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

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.

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.

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

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.

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

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

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 (white-

colored hard water deposits) on plumbing fixtures.

• Water softners/salts can be used for cation

exchange

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.

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.

• http://www.bigberkeywaterfilters.com/wp/wp-content/uploads/2010/06/karst-contamination1.jpg

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.

• http://water.usgs.gov/nawqa/nutrients/pubs/wcp_v39_no12/

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.

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.

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.

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.

http://sci.waikato.ac.nz/farm/content/nutrientcycling.html

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.

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.

Other Inorganic Pollutants

• Hydrogen Sulfide gas

• Surface water intrusion creates a favorable

environment for anaerobic bacteria, supplying

decaying vegetation

• Water has rotten egg smell

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

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

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).

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

Possible Treatment Options

• Distillation

• Reverse Osmosis

• Ion Exchange

Organic Pollutants

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

Contact Info

Raymon Shange

334-724-4967

rshange2946@mytu.tuskegee.edu