploitant • Administratif (Codes NAF, nbr de salariés…) • Technique (Raccordements, Consommation…) STEP 1 : identification of the potential sources in the watershed Use of the Actipol tool (internal Veolia tool) • Matrix [Substance  Activity sector] • SIRENE data + Operator data • Administrative information (NAF/NACE Codes ; nbr of employers, …) • Technical information(Connection to sewerage, water consumption, …) Veolia Water - CONFIDENTIAL

6. Activities related to the use of chromium - Millau (Actipol) : - Activity pre-press - printing - Tanning and dressing of leather - Laundry /drying - Manufacturing plastic packaging - Manufacturing / finishing of textile articles - Surface treatment STEP 1 : identification of the potential sources in the watershed => 34 industries identified In the sector Veolia Water - CONFIDENTIAL

7. Matrice [de salariés…) • Technique (Raccordements, Consommation…) STEP 2 : Measurement campaigns on the network • Identification of sampling points according to the catchments • Automatic samplers : 24 h samples, during 10 days (april 2011) : conductivity, COD, TSS, Cr total Veolia Water - CONFIDENTIAL 02/10/2014

8. Matrice [de salariés…) • Technique (Raccordements, Consommation…) STEP 2 : Measurement campaigns on the network COD (mg/L) Conductivity (µS/cm) • Significant release on 2/3 zones that have to be investigated deeply : Pechdo and les Fialets Cr total (mg/L) TSS (mg/L) Veolia Water - CONFIDENTIAL

9. Matrice [de salariés…) • Technique (Raccordements, Consommation…) STEP 2 : Measurement campaigns on the network New campaign (June 2011) : two main contributors identified : - Tanner N°1 - Tanner N°2 (C>>>>>Authorized thresholds by the agreement). => Able to explain fluxes observed on the WWTP ! => Monitoring and audit of the pretreatment of the Tanner N°2 recommended ! Comparisonbetweendischarged fluxes and inlet of the WWTP Veolia Water - CONFIDENTIAL Veolia Water - CONFIDENTIAL 02/10/2014

10. Matrice [de salariés…) • Technique (Raccordements, Consommation…) STEP 3 : Search for solutions and advices to the industrials • Writing of an amendment to the agreement (between Tanner N°2 and Millau City) to modify certain points : • Obligation to modify the pretreatment to assure the compatibility of the discharge with the defined thresholds • Frequency and nature of the control to be done, … • Optimise the pretreatment on site :- Moving the coagulant injection point in the buffer tank,- Establishment of a flocculation tank between the buffer tank and settling,- Revision of failed automation (valve for sludge extraction) or replacement of the valve by a sludge pump, • - Follow strict daily operation (pH control, …), • - Maintenance of equipment (cleaning or renewal of the press filter, sensors...), - … 02/10/2014 Veolia Water - CONFIDENTIAL Veolia Water - CONFIDENTIAL

11. The results • At the industry level (Tanner N°2 ) • A significant improvement is observed … • But, concentrations remain above the threshold (1,5 mg/L) even if fluxes are below the threshold (<0,45 kg/j)=> Due to the limits of the existing treatment Veolia Water - CONFIDENTIAL

12. The results • At the WWTP level • Also a significant improvement … • But results should always be good: complementary solutions are necessary … • - additional equipment to control the sludge release • - materials recovery : reuse the garbage fullers as raw material for chromium recovery in the initial process Veolia Water - CONFIDENTIAL

13. Measures under discussion • Additional monitoring by external consultant on treated waste water discharge as well as on Tanneries WW pre-treatment operation • Establishment of a bonus-malus depending on the quality of the results • Proposal for an "ECO-TANNERY" label (based on environmental footprint, Water Impact Index, Carbon Footprint …) • New monitoring campaign on the network with Octopus (passive sampling) Veolia Water - CONFIDENTIAL

14. Conclusion • A first and significant improvement has been reached by reducing the major chromium source resulting in both a better sludge and water quality • Next step will be to look for other sources in order to reduce minor chromium discharges • Municipal authorities are in agreement with this long term and cooperative strategy between industrials, Veolia and the city of Millau for a sustainable Chromium reduction in municipal sludge Veolia Water - CONFIDENTIAL

15. bruno.tisserand@veolia.com Thank you for your attention Veolia Water - CONFIDENTIAL