Huber D.R.,U.S. Environmental Protection Agency |
Blount B.C.,Centers for Disease Control and Prevention |
Mage D.T.,Danya International, Inc. |
Letkiewicz F.J.,Cadmus Group Inc. |
And 2 more authors.
Journal of Exposure Science and Environmental Epidemiology | Year: 2011
Human biomonitoring data show that exposure to perchlorate is widespread in the United States. The predominant source of intake is food, whereas drinking water is a less frequent and far smaller contributor. We used spot urine samples for over 2700 subjects and estimated 24 h intake using new creatinine adjustment equations. Merging data from surveys of national health (NHANES) with drinking water monitoring (UCMR), we categorized survey participants according to their potential exposure through drinking water or food. By subtracting daily food doses of perchlorate from the oral reference dose (RfD), we derive an allowances for perchlorate in tap water for several populations. The calculated mean food perchlorate dose in the United States was 0.081 g/kg/day compared to 0.101 g/kg/day for those who also had a potential drinking water component. The calculated 95th percentile doses, typically falling between 0.2 and 0.4 g/kg/day, were well below the RfD (0.7 g/kg/day) in all populations analyzed. Children aged 6-11 years had the highest mean perchlorate doses in food (0.147 g/kg/day), with an additional water contribution of only 0.003 g/kg/day representing just 2% of exposure. Pregnant women had a mean food dose of 0.093 vs 0.071 g/kg/day for all women of reproductive age. At the 95th percentile intake for both the total population and women of child-bearing age (15-44), the perchlorate contribution from food was 86% and from drinking water 14% (respectively, 30% and 5% of the RfD). At the mean for the same groups, the food to water contribution ratio is approximately 80:20. We calculate that an average 66 kg pregnant woman consuming a 90th percentile food dose (0.198 g/kg/day) could also drink the 90th percentile of community water for pregnant women (0.033 l/kg/day) containing 15 g/l perchlorate without exceeding the 0.7 g/kg/day reference dose.
van Egeren S.J.,801 Progress Rd |
Dodson S.I.,University of Wisconsin - Madison |
Torke B.,3119 W. Petty Road |
Maxted J.T.,Cadmus Group Inc.
Hydrobiologia | Year: 2011
Zooplankton community composition can be related to natural environmental factors such as lake morphology, lake landscape position, and water chemistry as well as anthropogenic factors such as agricultural and urban land-use. We hypothesized that within-lake factors, such as water chemistry, lake morphology, and human land-use would each be related to zooplankton community structure, but that watershed land-use would be the strongest correlate in southeast Wisconsin lakes. Zooplankton samples, collected every 3 months over a year, from 29 lakes were used to determine how lake and watershed morphology, water quality, and land-use were related to zooplankton community structure in the heavily developed Southeast Wisconsin Till Plain Ecoregion. Forward selection and a variation partitioning procedure were used to determine relative and shared contributions of each suite of variables in predicting zooplankton community structure. Redundancy analysis was used to characterize dominant gradients in pelagic zooplankton communities and related environmental factors and land-use. The major correlates of community structure included summer phosphorus, lake depth and surface area and urban and natural land. Variation partitioning illustrated that phosphorus alone accounts for the greatest part (12%) of community structure. Urban land-uses (residential, commercial and paved land) and lake morphology partially explain zooplankton community variation through combined effects with phosphorus. Small cladocerans and Skistodiaptomus pallidus were associated with higher phosphorus, shallow depth and higher urban land-use, while Daphnia pulicaria dominates in deep lakes with lower phosphorus and less urban land-use. This study contributes to the understanding of factors affecting zooplankton community structure in a largely human developed region and illustrates the importance of eutrophication in structuring zooplankton community composition. © 2011 Springer Science+Business Media B.V.
Stankwitz C.,College of William and Mary |
Stankwitz C.,Cadmus Group Inc. |
Kaste J.M.,College of William and Mary |
Friedland A.J.,Dartmouth College
Environmental Science and Technology | Year: 2012
Atmospheric deposition is the primary mechanism by which remote ecosystems are contaminated, but few data sets show how fluxes change and control soil metal burdens at the landform scale. We present mercury (Hg), lead ( 210Pb and total Pb), and cosmogenic beryllium-7 (7Be) measurements in organic (O) soil horizons at high-resolution elevation intervals of ∼60 m from 540 to 1160 m on Camels Hump in northern Vermont, USA. Across this gradient, average O horizon Hg ranges from 0.99 mg m-2 in the low elevation deciduous forest zone to 7.6 mg m-2 in the higher elevation coniferous forest at 1030 m. We measure two pronounced threshold increases in soil metal burdens above 801 and 934 m, corresponding to the two most common altitudes of cloud base, which coincide with changes in vegetation species. Lead-210, a unique tracer of tropospheric deposition, also increased from 3200 Bq m-2 to 11 500 Bq m-2 in O horizons, exhibiting threshold responses at the same elevations as Hg and total Pb. Concentrations of 210Pb and Hg in foliage double from 760 to 900 m elevation, indicating enhanced deposition across the transition from deciduous to coniferous forest. In contrast, 7Be is constant across the entire elevational gradient because of its upper atmospheric source. This indicates that the effects of orographic precipitation have a smaller control on soil contaminant burdens than the coupled cloudwater deposition-vegetation scavenging effect in the presence of upwind sources. By measuring soil contaminants and unique tracers of atmospheric deposition, we show that tropospheric fluxes of Hg and Pb are higher by a factor of 2 in high-elevation coniferous forests than in adjacent lowlands. Total O horizon Hg and Pb burdens increase by over 4-fold with elevation because of the compounding effects of enhanced deposition and longer metal residence times at higher elevations (>50 years). © 2012 American Chemical Society.
Koplos J.,Cadmus Group Inc. |
Tuccillo M.E.,Cadmus Group Inc. |
Ranalli B.,Cadmus Group Inc.
Journal - American Water Works Association | Year: 2014
Technological innovations in hydraulic fracturing combined with advanced directional drilling capabilities have transformed US oil and gas production. The process of hydraulic fracturing uses several million gallons of water and perhaps tens of thousands of gallons of chemical additives per production well to create fractures that enhance the flow of oil and gas from unconventional reservoirs. Reservoir geology and operator practices influence the amount of water and the mix of chemicals used in the hydraulic fracturing process as well as the amount and composition of the flowback and produced water generated during production. When the hydraulic fracturing process is complete and the injection pressure is stopped, the direction of fluid flow reverses. Some of the injected hydraulic fracturing fluid along with native formation fluids from the targeted production zone in the reservoir flow into the well and to the surface. The oil- and gas-bearing formations where hydraulic fracturing is commonly used generally range in depths from 5,000 to 10,000 ft. deep. However, gas resources in some shales and coalbeds that could be produced using hydraulic fracturing are less than 2,000 ft. deep.
Boyd G.R.,Cadmus Group Inc.
Journal - American Water Works Association | Year: 2012
Two galvanic pipe-loop couples (lead-copper and lead- bronze) were exposed to controlled changes in water quality (disinfectant, pH, alkalinity, phosphate) and monitored for changes in lead and copper release. Open circuit potential (OCP) profiles were also measured along the junction of dissimilar metals to determine the extent of the zone affected by galvanic coupling. Grab sampling results showed that changes in water quality caused transient (short-lived) increases in lead and decreases in copper that corresponded to the galvanic action of lead on the other coupled metal. OCP measurements showed that the galvanic effect on corrosion potential can induce a shift of up to 600 mV. The extent of the galvanically affected zone was limited, penetrating no more than a few inches from the juncture along the surface of each pipe. Additional testing confirmed strong effects of external versus direct coupling on the OCP profiles in the galvanically affected zone.
Mudarri D.H.,Cadmus Group Inc.
Journal of Environmental and Public Health | Year: 2016
Two foundational methods for estimating the total economic burden of disease are cost of illness (COI) and willingness to pay (WTP). WTP measures the full cost to society, but WTP estimates are difficult to compute and rarely available. COI methods are more often used but less likely to reflect full costs. This paper attempts to estimate the full economic cost (2014$) of illnesses resulting from exposure to dampness and mold using COI methods and WTP where the data is available. A limited sensitivity analysis of alternative methods and assumptions demonstrates a wide potential range of estimates. In the final estimates, the total annual cost to society attributable to dampness and mold is estimated to be $3.7 (2.3-4.7) billion for allergic rhinitis, $1.9 (1.1-2.3) billion for acute bronchitis, $15.1 (9.4-20.6) billion for asthma morbidity, and $1.7 (0.4-4.5) billion for asthma mortality. The corresponding costs from all causes, not limited to dampness and mold, using the same approach would be $24.8 billion for allergic rhinitis, $13.5 billion for acute bronchitis, $94.5 billion for asthma morbidity, and $10.8 billion for asthma mortality. © 2016 David H. Mudarri.
Blake L.J.,Cadmus Group Inc.
ASABE - TMDL 2010: Watershed Management to Improve Water Quality | Year: 2010
In 2008, the U.S. Environmental Protection Agency (EPA) funded a project to collect information on how states are measuring and demonstrating water quality improvements and attainment with water quality standards for use in reporting measures such as National Water Program Guidance Measure SP-12. EPA has asked states to meet 2012 reporting goals for Measure SP-12. The national goal is to provide Measure SP-12 reports on at least 250 watersheds by 2012; this goal is broken down into EPA region specific reporting targets (e.g., 5 per state). Achieving Measure SP-12 goals will require a collaborative effort on the part of EPA, state agencies, and local partners. The goal of this report is to present a synthesis of key technical, programmatic, and resource information obtained from the nine states on current approaches and state needs for measuring and demonstrating water quality improvements and attainment with water quality standards for SP-12 Watersheds (and all watersheds in general); further, in response to challenges identified and request made by the participating states, this report also provides strategic planning recommendations for supporting effectiveness monitoring, tracking, and assessment. Specifically, this report includes the following: • A summary of how each of nine states is measuring and demonstrating water quality improvements and attainment with water quality standards for SP-12 Watersheds, as well as other watersheds; • An overview of the type of data being used by states to satisfy reporting requirements for Measure SP-12 and other performance measures; • Existing protocols, approaches, and viable options for effectiveness monitoring while considering the diverse geographic, land use, and pollutant sources found in the interviewed states; • Potential options for combining existing monitoring and assessments efforts to address reporting needs for multiple various performance measures; • Recommendations and feedback on issues, challenges, and needs identified by the states.
Tracy Mehan III G.,Cadmus Group Inc. |
Kline I.,Cadmus Group Inc.
Journal - American Water Works Association | Year: 2012
Issues relating to pricing as a demand-side management tool are discussed. It is found that the challenges of an aging and underfinanced infrastructure are affected by a growing and shifting population into arid areas in the midst of drought, climate change, and water shortages, creating major challenges to sustainable water management. Utility and system managers, governing boards, and regulators must ensure that the price of water services fairly reflects their full value to human health and the environment and recovers the costs of maintaining, operating, and replacing invaluable infrastructure. In this direction, in North America, there is an increasing appreciation of the need for new tools and multi- or interdisciplinary approaches, on the demand side as much as the supply side, for nonstructural as well as structural techniques, and engineering along with nonengineering tools.
Girman J.,Cadmus Group Inc.
12th International Conference on Indoor Air Quality and Climate 2011 | Year: 2011
This paper lists many research needs that must be addressed to allow us to mitigate the impacts of climate change without degrading energy efficiency and without increasing our carbon footprint. The needs are organized around likely impacts of climate change and their connections to the indoor environment. The list of research needs is not comprehensive but is intended to prompt discussion within the research community and with policy makers so that critical research needs are developed and addressed.
Weir L.,Cadmus Group Inc. |
Roberson J.A.,Cadmus Group Inc.
Journal / American Water Works Association | Year: 2011
National noncompliance with the nitrate regulation is up to a level comparable to where it was in 1993-two years after nitrate regulations were enacted. More research is needed to understand if this noncompliance is the result of additional water source contamination, sources moving in and out of compliance, or nitrate treatment not being properly operated. In response to the high number of ongoing violations and the potential for nitrate standards to be revised, the authors conducted a study to estimate the national costs of complying with the current nitrate standard of 10 mg/L and a potentially more stringent standard of 5 mg/L. This article puts the national compliance costs into context with the nitrate regulation when compared with the compliance costs of other water regulations and puts forward additional drinking water policy questions that warrant future research.