Transcript Wells – The Basics

Michael Papay, REHS
Lee County Environmental Health
Private Wells
Septic Systems
(919) 718-4641
Private Water Supply Wells
Types of Wells (in Lee County)
• Dug
• Bored
• Drilled
Dug Well
• Literally “hand dug”
• Mineralogy from the soil
• Considered unsafe for drinking water
– Not protected from surface water intrusion
– No casing
– Rock-lined or un-lined walls
– Water source very shallow (near ground surface)
– Potential to transmit contaminants deeper
Bored Well
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20- to 24-inches wide
Shallow, max 90 ft. (generally 35-ish)
Concrete casing / Tile casing (grout?)
Mineralogy from soil (& weathered rock)
Often coliform + (= unsafe)
– Water source near ground surface
– Root intrusion between casing sections
– Potential to transmit contaminants deeper
Drilled Well
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Penetrates consolidated rock
Deep (100 – 400 feet, or more)
6-inch casing (steel or PVC)
Mineralogy from the rock that holds the water
Lee County Private Water Supply Well Program
• Permitting & Inspection
– New
– Repair
• Sampling
– New Wells
– Existing Wells
Sampling
• New Well Standard Kit
– Microbiological
– Inorganic
– Nitrates/Nitrites
• Individual Sample Types
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Microbiological
Inorganic
Nitrates/Nitrites
Pesticides
Petroleum
• VOCs
• Extractables
Microbiological
• Coliform
– Indicate the well is contaminated
– If these are present then nastier microbes might
be present
• Fecal Coliform
– From animal waste/poo
Inorganic Analysis
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Arsenic
Barium
Cadmium
Calcium
Chloride
Chromium
Copper
Fluoride
Iron
Lead
Magnesium
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Manganese
Mercury
Nitrate/Nitrite
pH
Selenium
Silver
Sodium
Sulfate
Total Alkalinity
Total Hardness
Zinc
Laws and Rules for Private Water Supply Wells
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40 CFR 141.2 (Definitions)
G.S. 87 Article 7 (N.C. Well Construction Act)
G.S. 130A Article 10 (N.C. Drinking Water Act)
15A NCAC 02C .0100 (Well Constr. Standards)
15A NCAC 02C .0300 (Permitting & Inspection)
15A NCAC 18C .0100 (Protection of Public
Water Supplies)