Characterization of Stormwater Runoff from North Carolina Bridges and Determination of Effects on Selected Receiving Waters

2012 ◽  
Vol 2309 (1) ◽  
pp. 178-199 ◽  
Author(s):  
Chad Wagner ◽  
Sharon Fitzgerald ◽  
Matthew Lauffer

The North Carolina Department of Transportation and the U.S. Geological Survey collaborated on a study to better understand the effects of stormwater runoff from bridges on receiving waters. The following tasks were performed: (a) characterizing the quality and quantity of stormwater runoff from a representative selection of bridges in North Carolina, (b) measuring the quality of stream water upstream of selected bridges to compare constituent concentrations and loads in bridge deck stormwater with those in the stream, (c) determining whether the chemistry of bed sediment upstream and downstream of selected bridges differed substantially according to the presence or absence of a best management practice for bridge runoff, and (d) estimating the rate at which bridge deck runoff mixed with the receiving stream. The investigation measured bridge deck runoff from 15 bridges for 12 to 15 storms, the quality of stream water for base flow and storm conditions at four of the bridge deck sites, and the chemistry of stream bed sediment upstream and downstream of 30 bridges across North Carolina. Runoff and stream samples were analyzed for a wide range of constituents, including dissolved and total recoverable metals and nutrients, major ions, total suspended solids, suspended sediment, oil and grease, petroleum hydrocarbons, and semi-volatile organic compounds. For 64% of comparisons, concentrations in bridge deck runoff were no different or were less than those measured in receiving waters, and the maximum concentrations of constituents in the bridge deck runoff were rapidly reduced to the ambient stream concentrations, generally within 50 ft downstream of the bridge.

2011 ◽  
pp. i-95
Author(s):  
Chad R. Wagner ◽  
Sharon A. Fitzgerald ◽  
Roy D. Sherrell ◽  
Douglas A. Harned ◽  
Erik L. Staub ◽  
...  

2013 ◽  
Vol 10 (8) ◽  
pp. 12849-12885
Author(s):  
H. Borg ◽  
M. Sundbom

Abstract. The water chemistry of streams and precipitation in the province of Jämtland, northern Sweden has been monitored since the 1980s to study long-term trends, occurrence of acid episodes, and effects of liming. The acidity and sulphur in precipitation increased in the 1970s, followed by a loss of ANC and low pH in the streams. Sulphur deposition begun to decrease in the 1980s, until approximately 2000, after which the decrease levelled out. The stream water sulphate followed the precipitation trend but decreased more slowly and since the late 1990s a subtle increase was observed. The sulphate concentrations in the snow have generally been higher than or equal to the stream sulphate levels. Since 2005, stream sulphate has sometimes exceeded snow sulphate, indicating desorption of stored soil sulphate, possibly because of climate related changes in run-off routes through the soil profiles, following shorter periods of frost. Up to 2000, TOC increased by approximately 0.1 mg L−1 yr−1. The mean trends in sulphate and TOC from approximately 1990 until today are generally opposite. Acidic episodes with pH 4.0 at flow peaks occurred frequently in the unlimed streams, despite relatively well buffered waters at base flow. To evaluate the main causes for the loss of ANC, the changes in major ions during high flow were calculated. The most important contribution resulted from dilution of base cations, with contribution from organic anions. Sulphate also had some influence, as it was somewhat enriched or only slightly diluted during high flow. Wetland liming started in 1985 after which the earlier observed extreme peak values of Fe, Mn and Al, did not return. The studied area is remote from emission sources in Europe, but the critical load of acidity is still exceeded. The long-term recovery observed in the unlimed streams is thus slow, and severe acidic episodes still occur.


2013 ◽  
Vol 15 (1) ◽  
pp. 85-92 ◽  

Nowadays, it is a common ascertainment that stormwater runoff in the urban and interurban road network consist non-point source pollution which contributes to the degrading of the quality of water of ground and surface water bodies. Taking into account the fact that water pollution has impacts to people and also to flora and fauna, the need to take measures in order to confront this environmental problem becomes inevitable. The adverse impacts of the stormwater runoff can be minimized with structural and non-structural Best Management Practices (BMPs) or with a combination of them. Within the content of the present paper the following are included: a) the investigation and presentation of the receiving waters pollution issues from the highway road network stormwater runoff together with the European transport policy concerning the development of an integrated highway road network, b) the examination of the respective pollutant generation and characteristics, c) the presentation of their impacts, d) the examination of the measures (structural and nonstructural BMPs), e) the presentation of the “first flush” phenomenon, f) The presentation of the existing legislation in the EU with emphasis in the E.U. Directive 2000/60/EC as well as the presentation of the relevant existing environmental legislation in Greece, including also the presentation of the way the Highway Guidelines actually deal with the specific problem.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


2019 ◽  
pp. 462-471
Author(s):  
Lyudmila Shirokova

The historical polyethnicity of the Slovak society and the connected problems of the interrelations of cultures, ethics, interpersonal relations, are reflected in the works of modern Slovak prose. They are represented most clearly in the novels of middle generation writers P. Rankov, S. Lavrík, P. Krištúfek. They dwell upon the dramatical events of the 20 th century. They cover wide range problems, from the fruitful coexistence of various ethnic groups and their representatives to national contradictions and racial repressions. The artistic quality of the mentioned works, their composition, the way of narrating, the type of the main character, can be highly evaluated. For example, in a novel by P. Rankov the plot, in spite of its linearity, is a chain of episodes in the span of 30 years from the life of the main characters. It reflects not only their fates, but also the historical and political changes of the world they live in. The main female character of a S. Lavrík ’s novel narrates about everyday life and tragedies in the lives of the dwellers of a Slovak town in the Slovak Republic during the war. P. Krištúfek in his novel focuses on several decades from the life of a Slovak-Jewish family and dwellers of a Slovak provincial society with types and relations specific for this milieu.


Author(s):  
Katherine V. Whittington

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.


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