Design Guide for Community Water Systems - The Water, Sanitation ...

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Where phosphate treatment is used, provisions for disinfecting thewater must be provided.2. Feeding equipment shall conform to the requirements of Chapter 5of this document.3. Stock phosphate solution must be kept covered and disinfected bycarrying approximately 10 milligrams per liter free chlorineresidual.4. Polyphosphates shall not be applied ahead of iron and manganeseremoval treatment. The point of application shall be prior to anyaeration, oxidation, or disinfection if no iron or manganeseremoval treatment is provided.5. Phosphate chemicals must be acceptable to the department.g. Sequestration by sodium silicates.1. Sodium silicate sequestration of iron and manganese is appropriateonly to groundwater supplies prior to air contact. On-site pilottests are required to determine the suitability of sodium silicate forthe particular water and the minimum dose needed. Chlorinationmust precede the introduction of sodium silicate. Addition ofsodium silicate must be within 15 seconds after the addition ofchlorine.2. Sodium Silicate addition is applicable to waters containing up to 2mg/L of iron, manganese or combination thereof.3. Equipment must be provided so that chlorine residuals can bemaintained throughout the distribution system to prevent biologicalbreakdown of the sequestered iron.4. The amount of silicate added shall be limited to 20 mg/L as Si0 2 ,but the amount of added and naturally occurring silicate shall notexceed 60 mg/L as Si0 2 .5. Feeding equipment shall conform to the requirements of Chapter 5of this document.6. Sodium silicate shall not be applied ahead of iron or manganeseremoval treatment.7. Quality of sodium silicate must be acceptable to the department.4.8. Control of Organic Contamination.Controlling organic contamination is an area of design that requires pilot studiesand early consultation with the department. Where treatment is proposed, the bestavailable technology shall be provided to reduce organic contaminants to the lowestpractical levels.4.8.1 Engineering Report.Except for temporary, emergency treatment conditions, particular attentionshall be given to developing an engineering report that, in addition to thenormal determinations in section 1.1, includes the following:Aug. 29, 2003Page 80
a. Types of organic chemicals, sources, concentrations, frequency ofoccurrence if in surface water or estimated residence time within theaquifer and flow characteristics if in ground water, water pollutionabatement schedule, etc.;b. Possible treatment alternatives;c. Results of bench, pilot, or full scale testing, demonstrating theeffectiveness and cost of the treatment alternatives; andd. A determination of quality and/or operational parameters which mayserve as the best measurement of treatment performance, and acorresponding monitoring and process control program.4.8.2 Control Alternatives.In general, the design of control and treatment alternatives for organiccontamination requires pilot or full scale testing. Collection of data pertinentto design is often complicated and lengthy. A permanent engineeringsolution for organic contamination may take significant time to develop. Thefollowing alternatives should be considered:a. Alternative source development or purchase of water from nearbyunaffected water systems may be a more expedient solution;b. Modifications of existing treatment to enhance organic removal;c. Air stripping for volatile organics. In designing the air stripping tower,consideration should be given to:1. Materials for tower, packing, and piping that are acceptable foruse in contact with potable water;2. Providing a moisture barrier (de-mister);3. Metering the water flow to the tower;4. Metering the air flow to the tower;5. Providing influent and effluent sampling taps;6. Disinfecting the water passing through the tower;7. Designing the tower and air to water ratio to reduce the criticalcontaminants to the lowest practical level;8. The air discharge meeting the air quality standards of theMissouri Air Conservation Commission;9. Provision for easy inspection, maintenance, and cleaning of thepacking materials. Iron and manganese precipitation, carbonatedeposition, and biological fouling are potential problems;10. Chemical stability of the finished water; and11. Acceptable supply during periods of maintenance and operationinterruptions; andd. Adsorption by granular activated carbon. Consideration should begiven to:1. Determining the filter isotherm for the particular contaminant tobe removed, and the minimum contact time with the carbon bedthat is necessary for removing the contaminant;2. Using contact units rather than replacing portions of existingfilter media;Aug. 29, 2003Page 81
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Design GuideforCommunity Water Syst
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2.18. AUTOMATION. .................
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4.3.11. Waste Disposal. ...........
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CHAPTER 6 -- MINIMUM CONSTRUCTION R
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Maximum Hour Demand -- The amount o
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(This page is intentionally blank.)
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and deviations are subject to indiv
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(blank)Aug. 29, 2003Page viii
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a. A description of the nature and
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a. Hydrological data, stream flow,
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4. Be conducted under the same oper
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maintaining the new technology and
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1.2.1. Plans shall include:a. Suita
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name, number, effective date, publi
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e. The site will provide all-weathe
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chlorine residual by methods in "St
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etween them, a six-inch band of con
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a. Regulated recreational activitie
Page 48: e done to determine the degree and
Page 51: 1. Pumping rate;2. Pumping water le
Page 55 and 56: sieve analyses of the water bearing
Page 57 and 58: e circulated in the annular space s
Page 59 and 60: emoved. Therefore, every well shoul
Page 61 and 62: 3.2.6.4. Pitless well units.a. The
Page 63 and 64: SIZE (inches)6 id.8101214 od.161820
Page 65 and 66: Chapter 4 -- Tre atment4.0. General
Page 67 and 68: settling basins shall be not less t
Page 69 and 70: 3. Shall have valves located outsid
Page 71: d. Be automatic. Timers on automati
Page 76 and 77: 2. Uniformity coefficient not great
Page 78 and 79: j. During air scour, the backwash w
Page 80 and 81: . An easily readable meter or flow
Page 82 and 83: 4.3.4. Design Pressure Drop or Tran
Page 84 and 85: 4.3.9. Flow Meters.Totaling rate of
Page 86 and 87: utilized, shall be 1.0 milligrams p
Page 88 and 89: . Removal of precursors prior to ch
Page 90 and 91: 5. Consideration shall be given to
Page 92 and 93: . Pre-treatment requirements. Iron,
Page 94 and 95: t. Housing. Bagged salt and dry bul
Page 96 and 97: 4.7. Iron and Manganese ControlIron
Page 100 and 101: 3. Series and parallel flow piping
Page 102 and 103: approval of the department before u
Page 104 and 105: contact time must be provided to co
Page 106 and 107: a. Sanitary sewers with the approva
Page 108 and 109: 1. Obtain a letter of approval from
Page 110 and 111: 6. The provisions for the final dis
Page 112 and 113: a. Missouri River or Mississippi Ri
Page 114 and 115: 5.0.3. General equipment design.Gen
Page 116 and 117: minimize chemical dust created by t
Page 118 and 119: 1. At least 30 days of chemical sup
Page 120 and 121: e. Hand pumps shall be provided for
Page 122 and 123: 5.2. Chemicals.5.2.1 Shipping conta
Page 124 and 125: outside atmosphere, above grade and
Page 126 and 127: 5.4.2. Acids.a. Acids shall be kept
Page 128 and 129: 4. Anhydrous ammonia contact with c
Page 130 and 131: combustible material.2. Powdered ac
Page 132 and 133: fluoride feed line when a metering
Page 134 and 135: possibility for overfeed.h. Protect
Page 136 and 137: caution.d. Where taste and odor con
Page 138 and 139: e installed to monitor the flow of
Page 140 and 141: the generator dielectrics. Sufficie
Page 142 and 143: published by the National Fire Prot
Page 144 and 145: g. Water from pump gland drainage s
Page 146 and 147: 6.3. Pumps.6.3.1.Pumps shall be siz
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6.4.2.2. Suction lines.Suction line
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cessation of minimum essential serv
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parameters: average winter (Decembe
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a. Overflows shall be sized to perm
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additional shielding to prevent the
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largest pump out of service shall b
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7.1.4. CostsAs part of the final en
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7.4. Hydropneumatic Storage7.4.1. H
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provided on larger tanks as needed
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7.5.2. Fire Suppression Rating Sche
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in areas served by rural water dist
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connected directly to any sewer. Su
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8.6.5. Force mains.There shall be a
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8.11.2. Filling device.A filling de
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