Possible catchment scale solutions to contaminated sediments in the Elbe River Ulrich Förstner Department of Environmental Science and Technology Universtiy of Technology, Hamburg-Harburg, Germany curriculum in natural environmental science, 2005

Sediment Problem Solutions at Catchment Scale: Overview Location of In-Place Pollutants in a River Basin (Förstner et al. 2004)) Air emissions Mine Wet or dry fallout City Sewage treat- ment plant Old chemical dump site Floodplain soils and sediments Landfill Farm Small Harbors – e.g. Hitzacker Subaqueous Depot & Capping Mine Flooding/Waste In-Situ Treatment Floodplains – e.g. Spittelwasser In-Situ Stabilization (Plants, NA) Location of in-place pollutants Lake Siltation in reservoir Dam Confined dis- posal area for dredged spoils Open dredge spoil disposal area Mine drainage River Dam – e.g. Mulde Temporal Retention I III IV II Harbor basins curriculum in natural environmental science, 2005

Substances and Areas of Concern in the Elbe River Catchment Substance of ConcernHistorical SourcesAreas of Concern arsenic (As)browncoal miningMulde cadmium (Cd)browncoal mining, smelting processes,metal processing Mulde (Havel) (Elbe downstream of Magdeburg) copper (Cu)artificial silk production copper-processing industry Elbe Saale mercury (Hg)chlor-alkali electrolysisSaale, Mulde downstream of Bitterfeld lead (Pb)mining, smeltersSaale, Freiberger Mulde zinc (Zn)industrial and municipal waste- water, mining industry, smelters Saale, Mulde, Weiße Elster, Havel (Elbe downstream of Magdeburg) haloginated organic compounds (AOX) pulp and paper millsMulde, Saale insecticids, DDT, γ-HCHproduction facilitiesBilina (CR), Mulde hexachlorobenzenechemical industryKarlsberg & Luznice (disposal sites), Bilina (CR) PCBchemical industryBilina (CR), Mulde, Saale, Weiße Elster PAHincomplete incinerationSchwarze Elster, Mulde Table 1 Examples of Historical Contamination (S. Heise after Spott & Becker, Prange et al. 2000) curriculum in natural environmental science, 2005

Elbe River Acid Neutralizing Capacity Specific Surface Area Fly Ash29 mMole/g10,3 m 2 /g Red Mud3,25 mMole/g27,8 m 2 /g Calcium Bentonite 0,56 mMole/g55,1 m 2 /g Zeolite0,005 mMole/g15,0 m 2 /g Mulde- Reservoir First PhaseSecond Phase In-Situ Treatment of Mine Effluents with Reactive Materials Upper Elbe Basin – Metal Mobilization from Mine Flooding (Zoumis et al., 2000) curriculum in natural environmental science, 2005

Flooding of Dyke Foreshores Mining Accidents Usual Measures Analysis of pollution load in soils, sediments and groundwater; temporal restrictions to use the sites for agriculture etc. Flood Events Guadiamar 1998, Baia Mare 2000 Floodplains and marshy lands as sinks for contaminated sediments Rhine 1992, Odra 1997, Elbe 2002 Floodplain Soils and Sediments: Examples and Usual Measures Spittelwasser Creek und Mulde River Dioxins/Furans [ng PCDD/F / kg] Village Greppin up to ng/kg Village Jessnitz up to ng/kg Mulde Floodplain up to ng/kg River Bank up to ng/kg Spittelwasser Floodplain (Chemical Triangle) – Dioxins in Soils and Sediments curriculum in natural environmental science, 2005

Proposed Project Estimated Costs/Time 01Monitoring System Detection of the flood-dependent pollutant transport behaviour shall be monitored by hydromechanical methods and air-based systems 400,000 EURO 1 st – 48 th month 02Regulation Project (1)Implementation of models for sediment and pollutant transport (2)Installation and use of sediment traps; point excavation of soil (3)Utilization of „natural attenuation“; promotion of plant growth Projects (1) + (3) 530,000 EURO 12 th – 30 th month 03Testing This refers notably to the functionality and the effects of sediment traps. The results shall be used for predicting the pollutant output 250,000 EURO 30 th – 40 th month 04Permanent Operation (a)Efficiency control of the complete implementation, e.g. by GIS (b)Establishment of citizens‘ advice bureau (children, hunter, etc.) 770,000 EURO 24 th – 48 th month 05Efficiency Control The after-case shall be carried out continuously and long-term according to the example of other permanently observed areas 225,000 EURO (15,000 EURO/a ~ 15 years) Floodplain Soils and Sediments: Interdisciplinary Approach Table 2 Combination of Monitoring Systems, Mearures, Testing and Control (Anon., 2000) curriculum in natural environmental science, 2005

Cause (Example) Effect CompactionReduction of Matrix... Consolidation- Erodibility Phytostabilization (Plant Roots)- Permeability Penetration into Dead-End Pores- Reactivity Interlayer Collapse of Clay MineralsReduced Pollutant... Coprecipitation (High-Energy Sites)- Mobility Occlusion and Overcoating- Availability Absorption/Diffusion- Toxicity ”Diagenesis“”Natural Attenuation“ Floodplain Soils and Sediments: Natural Attenuation Processes Table 3 Demobilization of Pollutants in Solid Matrices by Natural Factors (Förstner, 2003) curriculum in natural environmental science, 2005

Aqueous phase concentration (mg/L) 0,01 0, , ,000 1,000,000 0,0010,010, , Water quality criterion of 1,4-dichlorobenzene (FCV*1000) Predicted SQC with irreversible model Predicted SQC with equilibrium model Solid phase concentration (µg/g) Natural Attenuation of Organic Pollutants – Example: 1,4-DCB Implication of Irreversible Adsorption on Sediment Quality Criteria (Chen e al., 2000) curriculum in natural environmental science, 2005

Implementing remedial actions: Contractors Authorities: Stakeholders: Federal Federal Environmental Agency Fed. Agency Nature Protection Biosphere Administration Environmental Groups (NGOs) Communities External Experts County Ministry of Environment District Administration Landowner Regional Organisations Organisations represented in a remediation working group Large Scale Sediment Remediation: Organisational Aspects Organisations Involved in the Bitterfeld Case (German Legislation; Anon., 2000) curriculum in natural environmental science, 2005

Types and Characteristics of Subaqueous Depots (NL) Type of depotAdvantagesDisadvantages Excavation (pit) type of depot reduced conditions not visible simple fill up less maintenance cost intensive dig off superfluous sand (?) contamination of surface waters special filling equipment no regulation of water level Dike (ring wall) type of depot reduced conditions less cost-intensive dig off less contamination of surface waters easy regulation of water levels easy management and control of emissions visible obstacles for navigation and fisheries more difficult fill up (compared with pit depot) Table 4 Advantages and Disadvantages of Subaqueous Depots (after DEPOTEC, 2002) curriculum in natural environmental science, 2005

Sediment Capping Techniques: Active Barrier System Combination of Physical and chemical Stabilisation Layers on Sediment (Jacobs, 2003) curriculum in natural environmental science, 2005

Active Barrier System – Demonstration Project Hitzacker (I) Subaqueous Depot and Active Barrier System (Design: Josef Möbius, Hamburg) curriculum in natural environmental science, 2005

gas emission monitoring tensiometer piezometer test field/ enclosures climatic monitoring sheet piling deposit bridge relocated sediment meanwater level Active Barrier System – Demonstration Project Hitzacker (II) Subaqueous Depot and Active Barrier System (Testing Devices: Jacobs, 2003) curriculum in natural environmental science, 2005