【正文】 TT3 Turbidity is a measure of the cloudiness of water. It is used to indicate water quality and filtration effectiveness (., whether diseasecausing organisms are present). Higher turbidity levels are often associated with higher levels of diseasecausing microorganisms such as viruses, parasites and some bacteria. These organisms can cause symptoms such as nausea, cramps, diarrhea, and associated headaches.Soil runoffViruses (enteric)zeroTT3 Gastrointestinal illness (., diarrhea, vomiting, cramps)Human and animal fecal wasteTop of pageDisinfection ByproductsContaminantMCLG1 (mg/L)2MCL or TT1 (mg/L)2Potential Health Effects from LongTerm Exposure Above the MCL (unless specified as shortterm)Sources of Contaminant in Drinking WaterBromatezeroIncreased risk of cancerByproduct of drinking water disinfectionChloriteAnemia。 it is used to indicate whether other potentially harmful bacteria may be present5Coliforms are naturally present in the environment。s Disease, a type of pneumoniaFound naturally in water。 For more information, read Secondary Drinking Water Regulations: Guidance for Nuisance Chemicals. List of National Secondary Drinking Water RegulationsContaminantSecondary StandardAluminum to mg/LChloride250 mg/LColor15 (color units)Copper mg/LCorrosivitynoncorrosiveFluoride mg/LFoaming Agents mg/LIron mg/LManganese mg/LOdor3 threshold odor numberpHSilver mg/LSulfate250 mg/LTotal Dissolved Solids500 mg/LZinc5 mg/LMicroorganismsContaminantMCLG1 (mg/L)2MCL or TT1 (mg/L)2Potential Health Effects from LongTerm Exposure Above the MCL (unless specified as shortterm)Sources of Contaminant in Drinking WaterCryptosporidium zeroTT 3 Gastrointestinal illness (., diarrhea, vomiting, cramps)Human and animal fecal wasteGiardia lambliazeroTT3 Gastrointestinal illness (., diarrhea, vomiting, cramps)Human and animal fecal wasteHeterotrophic plate countn/aTT3 HPC has no health effects。(b) The standard is attained when the expected number of days per calendar year with maximum hourly average concentrations above ppm is 1.(11) (a) Final rule signed June 2, 2010. To attain this standard, the 3year average of the 99th percentile of the daily maximum 1hour average at each monitor within an area must not exceed 75 ppb.National Secondary Drinking Water RegulationsNational Secondary Drinking Water Regulations (NSDWRs or secondary standards) are nonenforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA remends secondary standards to water systems but does not require systems to ply. However, states may choose to adopt them as enforceable standards.(c) EPA is in the process of reconsidering these standards (set in March 2008).(10) (a) EPA revoked the 1hour ozone standard in all areas, although some areas have continuing obligations under that standard (antibacksliding).(b) The 1997 standard—and the implementation rules for that standard—will remain in place for implementation purposes as EPA undertakes rulemaking to address the transition from the 1997 ozone standard to the 2008 ozone standard. (effective May 27, 2008) (9) (a) To attain this standard, the 3year average of the fourthhighest daily maximum 8hour average ozone concentrations measured at each monitor within an area over each year must not exceed ppm. g/m3.(7) To attain this standard, the 3year average of the 98th percentile of 24hour concentrations at each populationoriented monitor within an area must not exceed 35 181。g/m3Annual (6) (Arithmetic Average)Same as Primary35 181。g/m3Quarterly AverageSame as PrimaryNitrogen Dioxide53 ppb (3)Annual (Arithmetic Average)Same as Primary100 ppb1hour (4) None Particulate Matter (PM10)150 181。Primary StandardsSecondary StandardsPollutantLevelAveraging TimeLevelAveraging TimeCarbon Monoxide9 ppm (10 mg/m3) 8hour (1) None 35 ppm (40 mg/m3)1hour (1)Lead 181。National Ambient Air Quality Standards (NAAQS)The Clean Air Act, which was last amended in 1990, requires EPA to set National Ambient Air Quality Standards (40 CFR part 50) for pollutants considered harmful to public health and the environment. The Clean Air Act established two types of national air quality standards. Primary standards set limits to protect public health, including the health of sensitive populations such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings.The EPA Office of Air Quality Planning and Standards (OAQPS) has set National Am