Category: Industrial Wastewater Air Pollution and Solid And Hazardous Wastes
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Secondary Devices
Secondary devices are used in conjunction with primary devices to determine the actual flow passing the measuring point. Typically, secondary devices measure the depth of water in the primary device and convert the depth measurement to a corresponding flow, using established mathematical formulas. The output of the secondary device is generally transmitted to a recorder…
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Flow Measurements
Pollutant limits in the industrial user’s permit are often expressed in terms of mass loadings to an industrial facility or a POTW (e.g. categorical standards for conventional pollutants, organics, metals, microorganisms, etc.). To determine a mass loading, it is necessary to obtain and record accurate flow data. This section briefly describes the types of devices…
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Application of Toxicity Test Results
Water quality criteria ensure protection of designated uses by including magnitude (quantity of toxicant allowable), duration (period of time over which instream concentration is averaged), and frequency (how often criteria can be exceeded without unacceptable receiving water ecological community impacts). Contemporary water quality criteria are designed to protect against short‐term (acute) effects through use of…
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Toxicity Testing and Evaluation of Toxicity Test Results
Ecological toxicity tests are classified according to duration (short‐term, intermediate, and/or long‐term), method of adding test solutions (static, recirculation, renewal, or flow‐through), and (to satisfy permit requirements for a proposed pollutant discharge elimination system, and to determine mixing zones, etc.). Detailed contemporary testing protocols are summarized in the regulatory literature (USEPA 1985b, c, 1988, 1989). A number of terms…
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Whole Effluent Toxicity Testing
Introduction For selected industrial wastewater treatment plants (WWTPs), whole effluent biological testing is required under their NPDES permit. Whole effluent toxicity (WET), also referred as biomonitoring, is the toxicity of an effluent sample measured directly with a toxicity test in order to assess the total toxic effect of all pollutants. WET testing is necessary because…
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Sample Identification and Labeling
Each sample must be accurately and completely identified. At the time a sample is collected, a waterproof, gummed label or a waterproof tag that is able to withstand field conditions should be attached to the sample container. This label and/or tag is necessary to prevent any misidentification of samples, since it provides the laboratory with…
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Sample Documentation
Documentation is an integral part of any pretreatment program. The validity of the samples collected and the data obtained both in the field (e.g. pH and flow) and in the laboratory (i.e. chemical analyses) is ensured through documentation and record keeping. All the information documented must be complete and accurate. Failure to maintain records and…
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Continuous Monitoring
Continuous monitoring is another option for a limited number of parameters such as pH, temperature, dissolved oxygen (DO), conductivity, and TOC. Reliability, accuracy, and cost vary with the parameter. Continuous monitoring can be expensive, so continuous monitoring will usually only be an appropriate requirement for the most significant dischargers with variable effluent. The environmental significance…
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Grab Samples
A grab sample is an individual sample collected over a period of time not to exceed 15 minutes. Grab samples are usually taken manually, and the sample volume depends on the number of analyses to be performed. The sampler must make sure that sufficient volume of sample is taken to conduct all necessary analytical procedures, including…
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Type of Sample
There are two basic types of samples: grab samples and composite samples. The type of sampling that will be undertaken at the industrial user must be understood clearly and should be outlined in the facility’s Sampling and Quality Assurance Plan. It is very important that the facility establish specific procedures for collecting grab and/or composite…