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Upland placement of dredge sediments has the potential to provide beneficial reuse of suitable sediments for agricultural uses or urban soil reconstruction. However, the use of many dredge materials is limited by contaminants, and most established screening protocols focus on limiting major contaminants such as heavy metals and polycyclic aromatic hydrocarbons and generally ignore fundamental agronomic parameters. Since 2001, we have placed over 450,000 m of Potomac River fresh water dredge materials and 250,000 m of saline materials from various locations into monitored confined upland facilities in Charles City, VA, and documented their conversion to agricultural uses. Groundwater and soil quality monitoring has indicated no adverse effects from material placement and outstanding agricultural productivity for the freshwater materials. Once placed, saline materials rapidly leach and ripen with quick declines in pH, electrical conductivity, and sodicity, but potentials for local groundwater impacts must be considered. Our experience to date indicates that the most important primary screening parameter is acid-base accounting (potential acidity or lime demand), which should become a mandatory analytical requirement. Our second level of acceptance screening is based on a combination of federal and state residual waste and soil screening standards and basic agronomic principles. High silt+clay and total organic C may also limit rapid use of many dredge materials due to extended dewatering times and physical limitations. This dredge material screening system separates potential upland placement candidates into three soil quality management categories (unsuitable, suitable, and clean fill) with differing monitoring requirements. Similar use of these sediments in urban soil reconstruction is also recommended.

On a surface coal mine in southern West Virginia, the forestry reclamation approach was applied while quantifying the effects of substrate type and seeding prescription on survival and growth of native tree species and herbaceous vegetation. Four substrates were used: weathered sandstone (brown), unweathered sandstone/shale mix (gray), mixture of weathered and unweathered rock (mixed), and a mixture of the soil solum and unconsolidated soil parent material (soil). Each substrate treatment was split into two subplots; one seeded with a tree-compatible herbaceous seed mixture and one unseeded. Trees were planted in March 2012, measured for initial height in June 2012, and measured for height and survival in late October 2012. Herbaceous groundcover and species richness were measured during the growing season. After one growing season, mean percent survival and growth of planted trees differed among tree species and seeding treatments. There were no differences in tree survival among substrate treatments. Of planted tree species, survival was higher for hawthorn and black cherry (~85%) than for most other species and lowest for Eastern white pines (25.3%) and shagbark hickory (24.3%). Unseeded treatments had higher tree survival (70.4%) than seeded treatments (56.4%). Of the trees which survived the first growing season, black cherry, red oak, sugar maple, and white oak showed differences in height growth related to experimental treatments. Black cherry and red oak trees grew more in the unseeded treatment, compared to the seeded treatment. White oaks grew the most in the brown sandstone treatment. Sugar maples grew the most in the seeded mixed treatment. Gray and soil substrate treatments had the highest total herbaceous richness and the soil treatment had the highest volunteer richness. Seeded treatments had less bare ground and higher mean herbaceous species richness than unseeded subplots. Leaving the landscape unseeded facilitated tree establishment, but the impact of seeding on the future understory community remains unclear. Soil appears superior to rock spoils for reestablishing a diverse understory. We expect that the influence of substrate and seeding treatments will become clearer after additional growing seasons.

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