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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 3784

Fractionation and characterization of organic matter in wastewater from a swine waste-retention basin

Organic matter in wastewater sampled from a swine waste-retention basin in Iowa was fractionated into 14 fractions on the basis of size (particulate, colloid, and dissolved); volatility; polarity (hydrophobic, transphilic, hydrophilic); acid, base, neutral characteristics; and precipitate or flocculates (floc) formation upon acidification. The compound-class composition of each of these...
Authors
Jerry A. Leenheer, Colleen E. Rostad

Questa baseline and pre-mining ground-water-quality investigation. 16. Quality assurance and quality control for water analyses

The Questa baseline and pre-mining ground-water quality investigation has the main objective of inferring the ground-water chemistry at an active mine site. Hence, existing ground-water chemistry and its quality assurance and quality control is of crucial importance to this study and a substantial effort was spent on this activity. Analyses of seventy-two blanks demonstrated that...
Authors
R. Blaine McCleskey, D. Kirk Nordstrom, Cheryl A. Naus

Scientific advances provide opportunities to improve pediatric environmental health

The health consequences of contaminants in the environment, with respect to the health of children and infants, recently have been dramatically brought to public attention by the motion pictures Erin Brockovich and A Civil Action. These productions focused public attention on the potential link between water contaminants and pediatric health, a continuing subject of public concern. As a...
Authors
Michael M. Reddy, Micaela B. Reddy, Carol F. Reddy

Tannins and terpenoids as major precursors of Suwannee River fulvic acid

Suwannee River fulvic acid (SRFA) was fractionated into 7 fractions by normal-phase chromatography on silica gel followed by reverse-phase fractionation on XAD-8 resin that produced 18 subfractions. Selected major subfractions were characterized by 13C-nuclear magnetic resonance (NMR), infrared spectrometry, and elemental analyses. 13C-NMR spectra of the subfractions were more indicative...
Authors
Jerry A. Leenheer, Colleen E. Rostad

Transient Analysis of the Source of Water to Wells: Cape Cod, Massachusetts

A transient flow modeling analysis for potential public-supply wells on western Cape Cod, Massachusetts, demonstrates the difference between transient and steady-state recharge areas can have important implications for wellhead protection. An example of a single pumping well illustrates that commonly, used steady-state time-related capture areas do not represent the recharge area and...
Authors
John P. Masterson, D. A. Walter, D.R. LeBlanc

Importance of equilibration time in the partitioning and toxicity of zinc in spiked sediment bioassays

The influences of spiked Zn concentrations (1–40 μmol/g) and equilibration time (˜ 95 d) on the partitioning of Zn between pore water (PW) and sediment were evaluated with estuarine sediments containing two levels (5 and 15 μmol/g) of acid volatile sulfides (AVS). Their influence on Zn bioavailability was also evaluated by a parallel, 10‐d amphipod (Leptocheirus plumulosus) mortality...
Authors
J.-S. Lee, B.-G. Lee, S. N. Luoma, H. Yoo

Changes in snowmelt runoff timing in western North America under a 'business as usual' climate change scenario

Spring snowmelt is the most important contribution of many rivers in western North America. If climate changes, this contribution may change. A shift in the timing of springtime snowmelt towards earlier in the year already is observed during 1948-2000 in many western rivers. Streamflow timing changes for the 1995-2099 period are projected using regression relations between observed...
Authors
I.T. Stewart, Daniel Cayan, Michael D. Dettinger

Importance of the Vadose Zone in analyses of unconfined aquifer tests

Analytical models commonly used to interpret unconfined aquifer tests have been based on upper-boundary (water table) conditions that do not adequately address effects of time-varying drainage from the vadose zone. As a result, measured and simulated drawdown data may not agree and hydraulic parameters may be inaccurately estimated. A 72-hour aquifer test conducted in Cape Cod...
Authors
A.F. Moench
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