Laboratory chronic toxicity tests with plankton, benthos, and fish early life stages were conducted with total dissolved solids (TDS) at an ionic composition specific to Snap Lake (NWT, Canada), which receives treated effluent from the Snap Lake Diamond Mine. Snap Lake TDS composition has remained consistent from 2007 to 2014 and is expected to remain unchanged through life of mine: chloride (45‐47%), calcium (20‐21%), sodium (10‐11%), sulfate (9%); carbonate (5‐7%), nitrate (4%), magnesium (2‐3%), and minor contributions from potassium and fluoride. TDS concentrations that resulted in negligible effects (i.e., 10 or 20% effect concentrations) to taxa representative of resident biota ranged from >1,100 to >2,200 mg/L with the exception of a 21% effect concentration of 990 mg/L for one of two early life stage fish dry fertilization tests (wet fertilization results were >1,480 mg/L). A conservative, site‐specific, chronic effects benchmark for Snap Lake TDS of 1,000 mg/L was derived, below the lowest negligible effect concentration for the most sensitive resident taxon tested, the cladoceran, D. magna (>1,100 mg/L). Cladocerans typically only comprise a few percent of the zooplankton community and biomass in Snap Lake; other plankton effect concentrations ranged from >1,330 to >1,510 mg/L. Chironomids, representative of the lake benthos, were not affected by >1,380 mg/L TDS. Early life stage tests with three fish species resulted in 10 to 20% effect concentrations ranging from >1,410 to >2,200 mg/L. The testing undertaken is generally applicable to northern freshwaters and the concept can readily be adapted to other freshwaters either for TDS where ionic composition does not change or for major ionic components where TDS composition does change. This article is protected by copyright. All rights reserved
Abstract
Due to pressure of human activity, urbanization and industrialization, the groundwater sources are degraded gradually; therefore pure, safe, healthy and odorless drinking water is a matter of deep concern. There are many pollutants in groundwater due to seepage viz. organic and inorganic pollutants, heavy metals, pesticides, fluorides etc. In Rajasthan state, all 32 districts are affected with high fluoride concentration in groundwater and among these Jaipur ranks second. The drinking water samples...
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LuminoTox, a new easy to use tool for
toxicity assessment, has been tested
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LuminoTox proved effective for rapid
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both treated and untreated effluents,
including municipal wastewaters,
leachates from landfill sites, pulp and
paper mill effluents and mining
industry effluents. It was also found
to be an effective means of assessing...
Early life-stage toxicity tests with copper and pentachlorophenol (PCP) were conducted with two species listed under the United States Endangered Species Act (the endangered fountain darter, Etheostoma fonticola, and the threatened spotfin chub, Cyprinella monacha) and two commonly tested species (fathead minnow, Pimephales promelas, and rainbow trout, Oncorhynchus mykiss). Results were compared using lowest–observed effect concentrations (LOECs) based on statistical hypothesis tests and by point estimates...
High levels of fluoride (beyond 1.5 ppm) in ground water as source of drinking water are common in many parts of Andhra Pradesh, India, causing fluorosis. The study carried out in endemic Nalgonda District, Andhra Pradesh, has indicated that the fluoride-rich ground water present in the wells located down stream and close to the surface water bodies is getting diluted by the low-fluoride surface water. Encouraged by this result, check dams were constructed upstream of the identified marginally high fluoride...
Manufacturers of chemical products and products that contain significant chemical components need to be aware of subtle but important changes in the “persons required to test” provisions of Section 4 of the Toxic Substances Control Act (TSCA). Historically, those persons have included chemical manufacturers, processors, or those who intend to process or manufacture a Section 4 test rule substance. In the recent past, the United States Environmental Protection Agency (EPA) has sought to expand the class of...
Abstract
Increasing dependence on chemicals and rapid developments in chemical technology have practically triggered the growth of chemical industries in India. Globally, Basel convention guidelines are available for transboundary movement of hazardous wastes. However, at the national levels, health damage, resources losses and ecological impairment due to hazardous wastes indiscriminate discharges are a reality. In India, there are over 16,000 units of big and small Pharmaceutical industries alone. Quantities...
1.1 Scope and Objectives
A small number of viable options are presently available for the bleaching of wood pulp (delignification and brightening) during the manufacture of pulp and paper. The use of chlorine dioxide (ClO2) in the bleaching process has largely superceded the earlier use of Cl2, or elemental chlorine, in the majority of North American pulp mills: It was discovered over a decade ago that the previous widespread use of Cl2 contributed to the production and subsequent release to the environment of...
From the beginning of World War II until the 1970s, the site that is now the Naval Surface Warfare Center in Crane, Indiana (NSWC-Crane) was the home of a major bomb manufacturing operation. Explosive compounds such as TNT, Royal Demolition Explosives (RDX) and Her Majesty’s Explosive (HMX) were handled loose and drifted through air vents. Often, the material settled on the roofs of buildings, which were hosed off. The compounds contaminated the soil so that five decades later, the tainted earth still has a...
Background
For the last twelve months Richard Powell has been using water based `base coat` paints in his smash repair business at Woolloongabba. These paints use water, instead of solvent, as the carrier for the basic paint constituents, and do not release any harmful vapours to the atmosphere.
Richard has been in the smash repair business for more than twenty five years and established Brisbane Motor Bodies Pty Ltd (BMB) at Woolloongabba about eleven years ago. BMB is a medium sized business operating with...
It may be necessary to know other subsurface information to remediate inorganics in ground water, surface water, and leachate. Treatability studies are usually necessary to ensure that the contaminated ground water can be treated effectively at the design flow. A subsurface geologic characterization would be particularly important to characterize the effects of adsorption and other processes of attenuation. Ground water models are also often needed to predict flow characteristics, changes in contaminant mixes and...
Introduction
The Clifton Water District (Colorado) covers roughly 20 square miles stretching east of Grand Junction to Palisade, and extending south from I-70 to the Colorado River. The District has approximately 7,400 service connections serving a population of 30,000. Utilizing the Colorado River as its primary source, the District`s Charles A. Strain Water Treatment Plant has a capacity of 12 million gallons per day (mgd). Conventional water treatment processes are employed including presedimentation, coagulati...
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