Two wastewater treatment plants (WWTPs) of northern Colorado were monitored for anhydroerythromyc... more Two wastewater treatment plants (WWTPs) of northern Colorado were monitored for anhydroerythromycin and tylosin. An analytical method has been developed and validated for the trace determination and confirmation of these compounds in the raw influent and final effluent water matrices. This method was used to evaluate the occurrence and fate of these compounds in WWTPs. The method uses solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Detection and quantification was performed using selected reaction monitoring, and a method detection limit of between 0.01 and 0.06 μg/L was obtained. Unequivocal confirmation analysis of analyte identity according to the criteria (based on the use of identification points) of the 2002/657/EC European Commission Decision was possible with satisfactory results. Average recoveries for the two compounds ranged from 89.2±9.7% for raw influent to 93.7±6.9% for effluent wastewaters. The within-run precision of the assay was found to be always less than 14.1% for the two analytes. The overall precision was always less than 13.7%. The relative uncertainty of the present assay was also evaluated and the combined relative uncertainty ranged from 6.4 to 15.5% over three days of the validation study. These compounds were partially removed in the WWTPs with a removal efficiency of >50%. The measured concentrations in raw influents and effluents ranged from 0.09-0.35 and 0.04-0.12 μg/L for anhydroerythromycin to 0.06-0.18 and ND-0.06 μg/L for tylosin, respectively. The results indicate that WWTP effluents are relevant point sources for residues of these compounds in the aquatic environment. These occurrence results were compared with those in WWTP wastewaters of other countries.
A river along the semi-arid Front Range of Colorado was monitored for antibiotics including five ... more A river along the semi-arid Front Range of Colorado was monitored for antibiotics including five tetracycline and six sulfonamide compounds. Existing analytical methods were adapted to measure these compounds in a surface water matrix at environmentally relevant concentrations (0.05 mg/L). Natural organic matter present in surface waters was confirmed to significantly impact the low-level analysis of tetracyclines (TCs) necessitating the use of standard addition quantification techniques. Five sites along the Cache la Poudre River were monitored for antibiotics encompassing pristine areas without anthropogenic influence, urban areas impacted by wastewater discharges and agricultural areas susceptible to non-point source contaminant runoff. The only site at which no antibiotics were detected was the pristine site in the mountains before the river had encountered urban or agricultural landscapes. By the time the river had exited the urban area, 6 of the 11 antibiotic compounds that were monitored were found in the samples. At Site 5, which had both urban and agricultural influences all five of the TCs monitored were detected indicating both urban and agricultural influences. The concentration of TCs at Site 5 ranged from 0.08 to 0.30 mg/L.
Excess nutrients are among the leading sources of water quality impairment in the Unites States, ... more Excess nutrients are among the leading sources of water quality impairment in the Unites States, and the USEPA has been working with state regulatory agencies to develop nutrient criteria for wastewater treatment plants (WWTPs). The Colorado Department of Public Health and Environment is scheduled to establish nutrient regulations in 2013, and stream total P (TP) concentration standards of 0.16 mg L-1 in warm water and 0.11 mg L-1 in cold water have been proposed for the rivers in the state. The objectives of this study were to monitor TP concentrations and loads along the Cache La Poudre River as it flows from the pristine upstream area through urban regions and finally through a mixture of agricultural and urban land uses. The study attempts to evaluate the sources and influences of TP under different hydrologic conditions. Twelve sampling events were completed from April 2010 to August 2011 to assess the influence of various flow and precipitation conditions on aqueous TP concentrations. During midrange flows and dry conditions, WWTPs were the major sources of TP, but other sources were more significant under high-flow and wet conditions according to a load analysis. The analysis indicates that reducing the TP load from WWTPs will only marginally affect the TP load in the river, and therefore it appears that other sources (e.g., stormwater and agricultural runoff) need to be addressed before the aquatic life-based stream standard can be achieved.
An analytical method was developed and tested for four different groups of veterinary antibiotics... more An analytical method was developed and tested for four different groups of veterinary antibiotics in both river water and sediment matrices. Solid phase extraction (SPE) was used to enrich and to clean up the aqueous sample. Also, Mcllvaine and ammonium hydroxide buffer solutions were used to extract the compounds from the sediment matrix. High performance liquid chromatography (HPLC) equipped with tandem mass spectrometry (MS/ MS) was used to separate and quantify the samples. The range of recoveries (in percent) for tetracyclines (TCs), sulfonamides (SAs), macrolides (MLs), and ionophore polyethers (IPs) in the water matrix were 102.2-124.8, 76.6-124.3, 89.5-114.7, 82.7-117.5 with 1-13 (%) of relative standard deviation respectively with three different concentrations. For sediment, the percent recovery ranges were 32.8-114.8, 62.4-108.9, 53.4-128.4 and 51.3-105.4 for TCs, SAs, MLs and IPs, respectively. The relative standard deviation ranged from 16-27 (%) over three different concentrations. The limit of quantification (LOQ) was determined by two different methods and calculated to be in the range of 0.01-0.04 μg/l and 0.3-2.5 μg/kg for TCs, SAs, and MLs in water and sediment, respectively. For IPs, the LOQ was 0.001-0.003 μg/l in river water and 0.4-3.6 μg/kg for sediment. The sediment concentration measured in an agriculture-influenced river was much higher than in the overlying water matrix, indicating a high degree of sediment partitioning for these compounds.
Presented at the Fall 2013 Center for Collaborative Conservation (http://www.collaborativeconserv... more Presented at the Fall 2013 Center for Collaborative Conservation (http://www.collaborativeconservation.org/) Seminar and Discussion Series, "Community, Energy Development and the Environment", September 10, 2013, Colorado State University, Fort Collins, Colorado. This series focused on the work that the CCC's Collaborative Conservation Fellows have been doing across the Western U.S. and around the world.
A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography-... more A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography-ion trap tandem mass spectrometry (LC-MS-MS) has been developed for determination of trace concentrations of erythromycin-H 2 O (ETM-H 2 O), roxithromycin (RTM) and tylosin (TLS) in natural and waste water matrices. These macrolides (MLs) were extracted from water samples using Oasis HLB cartridges, and the average recovery was 93.6 ± 8.6, 92.1 ± 10.0, and 94.3 ± 8.9% for ETM-H 2 O, RTM and TLS in surface water, respectively. For water from the influent of a wastewater treatment plant (WWTP), the average recovery was 84.8 ± 14.0, 83.2 ± 13.1, and 86.1 ± 13.4% for ETM-H 2 O, RTM and TLS, respectively. Method detection limits in a natural water matrices were 0.07, 0.03, and 0.05 g/l for ETM-H 2 O, RTM, and TLS, respectively. Fragment or product ions from MS spectra using in-source collision-induced dissociation and MS-MS spectra have been identified. The accuracy and day-today variation of the method fell within acceptable ranges. The method was evaluated by studying the occurrence of the three macrolides on a river and a WWTP in northern Colorado. None of the antibiotics were detected in the stream except immediately downstream of a WWTP, a result consistent with their presence in the influent and effluent of the treatment facility.
A series of filtration steps was used to seperate iron (Fe) and manganese (Mn) into soluble, coll... more A series of filtration steps was used to seperate iron (Fe) and manganese (Mn) into soluble, colloidal, and particulate fractions. Two case studies demonstrate how fractionation data can improve understanding of the origins and removal of Fe amd Mn. The Mn species present in one water source were shown to be regulated by a biogeochemical cycle in which the natural
Veterinary antibiotics, leached from contaminated manure that is applied as fertilizer, could be ... more Veterinary antibiotics, leached from contaminated manure that is applied as fertilizer, could be transported to surface water as runoff or infiltrated to groundwater after a significant rainfall. The main objective of this study was to evaluate the transport behaviour of ten antibiotics belonging to four different groups in soil through the column leaching study under biotic and abiotic conditions. Among compared antibiotic groups, tetracyclines (TCs) were found to have no residual in the leachate and mainly remained sorbed to the fixed column soil ranging 34~81% of initially applied mass. In contrast, sulfamethazine(SMTs), one of the sulfonamides (SAs) group, was mostly recovered in the leachate at the ranges of 74~83% of the total mass applied. Also, colloidal-facilitated transport of antibiotics was observed. Depending on the antibiotics, recovered mass of colloidal-facilitated transport was 0.4~22.7% for biotic and 0.2~62.5% for abiotic treatment as compared to total mass applie...
ABSTRACT Pilot-scale biofiltration experiments were conducted to determine how empty bed contact ... more ABSTRACT Pilot-scale biofiltration experiments were conducted to determine how empty bed contact time (EBCT) and hydraulic loading rate (HLR) affected the removal of biodegradable organic matter (BOM). The removal of BOM formed during ozonation was measured as the reduction (resulting from biodegradation) of dissolved organic carbon in the filter; it was referred to as biodegradable dissolved organic carbon-filter (BDOCfilter). Ten ozone by-products were measured to understand the composition of BDOCfilter and to assess whether these by-products might be used as a surrogate for BOM; none sufficed. BOM formed during ozonation limited the removal of BDOC during biofiltration with two exceptions: nonsteady-state BOM loading conditions and inadequate EBCT. Both of these conditions were limited by biomass formation. HLR had no effect on BDOCfilter even though markedly different biomass profiles were observed.
Two typical animal waste management practices, composting and stockpiling, were evaluated for the... more Two typical animal waste management practices, composting and stockpiling, were evaluated for their effect on the degradation of three veterinary antibiotics (VAs), chlortetracycline (CTC), tylosin (TYL), and monensin (MNS). The VAs were applied to horse manure plots subject to composting or stockpiling, and core samples were collected over a period of time. Selected buffer solutions were used to extract the VAs and analysis for concentration was conducted with solid phase extraction (SPE) followed by high performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) technique. The VAs demonstrated rapid dissipation within ten days followed by a gradual decrease in concentration until the end of the experimental period (141 days). All three VAs degraded more rapidly in the composting samples than in the stockpiling samples, particularly between 20 and 60 days of the observation period. Degradation of the three VAs generally followed a first-order kinetic model, and a fitted model with a calculated rate constant was determined for each treatment. TYL in composting showed the fastest degradation, with a calculated rate constant of 0.91 day-1 ; the slowest degradation was exhibited by MNS in stockpiling, with rate constant of 0.17 day-1. Calculated correlation coefficients ranged from 0.89 to 0.96, indicating a strong correlation between measured concentrations and fitted values in this study. Although concentration of TYL in composting treatment showed below detection limit during the test period, this study suggests that composting can reduce animal waste contaminants prior to field application as fertilizer.
High volumes of flowback and produced water are generated everyday as a byproduct of hydraulic fr... more High volumes of flowback and produced water are generated everyday as a byproduct of hydraulic fracturing operations and shale gas developments across the United States. Since most shale gas developments are located in semi-arid to arid U.S. regions close to agricultural production, there are many opportunities for reusing these waters as potential alternatives or supplements to fresh water resources for irrigation activities. However, the impacts of high salinity and total organic content of these types of water on crop physiological parameters and plant growth needs to be investigated to determine their utility and feasibility. The aim of the present study was to evaluate the response of switchgrass and rapeseed to treated produced water as an irrigation water source. In this greenhouse study, the influence of produced water at four total organic carbon (TOC) concentrations [1.22, 38.3, 232.2 and 1352.4 mg/l] and three total dissolved solids (TDS) levels [400, 3,500, and 21,000 mg/l] on rapeseed (Brassica napus L.) and switchgrass (Panicum virgatum L.), two relatively salt-tolerant, non-food, biofuel crops, was
Water management and water re-use strategies play an important role in minimising the costs and r... more Water management and water re-use strategies play an important role in minimising the costs and risks associated with the development of an unconventional oil and gas field. At the same time, an effective water management strategy is essential to maintain a social license to operate and minimise the social and environmental impacts associated with development. Most companies, however, are forced to make water decisions based solely on the flexibility of a water management strategy that can accommodate changes in a development plan. In most situations, this is the most expensive option with the highest environmental and social risk. MWH Global has developed a streamlined water infrastructure modelling approach that gives users the ability to quickly visualise a variety of water management and water re-use strategies for different development plans. The user can quantitatively compare key outputs (such as costs, flexibility, probability of a traffic accident and CO2 emissions) for dif...
Two wastewater treatment plants (WWTPs) of northern Colorado were monitored for anhydroerythromyc... more Two wastewater treatment plants (WWTPs) of northern Colorado were monitored for anhydroerythromycin and tylosin. An analytical method has been developed and validated for the trace determination and confirmation of these compounds in the raw influent and final effluent water matrices. This method was used to evaluate the occurrence and fate of these compounds in WWTPs. The method uses solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Detection and quantification was performed using selected reaction monitoring, and a method detection limit of between 0.01 and 0.06 μg/L was obtained. Unequivocal confirmation analysis of analyte identity according to the criteria (based on the use of identification points) of the 2002/657/EC European Commission Decision was possible with satisfactory results. Average recoveries for the two compounds ranged from 89.2±9.7% for raw influent to 93.7±6.9% for effluent wastewaters. The within-run precision of the assay was found to be always less than 14.1% for the two analytes. The overall precision was always less than 13.7%. The relative uncertainty of the present assay was also evaluated and the combined relative uncertainty ranged from 6.4 to 15.5% over three days of the validation study. These compounds were partially removed in the WWTPs with a removal efficiency of >50%. The measured concentrations in raw influents and effluents ranged from 0.09-0.35 and 0.04-0.12 μg/L for anhydroerythromycin to 0.06-0.18 and ND-0.06 μg/L for tylosin, respectively. The results indicate that WWTP effluents are relevant point sources for residues of these compounds in the aquatic environment. These occurrence results were compared with those in WWTP wastewaters of other countries.
A river along the semi-arid Front Range of Colorado was monitored for antibiotics including five ... more A river along the semi-arid Front Range of Colorado was monitored for antibiotics including five tetracycline and six sulfonamide compounds. Existing analytical methods were adapted to measure these compounds in a surface water matrix at environmentally relevant concentrations (0.05 mg/L). Natural organic matter present in surface waters was confirmed to significantly impact the low-level analysis of tetracyclines (TCs) necessitating the use of standard addition quantification techniques. Five sites along the Cache la Poudre River were monitored for antibiotics encompassing pristine areas without anthropogenic influence, urban areas impacted by wastewater discharges and agricultural areas susceptible to non-point source contaminant runoff. The only site at which no antibiotics were detected was the pristine site in the mountains before the river had encountered urban or agricultural landscapes. By the time the river had exited the urban area, 6 of the 11 antibiotic compounds that were monitored were found in the samples. At Site 5, which had both urban and agricultural influences all five of the TCs monitored were detected indicating both urban and agricultural influences. The concentration of TCs at Site 5 ranged from 0.08 to 0.30 mg/L.
Excess nutrients are among the leading sources of water quality impairment in the Unites States, ... more Excess nutrients are among the leading sources of water quality impairment in the Unites States, and the USEPA has been working with state regulatory agencies to develop nutrient criteria for wastewater treatment plants (WWTPs). The Colorado Department of Public Health and Environment is scheduled to establish nutrient regulations in 2013, and stream total P (TP) concentration standards of 0.16 mg L-1 in warm water and 0.11 mg L-1 in cold water have been proposed for the rivers in the state. The objectives of this study were to monitor TP concentrations and loads along the Cache La Poudre River as it flows from the pristine upstream area through urban regions and finally through a mixture of agricultural and urban land uses. The study attempts to evaluate the sources and influences of TP under different hydrologic conditions. Twelve sampling events were completed from April 2010 to August 2011 to assess the influence of various flow and precipitation conditions on aqueous TP concentrations. During midrange flows and dry conditions, WWTPs were the major sources of TP, but other sources were more significant under high-flow and wet conditions according to a load analysis. The analysis indicates that reducing the TP load from WWTPs will only marginally affect the TP load in the river, and therefore it appears that other sources (e.g., stormwater and agricultural runoff) need to be addressed before the aquatic life-based stream standard can be achieved.
An analytical method was developed and tested for four different groups of veterinary antibiotics... more An analytical method was developed and tested for four different groups of veterinary antibiotics in both river water and sediment matrices. Solid phase extraction (SPE) was used to enrich and to clean up the aqueous sample. Also, Mcllvaine and ammonium hydroxide buffer solutions were used to extract the compounds from the sediment matrix. High performance liquid chromatography (HPLC) equipped with tandem mass spectrometry (MS/ MS) was used to separate and quantify the samples. The range of recoveries (in percent) for tetracyclines (TCs), sulfonamides (SAs), macrolides (MLs), and ionophore polyethers (IPs) in the water matrix were 102.2-124.8, 76.6-124.3, 89.5-114.7, 82.7-117.5 with 1-13 (%) of relative standard deviation respectively with three different concentrations. For sediment, the percent recovery ranges were 32.8-114.8, 62.4-108.9, 53.4-128.4 and 51.3-105.4 for TCs, SAs, MLs and IPs, respectively. The relative standard deviation ranged from 16-27 (%) over three different concentrations. The limit of quantification (LOQ) was determined by two different methods and calculated to be in the range of 0.01-0.04 μg/l and 0.3-2.5 μg/kg for TCs, SAs, and MLs in water and sediment, respectively. For IPs, the LOQ was 0.001-0.003 μg/l in river water and 0.4-3.6 μg/kg for sediment. The sediment concentration measured in an agriculture-influenced river was much higher than in the overlying water matrix, indicating a high degree of sediment partitioning for these compounds.
Presented at the Fall 2013 Center for Collaborative Conservation (http://www.collaborativeconserv... more Presented at the Fall 2013 Center for Collaborative Conservation (http://www.collaborativeconservation.org/) Seminar and Discussion Series, "Community, Energy Development and the Environment", September 10, 2013, Colorado State University, Fort Collins, Colorado. This series focused on the work that the CCC's Collaborative Conservation Fellows have been doing across the Western U.S. and around the world.
A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography-... more A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography-ion trap tandem mass spectrometry (LC-MS-MS) has been developed for determination of trace concentrations of erythromycin-H 2 O (ETM-H 2 O), roxithromycin (RTM) and tylosin (TLS) in natural and waste water matrices. These macrolides (MLs) were extracted from water samples using Oasis HLB cartridges, and the average recovery was 93.6 ± 8.6, 92.1 ± 10.0, and 94.3 ± 8.9% for ETM-H 2 O, RTM and TLS in surface water, respectively. For water from the influent of a wastewater treatment plant (WWTP), the average recovery was 84.8 ± 14.0, 83.2 ± 13.1, and 86.1 ± 13.4% for ETM-H 2 O, RTM and TLS, respectively. Method detection limits in a natural water matrices were 0.07, 0.03, and 0.05 g/l for ETM-H 2 O, RTM, and TLS, respectively. Fragment or product ions from MS spectra using in-source collision-induced dissociation and MS-MS spectra have been identified. The accuracy and day-today variation of the method fell within acceptable ranges. The method was evaluated by studying the occurrence of the three macrolides on a river and a WWTP in northern Colorado. None of the antibiotics were detected in the stream except immediately downstream of a WWTP, a result consistent with their presence in the influent and effluent of the treatment facility.
A series of filtration steps was used to seperate iron (Fe) and manganese (Mn) into soluble, coll... more A series of filtration steps was used to seperate iron (Fe) and manganese (Mn) into soluble, colloidal, and particulate fractions. Two case studies demonstrate how fractionation data can improve understanding of the origins and removal of Fe amd Mn. The Mn species present in one water source were shown to be regulated by a biogeochemical cycle in which the natural
Veterinary antibiotics, leached from contaminated manure that is applied as fertilizer, could be ... more Veterinary antibiotics, leached from contaminated manure that is applied as fertilizer, could be transported to surface water as runoff or infiltrated to groundwater after a significant rainfall. The main objective of this study was to evaluate the transport behaviour of ten antibiotics belonging to four different groups in soil through the column leaching study under biotic and abiotic conditions. Among compared antibiotic groups, tetracyclines (TCs) were found to have no residual in the leachate and mainly remained sorbed to the fixed column soil ranging 34~81% of initially applied mass. In contrast, sulfamethazine(SMTs), one of the sulfonamides (SAs) group, was mostly recovered in the leachate at the ranges of 74~83% of the total mass applied. Also, colloidal-facilitated transport of antibiotics was observed. Depending on the antibiotics, recovered mass of colloidal-facilitated transport was 0.4~22.7% for biotic and 0.2~62.5% for abiotic treatment as compared to total mass applie...
ABSTRACT Pilot-scale biofiltration experiments were conducted to determine how empty bed contact ... more ABSTRACT Pilot-scale biofiltration experiments were conducted to determine how empty bed contact time (EBCT) and hydraulic loading rate (HLR) affected the removal of biodegradable organic matter (BOM). The removal of BOM formed during ozonation was measured as the reduction (resulting from biodegradation) of dissolved organic carbon in the filter; it was referred to as biodegradable dissolved organic carbon-filter (BDOCfilter). Ten ozone by-products were measured to understand the composition of BDOCfilter and to assess whether these by-products might be used as a surrogate for BOM; none sufficed. BOM formed during ozonation limited the removal of BDOC during biofiltration with two exceptions: nonsteady-state BOM loading conditions and inadequate EBCT. Both of these conditions were limited by biomass formation. HLR had no effect on BDOCfilter even though markedly different biomass profiles were observed.
Two typical animal waste management practices, composting and stockpiling, were evaluated for the... more Two typical animal waste management practices, composting and stockpiling, were evaluated for their effect on the degradation of three veterinary antibiotics (VAs), chlortetracycline (CTC), tylosin (TYL), and monensin (MNS). The VAs were applied to horse manure plots subject to composting or stockpiling, and core samples were collected over a period of time. Selected buffer solutions were used to extract the VAs and analysis for concentration was conducted with solid phase extraction (SPE) followed by high performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) technique. The VAs demonstrated rapid dissipation within ten days followed by a gradual decrease in concentration until the end of the experimental period (141 days). All three VAs degraded more rapidly in the composting samples than in the stockpiling samples, particularly between 20 and 60 days of the observation period. Degradation of the three VAs generally followed a first-order kinetic model, and a fitted model with a calculated rate constant was determined for each treatment. TYL in composting showed the fastest degradation, with a calculated rate constant of 0.91 day-1 ; the slowest degradation was exhibited by MNS in stockpiling, with rate constant of 0.17 day-1. Calculated correlation coefficients ranged from 0.89 to 0.96, indicating a strong correlation between measured concentrations and fitted values in this study. Although concentration of TYL in composting treatment showed below detection limit during the test period, this study suggests that composting can reduce animal waste contaminants prior to field application as fertilizer.
High volumes of flowback and produced water are generated everyday as a byproduct of hydraulic fr... more High volumes of flowback and produced water are generated everyday as a byproduct of hydraulic fracturing operations and shale gas developments across the United States. Since most shale gas developments are located in semi-arid to arid U.S. regions close to agricultural production, there are many opportunities for reusing these waters as potential alternatives or supplements to fresh water resources for irrigation activities. However, the impacts of high salinity and total organic content of these types of water on crop physiological parameters and plant growth needs to be investigated to determine their utility and feasibility. The aim of the present study was to evaluate the response of switchgrass and rapeseed to treated produced water as an irrigation water source. In this greenhouse study, the influence of produced water at four total organic carbon (TOC) concentrations [1.22, 38.3, 232.2 and 1352.4 mg/l] and three total dissolved solids (TDS) levels [400, 3,500, and 21,000 mg/l] on rapeseed (Brassica napus L.) and switchgrass (Panicum virgatum L.), two relatively salt-tolerant, non-food, biofuel crops, was
Water management and water re-use strategies play an important role in minimising the costs and r... more Water management and water re-use strategies play an important role in minimising the costs and risks associated with the development of an unconventional oil and gas field. At the same time, an effective water management strategy is essential to maintain a social license to operate and minimise the social and environmental impacts associated with development. Most companies, however, are forced to make water decisions based solely on the flexibility of a water management strategy that can accommodate changes in a development plan. In most situations, this is the most expensive option with the highest environmental and social risk. MWH Global has developed a streamlined water infrastructure modelling approach that gives users the ability to quickly visualise a variety of water management and water re-use strategies for different development plans. The user can quantitatively compare key outputs (such as costs, flexibility, probability of a traffic accident and CO2 emissions) for dif...
Uploads
Papers by Ken Carlson