A direct observation technique for the study of microorganisms in sediment samples

A technique is described for the incubation of sediment samples under controlled conditions and the examination of the sediment by direct microscopy after percolation with a fluorescent stain — the ammonium salt of 8-anilino-1-naphthalenesulfonic acid. The incubation chamber employed enables the sediment sample to be treated by percolation with nutrients or with toxic chemicals. The response of the sediment microorganisms to these amendments can be analyzed using pattern determination statistics or direct counts at intervals during incubation.     

Impact of Nitrate Addition on Phosphorus Availability in Sediment and Water Column and on Plankton Biomass-Experimental Field Study in the Shallow Brackish Schlei Fjord (Western Baltic, Germany)

The Schlei is a hypertrophic brackish fjord of the Baltic. In order to assess the optimal method for restorative sediment treatment, an in-situ-experiment was carried out to oxidize the uppermost sediment strata by direct nitrate injection. An area of 3,5 ha, covered with sapropelic sediment, was treated with 50 t of commercial calcium-salpetre. Half of this area was treated once with a dose of 140 g NO3-N m-2, whereas the other half was treated twice receiving a dose of 280 g NO3-N m-2. Two enclosures were installed on these treated areas. The reaction in the interstitial water of the sediment (nitrate, phosphate, sulphate, iron) and in the water bulk (tot-N, tot-P) are documented and compared with an untreated reference area. Moreover, the impact of the sediment treatment on the phyto- and zooplankton biomass is discussed.     

Run-off and sediment yield in relation to differential gully-plugging schemes in micro-catchments of Shiwaliks in the lower Himalayas

Gully-management strategies adopted in the Shiwalik range of hills in the lower Himalayas of India, which involve treatment of only higher order gullies, have not been successful. A study was conducted in the four selected micro-catchments in the region to monitor run-off and sediment yield variations in relation to differential gully-plugging schemes. One of the study catchments (catchment III) with highest run-off and sediment yield was selected for an alternative scheme of gully management. In this, all the first-order and 25–30% of the second-order gullies were plugged with locally available stones, and native grass vegetation wasplanted on the upstream side. Other catchments (catchments I, II and IV) were treated as per the the conventional method of gully plugging involving the installation of loose stone check dams in the highest order gullies. The highest run-off coefficient (15.5%) for the period 2000–2006 was registered in catchment III. However, this decreased to 12.8% during 2007, when the catchment was treated using an alternative gully-management scheme. The sediment yield from catchment III decreased by 20% in 2007 from 15.2 t ha^?1 during 2000–2006. The results indicate that to control gully erosion, lower order gullies should be treated as a priority.     

太湖湖积物及黄海潮间海积物中氮的反硝化及硝态氮还原成铵的研究

Denitrification and nitrate reduction to ammonium in Taihu Lake and Yellow Sea inter-tidal marine sediments were studied.The sediment samples were made slurry containing 150g dry matter per liter.Various of glucose-C to nitrate-N.Acetylene inhibition technique was applied to measure denitrification in the slurres,All samples were incubated anaerobically under argon atmosphere,Data showed that Taihu Lake sediment produced more N2O than marine sediment,Denitrification potential was higher in Taihu Lake sediment than in marine one,Glucose added increase denitrification activity but not the denitrification potential of the sediments.Dissimilatory nitrate reduction to ammonium seemed to occur in marine sediment,but not in freshwater one.When the marine sediment was treated with 25mmol L^-1 glucose,its denitrification potentail,as indicated by maximum N2O production by acetylene blockage,was lower than that treated with no or 2.5mmol L^-1 glucose.Acetylene was suspected to have inhibitory effect on dissimilatory nitrate reduction to ammonium.     

皇甫川流域综合治理对河道冲淤变化影响的研究

皇甫川系黄河的一条多泥沙河流,至1997年底流域治理度达28.2％。水土保持综合治理对削减中小洪水水流动量的作用明显,河流中的中粗粒径泥沙所占比重变小,细粒径泥沙所占比重增大。减水幅度与减沙幅度不同,河道断面未发生大的调整。水土保持蓄水拦沙和减轻黄河泥沙淤积的作用,为深化流域综合治理提供了理论依据。     

Effect of copper on nitrous oxide reduction in freshwater sediment

The effect of Cu(II) sulfate on N20 reduction was studied in anaerobically incubated freshwater sediment at 15 °C. At Cu concentrations from 100 to 5000 μg g^?1, a concentration-dependent decrease in sediment pH was observed in conjunction with a decrease in N₂0 reduction in Cu²⁺ treated sediment in flask-microcosms analyzed immediately after metal addition. However, if flask-microcosms were amended with Cu²⁺ and then pre-incubated to allow the sediment pH to naturally return to its original pH (7.1), an inhibitory effect was only produced at 5000 μg Cu g^?1 sediment. Copper retention studies showed that up to 96.4% of the added Cu²⁺ (2500 μgg^?1) was retained by sediment.     

Laboratory-Scale Investigation of Ferrihydrite-Modified Diatomite as a Phosphorus Co-precipitant

The potential of ferrihydrite-modified diatomite as a phosphorus co-precipitant was investigated at a laboratory scale. Ferrihydrite-modified diatomite was demonstrated to effectively remove phosphorus from lake water as well as strongly bind phosphorus in sediment under anoxic conditions. Phosphorus removal from the lake water proceeded primarily through phosphorus adsorption onto ferrihydrite-modified diatomite and further phosphorus consumption by stimulated diatom growth. A total phosphorus removal efficiency of 85% was achieved when lake water was dosed with 250 mg/L ferrihydrite-modified diatomite; the residual total phosphorus concentration was 17.0 µg/L, which falls within the range for oligotrophic phosphorus levels. During a 30-day anoxic incubation period, total phosphorus concentrations in lake water treated with 400, 500, or 600 mg/L of ferrihydrite-modified diatomite slightly decreased and maximum total phosphorus concentrations remained below 15 µg/L. Addition of ferrihydrite-modified diatomite resulted in a marked increase in the iron-bound phosphorus fraction, a pronounced decrease in labile phosphorus and organic-bound phosphorus fractions, and stable aluminum-bound phosphorus, calcium-bound phosphorus, and residual phosphorus fractions in the anoxic sediments. Comparable iron-bound phosphorus concentration in the sediment treated by 400 mg/L of ferrihydrite-modified diatomite relative to that of the sediment treated by the combination of 400 mg/L of ferrihydrite-modified diatomite and alum solution at the concentration less than 532 mg/L indicated that ferrihydrite-modified diatomite exhibited a stable phosphorus-binding capacity when dosed at a similar amount. Ferrihydrite-modified diatomite had the potential to be used as an effective phosphorus co-precipitant.     

Sediment Retention by Alternative Filtration Media Configurations in Stormwater Treatment

Urban stormwater can be treated by infiltration at the source using systems like permeable paving. A critical component of such a system is the filtration media. Laboratory experiments were conducted using columns and boxes to evaluate the sediment retention efficiencies of different filtration media—crushed Greywacke, Greywacke mixed with 10% sand, and layered Greywacke and sand-Greywacke mix. Sediments of 0.001–6 mm were applied at concentrations of 460–4,200 mg/l along with water at flow rates of 100–900 ml/min. All columns showed between 96 and 91% sediment retention efficiency for single dry sediment applications, with lowered sediment retentions at higher flow rates. Decreasing the sediment loading, applying particles of <38 μm size, and suspending the particles in inflow as opposed to directly applying sediments to the column surface gave lower sediment retention efficiencies of 55 to 89%. Sediment retention primarily occurred in the top 20 mm of all columns and the 50th percentile value of retained sediments was 100–300 μm. The box tests showed little effect of flow and sediment loading on particle retention, with the tests showing an average retention of 93%. Similar to the column tests, the box tests showed lower sediment retention (84 to 88%) for <38 μm sediments and greater retention (approximately 95%) for larger sediments.     

Particle Size Selectivity Considerations in Suspended Sediment Budget Investigations

The delivery of suspended sediment front drainage basins has frequently been quantified in mass terms by use of the sediment budget approach, which identifies sources. Storage and output of mobilised sediment. An attempt is presented here to define the main components of a generalised suspended sediment budget for a drainage basin in Devon, U.K. in teens of particle size characteristics and grain size selectivity, rather than total amounts of sediment. Samples of sediment mobilised from the hillslopes, fluvial suspended sediment and suspended sediment deposited on the river bed were all collected for particle size characterisation. These samples were then treated to remove organic matter and their chemically dispersed (absolute) particle size composition was measured using a Coulter LS130 laser granulometer. Where possible, measurements of the naturalin-situ particle size distribution (effective particle size) were also undertaken. Samples were collected at different times of the year so that temporal variation of hydromcteorolgical and ground conditions was represented. Comparison of the results for the different components of the delivery process shows that significant particle size selectivity occurs in the mobilisation and transfer of sediment from the hillslopes to the basin outlet. This reflects the particle size selectivity of detachment, transport and deposition processes, which is in turn influenced by the aggregation or flocculation (effective particle size) of the sediment.     

玉米茎秆汁液对黄土坡面产沙速率的影响及原因分析

利用人工模拟降雨试验研究了玉米茎秆汁液对黄土坡面产沙速率的影响及其原因。试验设计了4种不同的土样处理方式（control、添加25%浓度的汁液、添加50%浓度的汁液、添加25%浓度汁液经过一个冬季的冻融降解）在4种不同雨强（25,50,75,100 mm/h）下对产沙速率的影响,分析了4种不同处理后土样的土壤团聚体、有机质跟产沙速率的关系。结果表明:（1）添加玉米茎秆汁液对产沙速率是有明显的抑制作用的,玉米茎秆汁液通过增加土壤中 > 0.25 mm的团聚体和有机质实现减沙作用的。（2）4种处理后的土样中 > 5 mm的土壤团聚体和有机质是显著线性相关的,通过了0.01的显著性水平。在各种试验雨强（25,50,75,100 mm/h）下的产沙速率与 > 0.25 mm的土壤团聚体、有机质都具有显著线性负相关关系,通过了0.01的显著性检验。     

泥沙来源“指纹”示踪技术研究综述

泥沙来源"指纹"示踪技术是综合研究流域土壤侵蚀和泥沙输移的新方法。泥沙来源"指纹"示踪技术基于流域侵蚀产沙过程划分潜在物源类型,根据物源特性筛选具有诊断能力的"指纹"性质,通过定量转换模型建立流域出口泥沙与内部潜在物源间的"指纹"联系,定量描述各潜在物源对流域出口产沙的相对贡献;结合悬移质或沉积泥沙通量监测,定量分析各潜在物源对流域产沙的绝对贡献量及流域侵蚀产沙时、空变化特征。通过综述泥沙来源"指纹"示踪技术的理论基础及实施框架,流域尺度潜在物源类型,泥沙"指纹"因子类别、分布特点及诊断能力,泥沙来源复合"指纹"示踪技术的研究进展,指出泥沙来源"指纹"示踪技术的局限性,并对泥沙来源"指纹"示踪技术进行展望。     

Towards an Optimized Protocol for Measuring Global Dehydrogenase Activity in Storm-Water Sediments (10 pp)

Background, Aim and Scope   Microorganisms play an important role in the biogeochemical cycles of soils and sediments; hence the microbiological quality of these environments can be evaluated by measuring microorganism population densities, diversity and enzyme activity. For example, dehydrogenase activity is known to be sensitive to pollutants, such as heavy metals, and to correlate with the carbon cycle. This article presents an optimized protocol for measuring dehydrogenase in a range of different sediments and, more precisely, in urban storm-water sediments. The influence of blank preparation, ratio substrate/sediment and time of formazan extraction was studied on sediments coming from urban sewage works, or lakes and rivers. Materials and Methods   After a microbial and chemical characterization of the sediments studied, the initial protocol of dehydrogenanse measurement consited in incubating 2 g of dry sediment with 2 μmol of INT (the substrate) at 37°C for 24 hrs. It was carried out on three different urban storm-water sediments. Once an optimum dehydrogenase activity was obtained, the new protocol was tested on six other sediment materials. Results   The results for all the sterilized samples were significantly different to those obtained for the corresponding, non-sterilized sample, with the exception of the St Vallier sediment, which was treated with formaldehyde or the maximum dose of gamma radiation. Sediments that are rich in organic matter must be treated with high concentrations of INT in order to reach, or approach, substrate excess, especially if it is intended to compare formazan measurements. In order to more easily achieve excess substrate, we investigated the possibility of reducing the quantity of solid matter used for the tests. For the two samples tested, and especially for the road basin sample, tests carried out using a ratio of sediment mass (in g) to INT quantity (in μmol) of 0.05 (0.5 g of sediment/10 μmol INT) produced values of 2000-2200 μg of formazan/g of sediment/24 hrs. Activities are much lower (between 1.5 and 3 times lower) when the ratio is equal to 0.2. Sonication should increase formazan extraction as it separates aggregates, thereby improving the contact between the acetone and the sediment. Sonication has an effect on the extraction of formazan. For sample EC2, 30% more formazan was extracted with sonication than without. Discussion   Sterilization by formaldehyde and by autoclaving demonstrated very different levels of activity. Autoclaving is the least satisfactory sterilization method, as the modifications it causes, especially to the sediment texture, are too great (Trevors 1996). The main advantage of sterilization by irradiation is the minimal disturbance of the sediment structure (Trevors 1996, McNamara et al. 2003). The quickest and most economic sterilization method is the use of formaldehyde. Therefore, blanks sterilized using formaldehyde were used in the tests of the different methods. Organic matter absorbs INT salts, so they are no longer bioavailable for the microorganisms. Sediments that are rich in organic matter must be treated with high concentrations of INT in order to reach, or approach substrate excess, especially if it is intended to compare formazan measurements. Based on our results, the results reported in the literature and practical considerations, such as the solubility of INT and the toxicity of INT with respect to bacteria (Hatzinger et al. 2003), we decided to use a quantity of INT equivalent to 10 μmol (i.e. 2.5 mM in a final concentration in the test) for our subsequent experiments, even though we realized this would not produce saturation conditions for the highly organic sediments. In order to more easily achieve excess substrate, we investigated the possibility of reducing the quantity of solid matter used for the tests. The literature shows that previous work has often been carried out using 1 g samples of dry soil or dry sediment (Merlin et al. 1995, Taylor et al. 2002, Benitez et al. 2004, Plaza et al. 2004). Here, we find a direct relation between the amount of sample and the reduction of the substrate. To ensure that samples remained representative, it was decided not to test samples of less than 0.5g dry weight. Acetone was chosen as the extractant, as it has been used by many other workers (Brohon 1998, Engelen et al. 1998). Sonication has an effect on the extraction of formazan. Kruskal and Wallis tests, at p=0.05, show that the increase of INT extraction is significant for EC2 at 10 minutes, but not for EC1. EC2 is much coarser (around 75% sand and 25% silt) than EC1 (40% sand and 60% silt) (data not shown). This difference in grain size distribution may be one explanation for the different behavior of the two matrices when subjected to sonication .This pretreatment is known to destroy aggregates. Therefore, in order to measure the maximum activity, the acetone extraction time, with or without ultrasound, must be chosen to suit the matrices being studied. So, depending on the characteristics of the sediment (mostly the grain size distribution), it may be useful to use ultrasound in order to achieve a good level of formazan extraction. The method to be used must be determined for each sediments. Conclusions   When tested on different types of sediment (river, urban sewage, etc.) the optimized protocol (0.5 g sediment and 10 μmol of INT) gave higher activity measurements than the initial protocol and appears to provide a useful test method for comparative studies or for monitoring sediment quality. The organic matter content appeared to be one the most important parameter controlling the measurement and playing an important part on the different contact and extraction steps of the experiment. The best method for preparing blanks is sterilization using gamma radiation, as this has the lowest impact on sediment structure. However, if cost and time considerations render this method impracticable, samples can be sterilized using formaldehyde. Recommendations and Perspective  : The final protocol can be used to monitor the spatial (in terms of the different vertical and horizontal zones at the surface) and temporal (monitoring changes in activity over time using surface samples taken after different rain events) evolution of this activity within sediment samples from rainwater infiltration basins.     

Effect of Steel Slag to Improve Soil Quality of Tsunami-Impacted Land while Reducing the Risk of Heavy Metal Bioaccumulation

After the tsunami caused by the Great East Japan Earthquake, marine sediment was taken from the sea bottom and deposited over local agricultural fields. The marine sediment already contained an unknown amount of heavy metals, due to anthropogenic activities prior to the tsunami, which might affect plants, animals, and humans. Furthermore, soil salinity in tsunami-inundated land greatly increased. Three different amounts of steel slag were employed as pretreatment agent in order to improve agricultural soil quality. The soil samples treated with 2% of steel slag present a remarkable increase of A. thaliana biomass production with low BCF and TF values for most of the heavy metals. It was concluded that steel slag pretreatment used in the tsunami-inundated agricultural lands produced a noteworthy improvement in soil quality which lead to a positive stimulative effect on plant growth, and the slag addition treatment proved to be a promising treatment that might be used for phytostabilization of slightly contaminated soils.     

黄河中游水利水保措施减沙效益分析中几个值得注意的问题

河流输沙量的变化受流域降水和下垫面影响很大。采用水文法分析水利水保措施减沙效益时应注意如下问题:降雨量是最重要的基础资料,要认真分析工程实施前后雨量站的分布、代表性及前后期降雨量的可比性;暴雨对产沙的影响很大,暴雨强度是决定产沙量多少的重要参数,选用有效降雨量、有效降雨强度能较好地反映暴雨产沙作用;用径流量预报产沙量要区别地下、地表径流的不同影响;要考虑不同地貌类型区对产沙量的影响。     

Is risk-based,sustainable sediment management consistent with European policy?

Background, aims and scope  One issue that remains particularly problematic for integrated and sustainable sediment management is that sediment plays differing roles in various sectoral, regulatory and statutory objectives. This means that across Europe, the level of consideration afforded to sediment management has thus far been primarily left to the discretion of individual countries and agencies. One of the consequences of the complex way in which sediments are regulated in Europe, and a possible over-reliance on the precautionary principle, is that there appears to be less regulatory acceptance of risk-based (rather than mass-based or chemical threshold-based) sediment remedial decisions, and thus resistance to some of the risk-based and in situ remedial technologies currently favoured in North America; “presumptive remedies” are being pushed by a number of agencies, and in-place and risk-based management are meeting great resistance. This summary discusses some of the current and emerging European regulations and strategies and their implications for risk-based sediment management. Conclusions, recommendations and perspectives  There are numerous examples of ex situ remedial strategies in Europe, where sediments are either treated or contained (and increasingly, considered for beneficial use), but very few examples of in situ management. However, the risk-based evaluation of ALL remedial options is entirely consistent with European environmental policy. In fact, in some cases, presumptive removal of sediments can result in greater risks to human health and the environment than management in place, and thus a failure to meet Europe’s ambitious environmental objectives. Decisions that only address a single, sectoral regulatory driver (such as a desire to remove contaminants from a waterbody) may result in a net detriment to the environment. The European Commission has stated that decisions and policies should be continuously evaluated in the light of emerging science and experience, and, where possible, rigorous science-based risk evaluation should take the place of the application of conservative safety factors. Whilst not specifically addressing sediment management, various European Directives and initiatives set out principles for the selection of land-based remedial options that are consistent with a number of international consensus guidance documents on the site-specific, risk-based selection of contaminated sediment remedial options. Although there are numerous technical differences, the fundamental risk- and cost-based principles being applied to land management should be transferable to sediment management decision frameworks. However, whilst the use of risk-based decision criteria is now well-established (either in principle or in practice) in Europe for soil remedial decisions, these principles have not yet been translated to generally applied decision frameworks or guidance for contaminated sediment management in Europe. There is no reason, however, why they should not be.     

Nutrient Accumulation in Typha latifolia L. and Sediment of a Representative Integrated Constructed Wetland

This paper investigates the role of plants and sediment in removing nutrients from wastewater being treated in a representative integrated constructed wetland (ICW). It discusses the role of plants and sediment in removing nutrients from an ICW treating agricultural wastewater for more than 7 years. More nitrogen and phosphorus were stored in wetland soils and sediments than in plants. The first cell had the highest depth of sediment accumulation (45 cm). Over the 7-year operation period, the accretion rate was approximately 6.4 cm/year. With respect to maintenance, desludging of the first wetland cell of the ICW system appears to be necessary in 2011. An average of 10,000 m³ per year of wastewater entered the ICW. Approximately 74% (780 kg) of the phosphorus and 52% (5,175 kg) of the nitrogen that entered the wetland system was stored in the wetland soils and sediments. Plants stored a small fraction of nutrients compared to soils (<1% for both nitrogen and phosphorus). This study demonstrates that soils within a mature wetland system are an important and sustainable nutrient storage component.     

Yellow River Sediment as a Soil Amendment for Amelioration of Saline Land in the Yellow River Delta

Soil salinization and sedimentation in the Yellow River Delta pose significant environmental concerns in China. This study demonstrated for the first time that the Yellow River sediment can be used as a soil amendment to remediate the salt‐affected soil. Four treatments including the control (CK), Yellow River sediment application at 70 Mg ha⁻¹ (S70) and 140 Mg ha⁻¹ (S140), and crop residue application at 3 Mg ha⁻¹ (P3) were replicated in two blocks in the field. Cotton, one of the most common crops in the Yellow River Delta, was planted. Soil physical properties and electrical conductivity (EC) were measured. The results indicated that mixing the Yellow River sediment, a poorly graded sand, with the clayed saline soil improved soil texture, macroporosity, and saturated hydraulic conductivity. Mean EC of treated soils was significantly lower than for the control. Improved cotton emergence and stand establishment were observed along with a significant treatment effect on cotton yield. The effects of S140 and P3 on soil macroporosity, hydraulic conductivity, soil EC, and cotton growth were comparable. This study concluded that applying Yellow River sediment in the saline land is a technically feasible and environmentally sustainable approach for saline soil remediation in the Yellow River Delta. Copyright © 2014 John Wiley & Sons, Ltd.     

The significance of various sediment magnetic mineral fractions for tracing sediment sources in Killimicat Creek

The mineral magnetic properties of sediment are increasingly being used to determine the sources of sediment, and associated nutrients and contaminants in drainage basins. This study was undertaken to measure the relative contributions of the magnetic mineral components in sediment (i.e., components associated with surface bound Fe, the heavy mineral fraction, and as inclusions in particles) to determine the extent to which they represent the bulk of the sediment. Deposited channel sediment samples from the tributaries and downstream reach at the first major confluence in the headwaters of Killimicat Creek, New South Wales, were sieved to separate 6 particle size fractions, and the mineral magnetic properties measured to determine the relative contribution of sediment from the smaller tributary basin. The finest sand component (63–125 μm) was then separated into light and heavy mineral fractions, and magnetic measurements made on each fraction. Magnetic parameter data from the 63–125 μm fraction, measured before density separation, show a dominance of sediment (70±12%) derived from the smaller tributary basin. Measurements of the light sediment fraction give a similar result (73±13%). The proportion of the heavy mineral fraction delivered from the smaller tributary is 78±38%. The light mineral fraction of all of the samples were treated with HCl to remove surface bound Fe, and subsequent magnetic measurements show that 41–94% of the mass specific magnetic susceptibility is attributable to magnetic minerals associated with surface bound Fe. The heavy mineral component, while <4% by weight of the 63–125 μm fraction, contributes 5–40% of the total magnetic susceptibility. The results show that most of the magnetic mineral component (>60%) is associated with sediment particles, rather than the discrete heavy mineral component.     

夹沙螺旋管流能耗的试验研究

在水平圆管中设置导叶式起旋器,使管内夹沙水流形成了强制螺旋流,螺旋流可以分解为强制涡流与轴向平直流,前者可起“抬托”泥沙的作用,后者则同普通管道输送固粒一样起输移的作用,这样使本来以推移质形式运动的泥沙较为容易地转变成悬移质。该文应用动量和动量矩定律,对圆管内强制螺旋流的清水与夹沙两种情况进行了理论分析和试验研究,得到的结论是:螺旋管流的能坡可以用达西公式来表达;其夹沙能力远高于同能坡下的平直流情况;在非饱和状态下,附加“旋浮”沙的能坡正比于含沙量     

Quality Criteria for Re-Use of Organotin-Containing Sediments on Land (7 pp)

Background, Aim and Scope   The use of organotin compounds as antifouling agents on ships is prohibited at EU level since 1 July 2003. Because of its persistence, the presence of organotin compounds in harbour sediment will however remain a problem for years. Dumping of dredged sediment in sea is subject to very strict quality criteria, stimulating the exploration of re-use alternatives, such as re-use on land. Within the TBT Clean project (EU LIFE Project 02/ENV/B/341) an assessment framework for re-use of organotin containing treated sediment on land as secondary granular building material was developed. Three scenarios were considered: free re-use on land, re-use above groundwater level with cover layer, and re-use under groundwater level (the latter two scenarios are referred to as restricted re-use). Receptors considered were humans, ecosystem and groundwater. Generic upper concentration limits and sediment leaching limits were calculated. Materials and Methods: Upper concentration limits were calculated with the Vlier-Humaan model. This model allows to calculate soil remediation values according to the Flemish legal framework. The focus of the methodology is the protection of human health, although a check for ecotoxicity was included in the project. The soil remediation value for residential land-use was selected within the scenario for free re-use; for restricted re-use (no direct contact possible), the soil remediation value for industrial land-use was selected. Leaching values were calculated with an analytical soil and groundwater transport model. The reference scenario behind the leaching criteria of the European Landfill Directive was modified to fit the project objectives. Default values for application height and length were used. The point-of-compliance was situated at 20 m distance in the groundwater. Physicochemical properties were taken from literature; sorption characteristics were taken from literature and were measured on 6 treated sediment samples during the project. Plant-uptake values were taken from the literature. Toxicological criteria were taken from EFSA. Results: The assessment framework provided an upper limit (SedUL) and an leaching value (SedLV) for each scenario, expressed as mg/kg dm in the sediment. Criteria were calculated for tributyltin (TBT) and dibutyltin (DBT); too few data were available for monobutyltin (MBT). The SedUL equalled 0.51 mg TBT/kg dm and 0.07 mg DBT/kg dm for free re-use and 195 mg TBT/kg dm and 205 mg DBT/kg dm for restricted re-use (two scenarios). For free re-use the SedLV was only limiting for TBT at Kd of < 2000 l/kg in the sediment. Under re-use above groundwater level with coverage SedLV values ranged from 6.9 – 29 mg TBT/kg dm and from 12 – 33.3 mg DBT/kg dm (Kd ranging from 100 – 10000 l/kg); under re-use below groundwater level SedLV values ranged from 0.007 – 0.77 mg TBT or DBT/kg dm (Kd ranging from 100 – 10000 l/kg). Discussion: Results are subject to large uncertainties because of variation in input data; the model output is sensitive to variation in plant uptake (SedUL for free re-use), Koc or Kd (SedUL for restricted re-use, SedLV for re-use with coverage), Henry's law coefficient (SedUL for restricted re-use); all these parameters show orders of magnitude variation. Conclusions: A feasible and consistent framework for evaluation of the re-use of treated organotin containing sediment was developed. However, the resulting quality criteria are still subject to large uncertainties, due to uncertainties in input data. Recommendations and Perspectives: High-quality data on plant uptake and soil sorption of organotin compounds, the influence of soil properties on these processes, and long-term terrestrial toxicity data are needed to refine the calculations. The quality criteria should be reviewed when these data become available.