Water Sampling and Testing Procedures: Sources and effects of chemical contaminants in water testing

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1 Water Sampling and Testing Procedures: Sources and effects of chemical contaminants in water testing Raymon Shange, PhD Tuskegee University Agricultural and Environmental Sciences Carver Integrative Sustainability Center

3 Water Quality Regulation EPA regulates public water systems; it does not have the authority to regulate private drinking water wells. Groundwater supplies are not subject to EPA standards, although some state and local governments do set rules to protect users of these wells.

4 Water Quality Regulation Unlike public drinking water systems serving many people, they do not have experts regularly checking the water s source and its quality before it is sent to the tap. Users must take special precautions to ensure the protection and maintenance of their drinking water supplies. Irrigation water quality is a determining factor in many food safety certifications.

5 Water Quality Laws Two major laws on water: 1. Clean Water Act Goal: To restore and maintain chemical, physical and biological integrity of the surface waters of the United States. Ultimate Goal: To make all surface waters of the U.S. swimmable and fishable

6 Safe Drinking Water Act (SDWA) Goals: To protect Drinking Water Mandates the establishment of uniform standards for drinking water quality Provides a system for regulating underground injection of wastes and other substances that could contaminate underground water sources.

7 Safe Drinking Water Act (SDWA) Drinking Water Standards 1. Primary Standards» The primary standards are set for contaminants deemed to pose a threat to human health and also to the environment.» The maximum contaminant level (MCL) set for primary contaminants are enforceable under the law.» MCL for nitrate is 10 ppm, Pb is 15 ppb

8 Safe Drinking Water Act (SDWA) 2. Secondary Standards Secondary Standards are only advisory and nor enforceable by federal government.» Normally concern physical characteristics which are not health hazards» Set Maximum Contaminant Levels consistent for the protection of the public

9 Contaminants of Well Water- Standard Water Hardness, ph, Alkalinity, Corrositivity Natural properties of the source water or surface water intrusion/system corrosion and staining of toilet, bathtub, or sinks. Formation of scale (whitecolored hard water deposits) on plumbing fixtures. Water softners/salts can be used for cation exchange

10 Nutrients in Groundwater Leaching and runoff are the main processes by which chemicals are carried into lakes, streams, canals, wetlands or groundwater. Surface runoff is the portion of rainfall or irrigation that is neither absorbed nor accumulated by the soils, but runs down the slope. Along with runoff water, any dissolved chemical or chemical attached to sediment particles can be carried off site, subsequently reaching the nearest water body.

11 Nutrients in Groundwater Leaching is the process by which water moves vertically down through the soil profile and reaches the groundwater. Sandy surface soils have limited ability to adsorb chemical constituents, which promotes movement down the profile. Due to geology, chemical-laden water can move upward through freshwater springs, causing eutrophication of surface water bodies.

13 Nitrates in Groundwater Nitrates/Nitrites May occur naturally, but man-made sources include areas of intensive agriculture (runoff from fertilizer use), CAFOs, landfills, dumps, sewage and leaking septic tanks Pose human health risk in forms of blue baby syndrome, N-nitrosoamines, pesticide coupling.

15 Nitrates in Groundwater Nitrate in ground water generally follows the risk map. Ground-water nitrate data collected by the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program were analyzed to verify the four risk groups shown on the national map.

16 Nitrates in Groundwater Aquifer vulnerability depends on soil-drainage characteristics and the extent of cropland versus woodland in agricultural areas. Areas with a high risk of ground-water contamination by nitrate generally have high nitrogen loading or high population density, well-drained soils, and less extensive woodland relative to cropland.

17 Nitrates in Groundwater The national risk map indicates contamination potential, but does not show actual nitrate contamination of ground water. Water-quality testing is necessary to determine actual nitrate concentration. Compared with public-supply wells, most privately owned wells are not routinely monitored for water quality.

18 Nitrates in Groundwater Nitrate concentration in ground water generally increases with higher nitrogen input and higher aquifer vulnerability. Median nitrate concentration and percent of wells from which water exceeds the EPA drinking-water standard for nitrate are highest in areas with high nitrogen input and high aquifer vulnerability.

20 Phosphates in Groundwater Phosphorus is an essential element for plant growth and agricultural productivity. Fertilizer commonly supplies the crop phosphorus requirement or replenishes P removed from a harvested crop biomass. Sometimes fertilization occurs in excess of the crop requirement determined by a calibrated soil test. Over the long term, this practice will increase soil P accumulation, the risk of off-site movement, and leaching in sandy-textured soils.

21 Phosphates in Groundwater Animal agriculture also contributes to increased buildup of phosphorus in soils. Intensive confined livestock production areas or Confined Animal Feeding Operations (CAFOs) accumulate large amounts of both solid and liquid manure, which through land application are used as nutrient sources for crop production.

22 Other Inorganic Pollutants Hydrogen Sulfide gas Surface water intrusion creates a favorable environment for anaerobic bacteria, supplying decaying vegetation Water has rotten egg smell

23 Other Inorganic Pollutants Iron Bacteria/Iron Naturally occurring but more likely to be present in corroding systems where iron source is high/ Red or brown staining; slimy, stringy brown growth in toilet; low water pressure

24 Other Inorganic Pollutants Arsenic To a degree, naturally occurring Runoff from orchards, industrial sources (e.g., electronics production, glass), waste sites or treated wood sites

25 Other Inorganic Pollutants Copper Naturally occurring, or caused by system corrosion Blue or green stains on fixtures and laundry Lead Naturally occurring or caused by system corrosion Older homes with lead plumbing or solder; possibly in homes located near historical highways (leaded gasoline run-off pre-1980s), industrial areas (battery production), landfills, agriculture, or gasoline storage (above or below ground).

26 Other Inorganic Pollutants Total Dissolved Solids (TDS) Surface water intrusion in areas of intensive agriculture, livestock, CAFOsii, construction, development, flooding or leaking septic tanks. Water may be cloudy, taste salty or gritty; recurring gastrointestinal problems

27 Possible Treatment Options Distillation Reverse Osmosis Ion Exchange

28 Organic Pollutants

29 Water Testing through TU Water Quality Program Contact local County Agent Collect water sample Send to TU WQP Receive prompt results & call to speak about results Suggested 2x yearly

30 Contact Info Raymon Shange

Water Quality Knowledge to Go Purdue Extension

WQ-4 Water Quality Knowledge to Go Purdue Extension Why & How to Test Home Water Supplies Jane Frankenberger, Department of Agricultural and Biological Engineering Cheri Janssen, Department of Agronomy