Brief Summary of Minutes of Annual Meeting

Objective 1: Evaluate the short- and long-term chemistry and bioavailability of nutrients, potentially toxic inorganic trace elements, and pharmaceuticals and personal care products (TOrCs) in residuals, reclaimed water, and amended soils in order to assess the environmental and health risk-based effects of their application at a watershed scale.

Specific tasks:

• To develop and evaluate in vitro (including chemical speciation) and novel in vivo methods to correlate human and ecological health responses with risk-based bioavailability of trace elements and TOrCs in residuals and residual-treated soils.
• Predict the long-term bioavailability and toxicity of trace elements and TOrCs in residual-amended urban, agricultural and contaminated soils.
• Evaluate long-term effects of residuals application and reclaimed wastewater irrigation on fate and transport of nutrients, trace elements, TOrCs, and emergence/spread of antibiotic resistance in high application rate systems.

(iv)             Evaluate plant uptake and ecological effects of potentially toxic trace elements and TOrCs from soils amended with residuals and reclaimed wastewater.

Objectives 1 Accomplishments:

Arizona

Following wastewater treatment, dewatering of biosolids at Tres Rios WWTP in Tucson Arizona results in ≃ 0.5 mgd of effluent with high concentrations of NH₄ (1000 ppm). This effluent is returned to the head works, and the high NH₄ concentration results in a need for extra oxygen to be pumped into the effluent to enhance nitrification. This results in significantly enhanced energy costs (= 30% total energy costs). Therefore, there is a need to remove the NH₄ prior to re-entry into the head works. A project started by Pepper et al. evaluates an alternative method of removing the NH₄ from the effluent – namely anaerobic oxidation of ammonia or anammox. Anammox relies on a consortium of autotrophic bacteria to oxidize NH₄ utilizing nitrite as a terminal electron acceptor. They are evaluating the efficacy of anammox as an alternative side stream treatment of effluent, and also determining the influence of anammox on human pathogenic virus inactivation.

The primary goal of the project is to develop a real-world anammox technology for sidestream treatment of effluent with high ammonia concentrations. This will involve scale-up of existing bacterial cultures.

• 3L batch consortium ® C 120 L bioreactor ® full-scale-real-world treatment at Tres Rios

A secondary goal of the project is to evaluate the incidence of human pathogenic virus in the dewatered water, and potential inactivation by the anammox process and high ammonium concentrations. Specifically quantitative polymerase chain reaction (qPCR) and cell culture (cc) will be utilized to detect the following viruses in food, water and effluent water:

• Pepper mild mottle virus (qPCR)
• Enterovirus (qPCR and cc)
• Adenovirus (qPCR and cc)
• Reovirus (qPCR and cc)

Data from this part of the study will quantify the viral load associated with the dewatering process.

Currently two 120L bioreactor have been constructed. This has entailed sophisticated technology to enable aerobic bacteria (Nitrosomonas) and anaerobic bacteria (anammox) to co-exist in close proximity. This is achieved through granular formation of bacteria or biofilm formation on plastic discs. Preliminary data has been obtained on key chemical and biological parameters. To date amonnium removal has varied between 35 and 85%.

Colorado

Ippolito et al. continued investigating the long-term benefits of biosolids land application to dryland winter wheat-fallow and a dryland winter wheat-corn-fallow agroecosystems under minimum tillage.  As with past reports, they observed that crop uptake coefficients for nutrients and trace metals in biosolids amended soils were much lower than those used for risk analysis by USEPA.  Biosolids apply metals to soils, with the largest metal concentrations being Cu and Zn.  Biosolids land application to dryland agroecosystems appears to concentrate Cu and Zn in the soil surface, however, little to no appreciable downward movement has occurred even after 20 years of biosolids land application.  They have found that Zn addition may be beneficial in semi-arid cropping systems, such as those found in eastern Colorado, as plant-available soil Zn soil concentrations may be borderline in terms of inducing Zn deficiency symptoms.

They completed several biochar soil-application projects pertaining to heavy metal sequestration and sorption/degradation of organic contaminants. Specifically, they focused attention on wheat straw biochar sorption of Cd in a Cd-contaminated soil from China, converting Cd to less bioavailable forms as noted via sorption, wet chemical sequential extraction, and XAS analyses.  They moved from a benchtop to a greenhouse study, using poultry litter biochar, beef cattle manure biochar, and cattle manure to reduce bioavailable Cd and Zn in a contaminated soil, enhancing switchgrass growth.  They moved from a greenhouse study to a field study, using gasified coniferous wood biochar to reduce Cd, Cu, and Zn bioavailability and allowing for coniferous tree growth on site.  They further investigated the utility of wheat straw biochar to capture and accelerate 2,4,6-TCP degradation, and wheat straw biochar to capture/accelerate organic halogen degradation and enhance reed growth.

Florida

Greenhouse studies were conducted by O’Connor et al. to assess plant uptake and phytotoxicity potentials of CIP and AZ. The plants studied represent a range of terrestrial crops with different morphologies and physiologies and different exposure scenarios to the target TOrCs; all of which could affect chemical uptake and toxicity. Plant uptake of, and toxicity from, biosolids-borne CIP and AZ were negligible even in a worst-case scenario (i.e., sand as a growth medium) and in the presence of uppermost end of environmentally relevant chemical concentrations. The findings are consistent with our hypothesis of limited compound bioavailability due to extensive retention and limited release from biosolids described in last year’s report. The study employed only one biosolids, and different biosolids could exhibit different retention/release (bioaccessibility) behaviors. However, a variety of plants (representing food-chain crops and pasture grass) showed negligible response to a wide range of concentrations of the biosolids-borne compounds. Thus, present data suggest that several years of land application of biosolids containing typical (~median concentrations, USEPA, 2009) concentrations of the target TOrCs, at 1% or greater agronomic rates, pose de minimis risks to plants; despite assuming no chemical attenuation. Even severely AZ- or CIP-contaminated biosolids pose insignificant risks to plants. Plant data are consistent with our hypothesis that compound retention (and severely limited release) limit biosolids-borne CIP and AZ bioaccessibility and bioavailability to plants and other terrestrial organisms.

Uptake and toxicity potentials of biosolids-borne CIP and AZ to earthworms were assessed primarily under laboratory conditions. Neither compound was toxic to earthworms exposed to environmentally relevant (and much greater) concentrations, but both compounds accumulated in the earthworms. Bioaccumulation factors (BAF values) were about 20 for either compound in non-depurated worms (and independent of three soils studied), but only ~4 (for CIP) and ~7 (for AZ) in depurated worms (again, independent of soils). Predators consume whole worms, which can include excreta. Thus, using BAF values for un-depurated worms, or an average of BAF values for depurated and un-depurated worms, likely represents a conservative 1st Tier assessment of risk. Paired soil and earthworms samples from a field study involving biosolids were graciously supplied by MWRDGC personnel and analyzed, but the data were too limited (by extremely low and highly variable concentrations) to support definitive conclusions.

Potential effects of biosolids-borne CIP and AZ on microbial activity (respiration and genes involved in N and P cycling) were evaluated in a 90 day laboratory incubation study (aerobic conditions). Environmentally relevant concentrations of biosolids-borne CIP and AZ are bioavailable and adversely affect (at least) a few microbes (but only initially) in biosolids and (to a much less extent) in biosolids-receiving soils. The adverse effects are muted from an agronomic viewpoint (e.g., minimal effects on microbial respiration and on genes involved in N and P cycling) and largely overshadowed by benefits from land application of biosolids. Adverse effects of CIP on microbes (although minimal) exceed those of AZ, likely because of greater CIP concentrations in biosolids, and greater potency in the environment. Minimal effects of either TOrC on overall soil/biosolids microbial activity is welcomed news. However, inhibition of bacterial amoA expression indicates that both TOrCs can stress microbes (at least initially). Also, minor chemical concentration-induced increases in antibiotic resistance gene expressions (qnrS, mefE, ermB), possible maintenance (ermB) of resistance genes, and possible antibiotic resistant bacterial enrichment occurred. Present data are insufficient to fully document, but qualitatively support, the notion of stress-induced antibiotic resistance development and spread facilitated by biosolids. Longer term (especially field) studies using various Class A and Class B biosolids and quantitative frameworks are needed to fully assess potential biosolids-borne TOrC impacts on microbial resistance genes.

A tiered integrated risk assessment for biosolids-borne CIP and AZ was conducted using the framework developed by WHO (2001). Similar models were parametrized and used to predict risks from biosolids-borne triclosan and triclocarban. Where applicable, data measured in environmentally relevant scenarios were employed. Limitations of missing data on target organism toxicity and uptake were minimized by using conservative reference doses derived by applying appropriate uncertainty factors. A highly conservative screening level risk assessment involved three biosolids application scenarios: a) BAR₁: a single heavy (at the rate of 100 Mg/ha) application of biosolids containing 95^th percentile concentrations of CIP or AZ, b) BAR₂: 40 y of annual land application of biosolids containing average CIP or AZ concentrations, and c) a highly unlikely scenario: BAR₃: 40 y of annual land application of biosolids containing 95^th percentile concentrations found in USA biosolids (USEPA, 2009). The initial screening identified three pathways of concern: Biosolidsàsoilàplant; Biosolidsàsoilàsoil organism; and Biosolidsàsoilàsoil organismàpredator. Reasonable refinements of the screening level assumptions resulted in negligible estimates of risks in all pathways to both human and ecological health under real-world biosolids application scenarios, and calculation of preliminary pollutant limits. More data are needed to reduce uncertainty in the analysis, but the initial RA suggests that the majority of modern USA biosolids can be freely land applied without CIP and AZ load-tracking requirements. The analysis does not currently include a pathway to address antibiotic resistance development, and long-term field investigations (and more quantitative frameworks to assess associated risks) are needed to address concerns about the issue.

Kansas

Anaerobic membrane bioreactors (AnMBRs) are an emerging environmental biotechnology with the potential to enable municipal wastewater treatment to achieve simultaneous energy- positive treatment and resource recovery. Anaerobic Membrane Bioreactor hold promise to effectively treat wastewater at low temperatures with low energy and nutrient requirements, low sludge production, while generating methane-rich biogas and other nutrient rich products. Together with collaborators from Civil, and Biological and Agricultural Engineering, Hettiarachchi et al. began working on investigating potential of using recovered nutrient products (RNPs) from municipal and agricultural wastewater using an AnMBR platform with minimal energy footprint. Hettiarachchi lab group is performing detailed chemical characterization of the RNPs, and identifying their reaction products and efficiency in different soil types through controlled laboratory and greenhouse experiments. The group is also anticipating to capture the nutrients in a variety of tailored forms by controlling the operating strategy of the nutrient capture system and further purify treated wastewaters and RNPs using additional technologies.

Kentucky

Tetracycline (TET) is commonly used to treat bacterial diseases in humans and chickens (Gallus gallus domesticus), is largely excreted, and is found at elevated concentrations in treated sewage sludge (biosolids) and poultry litter (excrement plus bedding materials). Routine application of these nutrient-and carbon-enriched materials to soils improves fertility and other characteristics, but the presence of antibiotics (and other pharmaceuticals) in amendments raises questions about potential adverse effects on biota and development of antibiotic resistance in the environment. Hazard risks are largely dictated by sorption-desorption and diffusion behavior in amendments.  D’Angelo (Univ. of Kentucky) evaluated these  processes from sorption-desorption equilibrium isotherm and diffusion cell experiments with four types common soil amendments (municipal biosolids, poultry manure, wood chip litter, and rice hull litter) at three temperatures (8 °C, 20 °C and 32 °C). Sorption-desorption equilibrium isotherm distribution constants (K_d) were higher in biosolids (1306-2418 mL g^-1) than other amendments (176-347 mL g^-1), with highest values observed at 20 °C.  Depending on amendment, TET sorption was increased 4-40 times by treatment with alum due to increasing surface bound Al³⁺ and metal bridging between TET and reactive functional groups of amendments. Differences in TET sorption by amendments was strongly explained by an exponential relationship to Mehlich 3 Al³⁺ in amendments (R²=0.94). Effective diffusion coefficients in amendments (D_s) were strongly related to K_d and temperature (R²=0.86). Treatment of organic amendments with alum greatly increased K_d, and would greatly reduce D_s and hazard risks of applying these organic amendments with this antibiotic to soils.

Minnesota

Researchers at University of Minnesota (Jelinski et al.) have been looking at the variability in soil lead bioaccessibility at the household scale in the twin cities.

2018-2019 - Funding Organization: University of Minnesota-Twin Cities Office of the Vice President for Research (OVPR) Grant-In-Aid Program

This project is leveraging an existing archive of physical samples (from total lead surveys across 58 Twin Cities owner-occupied homes in 2015 and 2016 completed by a recently graduated M.S. student) to answer the following scientific questions by analyzing 220 carefully selected samples from their archive:

• How does lead bioaccessibility vary with space and depth across urban household properties in the Twin Cities?
• What soil characteristics predict lead bioaccessibility at the household scale?

They will select a subset of physical samples from an existing 600+ sample household soils archive. This 220-sample subset will be assayed for soil lead bioaccessibility by the PBET, RBALP 1.5 and RBALP 2.5 methods as well as for ancillary soil characteristics such as organic matter, phosphorus, and pH. The subset from this archive will be chosen from 22 of 58 homes, which have moderate to high levels of total lead (200-1000 ppm), and stratified by land use, depth, and distance from buildings and roads. The result will be a novel dataset that will be enable us to constrain both the range in variability of soil lead bioaccessibility at the household scale as well as the soil characteristics, which can be utilized to predict bioaccessibility.  

Jelinski et al. has started a new project in 2017 entitled “Collaborative Evaluation of Ecosystem Services Provided by Urban Agricultural Best Management Practices in the Twin Cities Metropolitan Area.”

2017-2020 - Funding Organization: USDA NCR-SARE Research and Education Grant Project 00067679 

Some of this work will have some synergies with W3170 group focus.

New York

Over 90% of the general popoulation is allergic to urushoil (the compound that cause dermitis), those who compost or otherwise manage poison Ivy or poison oak, compost facility managers.

Extensive literatures searches were completed by Bonhotal et al. at Cornell University on all asects of urushiol, how the rash is contracted, and how the urushiol degrades and be transmitted to others.   Most of the research could not be started until poison ivy had fully emerged in late spring.

On June 12, 2017, they arrived at the Education Center and 4-H Park in Otisville at 8 am. Scouted the grounds for poison ivy, Harvested 3, 1-yard buckets of poison ivy. Leaf and yard waste (partially composted) was delivered to the site at 10 am and unloaded in 2 piles. One sample of poison ivy alone was taken in a glass jar and put on ice for Pile 2. Pile 2 was made at ~11:30 am: Approximately 1 bucket load of leaf and yard waste was laid as a base, 1 bucket load of PI was put on top; the pile was covered with woodchips and more leaf and yard waste to equal 2 bucket. The rest of the PI (about 1 bucket load) was left in a circle for Pile 3. Triplicate samples of each mix (pile 1, 2 and 3) were taken and put on ice for day 0. Temperatures were taken at 2 depths on all 4 sides of each pile. Put a fence around pile 3 and hung signage about the study and cautioning not to touch. Triplicate samples were taken from each pile and put on ice. Temperatures were taken at 2 depths on all sides of each pile

On June 14-15, triplicate samples were taken from each pile and put on ice. Temperatures were taken at 2 depths on all sides of each pile.

• Data loggers were placed in each pile.
• Logger 912861 will be used in Pile 3 - the only probe is in channel 3 - there is 70% battery. It has been set to start recording on 6/20/17 at noon and every 6 hours after that.
• Logger 912856 will be used in Piles 1 and 2 - Probe 4 should go in pile 2 and probe 1 should go in pile 1. There is 63% battery. It has been set to start recording on 6/20/17 at noon and every 6 hours after that.

June 21 through Oct 10, triplicate samples were taken from each pile and put on ice. Temperatures were taken at 2 depths on all sides of each pile. Temperatures were taken at 2 depths on all sides of each pile. Samples were sent to Fatih Buyuksonmez, 6259 Progressive Ave Suite 300, San Diego, CA 92154.

Ohio

Arsenic is one of the most common contaminants of concern exceeding risk criteria because soil ingestion is the primary human health risk driver at many urban, military, U.S. Brownfields and CERCLA sites with As-soil contaminated .  Use of contaminant total content instead of bioavailability is often overly conservative and can result in costly and unnecessary soil remedial action. We completed the following two large research projects that determined the ability of in vitro bioaccessible methods to predict relative bioavailable As in contaminated soils. 

Mechanisms and Permanence of Sequestered Pb and As in Soils: Impact on Human Bioavailability. N.T. Basta (PI), Dr. Kirk G. Scheckel, USEPA NRMRL; Dr. Philip M. Jardine, Dr. Chris W. Schadt, Oak Ridge National Laboratory; Dr. Karen Bradham, USEPA NERL; Dr. David J. Thomas, USEPA NHREEL; Dr. Brooke Stevens, OSU; Dr. Richard Hunter Anderson, USAF; Dr. Rufus L. Chaney, USDA ARS.  Strategic Environmental Research and Development Program (SERDP)

Relative Bioavailability of arsenic in soils from mine scarred lands. V.L. Hanley, P. Meyers, California Dept. of Toxic Substances Control (PI); N.T.Basta; S. Casteel, Univ. of Missouri; C. Kim, Chapman Univ., A. Foster, USGS Menlo Park, CA; Dr. Charles Alpers, USGS. U.S. EPA Brownfields Training, Research and Technical Assistance Grant.

Both of these studies were comprehensive evaluations of the ability of different in vitro bioaccessibility (IVBA) methods to predict RBA As. The following conclusions are:

• Total soil As concentration was not correlated with RBA As determined by the adult mouse (r² = 0.24) or the juvenile swine (r² = 0.09) bioassays.
• In general, all of the IVBA methods were predictive of RBA for both the mice and swine bioassays.
• IVBA As from the gastric extraction is a better predictor than IVBA As from the intestinal extraction. Using the GE may also provide more conservative RBA As because the IVBA values are greater for the GE than for the IE (i.e. the As is more soluble) representation a worst case scenario for the estimating As RBA for soil ingestion.
• Recently concluded research has shown California Bioaccessibility (CAB) method is an accurate predictor of swine RBA As for soils with high oxide content and soil As concentrations <1,200 mg As/kg, including soils 1 and 2 for which USEPA Method 1340 and OSU IVG under predicted RBA As.

Our research team developed a new method, the California Bioaccessibility (CAB) method to provide a conservative estimate of RBA As on mining sites soils in California.

Virginia

Xia et al. compared the effects of crop (lettuce or radish), soil amendment type (inorganic fertilizer, raw dairy manure, composted dairy manure, or no amendment), and prior antibiotic use history of manure-derived amendments on the incidence of culturable antibiotic-resistant fecal coliforms in agricultural soils through a controlled field-plot experiment. Antibiotic-resistant culturable fecal coliforms were recoverable from soils across all treatments immediately after application, although persistence throughout the experiment varied by antibiotic class and time. Compost-amended soils had the highest levels of cephalosporin resistant fecal coliforms, regardless of whether the cows from which the manure was derived were administered antibiotics. No statistical differences were observed between soils that grew leafy (lettuce) versus rooted (radish) crops. Only pirlimycin was detectable past amendment application in raw manure amended soils, dissipating 12 to 25% by Day 28. Consequently, no quantifiable correlations between coliform count and antibiotic magnitude could be identified. This study demonstrates that antibiotic-resistant fecal coliforms can become elevated in soils receiving manure-derived amendments.

Xia et al. analyzed antibiotics and abundances of 16S rRNA, sul1, ermB, tet(W) and intI1 genes in the rhizosphere and bulk soils of greenhouse-grown mature lettuce, radish, and broccoli to which raw or composted manure from cattle consuming feed with and without sulfamethazine, chlortetracycline, and tylosin was amended. Loamy sand and silty clay loam soils were used. There was no apparent effect of soil or vegetable type on bulk or rhizosphere antibiotic concentrations. Relative abundances of tet(W) and intI1 in the soils amended with control fertilizer were lower than in those amended with manure or compost (p<0.05), while ermB was not detected in any soils. Composting can reduce initial antibiotic inputs, while the rhizosphere can enhance further dissipation of some antibiotics. Gene markers for antibiotic resistance and mobility remained higher in the compost-amended soils than in chemically-fertilized soils at harvest time.

Xia et al. conducted rainfall simulation to test the surface runoff of four dairy production antibiotics of plots receiving manure via surface application and subsurface injection at different time gaps (day 0, 3, and 7) between manure application and a subsequent rain event. Liquid dairy manure spiked with pirlimycin, tylosin, chlortetracycline, and sulfamerazine was applied to 1.5x2 m test-plots at an agronomic N rate via surface application and subsurface injection. Runoff was a significant route for transporting antibiotics from manure-applied fields, amounting to 0.45-2.62% of their initial input with manure. Subsurface injection reduced sulfamerazine, chlortetracycline, pirlimycin, and tylosin losses in runoff by at least 47, 50, 57, and 88%, respectively. Antibiotic distribution between aqueous and solid phases of runoff was determined by water solubility and partition capacity of antibiotics to soil particles. Manure application three days or longer before a subsequent rain event reduced antibiotic runoff by 9-45 times. Subsurface injection and avoiding manure application within 3 days of rain is recommended.

Xia et al. investigated antibacterial activity of Fe³⁺-saturated montmorillonite using municipal wastewater effluents. Microbial deactivation efficiency was 92±0.64% when a secondary wastewater effluent was mixed with Fe³⁺-saturated montmorillonite for 30 min, and further enhanced to 97±0.61% after 4 hours. This deactivation efficiency was similar to that when the same effluent was UV-disinfected before it exited a wastewater treatment plant. Furthermore, 99.6-99.9% of total coliforms, E. coli, and enterococci in a secondary wastewater effluent was deactivated when the water was exposed to Fe³⁺-saturated montmorillonite for 1 h. Microbial cultural results coupled with the live/dead fluorescent staining assay observation suggested that Fe³⁺-saturated montmorillonite deactivated microorganisms in wastewater through two stages: electrostatic sorption of negatively charged microbial cells to the surfaces of Fe³⁺-saturated montmorillonite, followed by microbial deactivation due to mineral surface-catalyzed microbial cell membrane disruption by the surface sorbed Fe³⁺. Freeze-drying the recycled Fe³⁺-saturated montmorillonite after each usage resulted in 82±0.51% microbial deactivation efficiency even after its fourth consecutive use. This study demonstrated the promising potential of Fe³⁺-saturated montmorillonite to be used in applications from small scale point-of-use drinking water treatment devices to large scale drinking and wastewater treatment facilities.

Xia et al. investigated the transport and distribution of a neonicotinoid (thiamethoxam, TMX) were investigated by growing TMX-coated corn seeds to the V5 growth stage in coarse-textured and fine-textured soil columns (20 and 60 cm lengths). All 20 cm columns leached TMX at levels exceeding the United States Environmental Protection Agency benchmark for aquatic invertebrates (17.5 µg/L). TMX migrated from seeds to adjacent bulk soil by the eighth day and reached deeper soil sections in later growth stages (e.g., 30-45 cm depth by Day 33). Fine-textured soils transported greater than two orders of magnitude more TMX than coarse-textured soils (e.g., 29.9 µg vs 0.17 µg, respectively), which was attributed to elevated evapotranspiration (ET) rates in the sandy soil driving greater net retention of the pesticide and to structural flow occurring in the fine-textured soil. Living plants increased TMX concentrations at depth (i.e., 30-60 cm) compared to the no plant treatment, suggesting that corn growth may drive preferential transport of TMX from coated seeds. Altogether, this study showed that neonicotinoid seed coatings can be mobilized through soil leachate in concentrations considered acutely toxic to aquatic life.

Xia et al. demonstrated that extracellular double-stranded DNA substantially increased the sorption of phenanthrene and pyrene to Na-, Ca-, and Fe-modified montmorillonites. Spectroscopic and computational chemistry analyses confirmed that PAHs were first inserted into DNA by binding with the nucleobases via van der Waals and π−π electron donor−acceptor interactions. Compared to PAHs, the DNA−PAH complex can be more easily sorbed to cation-modified montmorillonites by complexation between DNA phosphate and exchangeable cations in addition to intercalation into clay interlayers. This work highlights the importance of understanding contaminant sorption by many organic compounds that are ubiquitous in soils but not represented by humic and fulvic acids.

Xia et al. investigated the potential for wastewater reuse to disseminate antibiotic resistance genes (ARGs). Samples were collected seasonally in 2014−2015 from four U.S. utilities’ reclaimed and potable water distribution systems before treatment, after treatment, and at five points of use (POU). Shotgun metagenomic sequencing was used to profile the resistome (i.e., full contingent of ARGs) of a subset (n = 38) of samples. Four ARGs (qnrA, blaTEM, vanA, sul1) were quantified by quantitative polymerase chain reaction. Bacterial community composition (via 16S rRNA gene amplicon sequencing), horizontal gene transfer (via quantification of intI1 integrase and plasmid genes), and selection pressure (via detection of metals and antibiotics) were investigated as potential factors governing the presence of ARGs. Certain ARGs were elevated in all (sul1; p ≤ 0.0011) or some (blaTEM, qnrA; p ≤ 0.0145) reclaimed POU samples compared to corresponding potable samples. Bacterial community composition was weakly correlated with ARGs (Adonis, R2 = 0.1424−0.1734) and associations were noted between 193 ARGs and plasmid-associated genes. This study establishes that reclaimed water could convey greater abundances of certain ARGs than potable waters and provides observations regarding factors that likely control ARG occurrence in reclaimed water systems.

Xia et al. tested MetaCompare, a publicly available tool for ranking ‘resistome risk’, which is defined as the potential for antibiotic resistance genes (ARGs) to be associated with mobile genetic elements (MGEs) and mobilize to pathogens. A computational pipeline was developed in which each ARG is evaluated based on relative abundance, mobility, and presence within a pathogen. Previously published metagenomic data derived from distinct aquatic environments were tested. Based on unsupervised machine learning, the test samples clustered in the hazard space in a manner consistent with their origin. The derived scores produced a well-resolved ascending resistome risk ranking of: waste water treatment plant effluent, dairy lagoon and hospital sewage.

Objective 2: Evaluate the range of uses and associated agronomic and environmental benefits/advantages for residuals in agricultural and urban systems.

Specific tasks:

• Evaluate the ability of in situ treatment of contaminated soil with residuals to reduce chemical contaminant bioavailability and toxicity.
• Determine the climate change impacts of organic residuals end use options (i.e., C sequestration, N₂O emissions).
• Quantify sustainability impacts such as water quality (reduced N impairment) and quantity benefits (increased plant available water, increased drought tolerance) and soil quality improvements associated with a range of organic residuals end uses.
• Explore the potential for waste by-products to be used in urban areas including urban agriculture, stormwater infrastructure, green roofs, and in urban green space.
• Evaluate ecosystem services of degraded urban soils amended with residuals.
• Use tools such as life cycle assessment to understand and compare the impacts of a range of residuals end use/disposal options.

Objective 2 Accomplishments:

Arizona

Dr. Ian Pepper and his team are evaluating potential for using Class B biosolids as a cost effective solution for pecan tree deficiencies. Pecan trees are an important specialty crop in Arizona. However, pecan trees are commonly subject to zinc (Zn) deficiencies because of the relatively large demand of the orchards for the micronutrient Zn. One of the major ways to alleviate Zn deficiencies in pecans is foliar application onto the tree canopy. Such foliar applications need to be frequently applied during the growing season. This is particularly true in Arizona where high soil pH values decrease the availability of Zn to the trees since Zn solubility decreases as soil pH increases. A threshold level of leaf Zn of ≃50 µg/g is desirable which can be attained via foliar applications, but there are several problems related to foliar applications. Specifically foliar applications are labor intensive, time consuming, and require purchase of fuel and capital equipment. In addition, they can cause soil compaction due to repeated traffic through the orchard, and can interfere with orchard management such as irrigation.

A second method to eliminate Zn deficiency is soil application of Zn. But in alkaline and calcareous soils, Zn applied to soil reacts with hydroxyl and carbonates resulting in insoluble compounds. Zinc fertilizers such as Zn SO₄ can be applied at 35 kg Zn/Ha, but tend to be ineffective in high pH soils. In contrast, chelated Zn such as Zn-EDTA have been found to elevate leaf Zn levels, but not nut yield or quantity. Additionally, response of pecan to soil Zn application can take several years depending on application rate, form of fertilizer, and method of application. Thus overall, to date, there is no consensus on how to cost-effectively remedy Zn-deficient trees.

In this project we will evaluate a novel potentially cost-effective approach to solving the problem of pecan tree Zn-deficiency; namely the application of Class B biosolids. We believe that biosolids will act as a slow release fertilizer supplying Zn and nitrogen to pecan trees. The solution of a one-time annual application of biosolids eliminates all of the issues associated with foliar Zn applications and traditional inorganic soil fertilizers. An added benefit of the biosolid application is that all essential micronutrients will be more available to pecan trees. Moreover, land application of biosolids is an organic solution to the problem, and the one-time annual application via subsurface soil injection eliminates the issue of any microbial pathogens associated with Class B biosolids. Any pathogen issue is further negated by the fact that pecan harvesting occurs 7-8 months after the springtime annual application, during which any pathogens introduced into the soil would no longer be viable.

In this study, an existing pecan orchard would be utilized such that real-world field data would be collected that would be applicable to all pecan orchards in Arizona. Such quality and quantity increases are likely because biosolid applications could potentially alleviate any micronutrient deficiency that may be unseen and unknown in orchards receiving inorganic fertilizers.

Trees within the pecan orchard have been identified as specific plots. The experiment will consist of three treatments: i) Control plots: no amendment; ii) Plots amended with chelated Zn fertilizer; and iii) Plots amended with Class B biosolids. All treatments are replicated (4 replicates).

Leaf tissue composition will be used to determine the impacts of biosolids application on nutrient uptake. Pecan leaf sample collection protocol requires leaf samples to be collected from the middle of compound leaves in late August. At that time samples will be collected from all plots and analyzed for nutrient content. At harvest time, nut yield will be determined by mechanically harvesting 8 trees/plot. Nut quality will be determined by analysis of a subsample of ≃5 kg of harvested nuts to determine meat yield, percent of good nuts and stick-tight nuts (fruit with shuck remaining stuck to the shell after harvest).

Colorado

Ippolito et al. continued investigating the use of the Soil Management Assessment Framework (SMAF) to ascertain difference in soil quality between biosolids and inorganic N fertilizer applications.  At our North Bennett long-term (20 year) biosolids application site, soils received 0, 2.2, 4.4, 6.7, 9, or 11.2 Mg biosolids ha^-1, or 0, 22, 44, 67, 90, and 112 kg inorganic N ha^-1 in an RCB design with four replicates.  Following wheat harvest in 2016, we analyzed soil from the 0-20cm depth (e.g., zone of incorporation) for the following SMAF indicators:  % clay, % OC, wet aggregate stability, microbial biomass C, potentially mineralizable N, pH, EC, Bd, Olsen-extractable P and K, and beta-glucosidase activity.  All data was entered into the SMAF, with output focused on changes in soil physical, chemical, biological, nutrient, and overall soil quality.  Increasing inorganic N fertilizer rates only improved the nutrient soil quality index.  Increasing biosolids rates improved soil chemical, biological, and overall soil quality indices.  Overall, as compared to N fertilizer, biosolids only improved the biological soil quality index; all other indices were statistically equal.

They began a study focused on aluminum-based water treatment residuals ability to sorb organic P from swine wastewater (containing ~ 7000 mg organic P L^-1), with the hope that organic P sorption is weaker than inorganic P sorption.  This would allow the final product to be potentially used as a P fertilizer source.  They found that 99.9% of organic P was sorbed within 1 day, and that the Al-WTR composite can potentially release 380 to 485 mg total P kg^-1.

Florida

An intended, long-term, well-instrumented field study was established by Silveira et al. to evaluate various agronomic and environmental impacts of biosolids applied to pastures in south Florida. Land application of Class B biosolids to pasture land is common in Florida and well received by ranchers, but remains a practice that concerns some. Environmental concerns and the need (or lack thereof) for legislation to protect against environmental impacts with respect to water quality are the major focus of the project. The experiment is designed to evaluate the effects of various locally available biosolids alone, and in combination with a locally available biochar, on forage, soil, and water quality, and on greenhouse emissions. Efforts to attract continuing research funds to support the field effort for a minimum of 3 more years have been frustrating. Support to date has been from special, annual legislative allotments to the Florida Cattlemen’s Association and “fiscal year-end” funding from the FL AES. Funding has been modest and frequently delayed and often no-congruent with needs. Continued and adequate future support is tenuous, but work continues, including rainfall simulations to assess biosolids properties on P losses to water bodies.

Hawaii

Biochar, a product of biomass that is heated in an oxygen limited environment (pyrolysis), has been reported to improve soil quality and increase plant growth. To quantify and further characterize such effects of biochar, three experiments were conducted by Hue et al.: (1) a greenhouse trial on an acidic tropical Ultisol, which evaluated the aluminum (Al) detoxifying potential of biochar, using Desmodium intortum, an Al sensitive forage legume as the test plant; (2) a greenhouse trial using nitrogen (N) fertilizer sources, both organic and synthetic, with and without biochar, which measured the capacity of biochar to regulate/release N to Chinese cabbage (Brassica rapa Chinenesis group) growth; and (3) a field trial on a highly weathered Oxisol, which documented the long-term, field-condition effects of biochar on a variety of crops [sweet corn (Zea mays), okra (Abelmoschus esculentus), and soybean (Glycine max)]. Our results show: (1) At an application rate of 2.5% (approximately 25 tons/ha), a kiawe-wood biochar could reduce Al toxicity and increase D. intortum growth as much as lime (CaCO₃) applied at 3 cmolc/kg (1.5 tons/ha). CaCO₃ equivalent (represented by ash content) and COOH, OH functional groups on the biochar surface were likely responsible for these effects. (2) At a same total N rate of 200 mg/kg, cabbage yield was much higher in the presence of a wood-based biochar (at 2%) than when urea or organic N fertilizer was applied alone, and yield increased became even more pronounced in the second harvest than in the first. This increased N use efficiency could be attributed to biochar properties, such as large surface area and numerous tiny pores. (3)  Under field conditions, corn yield ( first season) was nearly doubled in the presence of 2% biochar (derived from macadamia shells) when N was applied as urea or blood meal (10% total N) at 150 or 300 kg N/ha rate. Interestingly, the effect of biochar on plant growth seemed to extend beyond N nutrition because the treatments receiving biochar but no N input also out-yielded those having N input but no biochar. The prolonged/aging effect of biochar will be further studied in future time.

Kansas

A new field study, to investigate potential for using residual (class B biosloids) amendment at contaminated military sites, was initiated in summer 2016 by Kansas State University researchers (Hettiarachchi et al.). This will be continued at least for three years and the main objective is to find ways to utilize unused land/sites to grow second generation biofuel crops while maintaining or improving soil quality, and keeping soil contaminants in place. Results so far shows that tilling and soil treatment additions have increased the dry matter yield. Soil analysis for various parameters including bioaccessible lead and plant tissue analysis for lead and nutrients are underway.

Plant systems have a significant capacity to remediate marginal waters through several phytoremediation processes including uptake (e.g., nutrients, trace elements), accumulation (e.g. salts), and assist with biotransformation of inorganic compounds (e.g., nutrients, trace elements). Salicornia could be a suitable halophilic plant to capitalize on its salt-tolerance potential for treating marginal waters. A greenhouse study was initiated to determine ability of Salicornia europaea to grow in flue gas desulfurization (FGD) wastewater, which is high in salts and selenium (Se); or brackish waters. We continued this work in 2017.

Minnesota

The Metropolitan Council in the Twin Cities have funded Rosen et al. to conduct an incubation and three-year field study of sewage sludge incinerator ash as a phosphorus fertilizer.  The study will compare this ash to conventional P fertilizer, biosolids, and struvite.  They will be looking at the soil chemical characteristics with respect to phosphorus release and metals concentrations, plant yield and chemical composition (P and metals), and potential changes in microbial community diversity and abundance.  The first year of the field study is underway in Rosemount, MN where 160 plots of corn are set up with the 4 fertilizers at 5 rates (0x, 0.5x, 1x, 1.5x).  The incubation is intended to describe phosphorus release and microbial changes from the ash in a controlled setting and will be done in summer 2018.

In 2017, Rosen et al. began the first year of a three-year field study to study the effects of phosphorus-based sewage sludge byproducts on soil, microbial, and plant analyses. Plant grain and biomass results at harvest showed a very successful grain yield overall. All plots had high grain yields with no significant response due to source or rate. Similarly, end-of-season stover (biomass and husk) did not show a significant response to source or rate. Anecdotally, phosphorus studies often take a year or two to deplete existing soil phosphorus and thus, see the full effects of treatment. Chemical analysis of plant material (grain, stover, and husk) are still being run.

Soil analysis results overall showed minimal differences between fertilizer types as most differences were due to application rates. Olsen-P and Bray-P concentrations increased with increasing application rate for all sources but not there were no significant differences between fertilizer types. DTPA-zinc, DTPA-copper, and exchangeable sodium also increased significantly with application rate and had highly significant effects in biosolids and ash applications. Otherwise, neither source nor rate had significant impacts on other available or total elements. Due to the higher concentrations of certain elements in biosolids and ash and the resulting effects seen in the 2017 field season, they will continue to closely monitor these concentrations in coming field seasons.

In-situ Plant Root Simulator ® (PRS) probes showed a significant response in phosphorus levels based on source and rate. Specifically, late season phosphorus increases with increasing rate and is highest in struvite- and biosolids-treated plots. PRS probes were buried for 3-4 weeks and used to estimate the plant available phosphorus levels in the soil. PRS probes are anion and cation resins, which after burial, come into equilibrium with water in the soil and represent the phosphorus available for immediate uptake.

Rosen et al. evaluated potential benefits of an organic fertilizer containing coffee chaff for greenhouse and garden plants.

JavaCycle (4-4-4) is a coffee-chaff-based organic fertilizer with potential for use in gardens and potted plants. A previous comparison of JavaCycle with the established organic fertilizer Garden-tone (Espoma; 3-4-4) did not utilize similar application rates of the two products, and a more systematic comparison was therefore desirable. They evaluated two JavaCycle formulations, Java 10 (10% chaff) and Java 40 (40% chaff), in comparison to Plant-tone (Espoma; 5-3-3) as nutrient sources for Valmaine lettuce and Celebrity tomatoes grown in the greenhouse in one-gallon and three-gallon containers, respectively. Ten treatments were applied, including an unfertilized control and each of the three fertilizers applied at 0.5 1.0, and 1.5 times the recommended application rate of Plant-tone. An experiment was conducted with Valmaine lettuce with the application rates of the JavaCycle products set to match the application rate of N provided by Plant-tone at each of the three fertilizer application rates. The 1.0X and 1.5X rates of both JavaCycle products were found to be detrimental to seed germination and plant yield and health. Therefore, a second lettuce experiment, as well as the tomato experiment, were conducted with the fertilizer application rates matched volume-for-volume.

The responses of lettuce plants to treatment, fertilizer type, application rate, and the interaction between fertilizer type and application rate were measured in terms of germination, yield, leaves produced over time, soil pH and salt and nutrient concentrations, and leaf nutrient concentrations. The responses of tomato plants were measured in terms of fruit yield and quality, plant height over time, total shoot dry biomass (minus fruits) produced over the season, soil pH and salt and nutrient concentrations, and leaf nutrient concentrations. Lettuce yield was highest at the 1.0X application rate and was not affected by the fertilizer source applied. Lettuce leaf count at harvest was lower at the 1.5X rate than at the two lower rates and was not affected by the fertilizer applied. Soil pH was lower at the 0.5X rate than at the higher two rates, and the ratio of soil NH₄-N to NO₃-N was high in all treatments, suggesting that the soil nitrification rate was low. Lettuce plants grown with Plant-tone had higher soil and tissue concentrations of Zn, Mn, Cu, and B than those grown with either JavaCycle product. Tomato yield was higher, while the prevalence of blossom end rot and yellow shoulders were lower, at higher application rates. Tomato sugar content was not affected by application rate, and no measure of tomato yield or quality was related to the fertilizer used. Tomato plant height was lower in treatments receiving the 0.5X rate than in those receiving the higher two rates, and shoot biomass was higher at higher fertilizer application rates, but neither variable was related to the fertilizer applied. Tomato plants grown with Plant-tone had higher soil and tissue concentrations of N, P, Zn, Cu, and B than those grown with either JavaCycle product.

Overall, they found that JavaCycle was an effective fertilizer for container-grown lettuce and tomatoes, similar to Plant-tone. Even though the potting mix contained dolomitic lime, we noted that lettuce plants grown with any of the three fertilizers tested often exhibited tip burn, while many tomato fruits had blossom end rot or yellow shoulders. All of these syndromes are consistent with calcium deficiency, and it may be advisable for growers to apply a more soluble calcium fertilizer such as gypsum in addition to JavaCycle when growing plants in a peat-based potting medium.

New Mexico

Alfalfa (cv. 6829R) was planted August 18, 2017, by researchers at Agricultural Science Center at Tucumcari, New Mexico State University, in an area of Redona fine sandy loam, which was conventionally tilled and formed into a flat seedbed for sprinkler irrigation with canal water on the southeast side and treated municipal wastewater on the southwest side. Plots (5 ft x 20 ft) were sown using a disk drill fitted with a seed-metering cone at 20 lb inoculated seed/A in a strip-plot design with 4 replications within each irrigation source area. The effective planting width was 4 ft (8, 6-inch rows). In 2017, irrigations totaling 1.5 inches were applied in August and September to supplement 12.8 inches of growing season precipitation (August through October 2017). In early October, the irrigation system failed and no further irrigation was applied in 2017, while after the first week in October, precipitation totaled 0.04 inches for the remainder of the year. No fertilizers or pesticides were applied in 2017.

Soil samples had been collected immediately pre-planting from each strip test for fertility and soil microbial community by phospholipid fatty acid (PLFA) analyses. On August 29 and September 6, 2017, plant counts were taken and averaged. On October 25, 2017, all plants in 1 ft of all rows (4 ft²) from the east end of each plot were hand-clipped to ground level, weighed, dried at 140°F for 48 hours, and reweighed for calculation of dry matter percentage and dry weight prior to being delivered to the lab for NIRS analysis of nutritive value. There were 6-22 leaves on harvested plants suggesting a degree of variation over time in germination and/or emergence of the alfalfa in this study.

Plant count, seedling dry wt., and selected nutritive value and selected PLFA data were analyzed using SAS PROC MIXED procedures to determine where differences (P < 0.05) existed between water sources. Replicate within water source was considered random.

There was no difference due to irrigation source in the number of plants/m²; however, dry weight/m² and dry matter percentage were both higher for alfalfa irrigated for establishment using canal water compared to treated wastewater. Greater dry weight may have been due to more rapid germination allowing for more mature plants at the time of sampling. This also would explain the greater acid detergent fiber (ADF), neutral detergent fiber (NDF), and NDF digestibility (NDFD) for alfalfa irrigated with canal water compared to alfalfa irrigated with wastewater as more mature plants will have greater fiber accumulation and a decrease in the digestibility of the fiber.

Preplant soil analysis revealed no apparent issues in regard to fertility (including toxicities) or potential salt problems. Total microbial biomass and diversity index in the soil were not different between water sources after establishment; however, there was a difference in the proportion of total microbial biomass being arbuscular mycorrhizae. The total biomass was poor and slightly below average for canal water irrigated soil and wastewater irrigated soil, respectively, and the diversity index was average and slightly below average for the canal water irrigated soil and the wastewater irrigated soil, respectively. The lack of arbuscular mycorrhizae in the wastewater area may indicate that compounds of concern in the wastewater have an impact on these soil microbes. Lack of precipitation or irrigation from early October until sampling time also may have been a factor.

Rhizobia were not detected in the PLFA samples, although, the alfalfa roots included in the soil sample were nodulated. Perhaps the lack of detectable Rhizobium was because nodules had not been shed to release nitrogen into the soil, which also would have released the Rhizobium.

In 2018, the center 5 ft x 15 ft of each plot will be harvested 6 times for yield using a self-propelled forage plot harvester equipped with a weighing system. For each harvest, a subsample of harvested material from each plot will be collected and dried to determine dry matter concentration and yield as well as for nutritive value analysis by near-infrared spectroscopy. Samples for PLFA analysis also may be collected in spring and fall. A second study also will be planted either in spring or late summer.

Municipalities are seeking uses for treated wastewater to minimize the release of potential pollutants into surface and ground water bodies. Because the soil can be a natural filtering agent, agricultural irrigation is being considered. Wastewater treatment plants (WWTP) are producing water that is generally safe to apply to animal feed and fiber crops. Alfalfa is the most important forage crop worldwide because it is adapted to a wide range of soil and climatic factors and has been successfully established and grown New Mexico State University’s Agricultural Science Center using recycled Class 1B treated municipal wastewater from the City of Tucumcari WWTP. However, yield reductions have been observed compared to previous years when only canal water was available. The Agricultural Science Center has the capability to apply both treated wastewater and canal water through the same irrigation system in the same field, which has a fairly uniform soil type. Determination of the potential impact of using treated municipal wastewater for irrigating alfalfa could assist producers with deciding whether or not to use the water source to irrigate alfalfa.

Pennsylvania

A study was conducted by researchers at Pennsylvania State University to identify the source of anomalously high copper (Cu) in Penn State’s biosolids. All other regulated trace elements are low, but the Cu level sometimes exceeds 1500 mg/kg, precluding land based recycling as an exceptional quality (EQ) material according to federal regulations. The source of Cu was determined to be heat exchangers where steam impacts Cu tube bundles. The condensate is softened prior to reuse and Cu-rich reject stream is sewer disposed. A process was designed to remove Cu via precipitation and settling prior to discharge.

Assessing stress in plants directly, rather than estimating stress conditions based on soil data, is an ongoing challenge and one that is important to meet as land-based recycling of effluent increases in both humid and arid regions. Both leaf capacitance and leaf thickness measurements were determined using sensors developed. Results were published in appropriate engineering journals. A patent was applied for and discussions were held with potential patent purchasers.

Additional collection of soil samples occurred in this past year. Extractions were completed and analyses are being conducted. Soil samples were also prepared for analysis for antibiotic resistance development. Initial data indicates an enhancement in antibiotic resistance in soils irrigated with effluent, when compared with non-irrigated soils.

Miscanthus biomass production on mined land and response to nutrient application as inorganic fertilizer or as spent mushroom compost (SMC) is being investigated in a multi-year experiment. Biomass production has increased in each of the first three years since establishment and yield was increased by nutrient addition. In year three the yield response to nutrient addition as SMC was greater than to comparable amounts inorganic fertilizer. While there were some periods when soil N availability was greater with SMC addition than with fertilizer, the difference was not consistent through the growing season and miscanthus N uptake did not differ between nutrient sources.

Virginia

Badgley et al. found that increased amounts of organic carbon and inorganic nitrogen in experimental bioretention systems amended with compost increased denitrification and increase the proportion of nitrogen that could be removed from artificial stormwater bioretention mesocosms. Further research is necessary to determine the balance between increased performance and increased leaching of nutrients from bioretention cell components. Preliminary results from field measurements of bioretention systems suggest that increased amounts of organic residuals in soil media can favor complete denitrification and reduce the amount of nitrous oxide emissions.

Daniels et al. Long-term effects (30+ years) of biosolids application (0, 56, 112 and 224 Mg/ha; n = 4 each) on reclaimed Appalachian hard rock coal mine spoils were evaluated by Daniels et al. via observation of changes in morphology and chemical/physical properties. Analysis of field morphological results indicates that application of the higher rates of biosolids (112 and 224 Mg/ha) were still apparent after 24 years by surface horizons having darker, thicker, and better aggregated characteristics. Physical and chemical analyses showed higher total C, N and P levels in the 112 and 224 Mg biosolids/ha than in the inorganically fertilized only and 56 Mg biosolids/ha treatments.

Long-term (10 to 15 year) effects of woody waste compost additions on soil and vegetation properties in created forested wetlands continued to be evaluated in 2017 by Daniels et al. in two replicated (n = 4) experiments in eastern Virginia. Loading rates at one experiment varied from 56 to 330 Mg/ha (dry) and were incorporated into truncated plastic and clayey subsoil materials. The loading rate at the second site was 75 Mg/ha and the compost was incorporated into coarse sandy dredge materials and compared with local topsoil return (15 cm) vs. no amendment. Combined results from the two experiments indicate that optimal compost addition rates are approximately 75 to 224 Mg/ha, depending on long-term management goals. If the goal is development of appropriate (low) soil redox conditions, then lower rates are adequate. However, meeting certain regulatory goals (e.g., 5% organic matter in surface A horizons) may require the higher loading rates, and the users must understand the difficulty of incorporating compost additions at those higher rates. Compost additions clearly aided initial establishment and long-term growth of herbaceous and woody vegetation (Betula nigra and Quercus palustris) at the loading rate experimental site, but had no net effect at the second experiment when compared with topsoil return. However, installation of microtopographic variability (e.g. pits and mounds) had very strong effects on tree growth (Taxodium distichum) at this sandy site.

Ervin and Evanylo continued to compare the effects of annual exceptional quality (EQ) biosolids products and inorganic fertilizer on rehabilitation of disturbed urban soil for the establishment and production of cool season turfgrass. Biosolids products performed better than the inorganic fertilizer during the trial period. Clipping yield, normalized difference vegetative index (NDVI), turfgrass quality rating and soil bulk density, were significantly improved by biosolids products applied at the agronomic nitrogen rate than the biosolids applied at the phosphorus rate and the inorganic fertilizer (p-value <0.05). Turfgrass growth and quality and soil bulk density were improved with Biosolids products that supplied the most carbon regardless of total plant available N rate.

Evanylo et al. compared the effects of exceptional quality (EQ) biosolids products at varying rates and inorganic fertilizer applied to a manufactured urban soil comprised of clayey subsoil fill from two construction sites on vegetable crop yields, soil properties and leachate quality. Fall vegetable crop yields were higher with 5x than 1x plant available N (PAN) application rates, but summer vegetable yields were higher with 1x PAN applied in the spring than (following a fall 1xPAN rate) than only a fall 5x PAN rate. Leachate nitrate mass loss to lysimeters was not significantly different among seasonal (fall and spring) 1x PAN amendment application and fall 5x PAN amendment application. Soil test phosphorus was only slightly increased despite amendment P rate that supplied 10x P needs due to high P binding capacity of the calcareous subsoil clay and the high concentrations of P-binding Fe in the biosolids amendments. Little difference in crop yield, soil properties, or leachate quality occurred among the EQ biosolids products, i.e., biosolids+shredded woody mulch, composted Biosolids, and air-dried biosolids.

Washington

Dr Brown has continued work on use of soil based methods to predict phosphorus availability for storm water bioretention systems. An MS student, Julia Jay, tested a wide range of bioretention soil mixtures including mixes with different rates of biosolids compost, different types of compost and different additives (WTRs, oyster shells, sawdust) for efficacy at controlling P release from storm water.  Both synthetic and actual storm water were including in this study.  Phosphorus release was best predicted using the phosphorus saturation ratio.  In addition to P movement, nitrogen, metals and PAHs were also measured.

Dr. Brow

Journal Articles

Afzal, A., S. Duiker, and J. Watson. 2017. Leaf thickness to predict plant water status. Biosystems Engineering 156:148-156.

Afzal, A., S. Duiker, S., J. Watson, J. and D. Luthe. 2017. Leaf thickness and electrical capacitance as measures of plant water status. Transactions of the ASABE 60 (40), 1063 – 1074.

Attanayake, C.P., G.M. Hettiarachchi, Q. Ma, G.M. Pierzynski, M.D. Ransom. 2017. Lead speciation and in vitro bioaccessibility of compost-amended urban garden soils. J. Environ. Qual. 46:1215-1224 doi:10.2134/jeq2017.02.0065

Barbarick, K.A., J.A. Ippolito, and J. McDaniel. 2017. Meta-analysis of biosolids effect in dryland wheat agroecosystems. J. Environ. Qual. 46:452-460.

Chen, C. Q., and K. Xia. 2017. Fate of Land Applied Emerging Organic Contaminants in Waste Materials. Curr. Pollution Rep. 3:38-54.

Cimo, G., A. Haller, K. Spokas, J. Novak, J. Ippolito, and C. Kammann. 2017. Mechanisms of nitrate capture in biochar: Are they related to biochar properties, post-treatment and soil environment? European Geosciences Union. April 22-29. Vienna, Austria.

Clark, E. V., C. Zipper, W. L. Daniels, Z. W. Orndorff, and M. J. Keefe. 2017. Modeling Patterns of Total Dissolved Solids Release from Central Appalachia, USA Mine Spoils. Journal of Environmental Quality, 2017(46), 55-63. doi:10.2134/jeq2016.04.0149

D’Angelo, E. M. 2017. Sorption-desorption equilibrium and diffusion of tetracycline in poultry litters and municipal biosolid soil amendments. Chemosphere 188:494-501.

Ippolito, J.A., C.M. Berry, D.G. Strawn, J.M. Novak, J. Levine, and A. Harley. 2017. Biochars reduce mine land soil bioavailable metals. J. Environ. Qual. 46:411-419.

Fiedler, S., T. Fuertes-Mendizábal, J.M. Estavillo, J.A. Ippolito, N. Borchard, M.L. Cayuela, K. Spokas, J. Novak, C. Kammann, and N. Wrage-Mönnig. 2017. Influence of 13 different biochars on N₂O production and its sources during rewetting-drying cycles. European Geosciences Union. April 22-29. Vienna, Austria.

Galkaduwa, M.B., G.M. Hettiarachchi, G.J. Kluitenberg, S.L. Hutchinson, L. Erickson, L. Davis. 2017. Transport and transformation of selenium and other constituents of flue-gas desulfurization wastewater in water-saturated soil materials. J Environ Qual. 46(2):384-392. doi: 10.2134/jeq2016.09.0335.

Gangaiah C., Ahmad A., Hue N., Wang K, Radovich T. 2017. Evaluating three invasive algal species as local organic source of potassium for pak choi (Brassica rapa, Chinensis group) growth. HortScience 52(3):436-440.

Ippolito, J.A., C. Kammann, M. Schirrmann, N. Wrage-Mönnig, T. Estavillo, T. Fuertes, M. Cayuela, N. Borchard, J. Novak, K. Spokas, and G. Sigua. 2017. Biochar mediated mechanisms for reducing N₂O emissions: An overview. European Geosciences Union. April 22-29. Vienna, Austria.

Jay, J.G., S.L. Brown, K. Kurtz and F. Grothkopp. 2017.  Predictors of phosphorus leaching from bioretention soil media.  J. Environ. Qual. 46:1098-1105

Kammann, C., N. Borchard, M. Cayuela, N. Hagemann, J. Ippolito, S. Jeffery, J. Kern, D. Rasse, S. Sanna, H-P. Schmidt, K. Spokas, and N. Wrage-Mönnig. 2017. Biochar as a tool to reduce the agricultural greenhouse burden – Knowns, unknowns and future research needs. J. Environ. Engineer. Landscape Management. 25:114-139.

Laidlaw, M.A.S., G.M. Filippelli, S. Brown, J. Paz-Ferreiro, S.M. Reichman, P. Netherway, A. Truskewzcz, A.S. Ball, H.W. Mielke.  2017.  Case studies and evidence-based approaches to addressing urban soil lead contamination.  Applied Geochemistry http://doi.org/10.1016/j.apgeochem.2017.02.015

Laird, D.A., J.M. Novak, H.P. Collins, J.A. Ippolito, D.L. Karlen, R.D. Lentz, K.R. Sistani, K. Spokas, and R.S. Van Pelt. 2017. Multi-year and multi-location soil quality and crop biomass yield responses to hardwood fast pyrolysis biochar. Geoderma. 289:46-53.

Mehmood, K., E. Chávez Garcia, M. Schirrmann, B. Ladd, C. Kammann, N. Wrage-Mönnig, C. Siebe, J.M. Estavillo, T. Fuertes, M. Cayuela, G. Sigua, K. Spokas, A.L. Cowie, J. Novak, J.A. Ippolito, and N. Borchard. 2017. Biochar research activities and their relation to development and environmental quality. A meta-analysis. Agron. Sustain. Dev. 37:22.

Morris, J., S.L. Brown, M. Cotton and H. Scott Matthews. 2017. LCA harmonization and soil science rankings results on food waste management methods.  Environ. Sci. Tech. 10.1021/acs.est.6b06115

Obrycki, John F., Darryl B. Hood, Tyler Serafini, Chris Alexander, Pam Blais, Nicholas T. Basta. Public health data contextualizes soil Pb hazard management in Ohio. 2017. Journal of Public Health Management and Practice. doi: 10.1097/PHH.0000000000000488

Obrycki, John F, Nicholas T. Basta, Robyn S. Wilson. 2017. Evaluating public and regulatory acceptance for urban soil management approaches. J. Environ. Qual. 46: 20-26. doi:10.2134/jeq2016.06.0230.

Obrycki, John F, Kirk G. Scheckel, and Nicholas T. Basta. 2017. Soil solution interactions may limit Pb remediation using P amendments in an urban soil. Environ Pollut. 220:549-556.

Paredez, J. M, N. Mladenov, M. B. Galkaduwa, G.M. Hettiarachchi, G.J. Kluitenberg, S.L. Hutchinson. 2017. A soil column study to evaluate treatment of trace elements from saline industrial wastewater. Journal of Water Science and Technology. Available Online 31 July 2017, wst2017413; doi: 10.2166/wst.2017.413

Pepper, I.L., Brooks, J.P. and Gerba, C.P. Antibiotic resistant bacteria in municipal wastes: is there reason for concern? Environ. Sci. & Technol. 52:3949-3959.

Pepper, I.L., and Gerba, C.P. 2018. Risk of infection from Legionella associated with spray irrigation of reclaimed water. Wat. Res. 139:101-107.

Qin, C., C. Q., Chen, C. Shang, and K. Xia. 2017. Fe³⁺-Saturated Montmorillonite Effectively Deactivates Microorganisms in Wastewater. Sci. Total Environ. 622-623:88-95.

Radolinski, J., J. X. Wu, K. Xia, and R. Stewart. 2017. Transport of a Neonicotinoid Pesticide, Thiamethoxam, from Artificial Seed Coatings. Sci. Total Environ. 618:561-568.

Ray, P, C.Q. Chen, K. F. Knowlton, A. Pruden, and K. Xia. 2017. Fate and effect of antibiotics in beef and dairy manure during static and turned composting. J. Environ. Qual. 46:45-54.

Sassi, H.P., Ikner,L.A., Abd-Elmaksoud, S., et al. 2018. Comparative survival of viruses during thermophilic and mesophilic anaerobic digestion. Sci. Tot. Environ. 615:15-19.

Sassi, H.P., Reynolds, K.A., Pepper, I.L., et. al. 2018. Evaluation of hospital-grade disinfectants on viral deposition on surfaces after toilet flushing. Am. J. Infect. Cont. 46:507-511.

Schmitz, B.W., Morizama, H., Eliji, H., et. al. 2018. Reduction of Cryptosporidium, Giardia, and fecal indicators by Bardenpho wastewater treatment. Environ. Sci. & Technol. 52:7015-7023.

Sendagi, S.M. and H.A. Elliott. 2017. Atmospheric nitrogen loss factor (f) used in determining nitrogen-based municipal wastewater effluent irrigation rates: Design and nitrogen-balance estimated F values. Nutr. Cycl. Agroecosyst. 109:181-191.

Spokas, K.A, R. Weis, G. Feyereisen, D.W. Watts, J.M. Novak, T.J. Lee, and J.A. Ippolito. 2017. Biomass or biochar – Which is better at improving soil hydraulic properties? Acta Horticulturae. 1146.31:235-242.

Vega, M. A., H. V. Kulkarni, N. Mladenov, K. Johannesson, G. M. Hettiarachchi, P. Bhattacharya, N. Kumar, J. Weeks, M. Galkaduwa and S. Datta. 2017. Biogeochemical Controls on the Release and Accumulation of Mn and As in Shallow Aquifers, West Bengal, India. Front. Environ. Sci., 23 June 2017. doi.org/10.3389/fenvs.2017.00029.

Whitacre, Shane D., Nicholas T. Basta, Brooke N.  Stevens, Valerie Hanley, Richard H.  Anderson, and Kirk G. Scheckel. 2017. Modification of an Existing In vitro Method to Predict Relative Bioavailable Arsenic in Soils. Chemosphere 180:545-552.

Zohar, I., Litaor, M.I., J.A. Ippolito, and M. Massey. 2017. Innovative approach for agro-wastewater phosphorus removal using water treatment residuals. Chemosphere. 168:234-243.

Presentations/Abstracts

Ayers, B., K. Elkin, F. Kibuye, H.E. Gall. 2017. Pharmaceuticals at Penn State’s Living Filter: from wastewater to groundwater. ASABE Paper No. 1700255. St. Joseph, MI.: ASABE.

Badgley B. D., Waller L. J., Evanylo G., Krometis L. A. H., Strickland M. S., and Wynn-Thompson T. (2017). Comparing engineered and environmental controls of microbial denitrification in mature bioretention cells. UNC Water Microbiology Conference, Chapel Hill, NC, USA. May 15-17.

Bordi, K., J. Ippolito, J McDaniel, and K. Barbarick. 2017. Biosolids Land Application and Phosphorus: A Simple Runoff Study. American Society of Agronomy Meetings. October 22-25. Tampa. FL.

Chen, C. Q., G. Guron, K. Xia, A. Pruden, M. Ponder, and P. Du. Antibiotics and antibiotic-resistant genes in bulk and rhizosphere soils: A greenhouse study of vegetables grown in soils amended with antibiotic-containing manure. 254^th American Chemical Society National Meeting. Washington D.C., August 20-24, 2017.

Chen, C. Q., and K. Xia. Effect of earthworm activity on the fate of antibiotics and abundance of antibiotic-resistant bacteria and resistance genes in a compost amended silt loam soil. 254^th American Chemical Society National Meeting. Washington D.C., August 20-24, 2017

Daniels, W. L., Whittecar, G. R., Thompson, T., Agioutantis, Z., & Stone, S. (2017). Mine Reclamation Applications of a New Water Budget Model: Wetbud. In J. G. Skousen, & L. M. McDonald (Eds.), Abstracts, 34th Annual Meeting of the ASMR, April 9-13, 2017, Morgantown, West Virginia. Morgantantown, WV. Retrieved from http://www.asmr.us/Meetings/Past-Meetings?y=2017#Content

Daniels, W. L., & S. Carpenter. 2017. Development of International Standards for Mine Reclamation. In J. G. Skousen, & L. M. McDonald (Eds.), Abstracts, 34th Annual Meeting of the ASMR, April 9-13, 2017, Morgantown, West Virginia. Morgantown, WV: ASMR. Retrieved from http://www.asmr.us/Meetings/Past-Meetings?y=2017#Content

Davis L. C., Alasmary Z., Erickson L. E., Hettiarachchi G., Nurzanova A., Pidlisnyuk V., Roozeboom K., Stefanovska T., Trogl J. Using a second generation biofuel crop for phytostabilization of contaminated military lands. 17 Annual Meeting of the American Ecological Engineering Society, "Ecological engineering for adaptation in the Anthropocene", May 23-25, 2017, UGA, Athens, Georgia.

Erickson L., Pidlisnyuk V., Trögl J., Shapoval P., Popelka J., Davis L., Stefanovska T., Hettiarachchi G. Perennial phytotechnology with biomass production for abandoned military site in Sliač, Slovakia. International conference on Chemical technology and engineering, Lviv, Ukraine, June 26-30, 2017.

Fuertes-Mendizábal, T., X. Huérfano, S. Menéndez, C. González-Murua, M.B. González-Moro, J.A. Ippolito, C. Kammann, N. Wrage-Mönnig, N. Borchard, M.L. Cayuela, K. Spokas, J. Novak, and J.M. Estavillo. 2017. Biochar reduces the efficiency of the nitrification inhibitor 3,4-dymethylpyrazole phospate (DMPP) mitigating N₂O emissions. European Geosciences Union. April 22-29. Vienna, Austria.

Hettiarachchi, G.M. Z. Almasary, K. L. Roozeboom, L.C. Davis,  L.E. Erickson, V. Pidlisnyuk, T. Stefanovska, A. Nurzanova, and J. Trogl. 2017. Field-based investigations on phytostabilization of a contaminated military site using biofuel crop growth assisted with soil amendments. International Phytotechnolgy Conference, Sep. 2017, Montreal, Canada.

Hettiarachchi, G.M., M.B. Galkaduwa, G. Kluitenberg, and S. Hutchinson. 2017. Poorly crystalline iron oxide minimize arsenic mobility in a water-saturated soil column system designed for FGD wastewater treatment. International Conference on Biogeochemistry of Trace elements. July 2017, Zurich, Switzerland.

Hue N. 2017. Arsenic reactions and remediation in tropical soils. 2017. The 3^rd. Intern. Conf. on Environmental Pollution, Restoration, and Management. Quy Nhon, Vietnam. March 5-9, 2017.

Ippolito, J.A., C.M. Berry, D.G. Strawn, J.M. Novak, J. Levine, and A. Harley. 2017. Heavy metal sorption mechanisms in biochar amended mine tailings. 14^th International Conference on the Biogeochemistry of Trace Elements. Zurich,        Switzerland. July 16-20.

Ippolito, J.A., and K.A. Barbarick. Measuring and predicting trace element speciation in long-term biosolids-amended soils. 14^th International Conference on the Biogeochemistry of Trace Elements. Zurich, Switzerland. July 16-20.

Ippolito, J.A. 2017. Soil nutrients and cycling: The big 3 and availability issues in calcareous soils. Urban and Small Farms Conference. February 22-23. Salt Lake City, Utah.

Johnson, D. K., Daniels, W. L., & Zipper, C. E. (2017). Field Predictors for TDS Generation Potential from Appalachian Mine Spoils. In J. G. Skousen, & L. M. McDonald (Eds.), Abstracts, 34th Annual Meeting of the ASMR, April 9-13, 2017, Morgantown, West Virginia. Morgantown, WV. Retrieved from http://www.asmr.us/Meetings/Past-Meetings?y=2017#Content

Kammann, C., A. Haller, H-P. Schmidt, N. Wrage-Moennig, J.A. Ippolito, T. Fuertes-Mendizabal, J.M. Estavillo, N. Borchard, M. Cayuela, K.A. Spokas, J.M. Novak. 2017. Biochar as a tool for nitrogen management: Increasing benefits while reducing environmental burdens. American Society of Agronomy Meetings. October 22-25. Tampa. FL.

Le, H., R. O. Maguire, and K. Xia. 2016. Effects of manure land application technologies and timing on environmental fate of four antibiotics commonly used in dairy production. ASA-CSSA-SSSA International Annual Meetings, Phoenix, AZ, Nov. 6-9.

Ma, P. and C. J. Rosen. 2017. Phosphorus Release from Sewage Sludge Incinerator Ash. Soil Science Society of America annual meeting, Tampa, FL. https://scisoc.confex.com/crops/2017am/webprogram/Paper108966.html

Novak, J.M., J. Ippolito, K. Spokas, G. Sigua, C. Kammann, N. Wrage-Mönnig, N. Borchard, M. Schirrmann, J.M. Estavillo, T. Fuertes, S. Menendez, and M.L. Cayuela. 2017. Crafting biochars to reduce N₂O and CO₂ emissions while also improving soil quality. European Geosciences Union. April 22-29. Vienna, Austria.

Novak, J.M., M.G. Johnson, J.A. Ippolito, G.C. Sigua, K.A. Spokas, K.M. Trippe, and T.F. Ducey. 2017. Biochars ability to sequester metals in contaminated mine spoils: A greenhouse study. European Geosciences Union. April 22-29. Vienna, Austria.

Novak, J.M., M.G. Johnson, J.A. Ippolito, T.F. Ducey, G.C. Sigua, D.W. Watts, and K.A. Sigua, G.C., J.M. Novak, M.G. Johnson, K. Spokas, J.A. Ippolito, T. Ducey, and K. Trippe. 2017. Efficacy of designer biochars with or without lime application for remediating heavy metals in mine spoil soils. European Geosciences Union. April 22-29. Vienna, Austria.

Pepper, I.L. 2017. Anammox for sidestream treatment of wastewater effluent. 22^nd European Biosolids and Organic Resources Conference, Leeds UK.

Pepper, I.L. 2017. Fundamentals of perfluorinated compounds. Northwest Biosolids Annual Meeting - Biofest, Portland, OR.

Pidlisnyuk V., Stefanovska T., Erickson L., Hettiarachichi G., Davis L., Shapoval P., Nurzhanova A. Using Miscantus x giganteus for restoration of former military sites.14th International Phytotehnologies Conference. Phytotechnologies: new sustainable solution for environmental challenges, IPC 2017, September 25-29, 2017, Montreal, Canada.

Pidlisnyuk V. ,Trogl J., Stefanovska T., Shapoval P., Nurzhanova A., Erickson L., Davis L., Hettiarachchi G. Phytotechnology with Miscanthus x giganteus biomass production for sustainable management of military sites. RemTech Europe conference on remediation market and technologies, Ferrara, Italy, September 20-22, 2017

Radovich T, Ahmad A., Hue N., Wang K., Silvasy T., Uyeda J., Sugano J., Gurr I., Gangaiah, Paull R. 2017. Optimizing local, organic compliant fertilizers for vegetable production in a crowded island environment. Amer. Soc. Hort. Sci. Conf., Waikoloa, Hawaii. Sept. 20, 2017.

Radolinski, J., J. X. Wu, K. Xia, and R. Stewart. 2016. Transport and fate of a neonicotinoid pesticide from corn seed coatings. ASA-CSSA-SSSA International Annual Meetings, Phoenix, AZ, Nov. 6-9.

Spokas. 2017. Biochars ability to sequester heavy metals in a mine impacted soil. American Society of Agronomy Meetings. October 22-25. Tampa. FL.

Spokas, K.A., and J.A. Ippolito. 2017. Biochar magic: The smoke and mirrors behind biochar use for improving soils. American Society of Agronomy Meetings. October 22-25. Tampa. FL.

Stone, S., Agioutantis, Z., Whittecar, G. R., Daniels, W. L., Thompson, T., & Dobbs, K. (2017). Wetbud – A Free Water Budget Modeling Tool for Created Wetland Design. In Z. Li, Z. Agioutantis, & H. Zou (Eds.), Proceedings, 8th International Conference on Sustainable Development in the Minerals Industry (pp. 182-188). Canada: Camdemia. Retrieved from http://www.camdemia.ca/publications

Willard L. L., Wynn-Thompson T., Krometis L. A. H., Neher T. P., and Badgley B. D. (2017). Does it pay to be mature? Evaluation of bioretention cell performance seven years post construction. J. Env. Eng. 143: 04017041.

Wind, L., L. H. Krometis, W. C. Hession, C. Q. Chen, P. Du, K. Jacobs, K. Xia, and Amy Pruden. 2018. Fate of Pirlimycin and Antibiotic-Resistant Fecal Coliforms in Field Plots Amended with Dairy Manure or Compost during Vegetable Cultivation. J. Environ. Qual. 47:436–444.

Wrage-Moennig, N., S. Fiedler, T. Fuertes-Mendizabal, J.M. Estavillo, J.A. Ippolito, N. Borchard, M. Cayuela, K.A. Spokas, J.M. Novak, and C. Kammann. 2017. Influence of 13 biochars on N2O sources during rewetting-drying cycles. American Society of Agronomy Meetings. October 22-25. Tampa. FL.

Extension publications

Silveira, M.L., G.A. O’Connor, and J. Vendramini. Utilization of biosolids in forage production systems in Florida. SL444 (EDIS # SS658).

Book Chapters

Brown, S.L. Making Soils from Urban Wastes.  2017. In Advances in Soil Science: Urban Soils R. Lal and B.A. Stewart (Ed) Taylor and Francis Publishers

Brown, S.L., A. Trlica, J. Lavery, and M. Teshima. 2017. Carbon sequestration potential on mined lands.  In Mine Site Rehabilitation and Restoration.  N. Bolan, M.B. Kirkham and Y. Ok (eds.)  Taylor and Francis Publishers

Daniels, W. L., Orndorff, Z. W., Stilson, C., Zimmerman, C., & Haywood, A. (2017). Development of Effective Rehabilitation Protocols for Mineral Sands Mining in Virginia USA. In Mined Land Reclamation: From Start to Finish. Carlton, VIC, Australia: Australia Institute for Mining and Minerals. Retrieved from http://www.ausimm.com/

Howard, J. L., & Daniels, W. L. (2017). Soils of urban and human-impacted landscapes. In D. Richardson, N. Castree, M. Goodchild, A. Kobayashi, W. Liu, & R. Marston (Eds.), The International Encyclopedia of Geography (pp. 1-9). Hoboken, NJ, USA: John Wiley and Sons.

Trade Journals

Brown, S. 2017. Connections- monthly column Biocycle magazine.

Hacheney, N. and S. Brown. 2017. Correctional facility adopts multiple food scrap practices.  Biocycle 58:9:34

Graduate Theses and Dissertations

Shultz, K. (12/2016) Effects of bioretention cell factors affecting the removal of stormwater N and P. Non-thesis M.S. Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg.

Sosienski, T. (7/2017) The Occurrence and Fate of Steroid Hormones from Manure Amended Agriculture Fields. Ph.D. dissertation. Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg.

Qin, C. (12/2016) Mineral Surface Catalyzed Polymerization of Estrogen and Microbial Deactivation by Fe³⁺-Saturated Montmorillonite: A Potentially Low Cost material for Water Decontamination. Ph.D. dissertation. Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg.