Environmental and geotechnical acceptability of alternative material as road construction material Methodological guide

Transcription

1 Environmental and geotechnical acceptability of alternative material as road construction material Methodological guide Laurent CHATEAU ADEME (French Agency for Environment and Energy Management) Waste & soil Directorate

2 Presentation outline Context Methodological guide Objective Scope Principle Methodology overview Environmental characterization Conclusion ADEME Laurent Chateau WASCON 09

3 Context Waste recycling in construction is a historical practice Local scarcity of natural resources Availability of mineral industrial waste Lot of background knowledge on mechanical & geotechnical characteristics ( fit for use ) Environmental criteria are generally missing 2 documents MSWI BA (guideline) Foundry sands (ministry order) phenol index only Criteria not developed under risk assessment basis Heterogeneous situation leading to local difficulties and heterogeneous decisions Plead for an unique & homogeneous framework

4 Objective Provide a methodology to assess the geotechnical & environmental acceptability of alternative material as road construction material Set procedures, tests and criteria Limit values Other requirements Define exclusions and cases when further investigation can be done to conclude Made it possible thanks to: Background knowledge (François et al, 2009) Standardization progress (EN 12920, leaching behaviour tests) Various attempts to work out environmental acceptability criteria in France since a decade (Chateau, 2007) Regulation existing in other European countries (NL, Dk, B, Fi, Es) Decision 2003/33/EC (admission procedure & criteria of waste in landfill)

5 Scope Materials Granular material used as such or as filler or as binder Material can be treated or mixed to fit to specific geotechnical requirements and not to fit to environmental ones Exclusion: entire tyres, material elaborated from dangerous waste Uses Road applications: road-based (2), sub-base(3), sub-grade (4) Capped embankment: shoulders, landscaping (5)

6 Step 1 Waste Step 2 The acceptability methodology is based Geotechnical on current geotechnical (sieving, crushing, iron Alternative Material Road Material Possible Step 3 preparation X removal, etc.), and/or characterization Step 4 Environmental characterization practices ageing Possible formulation (ex : bituminous binder treatment) Step 5 Full scale validation ADEME Laurent Chateau WASCON 09 Road material use Route

7 Methodology overview Geotechnical assessment Compliance with standards developed under the CPD or with specific technical guides Environmental assessment OK OK? Acceptance criteria in inert waste landfills Limit values of the «acceptability» guide 2 set of limit values for acceptability assessment: Road application Capped embankment For waste complying with admission criteria in inert waste landfill: Exemption of step 4 & 5 Environmental procedure based on inert waste landfilling regulation (basic characterization, compliance testing, criteria) Exclusion of dangerous waste Forbidden: Dilution/treatment to comply with limit values ADEME Laurent Chateau WASCON 09 Hazardous waste Hazardousness

8 Environmental procedure overview 2 levels Basic characterization Criteria : Release: percolation test CEN/TS for granular material and pren15864 for monoliths Total content: organic parameters (decision 2003/33/CE inert waste) Other requirements: Batch leaching test EN for compliance purpose Chemical composition Frequency: once every 2 years Compliance testing Batch leaching test EN Material production Continuous Discontinuous Frequency Frequency corresponding to the lower value between once a month and once every 3000 metric tons Case of batches < 3000 metric tons 3 compliance tests Case of batches < 3000 metric tons 1 compliance tests every 1000 metric tons

9 Environmental limit values 2 types Release : metals, salts, ph Total content : organic compounds (PAH, PCB, TOC, BTEX, mineral oil +dioxins/furans for thermal process residues) Release Specifically determined values by modelling Concentration Cumulated released quantity Modelling: Consistency with the work done at the European level for the acceptance in landfill (directive 1999/31/EC ; decision 2003/33/EC) (Hjelmar et al., 2001) Specificity due to the scenario Environmental objectives: Comply with «drinking water quality» for groundwater downstream the road Cap the allowed Cumulated released quantity Avoid to increase the geochemical background Total content Limit values for acceptance of inert waste in landfill (decision 2003/33/EC) Dioxins/furans: background information on MSWI BA and soils

10 Limit values on release Calculation of acceptable concentration C acc (i) at the edge of the road for the element i: Output of the modelling: C POC the concentration calculated at the chosen point of compliance (20m) (see presentation of Bellenfant et al., this conference) Parameter needed: attenuation factor FA ; FA = C POC /C(i) With C(i) is the concentration of the given element i used to calculate C POC C acc (i) = FA x C obj (i) With C obj (i) is the drinking water quality of the given element i Calculation of the cumulated released quantity Q(i) Requirement : in field, the emitted flux shall decrease toward a low constant steady state Base of calculation: concentration C(i) (calculated with a contant source term) (Guyonnet et al., 2008) Method of calculation : for a L/S ratio of 10, the allowed cumulated released quantity shall be 50% lower than the the one calculated with a constant release: Q(i) = 50% * L/S 10 * C(i)

11 Conclusion This guide will provide the long awaited methodology to assess the environmental acceptabiliy of alternative material in road construction The application of this methodology will leads to operational guide dedicated to a given waste stream Currently under progress: C&D waste, MSWI BA Each operational guide will be a sound basis for endusers: Help public works companies to prepare, test and sell alternative material with suitable environmental properties Increase the confidence of contracting authorities is the environment-friendly character of alternative material put on the market

12 Thank you for your attention Literature cited: François D., Jullien A., Kerzreho J.P., Chateau L. (2009) Full-scale experimentations on alternative materials in roads: Analysis of study practices. Waste Management, Vol 29, Issue 3, March 2009, pp Chateau L. (2007) Environmental acceptability of beneficial use of waste as construction material State of knowledge, current practices and future developments in Europe and in France. Journal of Hazardous Materials, Vol 139, Issue 3, 31 January 2007, pp Hjelmar O., van der Sloot H.A., Guyonnet D., Rietra R.P.J.J., Brun A., Hall D. (2001) Development of acceptance criteria for landfilling of waste: an approach based on modelling and scenario calculations. Sardinia 2001 proceeding, vol III, pp Bellenfant G., Guyonnet D., Vaillant P., Chateau L., Méhu J., Leray F. (2009) Groundwater impact simulations for establishing criteria for the recycling of alternative materials in road construction. Wascon Guyonnet D., Bodénan F., Brons-Laot G., Burnol A., Chateau L., Crest M., Méhu J., Moszkowicz P., Piantone P. (2008) Multiple-scale dynamic leaching of a municipal solid waste incineration ash. Waste Management, Vol 28, Issue 10, 2008, pp