54 research outputs found
CHARACTERIZATION OF ESCHERICHIA COLI RELATED TO CONSTRUCTION SITE SEDIMENT BASINS
Large construction sites can have significant temporary and permanent impacts on the physical landscape. Excess sediment is frequently deposited into nearby surface waters, altering benthic habitat, reducing water clarity and transporting other pollutants such as enteric bacteria. To capture eroded soil and attenuate storm discharge peaks, many permitted construction projects larger than 10 acres in South Carolina require the installation of a sediment basin. Sediment-laden runoff is routed to a newly excavated impoundment, where larger particles settle out of suspension. Thus an entirely new hydrologic feature designed to concentrate eroded sediment and water is introduced into the landscape. Eight construction projects and their associated sediment basins were monitored in Anderson, SC during the spring, summer and autumn of 2008 to evaluate Escherichia coli (E. coli) densities and assess relationships with observed environmental variables. Dry and wet-weather samples were collected from basin inlets, outlets, water column and deposited sediments. Bacterial concentrations from construction site runoff measured at inlets (mean = 771 MPN/100 ml) were consistently and significantly higher than water quality criteria established for primary contact recreation by the US Environmental Protection Agency. Basin discharge measured at outlets showed significantly higher bacterial concentrations (mean = 1368 MPN/ 100 ml; t-stat = 3.54; p = .0036) than those found in construction site runoff and also exceeded EPA standards. Within sediment basins, both mean water column (877 MPN/100 ml) and mean sediment (1.8E+5 MPN/100 ml) E. coli densities were higher than recommended EPA criteria, with mean concentrations in the sediments significantly exceeding the corresponding overlying water column (t-stat = 5.51; p \u3c.0001). Aggregated data suggest these sediment control practices are not acting to reduce bacterial concentrations, but rather appear to be serving as reservoirs for viable E. coli and net sources of bacterial loading to receiving waters. Quantification of construction site bacterial runoff, potential basin-related bacterial contamination, and examination of site discharges will assist stormwater regulators and engineers in evaluating the efficacy of state construction permit standards and confirm whether site design practices are protective enough of receiving water quality. Results may also provide information to assess whether the present course of construction-related stormwater design and management is suitable or sustainable
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Wetland restoration in Oregon : issues, options, and recommendations
"This report is organized as follows. First, the
objectives and methods used are outlined. Background
information follows, including what is known about the
extent, past alterations, and condition of wetlands in
Oregon today; the status of wetland restoration in the U.S.
and in Oregon; definitions of important terms; the functions
of wetlands and their importance in restoration planning and
priority setting; and a general model for the role of
restoration in overall wetlands management. Next is the
slate of ecological, socioeconomic, and institutional
principles that should be followed throughout policy
formulation. This is followed by the heart of the report: a
three-tiered, function-based framework for wetland
restoration and priority setting in Oregon. Finally,
responsibilities and methods for implementing the planning
framework are outlined, primarily from an institutional
perspective. Several appendices provide additional
background and supporting information."--p.
Reductions in turbidity and Escherichia coli density using passive polymer treatment
Current research shows sediment basins may act as reservoirs for potentially harmful bacteria, including Escherichia coli (E. coli). E. coli preferentially attach to clay-sized particles and have been found in sediment basin outflows with high turbidity levels containing concentrations exceeding water quality standards recommended by the US Environmental Protection Agency. Since research shows E. coli preferentially attach to the clay fraction within sediment, it was hypothesized that a reduction in turbidity and TSS would create a corresponding reduction in bacterial density. Construction site sediment basin discharge was simulated to determine whether a sediment tube configuration using anionic polymer application could reduce E. coli densities. Based on prior research, reductions in turbidity and suspended sediment were maximized by applying 100 g of granular polyacrylamide (PAM) directly to each of five sediment tubes before simulated runoff events. PAM application successfully reduced turbidity and TSS by 96% and 92%, respectively. Discharge after the last sediment tube had an average turbidity of 80 NTU and TSS of 174 mg/L. For the low E. coli density range (5,000–10,000 MPN/100 mL), PAM application failed to create a reduction in bacterial density, but rather an increase in E. coli was observed with an average discharge of 25,226 MPN/100 mL. Within the high E. coli density range (100,000-200,000 MPN/100 mL), a 29% reduction was recorded with an average discharge of 135, 270 MPN/100 mL
Calico Creek Stabilization
2010 South Carolina Water Resource Conference. Informing strategic water planning to address natural resource, community and economic challenges
Is Stormwater Treated? A Survey of Awareness and Behaviors That May Impact Nonpoint Source Education
2010 S.C. Water Resources Conference - Science and Policy Challenges for a Sustainable Futur
Passive Polymer Application for Turbidity Reduction
2012 S.C. Water Resources Conference - Exploring Opportunities for Collaborative Water Research, Policy and Managemen
Bacteria in Construction Site Sediment Basins
2010 S.C. Water Resources Conference - Science and Policy Challenges for a Sustainable Futur
Cyberinfrastructure for Preservation of Stream and River Ecology
2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio
Medial open transversus abdominis plane (MOTAP) catheters for analgesia following open liver resection: study protocol for a randomized controlled trial
Background: The current standard for pain control following liver surgery is intravenous, patient-controlled analgesia (IV PCA) or epidural analgesia. We have developed a modification of a regional technique called medial open transversus abdominis plane (MOTAP) catheter analgesia. The MOTAP technique involves surgically placed catheters through the open surgical site into a plane between the internal oblique muscle and the transverse abdominis muscle superiorly. The objective of this trial is to assess the efficacy of this technique.
Methods/design: This protocol describes a multicentre, prospective, blinded, randomized controlled trial. One hundred and twenty patients scheduled for open liver resection through a subcostal incision will be enrolled. All patients will have two MOTAP catheters placed at the conclusion of surgery. Patients will be randomized to one of two parallel groups: experimental (local anaesthetic through MOTAP catheters) or placebo (normal saline through MOTAP catheters). Both groups will also receive IV PCA. The primary endpoint is mean cumulative postoperative opioid consumption over the first 2 postoperative days (48 hours). Secondary outcomes include pain intensity, patient functional outcomes, and the incidence of complications.
Discussion: This trial has been approved by the ethics boards at participating centres and is currently enrolling patients. Data collection will be completed by the end of 2014 with analysis mid-2015 and publication by the end of 2015.
Trial registration: The study is registered with http://clinicaltrials.gov (NCT01960049; 23 September 2013)This research is supported by the Innovation Fund of the Alternative Funding Plan from the Academic Health Sciences Centres of Ontario
Water Withdrawal Regulations Every Agricultural User in South Carolina Should Know
South Carolina has important regulations to protect and conserve its water resources. This article should aid producers in better understanding state water quantity regulations potentially impacting their operations and help them avoid possible penalties. Educational tools were included to assist users in understanding relevant regulations and for estimating water usage
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