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Use the Home*A*Syst self-assessment tool to evaluate potential pollutants and protect your well water quality. Identify sources, minimize contamination, and maximize filtration and purification.
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Well Water Quality Home*A*Syst& UGA Water Testing Frank Henning, UGA Watershed Extension Agent
Potential Pollutants ex) Cleaning products, Gasoline, Oil, Pesticides, fertilizers, animal waste, septic systems… Easier to exclude pollutants than clean up!!!!
Minimize contamination Maximize filtration/purification
Safe Drinking Water Who is protecting drinking water supplies? Who is testing for contamination?
Using Home*A*Syst to Protect Your Water Supply Self Assessment: - a or b = few problems - c or d = potential problems - c or d Consider making changes to protect drinking water *Adapted from National Home*A*Syst Program & NCSU Home*A*Syst Publication
1. Where is your well located? • Uphill from all pollution sources. • No surface runoff reaches well. • Surface water flows away from well. b. Uphill from most pollution sources. No surface water runoff reaches the well if drainage is working correctly. c. Downhill from many pollution sources, or one hazardous source. Some surface runoff may reach well. d. Settling or depressions around casing. Surface water runoff collects near well, or do not know.
2. Which best describes your well? 500 feet - Landfill 100 feet – Sewage , Animal waste, Chemicals and other potential contaminants. 50 feet – Building foundations, surface water • All separation distances are greater than minimum requirements. • Separation distances are at least ¾ the minimum • Separation distances are a least ½ the minimum • Some separation distances are less than ½ the minimum, or do not know.
3. How well does soil filter out pollutants? • Fine textured soils (clay loam, silty clay) • Medium textured soils (silt, silt loam) • Medium or coarse textured soils with low organic matter • Coarse textured soils (sands, sandy loam), or do not know.
4. How quickly does water reach your well? • Water Table or fractured bedrock deeper than 50 feet. • Water table or fractured bedrock deeper than 25 feet. • Water table or fractured bedrock deeper than 10 feet • Water table or fractured bedrock shallower than 10 feet, or do no know.
5.What is the condition of your well casing? • No holes or cracks. Cap tightly secured. Screen vented • No defects visible. Well is vented, but not screened. • No holes or cracks visible. Cap easily removed. • Holes or cracks visible. Cap loose or missing. Can hear water running; or do no know.
6. Are casing and grout deep enough? • Which best describes the casing and grouting of your well? • Cased and grouted to required depth. • Cased and grouted below water table of well • Cased, but not grouted. • No casing. No grout; or do not know.
7. Is the well protected at the ground surface? Which best describes your wellhead? • Casing extends more than 12 inches above surface and concrete pad extends 2 feet in all directions • Casing above ground level and concrete pad 1 to 2 feet in all directions • Casing above ground level and no concrete pad. • Casing below ground level or in pit or basement and no concrete pad; or do not know
8. How old is your well? • Less than 15 years old • 15 to 30 years old • 30 to 60 years old • More than 60 years old; • or do not know
9. Was your well drilled or dug? • Drilled well • Jetted or bored • Driven (sand point) • Dug; or do not know.
Bored Large diameter (2 ft or larger) Shallow (uaually less than 60 ft) Vulnerable to surface influences Bacteria Chemicals Drilled Small diameter (usually 6 in) Deep (usually greater than 200 ft) Less susceptible to surface influences Types of Wells
10. Are you preventing backflow? • Check valves are installed on all faucets with hose connections and there are no cross-connections between water supplies. • Check valves are installed on some faucets with hose connections, or one check valve at well pump • No check valves installed. Air gap maintained. • No check valves installed. Air gap not maintained. Cross connections between water supplies; or do no know.
11. Do you have any unused wells? • No unused, unsealed wells. • Unused wells sealed and filled. • Unused well on property more than 100 feet from supply well. Not capped or filled. • Unused well less than 100 feet from supply well. Not capped or filled; or do not know.
12. Has your well been tested recently? • Consistent, satisfactory water quality. Bacteria, nitrate, and other tests meet standards. • Occasional deviation from standards with bacteria, nitrate, and other tests. • Bacteria, nitrate and other tests often do not meet standards. • No water tests done; or water discolored after rainstorms, or noticeable changes in color, clarity, odor or taste; or do not know.
Indicator Organism Concept • Correlated to the presence of pathogens • Population large enough to isolate in small water samples (100 mL) • Rapid • Inexpensive • Safety, not culturing pathogens
total coliform fecal coliform E. coli Standard Bacteria Test • Total coliform • Escherichia coli Cost: ~$25
Pathogen Problems • Numerous water borne pathogens • Individual pathogen numbers may be too low to detect in a reasonable sized water sample • Isolation and detection of some pathogens can take several days, weeks, or months • Absence of one particular pathogen does not rule out the presence of another
These are the elements and compounds that can cause adverse health effects when above the maximum contaminant level (MCL) set by the EPA. Cadmium (0.005 ppm) Chromium (0.005 ppm) Copper (1.3 ppm) Fluoride (4.0 ppm) Nitrate-N (10 ppm) Primary Standard
These are not generally considered threats to health, but cause nuisance problems such as staining, bad tastes and odors when above threshold levels. Aluminum (0.2 ppm) Chloride (250 ppm) Copper (1.0 ppm) Fluoride (2.0 ppm) Iron (0.3 ppm) Manganese (0.05 ppm) Sulfate (250 ppm) Total Dissolved Solids (500 ppm) Secondary Standards
pH Hardness Aluminum Boron Cadmium Calcium Chromium Copper Iron Magnesium Manganese Molybdenum Phosphorus Sodium Zinc Basic Water Test~$15
Alkalinity Conductivity Saturation Index Total Dissolved Solids Silica Nitrate-N Chloride Fluoride Sulfate Phosphate Expanded Water Test Packagebasic + more ($48)
When to Recommend the Expanded Test • When client hasn’t previously done this test package • When client is having a problem • Blue green staining • Bitter tasting water • Numerous leaks • Mineral deposits • Salty tasting water • Muddy water • Etc. • When a water treatment system is being considered
Hardness (basic test)units: mg CaCO3/L (ppm) • Sum of the calcium (Ca) and magnesium (Mg) • Expressed as mg CaCO3/L (ppm) • Usually from the alkalinity or dissolved limestone • However, can be from other non-alkalinity minerals like gypsum (CaSO4 ) • Compare Hardness and Alkalinity
Alkalinity (expanded test)units: mg CaCO3/L (ppm) • Capacity to neutralize acid and can consist of: • Bicarbonate • Carbonate • Hydroxides • Silicates • Borates • Phosphates • Bicarbonate form in most natural water of Georgia and derived from limestone (CaCO3 and MgCO3)
Hardness vs. Alkalinity • Hardness = Alkalinity • Hardness is from the calcium or magnesium carbonates that account for the alkalinity • Hardness > Alkalinity • There are sources of Ca and Mg that are not from the carbonate alkalinity such as other neutral salts of Ca or Mg like gypsum (CaSO4) • Hardness < Alkalinity • There are sources of alkalinity that are not from Ca or Mg carbonates such as hydroxides or sodium carbonates
Corrosive Reduces the lifetime of the pump and plumbing Leaks Toxic metals can be leached from plumbing Stains on fixtures Metallic taste Scaling Fills hot water heaters with solids Causes blockages in plumbing Reduces flow Spots on glassware, utensils, and dishes Corrosive, Scalingor Balanced?
ConductivitySeimans (S)/cm = mhos/cm • Ability to conduct electricity • Increases proportional to the dissolved ionic solids • Inorganic compounds are good conductors but organic compounds are poor conductors • Levels • Distilled water: 0.3 to 5 S/cm • Drinking water: 50 to 1500 S/cm • Sea water: 64,000 S/cm • Conductivity (S/cm) X 0.55 = estimation of total dissolved solids (ppm)
Total Dissolved Solidsmg/L (ppm) • Residue remaining after filtered water is dried • If primarily inorganic salts then closely related to conductivity • Exceptions to this would be the “Blackwaters” that are high in organic compounds like tannin • Levels • Distilled water: 0.2 to 3 ppm • Drinking water: 28 to 825 ppm • Sea water: 35,000 ppm
Background Information • The expanded test package is also good for developing a history of background information, which is useful for tracking changes in water quality due to: • Deterioration of the well casing • Saltwater intrusion into the aquifer • Treatment system efficiency • Development in the watershed • Can fall back to the Basic (W1) package when the parameter or parameters of interest have been identified by the Expanded (W2) package and these are in the Basic package.
