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Anthropogenic activity leads to changes in sediment dynamics, creating imbalances in sediment distributions across the landscape. These imbalances can be variable within a littoral system, with adjacent areas experiencing sediment starvation and excess sediment. Historically, sediments were viewed as an inconvenient biproduct destined for disposal; however, beneficial use of dredge material (BUDM) is a practice that has grown as a preferred methodology for utilizing sediment as a resource to help alleviate the sediment imbalances within a system. BUDM enables organizations to adopt a more innovative and sustainable sediment management approach that also provides ecological, economic, and social co-benefits. Although location data are available on BUDM sites, especially in the US, there is limited understanding on how these sites evolve within the larger landscape, which is necessary for quantifying the co-benefits. To move towards BUDM more broadly, new tools need to be developed to allow researchers and managers to understand the effects and benefits of this practice. The National Exposed Sediment Search and Inventory (NESSI) was built to show the capability of using machine learning techniques to identify dredged sediments. A combination of satellite imagery data obtained and processed using Google Earth Engine and machine learning algorithms were applied at known dredged material placement sites to develop a time series of dredged material placement events and subsequent site recovery. These disturbance-to-recovery time series are then used in a landscape analysis application to better understand site evolution within the context of the surrounding areas. [ABSTRACT FROM AUTHOR]

Purpose: Sediments from marine areas contain salt, limiting beneficial use possibilities. This study investigates the impact of rinsing with fresh water on ion concentration and organic matter (OM) content in marine sediments, and how salinity hinders water release under induction. Methods: In a lab simulation, marine sediment was mixed with fresh water (1:6 volume ratio) for 5 min at 285 rpm using a HOBART planet N-50 Mixer. An adapted Thermogravimetric Analysis (TGA) procedure determined the OM content and the temperature at which all water was released. Results: Mixing sediment with fresh water reduced ion concentrations. Monovalent ions like sodium and chloride were released immediately, while higher valence ions like sulfate and phosphate were released gradually. Rinsing with fresh water also reduced OM content. A second mix with the salty supernatant water did not further reduce salinity or OM. Conclusion: Determining OM content in salty sediments requires continuous mass loss monitoring to identify the temperature at which all water is removed. For agricultural reuse, maintaining nutrient levels and OM while reducing salt content to prevent groundwater salinization is crucial. Supernatant water should be removed promptly after rinsing to halt nutrient removal. The results of this study contribute to beneficial reuse of dredged sediment. [ABSTRACT FROM AUTHOR]

Purpose: The EU Water Framework Directive (European Union Off J Eur Comm 2000) and EU Waste Framework Directive (European Union Off J Euro Union 2008) impacted the Beneficial Use (BU) of sediments in Europe. INTERREG has supported initiatives to change the perception that sediments are a waste. In this paper we provide an overview of tools, pilot sites and measuring techniques developed and used for the BU of sediments within seven European Union INTERREG projects. We illustrate the lessons learned regarding barriers and enablers for BU of sediments. Materials and methods: BU of sediments is a combination of factors. The following aspects are considered. The sediment must be suitable for use and be in engineering compliance. The sediment must also need to meet the end of waste criteria, as well as to be in environmental compliance. To check in the field if engineering and environmental compliance is feasible, on-site analyses and decision support tools are needed. When BU use is possible, there must be a benefit, either in an added socio-economic value or in ecosystem services. To define benefits the impact of Business as Usual (BAU) should also be expressed. Stakeholder perception and spatial restraints determine areas for BU of sediments with spatial consensus. Results and discussion: The pilots and case studies described in this paper are examples of different applications of BU of sediments in northwest Europe. The tools, equipment, pilot tests and on-site monitoring techniques developed by the identified INTERREG projects are useful as BU enablers, for both citizens (an enabler is what is in it for me versus a barrier like residents opposing to proposed developments in their local area or the Not In My Back Yard (NIMBY) principle), and for regulators (what are the risks versus benefits as compared to BAU). Conclusions: The main barriers for beneficial use of sediments are the social acceptance when sediments are used on land (often seen as waste disposal) and the extra direct cost versus the cost for disposal, while indirect benefits such as the potential for nature development, the impact on Gross Domestic Product (GDP) or more locally on the extra jobs created, are generally not considered. Also, the impact of BAU is often not explicitly considered. [ABSTRACT FROM AUTHOR]

Tidal marshes provide numerous ecosystem services, but are threatened by recent increases in global sea level rise (SLR). Marsh restoration and creation are important strategies for mitigating marsh loss, restoring ecosystem services, increasing coastal community resilience, and providing much needed habitat for threatened species. Dredged material resulting from navigation channel maintenance can provide a substrate for these restoration projects. Few studies, however, have addressed the sustainability of these marshes. The Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island, where fine-grained, nutrient-rich dredged material from upper Chesapeake Bay is being used to create > 302 ha of tidal marshes, provides a case study. The low supply of inorganic sediment is counteracted by abundant nutrients, stimulating high rates of organic matter production and elevation change. Using > 10 years of data from 39 surface elevation tables, we found that the mean low marsh rate of elevation change (7.7 ± 3.21 mm year−1) was double the mean high marsh rate (3.6 ± 0.47 mm year−1) and exceeded the natural reference marsh (3.0 ± 2.28 mm year−1) and relative SLR (5.7 mm year−1). By stimulating organic matter production, the high nutrient substrate appears to offset the low inorganic sediment inputs in mid-Chesapeake Bay. Spatial variability was correlated with initial elevation, but was also influenced by local factors that may affect sediment redistribution within the marshes. [ABSTRACT FROM AUTHOR]

Due to observed impacts of sea level rise, many sediment management strategies in coastal settings are seeking ways to beneficially use locally dredged sediment in restoration, nourishment, and construction projects. The placement of sediment in shallow, near-marsh areas is a promising application of dredged material to both increase accretion and provide protection to marshes and intertidal flats in back bay areas. However, dredged material in these areas often include fine-grained (<63 mm) sediments (FGS), that frequently raise questions concerning dispersion, stability, and environmental impact of the placement project. In 2020, approximately 30,500 m³ of FGS from the New Jersey Intracoastal Waterway (NJIWW) was placed along the southern edge of Gull Island, New Jersey to evaluate the feasibility of using FGS for beneficial use projects in near marsh environments. Gull Island was experiencing extensive marsh edge erosion through margin collapse. The placement was unconfined and resulted in the formation of two intertidal muddy berm-like features up to 0.7 m thick along more than 500 m of marsh. Bathymetric surveys showed that approximately 60-70% of the berm volume remained 36 months after placement, however maximum berm thickness reduced to ~0.5 m. Field monitoring performed during construction found that turbidity plumes were localized to within 100 m of the placement site and sediment cores collected in June 2022 did not show systemic winnowing from the berm surface. Laboratory and field observations indicated that the berm material was cohesive in nature and produced large aggregates upon erosion, limiting the dispersal of FGS. Observations of current velocities and waves in the area indicate a low energy system such that the cohesive berm was largely resistant to erosion and that reduction in berm volume was largely due to consolidation and compaction. This suggests that shallow water features can be constructed with FGS in similar low energy environments with limited dispersal during and following construction, while being robust enough to help stabilize the marsh edge and improve marsh survivability against sea level rise. [ABSTRACT FROM AUTHOR]

Due to observed impacts of sea level rise, many sediment management strategies in coastal settings are seeking ways to beneficially use locally dredged sediment in restoration, nourishment, and construction projects. The placement of sediment in shallow, near-marsh areas is a promising application of dredged material to both increase accretion and provide protection to marshes and intertidal flats in back bay areas. However, dredged material in these areas often include fine-grained (

Türkiye’de kentsel dönüşüm projeleri nedeniyle oluşan agrega ihtiyacı, özellikle büyük şehirlerdeki sınırlı sayıdaki ocak sahalarında alan ve kaynak kullanımının optimizasyonunu gerektirmektedir. Bu çalışmada, İstanbul'da bir taş ocağından kırmataş üretimi sonrası açığa çıkan artık malzemenin yol kesimlerinde kullanılabilirliği değerlendirilmiştir. Kaba dane oranı KDO %75-51 arasında olan malzeme siltli kum (SM) sınıfındadır. Standart enerji SE (600 kN-m/m3) ve modifiye edilmiş ME enerjisinde (2700 kN-m/m3) belirlenen optimum su içeriği (wopt) değerleri, plastik olmayan artık numunelerindeki sınırlı kil fraksiyonu nedeniyle sırasıyla %11 ve %8 ile sınırlı kaldığı gözlenmiştir. Buna göre KDO ile doğru orantılı olarak artan ıslatılmış CBR değerleri SE'de %9-16, ME'de %45-67 arasında değişmektedir. D10 efektif çapı ile doğru orantılı olarak artan geçirgenlik değerleri SE’de 2,2 x 10-6 - 5,0 x 10-6 m/s ve ME'de 1,2 x 10-6 - 3,7 x 10-6 m/s'dir. Direk kesme kutusu testlerinde kohezyon (c) değerleri ihmal edilebilir düzeyde olduğu belirlenmiş ve iç sürtünme açısı (ϕ) sıkıştırma enerjisiyle orantılı olarak artmıştır. KDO ile doğru orantılı olarak artan ϕ değeri SE'de 38-40°, ME'de 43-47° arasında değişmektedir. Sonuç olarak, incelenen ocak artığının ince dane oranının sınırlandırılmasının yol dolgu ve temel altı uygulamalarında kullanılabilirliğini sağlayacağı öngörülmektedir.

Despite rapidly expanding interest in the use of natural coastal habitats for their ability to protect against erosion and flooding, implementation of coastal natural infrastructure (NI) projects has been limited to date. Uncertainty over how the benefits of NI will change over time as they mature and adapt to changing environmental drivers, and a lack of well-documented demonstrations of NI, are often cited as roadblocks to their widespread acceptance. Here, we begin to fill that knowledge gap by describing implementation and early (3 years post-implementation) monitoring results of an NI project at Swan Island, MD. Swan is an uninhabited marsh island in mid-Chesapeake Bay, United States whose position renders it a natural wave break for the downwind town of Ewell, MD. Prior to project implementation, Swan had experienced significant losses in areal extent due to subsidence and erosion. To reverse this trend, the island was amended with dredged sediments in the winter of 2018–2019. The overarching goal was to preserve the Island’s ability to serve as a wave break and make it more resilient to future sea level rise by increasing the elevation of the vegetated platform, while also increasing the diversity of habitats present. A monitoring program was implemented immediately after sediment placement to document changes in the island footprint and topography over time and to evaluate the extent to which project goals are met. Data from the initial three years of this effort (2019 through 2022) indicate an island that is still actively evolving, and point to the need for rapid establishment of vegetative communities to ensure success of coastal NI.

[Display omitted] • Waste-derived soil amendments used to mitigate COPCs from MSWI ash leachate. • Experimental K d values for soil/amendment blends used in fate/transport model. • Data on sorption of COPCs from ash leachate using biochars presented. • Amendments may increase ash reuse potential from environmental risk viewpoint. This study explores modifying a sandy soil with a low solid to liquid partitioning coefficient (K d) by adding amendments including iron-rich industrial slag byproducts and biochars, which contain sorption sites for trace metals present in MSWI ash leachate (notably Sb, cited as a concern for reuse applications). K d values for Sb were determined for the sandy soil to be as low as 1.6 ± 0.1 L/kg. With amendments, K d values varied from 1.4 ± 0.2 L/kg for combined ash leachate exposed to a blend of sandy soil and 20% iron slag, to 990 L/kg for combined ash leachate exposed to a blend of sandy soil and 20% magnetic solids. A blend of 20% magnetic solids showed orders of magnitude increase beyond 100% sandy soil. The biochars showed limited capacity to reduce leached Sb in the ash-derived leachate, which is likely due to negative surface charges of the biochars and Sb at basic pH. A risk assessment (US EPA IWEM) performed using experimental K d for each blend suggests that using soil amendments could reduce leached concentrations at points of concern, which could open additional avenues for ash reuse. [ABSTRACT FROM AUTHOR]

The value of sediment for helping coastal habitats and infrastructure respond to sea level rise is widely recognized. Across the country, coastal managers are seeking ways to beneficially use sediment sourced from dredging and other projects to counter coastal erosion and protect coastal resources. However, these projects are difficult to permit and have been slow to actualize. This paper draws on interviews with sediment managers and regulators in California to explore the challenges and opportunities for habitat restoration and beach nourishment within the current permitting regime. We find that permits are costly, difficult to obtain, and sometimes stand as a barrier to more sustainable and adaptive sediment management. We next characterize streamlining approaches and describe entities and ongoing efforts within California that apply them. Finally, we conclude that to keep pace with coastal losses due to climate change impacts, efforts toward efficient permitting must be accelerated and approaches diversified to support coastal resilience practices state-wide, in a timeframe that will allow coastal managers to innovate and adapt. [ABSTRACT FROM AUTHOR]

To improve water use efficiency and productivity, particularly in irrigated areas, reliable water accounting methodologies are essential, as they provide information on the status and trends in irrigation water availability/supply and consumption/demand. At the collective irrigation system level, irrigation water accounting (IWA) relies on the quantification of water fluxes from the diversion point to the plants, at both the conveyance and distribution network and the irrigated field level. Direct measurement is the most accurate method for IWA, but in most cases, there is limited metering of irrigation water despite the increasing pressure on both groundwater and surface water resources, hindering the water accounting procedures. However, various methodologies, tools, and indicators have been developed to estimate the IWA components, depending on the scale and the level of detail being considered. Another setback for the wide implementation of IWA is the vast terminology used in the literature for different scales and levels of application. Thus, the main objectives of this review, which focuses on IWA for collective irrigation services, are to (i) demonstrate the importance of IWA by showing its relationship with water productivity and water use efficiency; (ii) clarify the concepts and terminology related to IWA; and (iii) provide an overview of various approaches to obtain reliable data for the IWA, on the demand side, both at the distribution network and on-farm systems. From the review, it can be concluded that there is a need for reliable IWA, which provides a common information base for all stakeholders. Future work could include the development of user-friendly tools and methodologies to reduce the bridge between the technology available to collect and process the information on the various water accounting components and its effective use by stakeholders. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering & Architectural Faculty of Eskisehir Osmangazi University / Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In many parts of the world, ports and harbours lie adjacent to ecologically important areas of coastal habitat. In such areas port authorities, coastal managers and regulators are required to negotiate the tension between the demands of making ports ever more efficient, with wider and deeper approaches to accommodate vessels of deeper draft and larger handling areas, and the preservation of coastal habitats which are vitally important for bird and fish populations and which help protect the coast from flooding and erosion. The deepening of approach channels and berths usually results in an increased rate of sedimentation and maintenance dredging. There is an increasing recognition that such dredged sediment is a resource which should be utilised beneficially for human development activities and/or enhancement of ecological habitats. One form of beneficial use of dredged material, is termed “sediment recycling” or “strategic placement”. This form of beneficial use consists of the placement of cohesive sediment into the water column or onto the bed in such a way so that currents and waves then transport the released sediment onto the desired habitats. Sediment recycling is less widely practiced because the changes in bed level resulting from placement are generally of the order of a few centimetres/year or less and it is difficult to demonstrate whether such recycling is successful. This paper describes a methodology for the assessment of the effectiveness sediment recycling, implementing the methodology on a case study of a large-scale sediment recycling scheme in the Stour/Orwell Estuary system in the United Kingdom, designed to offset the identified adverse effects of an approach channel deepening on the estuary system. The study represents a major contribution to the consideration of non-direct beneficial use of cohesive sediment. For the first time a methodology for reliably evaluating the effects of sediment recycling, separating the effects of natural changes in morphology from the beneficial use, has been shown to be effective. This method, which is applicable anywhere where there are sufficient data, allows a robust evaluation of the effectiveness of such methods and crucially enables these methods to be tested and optimised using modelling before implementation.

Tidal marshes are important sites of silicon (Si) transformation, where dissolved Si (DSi) taken up by macrophytic vegetation and algal species is converted to biogenic silica (BSi), which can accumulate in the soil, be recycled within the marsh, or be exported to adjacent coastal waters. The role of restored and created tidal marshes in these processes is not well understood, nor is the impact of nutrient enrichment at either the plant or ecosystem level. Here, Si fluxes were examined to develop a Si mass balance in a nitrogen (N)-enriched marsh created with fine-grained dredged material from the Chesapeake Bay, United States. In addition, the effectiveness of Si soil amendments to ameliorate the negative effects of excess nitrogen on Spartina alterniflora was examined through laboratory and field experiments. Silicon was exported to the estuary as DSi (49 g m−2 y−1) and BSi (35 g m−2y−1) in stoichiometric excess of nitrogen and phosphorus. Rapid recycling of Si within both marsh and the tidal creeks appeared to be important in the transformation of Si and export from the marsh. Enhanced macrophyte SiO2 tissue concentrations were observed in the field experiment, with end-of-season mean values of 2.20–2.69% SiO2 in controls and 2.49–3.24% SiO2 in amended plots, among the highest reported for S. alterniflora; however, improved plant fitness was not detected in either experiment. Thus, tidal marshes created with a fine-grained, N-rich dredged material appear to function as a rich source of Si to the restored marsh and local estuarine environment, an overlooked ecosystem service. Soil Si amendments, however, did not appear likely to alleviate N-induced stress in S. alterniflora.

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ecological integrity has been criticized as a "bad fit as a value" for conservation biology and restoration ecology. But work over the past four decades centered on ecological integrity—especially biological integrity—has given rise to effective methods for biological monitoring and assessment to better understand the disintegration of living systems, including under scenarios of rapid climate change. Revealing when and where living systems have been altered by human activity, such methods have been adapted and applied most comprehensively in streams and rivers, but also in other ecosystems, ranging from tropical forests to marine coral reefs and on all continents except Antarctica. Equally important, restoration and maintenance of biological integrity is already a fundamental goal in law and offers an inspiring framework for communication and engagement—among scientists, resource managers, law‐ and policymakers, and the public. This essay builds the case that ecological integrity has proved both real and valuable as a conservation paradigm. [ABSTRACT FROM AUTHOR]

The use of natural habitats for coastal protection (also known as Nature‐Based Solutions or NBS) in place of engineered structures like breakwaters and seawalls can yield a wide range of ecological and economic benefits. Despite these advantages, NBS are not commonly implemented for shoreline protection due to uncertainty over the amount of protection afforded by each unique feature and how protective capacity and ecological benefits are likely to change over time as NBS mature and adapt to changing environmental drivers. Here, we highlight the recent restoration of Swan Island in the Chesapeake Bay, Maryland, USA, and the collaborative approach used to evaluate post‐construction performance, as a framework for quantitative evaluation of NBS projects. At Swan Island, 60 000 cubic yards of dredged sediment were used to elevate and restore the island's footprint with an emphasis on increasing its protective and ecological benefits and long‐term resilience to sea‐level rise. Five entities have leveraged resources to quantify the benefits and efficacy of island restoration by conducting pre‐ and post‐restoration monitoring, which supports the development of an integrated, simulation model that includes three "measured" system parameters: wave height, vegetative biomass, and island profile (i.e., elevations). The model will be used to predict island performance under a range of different system scenarios and used to inform adaptive management options. Results will demonstrate the efficacy of leveraging natural and engineered processes to restore island systems while providing a framework for quantifying NBS. Integr Environ Assess Manag 2022;18:42–48. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by US Government employees and their work is in the public domain in the USA. KEY POINTS: Evaluations of NBS performance at the scale of the individual project are needed to address uncertainties about when and where natural solutions can afford adequate levels of coastal protection. A consistent approach to NBS project evaluation will help to foster confidence in the use of natural approaches. [ABSTRACT FROM AUTHOR]

Hierarchical porous carbon (HPC) materials contain organized pores having different scales of diameters. These materials exhibit surprisingly high performance in various applications due to the functional combination of hierarchical pores. This paper reviews the preparation of HPC from waste and biomass, and their potential applications. Biomass with naturally organized hierarchical structure, such as wood, grass and nut shell, have been widely used as raw materials, from which, hierarchical porosity can be formed through simple pyrolysis-activation. Influences of the types and dosages of activating agent, as well as the pyrolysis/activation conditions on the specific surface area, pore volume and hierarchical porous structure of the structured biomass-based HPC are discussed. For non-structured raw materials such as sucrose, pitch and plastics, novel technologies have been developed to prepare HPC; these include hard-/soft-template methods, hydrothermal carbonization, chemical vapor deposition, spray pyrolysis and autogenic pressure carbonization. The approaches to design or control the structures and properties of HPC made from non-structured materials are also reviewed. Moreover, advanced applications of HPC in energy storage, deionization, adsorption and catalysis are summarized. [ABSTRACT FROM AUTHOR]

Beneficial use of dredged sediments, either in harbours or waterways, is based on their potential as alternative resources. Such sediments can be considered as bulk materials for industrial needs, which is predicated on their current waste status or meeting end-of-waste constraints. They also can be an integral part of beneficial use projects using sediments as a bulk component, including civil engineering and landscaping. This is particularly important for beneficial use projects focusing on climate change effects mitigation, such as flood protection works, coastline defence or littoral urban areas redevelopment. When dredged sediment is used as a bulk material, its acceptability is based on an assumed homogeneity of its properties. On-site analyses allow pre-dredging detailed mapping at a denser scale than laboratory ones; monitoring dredgings during operations and during processing; and continuous control of their properties at the implementation site. This is currently possible only for a selection of inorganic analytes. When dredgings are part of a larger beneficial use project, on-site analyses facilitate first the baseline survey and the sediment source characterisation. Continuous monitoring of the sediment load allows a fast detection of contamination hot spots and their adequate management. Site survey via on-site instruments allow end users and communities to check themselves the contamination level, hence acceptability is better. On-site dredged sediment analyses monitor both building properties and environmental compliance; soil and sediment analyses at receiving sites; surface and groundwater, either for impact assessment or for monitoring works. On-site instruments provide immediate results and allow dynamic or adaptive sampling strategies, as well as allowing operational decisions in real time. Confirmation by laboratory analyses is required for validation, but on-site sample screening for laboratory analyses improves their efficiency. The present paper was developed on the basis of an earlier presentation, which it developed and updated extensively.

Bu çalışma, dip taramafaaliyetleri neticesinde ortaya çıkan dip tarama malzemelerinin (DTM) betonuygulamalarında ince agrega olarak faydalı kullanımı için bir yıkama-elemetesisi tasarlanmasını, bu tesise ait ilk yatırım ve işletme maliyetlerininortaya konulmasını ve laboratuvar ölçekli DTM yıkama-eleme denemeleri sonucundaortaya çıkan atıksuyun karakterizasyonunun ve yönetiminin belirlenmesini kapsamaktadır.Bu çalışma ile DTM’nin yıkama-eleme ön işlemine tabi tutulması durumunda yüksekklorür, sülfat ve su içeriğinin giderilerek ince agrega olarak betonçalışmalarında kullanılabileceği, oluşan yıkama-eleme atıksuyununkanalizasyona/denize deşarjına risk oluşturacak herhangi bir kirleticiiçermediği tespit edilmiş olup olası 1.500 m3/gün kapasiteli DTMyıkama-eleme tesisinin ilk yatırım ve işletme maliyetlerinin sırasıyla6.753.600 TL ve 2.366.810 TL ve birim maliyeti ise 6,3 TL/ton olarakhesaplanmıştır.

With rising seas come several challenges for our coastlines, including the need to maintain waterways, ports, and harbors; military and infrastructure resiliency; and the protection of valuable coastal ecosystems. This technical note examines coastal resiliency needs and challenges along America's four coasts - Great Lakes, East, Gulf and West coasts, with a review of select case studies. Latest tools for resiliency and adaptation planning are reviewed and presented. Undoubtedly, there is a need for regulation to promote beneficial use of dredged sediments to improve coastal resiliency, including, but not limited to, aligning navigational dredging schedules with coastal protection needs. Permitting of these projects can be challenging as projects are typically reviewed by regulatory agencies as "disposal" or "placement" projects, as opposed to ecosystem restoration projects, which provide a distinct ecological uplift benefit. Quantification of benefits resulting from resiliency projects continues to be an area that needs more analytical tools and project data. The paper concludes with a discussion of future directions, including areas of additional research, and data gaps. [ABSTRACT FROM AUTHOR]

In this paper, a screening‐level life cycle assessment (LCA) approach is used to compare the potential environmental benefits and tradeoffs of different management options for wood ash, namely, agricultural land application, forest soil amendment, use in forest roads, use in concrete and mortar, and landfilling. Uncertainty analyses are used to evaluate the generalizability of the results obtained. Although decisions regarding the selection of a beneficial use option are site‐specific and depend on available local markets and wood ash characteristics, this study shows that it is possible to draw a few general conclusions from the application of LCA. All beneficial use (BU) options showed lower environmental indicator scores than those associated with landfilling, in addition to net potential environmental benefits. From an environmental perspective, results suggest that, only in a few situations, beneficially using wood ash might not produce potential net environmental benefits but would still be preferred over landfilling, and in a very few cases, landfilling would be preferred over a BU option. For instance, net environmental benefits may be compromised if wood ash needs to be transported over long distances before it can be beneficially used. Out of the four BU options evaluated, the use of wood ash in concrete to replace Portland cement showed the greatest potential environmental benefits. However, the application of wood ash on agricultural or forest land showed greater environmental benefits than the use in concrete in cases where both its liming and fertilizing potentials are assumed to be achieved at the same time. [ABSTRACT FROM AUTHOR]

Purpose: Contaminated sediments in rivers, lakes, and harbors around the world result in diminished ecological health, degradation of environmental resources, economic losses, and, in rare cases, impacts on human health. Despite the ongoing interest in the cleanup of contaminated sediments in rivers and harbors, little progress has been made in reducing the number of contaminated sites worldwide. Proponents of a "circular economy" model assert that it can facilitate the cleanup of contaminated sediments through product and process design to eliminate waste of resources, to beneficially use (and reuse) products and materials, and to restore ecologies. This paper evaluates the application of circular economy models to practice in the treatment, removal, and processing of contaminated sediments found in waterways. Materials and methods: No materials were used in this work. Methods consisted of literature research and review. Results and discussion: Much of the difficulty in advancing the cause of contaminated sediment cleanup can be attributed to the high cost of cleanups and the difficulty in assigning financial responsibility for the cost. Simple schemes dependent on identifying polluters are fraught with underlying complexity. More elaborate approaches tied in with waterfront redevelopment show some promise but are yet to be applied routinely. New advances in the understanding of how sediments may, or may not, factor into the utility of circularity models pose new challenges and opportunities, with the potential to complement new funding paradigms. Conclusion: The most promising possibilities for achieving circularity in sediment management lie in a kind of punctuated circularity, which requires individual, project-based beneficial use opportunities. However, these ideal situations are likely to remain rare for the foreseeable future, without advancements in technology and regulatory approaches, as well as development of market demand for the products made from contaminated sediments. [ABSTRACT FROM AUTHOR]

Yangon river has been facing with a problem of high rate of sedimentation as the reasons of deforestation, riverbank erosion, and flooding. A hundred million tons of sediments has been being dredged over 50 yr to maintain Yangon river waterway. Sediments daily produced from dredging work are directly dumped at a designated disposal area about 200 m far from dredging site to flash out these sediments by strong river flow. It may increase disposal-related turbidity disturbing sediment-settling into riverbed, and perhaps have a tendency to re-accumulate these materials into original dredging site because of the complex river flow at dredging site, known as inner bar area, where is close to a confluence of rivers and creek. This paper examines how to minimize the dredged amount at inner bar area by means of beneficial use. Therefore, sediment characteristics are needed to analyze because fine-grained sediments can easily attach pollutants giving an adverse effect to marine environment. Sediment samples from three different locations around inner bar area were collected with hand corer by diver, and analyzed U.S EPA methods: 10 129, 10 067, and 8000 for organic matters, inductive coupled plasma mass spectrometer for heavy metals, gas chromatography with mass spectrometer for persistent organic pollutants, and laser diffraction particle size analyzer. 14% of sand, 32% of silt, and 54% of clay were determined. The water contents in samples were 40.73%, 40.28%, and 31.40%. Lower values of harmful pollutants in samples than international standards were found. Therefore, sediments from inner bar may be supposed non-contaminated ones giving a better quality applied for beneficial use. Thus, without additional pollution-control treatments, appropriate technologies such as particle separation and dewatering techniques are described to produce commercial products, and to apply for engineering uses and environment enhancement as a sustainable practice. [ABSTRACT FROM AUTHOR]

The remediation of contaminated aquatic sediments requires a range of expertise from assessment (investigation, risk evaluations, modeling, and remedy selection) to design and construction. Research in 2019 has added to knowledge on optimizing the use of passive samplers for assessing chemical concentrations in sediment porewater. The porewater and black carbon appear to be better predictors of contaminant bioaccumulation than total organic carbon alone. This has led to better characterization of potential risk at sediment sites. Tools to identify and model sources of chemicals have been developed and used particularly for some metals, polynuclear aromatic hydrocarbons and polychlorinated biphenyls. There is great emphasis on beneficially using dredged sediment, treating it as a resource rather than a waste. Amendments used in sediment caps continue to be refined including the use of activated carbon within the caps and by itself. A technique involving 16S rRNA has been established as a means of identifying microbiological composition that naturally degrade contaminants. © 2020 Water Environment Federation Practitioner points: Sediment capping technology continues to advanceSampling and testing methods continue to be refinedNatural processes such as biodegradation are being better understoodBeneficial use of dredged sediment continue to be emphasized [ABSTRACT FROM AUTHOR]

This work examines polycyclic aromatic hydrocarbon (PAH) concentrations in yard trash at various stages of the yard trash management cycle of collection, stockpiling, grinding and screening into mulch, and composting. Total extractable PAH concentrations were measured in yard trash at various management stages from 10 locations in Florida. The concentrations of 16 PAH compounds in processed yard trash ranged from 0.38 to 14 mg kg-1. PAH concentrations were detected in vegetative material harvested from a residential neighborhood, but were below the United States Environmental Protection Agency residential regional screening levels (RSLs). PAH concentrations near or above the RSLs were common in both unprocessed and processed yard trash collected at waste management facilities. PAH concentrations were amongst the highest in newly ground yard trash samples and were amongst the lowest in composted yard trash samples. These findings are important because land application of some waste materials, such as construction and demolition debris fines and street sweepings, are sometimes limited due to PAH. If processed yard trash, which is commonly land applied in residential settings, possesses similar PAH concentrations, evaluation of current risk assessment practices for land-applied wastes may require further examination. [ABSTRACT FROM AUTHOR]

• Marine dredged materials of Marmara Sea taken from five pilot areas were analyzed. • Environmental tests classify the samples of dredged sediments as non-hazardous waste. • Beneficial use of dredged material in landfills were evaluated by geotechnical tests. • Raw or processed dredged material is applicable as cover, barrier or restoration layer. • Beneficial use is cheaper than terrestrial disposal, and ecologically more sustainable than dumping at sea. Worldwide production of large volumes of dredged materials (DMs) has become a pressing environmental problem. In Turkey, the government has yet to develop management strategies that successfully prevent or minimize dumping into the Marmara Sea. One potential solution is the utilization of the DMs as a source of material for earthworks, particularly in sanitary landfills in Istanbul and Kocaeli. The most economically developed cities in Turkey, they were evaluated in terms of potential environmental impacts and regulatory compliance. Five ports/harbors representing specific portions of the study area and different industrial activities were selected as pilot regions. Physical, chemical, mineralogical, toxicological, and leaching potential measurements of DMs dredged from the seabed revealed they qualify as non-hazardous waste. Index and engineering tests performed on raw and processed DMs were assessed to determine the geotechnical requirements for soil-based materials (SBM) used in sanitary landfills. The results showed that non-hazardous DMs could be utilized as a cover, base/cap liner, and/or fill material at various sections within the landfills. This method provides environmental advantages not seen with other management strategies for DMs such as dumping at sea or upland disposal. [ABSTRACT FROM AUTHOR]

Purpose: Climate change necessitates heightening and strengthening of dikes, requiring large volumes of suitable soil. This study investigated soil ripening and long-term development of hydraulic behaviour of a dike constructed from slightly contaminated, partially dewatered dredged material from the Port of Hamburg under realistic conditions of construction and operation. Materials and methods: Two test fields of 126 m2 each were constructed in 2004 for long-term analysis of hydraulic behaviour in combination with the possible mobilisation of contaminants. In test field 1 (MS), the 1-m-thick cover above the sand core consisted of traditionally used alluvial marsh sediment (reference), while in test field 2, the lower 0.7 m of the cover was substituted with dredged material (DM + MS). An HDPE tray below each field served the collection of bottom fluxes and hence the quantification of discharges and analysis of their chemical composition. In 2012, an excavation was carried out to inspect the development of the soil structure. Results and discussion: The discharge pattern revealed three distinct phases related to the post-construction structure development and therefore physical ripening of the soils. Within a single year, bottom fluxes typically started in mid-winter and ended in late spring. The dike cover containing DM had a high water retention capacity; however, the vertically continuous primary shrinkage cracks led to higher total bottom fluxes compared to the dike constructed from MS only. System hydraulic conductivities increased by up to six orders of magnitude compared to the as-built condition before soil ripening and structuring. The dredged material maintained a reduced geochemical status for about two years after construction. After first shrinkage and intrusion of oxygen, the material changed to an oxidised state, earmarking the onset of the chemical ripening process. Oxidising conditions were sustained in the long term, seen from the absence of previously elevated ammonium concentrations in the dike seepage. Conclusions: System hydraulics of the test field with dredged material were mainly determined by the covering layer of marsh sediment. After construction, the dredged material underwent physical, chemical and biological soil ripening processes, coupled to a respective change in discharge patterns, which, however, did not impair dike stability. It is recommended that soil ripening processes are induced and completed as part of the material's pre-treatment, precluding the formation of irreversible shrinkage cracks and changeover of redox conditions after construction. The findings contribute to assessing the feasibility of the beneficial use of dredged material. [ABSTRACT FROM AUTHOR]

The Dredged Material Decision Tool (DMDT) was developed by the United States Environmental Protection Agency (USEPA) to allow project managers, stakeholders, and communities to quantify environmental, economic, and social considerations of using dredged material for beneficial purposes. Dredged material may be disposed in a confined disposal facility (CDF); however, this option is unfavorable because of the finite capacity problems these facilities pose. A more sustainable option is to use dredged materials beneficially such as construction material, for habitat restoration, or for brownfield remediation projects. This study demonstrates the applicability of the DMDT to three relevant candidate projects: (1) Dog Beach, Greenwood, and Lee Street Beaches (Evanston, IL, USA); (2) New York-New Jersey Harbor (New York/New Jersey); and (3) Poplar Island (Chesapeake Bay). The DMDT requires the project information and then completion of worksheets with each criteria (biophysical environment, economic, governance, social, and built environment) ranked, weighed, and scored. The DMDT is applied for all potential alternatives and the results are then analyzed to select the best beneficial reuse alternative. It was found that for the beaches in Evanston, the most beneficial option was on-beach placement with hydraulic dredging. The best option for the New Jersey Harbor was found to be using for brownfield and landfill remediation. The best option for Poplar Island was the lateral and vertical expansion of 50% uplands and 50% wetlands. Overall, DMDT is found to be a valuable tool to facilitate the evaluation of multi-criteria based on the project-specific data and help select the best beneficial use alternative for the dredged material.

Tidal marsh restoration using dredged material is being undertaken in many coastal areas to replace lost habitat and ecosystem services due to tidal marsh loss. The fate of high levels of nitrogen (N) in fine-grained dredged material used as a substrate for marsh restoration is uncertain, but if exported tidally may cause subtidal habitat degradation. In this study, a mass balance was developed to characterize N fluxes in a two-year-old restored tidal marsh constructed with fine-grained dredged material at Poplar Island, MD, in Chesapeake Bay, and to evaluate the potential impact on the adjacent submersed aquatic vegetation (SAV) habitat. Denitrification and N accumulation in Spartina organic matter were identified as the major sinks (21.31 and 28.5 mg N m−2 d−1, respectively), while tidal export of TN was more modest (9.4 mg N m−2 d−1) and inorganic N export was low (1.59 mg N m−2 d−1). Internal cycling helped retain N within the marsh. Mineralization of N associated with labile organic matter in the dredged material was likely a large, but unquantified, source of N supporting robust plant growth and N exports. Exceedances of SAV water quality habitat requirements in the subtidal region adjacent to the marsh were driven by elevated Chesapeake Bay concentrations rather than enrichment by the marsh.

As known, marine dredged materials (DMs) are highly nuisance wastes if they are not correctly reused or removed. In this work, the usability of DMs to the technical terms as manufactured topsoil (MT) in the urban landscaping works is discussed. Firstly, the leaching potentials of DMs were determined according to the related legislations to identify their hazardousness features. Secondly, DMs were subject to some treatment stages such as sieving, desalination, organic amelioration via peat and sheep manure, and pH adjustment to turn into an alternative natural soil pursuant to the British Standard in the scope of soil quality improvement studies as there is not any national standard in Turkey for the production of topsoil from different materials. Then, MT mixtures were prepared with washed and unwashed DM, peat and sheep manure in different mixing ratios (v/v); 33%, 50% and 67% DM, respectively. Consequently, high quality grass seed mixtures used for the landscaping applications were monitored for six months. The results demonstrate the availability of DM as alternative MT in the urban landscaping areas. Thus, important data were obtained as to the use of DM at alternative areas such as green city, green roof, shopping centers, organized industry, etc.

• Municipal waste incineration (MSWI) ash investigated as a mineral feed in cement. • MSWI ash forms viable clinker but is limited by chloride and alkali content. • This practice is economically advantageous for generators and manufacturers. • MSWI ash recycling to cement is a valuable recycling opportunity. Municipal solid waste incineration (MSWI) ash has the potential to be used as mineral feed for portland cement manufacture but is not currently used in this manner in much of the world. A scoping study was performed using samples and data from Florida, US, to assess the potential magnitude of material that may be recycled to create a viable clinker. Results indicate that MSWI ash possesses the elemental ingredients to serve as a partial kiln feed replacement. Large amounts of MSWI can be used based on mineralogy alone, but chloride and alkali content limitations decrease allowable replacement amounts, especially for fly ash. Average allowable replacement percentages that did not exceed standard chloride and alkali limits were 6.4%, 0.33%, and 1.17% for bottom ash, fly ash and combined ash, respectively. MSWI bottom ash may be the preferred material stream in the absence of pre-processing techniques such as washing. The scoping study found that available MSWI ash could supply a large amount of the current kiln feed demand, and a feasibility and cost assessment supports that both MSWI facility and cement kiln operators have justification to pursue this technology with more detailed evaluations. [ABSTRACT FROM AUTHOR]

The use of municipal solid waste incinerator bottom ash for road-base construction is an accepted practice in Europe and Asia, and of growing interest in the US. It is common practice to cure bottom ash by stockpiling it for several weeks before using it in this application. The curing process exposes the bottom ash to atmospheric carbon dioxide, which promotes carbonation, lowering its pH (making it less alkaline), and making many heavy metals less soluble. While this process makes bottom ash a more environmentally acceptable material, it takes time and requires additional handling. This article investigates a concept to facilitate carbonation of bottom ash in its compacted state, potentially eliminating the stockpile curing process. It is demonstrated here that blending a small amount of organic material with bottom ash will accelerate carbonation and lower pH in compacted samples by providing a carbon source for bacteria to produce carbon dioxide. Different quantities of biosolids (1%, 2%, 3%, and 5% by mass) were added to compacted bottom ash samples to examine the effect of organic materials on carbonation, and results were compared with a compacted control bottom ash sample. The pH of the control bottom ash sample decreased from 12.07 to 9.78 after 63 days, while the pH of the sample containing 5% biosolids decreased from 11.70 to 9.74 in only 7 days and to 8.18 after 63 days. Physical testing was conducted to examine suitability for beneficial use. The results indicate that bottom ash containing less than 3% biosolids met minimum bearing strength requirements for road base. [ABSTRACT FROM AUTHOR]

Nowadays, sustainable environmental management of high quantities of marine dredged material (DM) together with other industrial wastes is a common problem across Turkey. The beneficial use/recovery of DM and wastes in the production of lightweight aggregate (LWA) instead of dumping at sea/disposal will provide substantial environmental savings in terms of circular economy. In this study, the production of LWA by using marine DM, coal fly ash and waste foundry sand were investigated. Three different mixtures of raw materials were granulated in pelletizing disc, dried at 105°C and sintered in muffle furnace at 1100, 1150, 1170, 1180 and 1190°C with 5-10°C/min heating rates and 10-20 min sintering period. Sintered LWAs were analyzed in terms of physical, mechanical, microstructural, mineralogical and leaching properties. LWA produced at 1190°C sintering temperature, 5°C/min heating rate and 20 min sintering period resulted in better aggregate properties. Furthermore, according to the leaching test results; it is observed that the parameters of the eluate and original waste were lower than the Class III (inert waste) landfilling limit values due to the entrapment of those into the silicate matrix in sintering process; thus, causing no environmental risk to be used at construction sector. [ABSTRACT FROM AUTHOR]

• Increased PG production demands a sustainable alternative disposal scenario. • PG-aggregate base blends reduced total and leachable constituent concentrations. • Total and leachable concentrations from blends vary with source and aggregate. • Blending provides a more chemically suitable base material than PG alone. • Valorization of PG as a construction material enhances sustainability. Interest in reuse of phosphogypsum (PG) road base materials has resurged as alterative disposal to stacking, but is limited due to regulatory constraints surrounding chemical composition and mobility. Prior to implementation of a waste product, direct exposure and leaching-to-groundwater risk should be determined, however the chemical behavior of PG blended with other base materials has not been thoroughly investigated. The total and leachable concentrations of trace metals, anions, and radionuclides from several PG sources, common base aggregates, and PG-aggregate blends were assessed. Between PG samples, older PG leach lower As, Sr, Mo, and fluoride than newer from the same facility. Blending PG with aggregates reduced total and leachable concentrations of interest for at least one blend, attributed to decreased PG content, change in pH, or addition of binding minerals. Blending PG with limerock or recycled concrete aggregate reduces direct exposure and leaching-to-groundwater risk, expanding opportunities for PG reuse. [Display omitted] [ABSTRACT FROM AUTHOR]

• Phosphogypsum (PG) has been investigated as a road base supplement. • Chemical performance of PG varies based on source, wet process, and aging conditions. • Behavior of chemical constituents should be monitored for specific PG reuse opportunities. • Blending or stabilizing PG with alkaline materials for base affects element mobility. • Laboratory and pilot-scale chemical analysis of PG amended road base is limited. The use of phosphogypsum as an amendment to graded aggregate road base serves as an alternative to traditional and recycled aggregate sources. This provides a solution to issues currently faced by the phosphoric acid industry due to limited recycling opportunities, aggravated by a lack of understanding of variability in phosphogypsum due to source, location, and process worldwide. This manuscript provides a comprehensive overview of the chemical differences in phosphogypsum from around the globe and discusses the opportunities and challenges associated with phosphogypsum-amended road bases. The literature reveals that although mineralogical composition between sources remains similar (calcium sulfate), the total and leachable constituent concentrations vary significantly between facilities worldwide, impacting applicability and behavior as a road base material. Different approaches include using phosphogypsum as a base material alone, blended with aggregate, or stabilized and several studies report physical and environmental success, although thorough environmental monitoring of pilot-scale risk is lacking. [ABSTRACT FROM AUTHOR]