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Summary of changes
Water System Design Manual
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Amy Swecker.
Manual
cover
and table of contents
(downloadable)
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TABLE OF
CONTENTS
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CHAPTER &
SECTION
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CHAPTER & SECTION TITLE
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PAGE
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PREFACE |
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GLOSSARY |
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1
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INTRODUCTION
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1-1
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1.0
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Purpose and Scope
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1-1
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1.1
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Applicability
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1-1
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1.2
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“Must” versus “Should” etc.
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1-2
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1.3
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Relationship with Planning Requirements
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1-2
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1.4
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Engineering Requirements
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1-3
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1.5
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General Engineering Project Submittal Requirements ...............
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1-4
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1.6
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Minimum System Design Requirements
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1-4
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1.7
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Sizing Criteria and Water Rights
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1-4
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1.8
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DOH Policies, Procedures and
Guidelines…...............................
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1-4
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1.9
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Ten States Standards
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1-5
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1.10
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State Environmental Policy Act (SEPA) Considerations ..……..
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1-5
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1.11
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Other Referenced Documents and Standards
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1-5
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2
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PROJECT REPORTS
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2-1
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2.0
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Relationship to Water System Plan (WSP)
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2-1
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2.1
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Submittal to DOH for Review and Approval
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2-1
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2.2
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Project Report Contents
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2-1
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3
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CONSTRUCTION DOCUMENTS
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3-1
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3.0
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Relationship to Water System Plan (WSP)
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3-1
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3.1
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Submittal to DOH for Review and Approval
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3-1
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3.2
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Design Drawings
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3-2
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3.3
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Project Specifications
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3-3
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3.4
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Change Orders
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3-4
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3.5
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Contracted Components for a Project …………………..
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3-4
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4
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PROCESS FOR REVIEW AND APPROVAL OF PROJECT REPORTS AND CONSTRUCTION
DOCUMENTS
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4-1
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4.0
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When Documents Required
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4-1
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4.1
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Coordination with Local Approving Authorities
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4-1
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4.2
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Project Report Requirements
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4-1
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4.3
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Project Report and Construction Document Screening and Review
Process
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4-2
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4.4
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Submittal Exceptions - Miscellaneous Components and Distribution
Mains
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4-3
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4.5
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Submittal Exceptions for Distribution-Related Projects
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4-4
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4.6
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Source Approval and Water Rights
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4-7
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4.7
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Resolution of Disputed DOH Review Decisions
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4-8
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4.8
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Review Fees and Invoice
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4-8
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4.9
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Project Approval Letter & Construction Completion ..................
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4-9
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4.10
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Construction Completion Report (CCR) Forms
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4-9
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5
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WATER DEMAND REQUIREMENTS
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5-1
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5.0
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Applicability
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5-1
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5.1
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Estimating Demands vs. Actual Use Data
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5-1
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5.2
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Residential Water Demand Design Criteria
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5-2
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5.3
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Documentation of Water Demand
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5-9
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5.4
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Estimating Nonresidential Water System Demand
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5-11
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5.5
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Water Demand Forecasting
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5-16
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5.6
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Other Regulatory Considerations
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5-17
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5.7
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General System Reliability ………………………………………….
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5-17
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6
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WATER SYSTEM PHYSICAL CAPACITY ANALYSIS (ERUs)
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6-1
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6.0
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Applicability
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6-1
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6.1
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Background
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6-2
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6.2
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Relationship Between System Capacity and Physical Capacity
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6-2
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6.3
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Fundamental Design Principle for Physical Capacity Analysis ..
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6-2
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6.4
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The Concept of Equivalent Residential Units (ERUs) ................
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6-2
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6.5
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Design Factors
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6-5
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6.6
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The Relationship Between Physical Capacity and Drinking Water
Operating Permits (Chapter 246-294 WAC)
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6-6
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6.7
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Methodology to Determine System Physical Capacity
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6-6
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7
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SOURCE OF SUPPLY
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7-1
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7.0
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Water Resource Analysis and Water Rights
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7-1
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7.1
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Source Water Quantity
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7-2
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7.2
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Source Water Quality and Protection
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7-3
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7.3
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Ground Water Sources (Wells)
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7-6
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7.4
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Spring Sources
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7-9
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7.5
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New Surface Water Supplies
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7-11
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7.6
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Interties
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7-11
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7.7
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General Reliability Considerations ………………………………..
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7-12
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7.8
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General Source Considerations
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7-12
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8
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TRANSMISSION AND DISTRIBUTION MAIN DESIGN
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8-1
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8.0
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Transmission and Distribution Main Definitions
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8-1
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8.1
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System Distribution Facility Sizing
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8-1
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8.2
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Hydraulic Analysis
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8-4
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8.3
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Materials
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8-12
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8.4
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General Design Consideration for Mains
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8-13
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8.5
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Appurtenant Design Considerations
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8-14
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8.6
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Layout of Mains
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8-16
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8.7
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Detail Drawings
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8-17
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8.8
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Standard Construction Specifications
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8-17
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8.9
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Cross-Connection Protection
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8-19
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8.10
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Chapter 8 References
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8-19
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9
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RESERVOIR DESIGN AND STORAGE VOLUME
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9-1
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9.0
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Storage Volume Components
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9-1
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9.1
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Reservoir Sizing Considerations
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9-7
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9.2
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Establishing Overflow Elevation
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9-9
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9.3
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System Pressure Considerations
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9-10
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9.4
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Site Feasibility Considerations
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9-11
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9.5
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Special Design Considerations Based on Type of Reservoir ....
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9-11
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9.6
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Reservoir Appurtenant Design
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9-13
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9.7
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Operational Constraints and Considerations
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9-15
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9.8
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Reservoir Structural Design
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9-16
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10
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BOOSTER PUMP STATION (BPS) DESIGN
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10-1
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10.0
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Select Applicable Booster Pump Station Type
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10-1
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10.1
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Determination of Pumping System Discharge Capacity Requirements ……………………………………………………….
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10-2
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10.2
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Hydraulic Design Requirements for Supplying System
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10-4
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10.3
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Mechanical Design Considerations
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10-5
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10.4
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BPS Appurtenant Design
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10-5
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10.5
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Back-up Power Requirements for Closed System BPS
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10-7
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10.6
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BPS Structural Design
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10-8
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10.7
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Multiple Pump Design Considerations
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10-8
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11
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HYDROPNEUMATIC (PRESSURE) TANKS
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11-1
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11.0
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General
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11-1
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11.1
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Pressure Tank Sizing Procedure
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11-1
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11.2
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Requirements of the Department of Labor & Industries
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11-6
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11.3
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Locating Pressure Tanks
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11-7
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11.4
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Piping
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11-7
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11.5
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Pressure Tank Appurtenances
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11-7
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11.6
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Hydropneumatic Tank Sizing Associated with “Cycle
Stop Valves”
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11-7
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12
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WATER QUALITY AND TREATMENT
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12-1
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12.0
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Applicability
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12-1
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12.1
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Submittal Requirements
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12-1
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12.2
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Treatment Alternatives
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12-1
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12.3
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Analysis of Alternatives
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12-14
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12.4
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Evaluation Studies (Reference WAC 246-290-250)
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12-17
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12.5
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Project Report and Final Design Considerations
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12-22
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12.6
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Construction Documents (Reference WAC 246-290-120)
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12-26
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12.7
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Start-up, Testing, and Operation
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12-28
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12.8
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Related Policies and Guidelines
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12-28
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12.9
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Cross-Connection Control Considerations in Water
Treatment Facilities
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12-28
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12.10
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Chapter 12 References
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12-32
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13
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MISCELLANEOUS DESIGN CONSIDERATIONS
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13-1
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13.1
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Safety
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13-1
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13.2
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Protection from Trespassers
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13-4
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13.3
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Heat Exchangers
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13-4
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13.4
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Cross-Connection Control Protection
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13-4
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13.5
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Seismic Design
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13-8
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14
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CONSTRUCTION INSPECTION AND FINAL APPROVAL
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14-1
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14.1
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Construction Report Form
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14-1
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14.2
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Water Facilities Inventory (WFI) Form
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14-1
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14.3
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Pressure and Leakage Test
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14-1
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14.4
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Disinfection
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14-2
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14.5
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Disposal of Chlorinated Water and Dechlorination Process ......
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14-2
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14.6
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Microbiological Test
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14-3
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14.7
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Pipelines
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14-3
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14.8
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Storage Reservoirs
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14-3
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14.9
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Pumps and Controls
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14-4
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14.10
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Treatment Systems
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14-4
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14.11
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Change Orders
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14-4
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14.12
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Documentation When No DOH Approval Required
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14-5
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14.13
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Record Drawings
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14-5
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APPENDICES
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A
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List of DOH Drinking Water Policies and Procedures (contact our
office) |
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B
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Copies of Selected Guidelines or Policies Referenced in the Water
System Design Manual |
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C
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List of Agencies and Publications Referenced in the Water System
Design Manual |
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D
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Background and Development of Residential Water Demand vs.
Precipitation |
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E
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Recommended Pumping Test Procedures |
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F
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Obtaining Approval for Wells as Public Drinking Water Sources |
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G
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Additional Water Treatment Guidance Documents |
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H
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Guidance for Leachable Contaminant Testing Procedures |
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I
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Ultraviolet Light Disinfection for Drinking Water Applications
Appendix I Attachment |
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