Categorizing Hardness: (divide by 17.2 to get grains per gallon)
Chlorine Generator — By passing a current through brine water chlorine gas is emitted. In the case of a chlorine generator within a water conditioner this chlorine gas can be used to add chlorine and chlorine gas to both sterilize and oxidize the media during a regeneration cycle. Water PH is raised during this process.
Hydrogen sulphide gas is the source of the foul "rotten egg" smell and taste. Produced by natural decomposition of underground organic deposits and the action of sulfate reducing bacteria, Hydrogen Sulphide is highly corrosive and can cause damage to well casings, pumps and plumbing fixtures. Hydrogen Sulphide gas is easily detected with your nose. You can smell it in amounts so small that standard tests won't find it.
Sulfur-reducing bacteria, which use sulfur as an energy source, are the primary producers of large quantities of Hydrogen Sulphide. These bacteria chemically change natural sulfates in water to Hydrogen Sulphide. Sulfur-reducing bacteria are anaerobic and live in oxygen-deficient environments such as deep wells, plumbing systems, water softeners and water heaters.
Hydrogen Sulphide often is present in wells drilled in shale or sandstone, or near coal or peat deposits or oil fields. Occasionally, a hot water heater is a source of Hydrogen Sulphide odor. The magnesium corrosion control rod present in many hot water heaters can chemically reduce naturally occurring sulfates to Hydrogen Sulphide. If Hydrogen Sulphide odor is associated primarily with the hot water system, a hot water heater modification may reduce the odor. Replacing the water heater's magnesium corrosion control rod with one made of aluminum or another metal may improve the situation.
A nuisance associated with Hydrogen Sulphide includes its corrosiveness to metals such as iron, steel, copper and brass. It can tarnish silverware and discolor copper and brass utensils. Hydrogen Sulphide also can cause yellow or black stains on kitchen and bathroom fixtures. Coffee, tea and other beverages made with water containing Hydrogen Sulphide may be discolored and the appearance and taste of cooked foods can be affected.
Hydrogen Sulphide gas is flammable and poisonous. Usually it is not a health risk at concentrations present in household water, except in exceptionally high concentrations. While such concentrations are rare, Hydrogen Sulphide's presence in drinking water when released in confined areas has been known to cause nausea, illness and, in extreme cases, death.
Water with Hydrogen Sulphide
alone does not cause disease. In rare cases, however, Hydrogen Sulphide odor may
be from sewage pollution which can contain disease-producing contaminants. Therefore,
testing for bacterial contamination and Sulfate Reducing Bacteria is highly
Hydrogen Sulphide may be temporarily controlled by conducting a shock chlorination / disinfection of the well or water source. Please visit the Shock Chlorination page to get more information on this protocol. If the problem with the well is because of Sulfate Reducing Bacteria, a high level of chlorination, mixing, and turbulence may be needed.
To remove low levels of Hydrogen Sulphide, install an activated carbon filter. The filter must be replaced periodically to maintain performance.
Hydrogen Sulphide concentrations up to about 5 to 7 ppm can be removed using an oxidizing filter. These filters are similar to the units used for iron treatment . This filter contains sand with a manganese dioxide coating that changes Hydrogen Sulphide gas to tiny particles of sulfur that are trapped inside the filter. The sand filter must be backwashed regularly and treated with potassium permanganate to maintain the coating.
Hydrogen Sulphide concentrations exceeding 7 to 10 ppm can be removed by injecting an oxidizing chemical such as household bleach or potassium permanganate followed up by filtration. The oxidizing chemical should enter the water upstream from the storage or mixing tank to provide at least 30- 45 minutes of contact time between the chemical and water. The length of the holding time is a function of the chemical dosage, tank configuration, and water temperature. Sulfur particles can then be removed using a sediment filter and the excess chlorine can be removed by activated carbon filtration. When potassium permanganate is used a manganese greensand filter is recommended.
Iron— is the fourth most abundant element, by weight, in the earth's crust. Taste thresholds of iron in water are 0.1 mg/l for ferrous iron and 0.2 mg/l ferric iron, giving water a bitter or an astringent taste. Water that is high in iron and manganese may have a metallic or medicinal taste. The five forms of iron commonly found in drinking water are:
Water contaminated with ferrous iron appears clear when first drawn at the cold water faucet because the iron is completely dissolved. When ferrous iron is exposed to air, it becomes ferric iron which is red in colour.
Water that is high in iron causes brown-yellow-red stains appear on porcelain fixtures or fixtures where water stands or drips. They also appear on laundry, particularly if chlorine bleach is used.
Manganese — is rarely found alone in a water source but is generally found with dissolved iron and acts in a manner similar to iron. Evidence of manganese staining is usually most prominent in the dishwasher. The detergents used to wash the dishes raise the pH of the water high enough (>8) to allow the manganese to precipitate easily. The manganese forms a film that is sometimes mistaken for oil on the water. If you touch the surface of this water the film will break into flakes with jagged edges.
Shock chlorination— There is a chance of bacterial contamination any time there is a new well or a water system fixture such as a pump is removed from a well and replaced. Bacterial problems are most common in shallow wells and areas with coarse textured soils and fractured bedrock or limestone. The major source of contamination is surface water, or septic tanks or sewage lines located too close to the well. Runoff or leaching from livestock operations can also contaminate wells.
Test the water for bacteria two weeks after shock chlorination to see if you have a recurring problem. Contact your local Health Department for information on water testing and well protection.
Shock chlorination can be done using ordinary laundry bleach (containing approx. 5.25 percent sodium hypochlorite right out of the jug) or calcium hypochlorite (containing 65%-75% available chlorine). The goal is to add enough chlorine to raise the chlorine concentration in the well to about 200 milligrams per liter to kill potentially harmful bacteria and viruses.
A thorough shock chlorination of the well and water system may destroy all iron bacteria colonies. However, if iron bacteria have penetrated the water-bearing formation they will be difficult to eliminate and will likely re-infest the system. In this situation you will need to repeat chlorination treatment periodically.
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