The National Academies Press

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From page 132... ... B-2 interpreting the Results of Airport Water Monitoring Fact Sheet 1 Odor General Description Odors in stormwater or streams can be objectionable to the public as well as personnel working at an airport. The perception of odor can vary significantly by individual. Read the entire page →
From page 133... ... Field Conditions Fact Sheets B-3 recommended that field personnel assess the potential sources of these observations through sampling and analysis before drawing firm conclusions. • Rotten eggs or sulfur – A smell of rotten eggs indicates the presence of hydrogen sulfide, which is produced during the decay of organic matter in the presence of sulfate, due to sulfur-reducing bacteria. Read the entire page →
From page 134... ... B-4 interpreting the Results of Airport Water Monitoring Fact Sheet 2 Clarity/Turbidity/Solids General Description Clarity is often synonymous with transparency and represents the ability of light to be transmitted through the water. Low clarity in water, which is referred to as "turbidity," is an optical indication of the presence of colloidal or suspended solids in water that reduces the ability of light to pass through the water. Read the entire page →
From page 135... ... Field Conditions Fact Sheets B-5 other related parameters such as total suspended solids (TSS) and specific chemical compounds. Read the entire page →
From page 136... ... B-6 interpreting the Results of Airport Water Monitoring Fact Sheet 3 Foam General Description Foam in stormwater can be easily observed. Foam typically requires two components to form: surfactants and air. Read the entire page →
From page 137... ... Field Conditions Fact Sheets B-7 with a spill of a detergent or other stored material containing surfactants. Alternatively, foam observed at outfalls may be associated with naturally occurring surfactant sources in the receiving stream. Read the entire page →
From page 138... ... B-8 interpreting the Results of Airport Water Monitoring Fact Sheet 4 Color General Description As water is naturally colorless, the observation of color in water to be sampled is an indicator that pollutants may be present. Color in water is typically categorized by "apparent color" (immediate color observed) Read the entire page →
From page 139... ... Field Conditions Fact Sheets B-9 occurring) or the presence of oil, grease, or petroleum hydrocarbons. Read the entire page →
From page 140... ... B-10 interpreting the Results of Airport Water Monitoring also be associated with the release of a pollutant of that color, such as oil runoff from parking lots, and may be characterized in conjunction with observations of odor and sheen. Black may also be attributable to the presence of natural minerals such as manganese oxide. Read the entire page →
From page 141... ... Field Conditions Fact Sheets B-11 Fact Sheet 5 Sheen General Description Sheen is a visually observed field condition that may be noted on the surface of water within a receiving stream or conveyance system, or within a collected sample. A sheen is observed in the reflection of light off of a floating film on the water surface. Read the entire page →
From page 142... ... B-12 interpreting the Results of Airport Water Monitoring to the storm sewer system, or by an oil–water separator not being properly maintained. It may also be associated with a spill or leak of a petroleum product from tanks, drums, equipment, vehicles, or aircraft. Read the entire page →
From page 143... ... Field Conditions Fact Sheets B-13 Fact Sheet 6 Nuisance Microbial Biofilms General Description Microbial biofilms are complex ecosystems of micro-organisms bound together by a matrix of extracellular polymeric substances that are produced by algae and other micro-organisms (Mericas et al., 2014; Callow, 2000) Read the entire page →
From page 144... ... B-14 interpreting the Results of Airport Water Monitoring • Color • Texture • Ambient conditions A more detailed documentation of measured conditions associated with biofilm growth could include the following: • Analysis of water constituents • Classification of biofilm Location The most basic field observation to document is the location of microbial biofilm growth. The growth can be present on a number of surfaces at and near airports, including the following: • Storm sewers • Outfall pipes • Base of open channels • Structures supporting open channel or stream bed slopes (e.g., riprap, articulating block) Read the entire page →
From page 145... ... Field Conditions Fact Sheets B-15 Biofilm Structure/Texture Micro-organisms in biofilms are distinguished from planktonic micro-organisms by the presence of the extra polymeric substances (EPS) that bind the micro-organisms together in biofilms. Read the entire page →
From page 146... ... B-16 interpreting the Results of Airport Water Monitoring Biofilm management at airports is a significant challenge because of the high variability in both biofilm and ambient conditions. It is also a challenge because biofilms can appear in many locations. Read the entire page →
From page 147... ... Field Conditions Fact Sheets B-17 Fact Sheet 7 Toxicity General Description This fact sheet covers monitoring considerations for aquatic toxicity. Through requirements in the Clean Water Act, NPDES permits include narrative criteria that indicate that discharges to surface waters shall be free from substances in amounts toxic to humans or aquatic life. Read the entire page →
From page 148... ... B-18 interpreting the Results of Airport Water Monitoring receiving water body. Aquatic toxicity tests are either freshwater or marine and generally fall into one of two categories: 1. Read the entire page →
From page 149... ... Field Conditions Fact Sheets B-19 WET Monitoring Sample Timing and Type The sample type (grab, composite) , timing, and frequency require an understanding of the variation in flow rate and contaminant concentrations. Read the entire page →
From page 150... ... B-20 interpreting the Results of Airport Water Monitoring Key Steps in WET Analytical Testing Process An overall understanding of the WET analytical testing process at the laboratory can help the airport reduce the risk of non-representative test results and track potential sources of error after results have been received. At the laboratory, steps for performing toxicity tests involve (1) Read the entire page →
From page 151... ... Field Conditions Fact Sheets B-21 in Table B-3. Some of these WET test methods are used extensively, while others are used only infrequently due, in part, to limited organism availability or to limited regional applicability. Read the entire page →
From page 152... ... B-22 interpreting the Results of Airport Water Monitoring the endpoint is failure to fertilize or for embryos to develop, respectively, the endpoint is referred to as a 50% effect level (EC50 or median effective concentration) Read the entire page →
From page 153... ... Field Conditions Fact Sheets B-23 from the laboratory that the following conditions have been met and any deviations have been noted along with their effect on the acceptability of the test: 1. Samples have been held from 0°C to 6°C from the time of collection until used in the toxicity test, and holding times should not exceed 36 hours. Read the entire page →
From page 154... ... B-24 interpreting the Results of Airport Water Monitoring be demonstrated that the toxicity no longer occurs. The objective of the TRE is to determine those actions necessary to reduce the effluent's toxicity to acceptable levels. Read the entire page →
From page 155... ... Field Conditions Fact Sheets B-25 approaches for the identification of various chemical classes are discussed in detail in U.S. EPA's Phase II TIE manual (U.S. Read the entire page →
From page 156... ... B-26 interpreting the Results of Airport Water Monitoring Glossary of WET Terms Action limit: The limit on a control chart, which, if exceeded, requires corrective action to be taken. Action limits are usually placed at ± 3 standard deviations from the mean value. Read the entire page →
From page 157... ... Field Conditions Fact Sheets B-27 Median lethal concentration (LC50) : The concentration of a material in water that is estimated to kill 50% of the test organisms. Read the entire page →
From page 158... ... B-28 interpreting the Results of Airport Water Monitoring Standard: A solution of known and documented concentration, either a check or control standard, or a calibration standard that is used to prepare a calibration curve. Standard deviation: A statistic that describes the random variability in results of repeated measurements. Read the entire page →

From page 132...

... B-2 interpreting the Results of Airport Water Monitoring Fact Sheet 1 Odor General Description Odors in stormwater or streams can be objectionable to the public as well as personnel working at an airport. The perception of odor can vary significantly by individual.