IRON, MANGANESE AND HYDROGEN SULFIDE IN PRIVATE WATER SUPPLIES

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1 IRON, MANGANESE AND HYDROGEN SULFIDE IN PRIVATE WATER SUPPLIES

2 Percent Failing Standard Water Quality Problems in PA Blue bars = aesthetic problems Red bars = health problems *no statewide data for hydrogen sulfide

3 Percent Above Standard 1 50 Iron, Manganese and Sulfate (Penn State AASL Lab) Iron (n=1973) Manganese (n=1960) Sulfate (n=271)

4 Iron Common mineral in soil and rock Occurs naturally or from any disturbance activity (mining, construction, drilling, etc.) Form and concentration is important Oxidized = visible, orange stain Reduced = colorless Secondary (aesthetic) drinking water standard of 0.30 mg/l

5 OXIDIZED (FERRIC) IRON

6 DISSOLVED (FERROUS) IRON

7 Percent Above Standard 50 Regional Occurrence of Iron (1985 survey) Iron > 0.3 mg/l 10 0 NW SW NC SC NE SE Region of PA

8 Occurrence of Iron in Drinking Water % of samples exceeding 0.30 mg/l Iron For counties with at least 20 water samples

9 Percent of Samples Drinking Water Standard 50 Iron Distribution in Water Samples ,230 raw water samples (2007 to present) Highest = mg/l Treatment implications Iron Concentration (mg/l)

10 Manganese Also common mineral in soil and rock Occurs naturally or from any disturbance activity (mining, construction, drilling, etc.) Some dispute about health effects from manganese World Health Organization (WHO) set health-based standard of 0.40 mg/l in 2004 (standard removed in 2011) Neurologic effects Picture - Secondary drinking water standard = 0.05 mg/l

11 MANGANESE OCCURRENCE U.S. GEOLOGICAL SURVEY

12 Occurrence of Manganese in Drinking Water % of samples exceeding 0.05 mg/l Manganese For counties with at least 20 water samples

13 Percent of Samples Drinking Water Standard WHO Past Health-Based Standard Manganese Distribution in Water Samples 60 1,154 raw water samples (2007 to present) Highest = mg/l Iron Concentration (mg/l)

14 Iron (mg/l) Iron/Manganese Correlation Manganese (mg/l)

15 Iron (mg/l) Metals Correlations to ph Iron Manganese ph

16 Hydrogen Sulfide Dissolved gas in water, harmless but noxious odor No drinking water standard Difficult to test in water nose is best test Common natural problem Occurrence = 11.4% based on survey of 701 wells in 2007 Certain shale formation are notorious for hydrogen sulfide Often occurs with iron and/or manganese Groundwater origin = hot and cold water Hot water heater reactions = hot water only

17 Percent Above Standard 50 Sulfate Occurrence in Private Water Supplies Sulfate > 250 mg/l 10 0 NW SW NC SC NE SE Region of PA

18 Other Important Issues with Iron, Manganese and Hydrogen Sulfide Dairy Farms Dairy cows need several pounds of water for each pound of milk produced A single cow may consume over 200 lbs of water daily via drinking water and ration Aesthetic water quality problems can cause reduced milk production due to low water intake

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20 Project Summary 174 dairy farms tested in 2012 Focused on basic water quality parameters: ph, total dissolved solids (TDS), nitrate-n, hardness, calcium, magnesium, sodium, iron manganese, chloride, sulfate and copper

21 Relation of Water Quality to Milk Production? Overall, 26% of the water supplies tested had at least one test result that could cause reduced milk production (iron, manganese, etc.) Average milk production for these farms was 56 pounds per cow per day Average milk production for farms with good water quality was 62 pounds per cow per day Farms with >75 lbs of milk per cow = 0% water quality problems Farms with <50 lbs of milk per cow = 32% water quality problems

22 % of Farms Tested Relation of Water Quality and Milk Production milk production % poor water quality < Average Pounds Per Cow Per Day

23 Treatment Options Filtration oxidized iron and manganese Shock disinfection hydrogen sulfide Carbon filtration hydrogen sulfide Softening iron, some manganese Chlorination - all Oxidizing filters - all Aeration hydrogen sulfide

24 FILTRATION Removal of oxidized iron and manganese Filter sizes vary 5 micron, 20 micron, etc. Typical replacement frequency = 2-3 months Whole house units may be necessary backwash

25 Shock Chlorination Often effective at reducing or eliminating hydrogen sulfide for some period of time X

26 Water Softening Ion Exchange: Sodium for Calcium & Magnesium Raw Water Calcium & Magnesium RESIN (Sodium Or Potassium) Only effective for low to moderate concentrations of dissolved iron (< 3.0 mg/l)and very low manganese (<0.10) Iron and manganese can foul resin over time Often only used where hardness is moderate to high Treated Water (Sodium or Potassium)

27 Continuous Chlorination Effective on high concentrations of dissolved iron, manganese and hydrogen sulfide Filtration needed to remove oxidized material Can also remove sediment iron Best for cases where iron bacteria or other bacteria are present or where high concentrations exist

28 Oxidizing Filters Oxidize and filter low to high concentrations of iron, manganese and hydrogen sulfide Options Greensand Antrasand (anthracite sand) Zeolite ph of water must be at least 7.0 Backwashing necessary to remove oxidize metals

29 RO Unit Pre-filter Sediment Carbon

30 Other Options Just for Hydrogen Sulfide Hot water heater reactions = hot water only remove or replace rod in heater Carbon filtration Good for low concentrations Must change carbon routinely Aeration Oxidizing filter manganese greensand

31 Typical Iron Problem Test Result Maximum Contaminant Level (MCL) Coliform bacteria 0 /100 ml <1 /100 ml Nitrate-N 0.7 mg/l 10 mg/l Turbidity 0 NTU* <1 NTU ph to 8.5 Hardness 17 mg/l 1 gpg** No MCL (7-10 gpg is very hard) Iron 3.5 mg/l 0.3 mg/l SMCL***

32 Scenario 1 - Chlorination Feed Pump Solution Tank Pressure Tank Retention Tank Carbon Filter

33 Scenario 2 Oxidizing Filter Pressure Tank Iron Filter Solution Tank

34 Scenario 3 Water Softener Pressure Tank Water Softener Solution Tank

35 Tips for Buying Treatment Equipment Seek reputable companies that have been around Ask for customer references Research company history Beware of hard sale techniques (scare tactics) Ask about maintenance requirements Get a detailed warranty Look for NSF and WQA certifications EPA certification means nothing Get everything in writing! If it sounds too good - it is!

36 Educational Resources