Spec_Vol_5_2_W912PL-12-R-0018.pdf

FY12 WATER TREATMENT AND DISTRIBUTION SYSTEM SPECIFICATION NO.: 1858

FT. IRWIN, CA

APPENDIX V CONTINUED

FOR INFORMATION ONLY

ENGINEER’S REPORT FOR CORROSION ENGINEERING

EVALUATION OF THE 1.0 MG WELDED STEEL WATER

STORAGE TANK, HARPER & ASSOC. ENGINEERING,

INC., DECEMBER 2007

JPL-3 REPORT

APPENDIX W

FORT IRWIN CIP PROJECT WI

INVESTIGATION FOR THE COMBINATION

OF THE DO AND RO WATER SYSTEMS

CONTRACT DACA97-02-D-0037

D r a f t S u b m i t t a l

Fort Irwin CIP Project W1 Investigation for the Combination of the DO and RO Water Systems

Prepared for

The United States Army Fort Irwin, California

August 2007

P.O. Box 10450 Fort Irwin, CA 92310-0450

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Contents

Section ......................................................................................................................................Page

Executive Summary...................................................................................................................ES-1 Purpose..................................................................................................................................... ES-1 Summary .................................................................................................................................. ES-1

Existing Water Systems............................................................................................. ES-1 Regulations ................................................................................................................ ES-2 Future Conditions ...................................................................................................... ES-2 Recommended Single Drinking Water System Configuration ........................... ES-3 Transition Plan ........................................................................................................... ES-3

1.0 Introduction .............................................................................................................................1-1

1.1 Purpose...........................................................................................................................1-1

1.2 Scope of Work................................................................................................................1-1

1.3 Report Organization .....................................................................................................1-2

2.0 Existing Water System ..........................................................................................................2-1

2.1 Introduction ...................................................................................................................2-1

2.2 Domestic Water (DO) System .....................................................................................2-1

2.2.1 Description........................................................................................................2-1

2.2.2 Inventory...........................................................................................................2-2

2.2.3 Capacity Analysis ...............................................................................................2-2

2.3 Reverse Osmosis (RO) Water System ........................................................................2-7

2.3.1 Description........................................................................................................2-7

2.3.2 Inventory...........................................................................................................2-7

2.3.3 Capacity Analysis ............................................................................................2-7

2.4 Water Quality ................................................................................................................2-8

2.4.1 Federal and California Arsenic Rules ...........................................................2-8

2.4.2 Fort Irwin Drinking Water Quality Goals ....................................................2-8

2.4.3 Water Quality Sampling of Distribution System.......................................2-13

2.5 Regulatory Requirements and Applicable Standards for Water System Improvements .............................................................................................................2-14

2.5.1 State of California Domestic Water Supply Permit...................................2-14

2.5.2 U.S. Army Regulations..................................................................................2-15

2.5.3 Preparing a Distribution System for Compliant Potable Use..................2-15

2.5.4 Cleaning, Flushing, and Disinfecting Water Systems for Drinking Water

Use .................................................................................................................2-15

3.0 Proposed Capital Projects ....................................................................................................3-1

3.1 Capital Improvement Projects (Years 2006 through 2008)......................................3-1

3.2 Required Projects for Single Water System Combination.......................................3-1

3.2.1 New Water Treatment Plant (CIP Project W4) ............................................3-1

3.2.2 New Treated Water Storage Tank (CIP Project W10) .................................3-1

3.2.3 Bicycle Lake/Irwin Basin Transmission Pipeline (CIP Project W11) .......3-2

FORT IRWIN CIP PROJECT W1 INVESTIGATION FOR THE COMBINATION OF THE DO AND RO WATER SYSTEMS iv FIR_DRAFT REPORT - WATER DISTR. SYS. COMBI. STUDY_2AUG07_BMGG_REV14.DOC

4.0 Single Water System Configuration Hydraulic Evaluation ..........................................4-1

4.1 Key Design Criteria ......................................................................................................4-1

4.1.1 Hydraulic Model..............................................................................................4-1

4.2 Year 2007 Capacity Analysis ..............................................................................................4-3

4.2.1. Existing System ADD......................................................................................4-4

4.2.2. Existing System MDD .....................................................................................4-4

4.2.3. Existing System PHD ......................................................................................4-4

4.2.4. Existing System Fire Flow...............................................................................4-7

5.0 Recommended Single Drinking Water System Configuration ....................................5-1

5.1 Conversion to Single Drinking Water Distribution System....................................5-1

5.2 Untreated Water Supply to WTP................................................................................5-1

5.3 Treated Water Supply to the Cantonment ................................................................5-2

6.0 Transition Plan.......................................................................................................................6-1

6.1 DO and RO Water System Operations During Transition......................................6-1

6.2 Preparation of Existing DO Water Distribution System for Single Water System

Use...................................................................................................................................6-1

6.2.1 Flushing of Existing Distribution System.....................................................6-1

6.2.2 Disinfection of Existing Distribution System...............................................6-1

6.2.3 Chemical Deposits in Existing Distribution System ...................................6-1

6.3 Water Quality Evaluation Before and During Transition .......................................6-2

Tables 2-1 Domestic Water System Inventory..........................................................................................2-2 2-2 Reverse Osmosis Water System Inventory.............................................................................2-7 2-3 Fort Irwin Proposed Water Quality Goals ...........................................................................2-13 2-4 Fort Irwin Water Distribution System Water Quality Monitoring ...................................2-14 4-1 2006 System Demand by Pressure Zone.................................................................................4-2 4-2 Fire Flow Zone Requirements ..................................................................................................4-2 4-3 Minimum and Maximum Operating Pressures.....................................................................4-3 6-1 Water Quality Monitoring Within the Fort Irwin Water Distribution System .................6-2

Figures ES-1 Single Drinking Water System Flow Schematic.................................................................... ES-4 2-1 Current Year 2007 Domestic Water and Reverse Osmosis Water Distribution Systems ...2-3 2-2 Existing DO Water Distribution System ...................................................................................2-5 2-3 Existing RO Water Distribution System....................................................................................2-9 2-4 RO System Pressure Deficiencies .............................................................................................2-11 4-1 Model Nodes Classified by Fire Zone .......................................................................................4-5 4-2 Existing Water Distribution System Pressure and Velocity Analysis (2007 PHD

Condition)......................................................................................................................................4-8 4-3 Existing Water Distribution System – 2007 Fire Flow Deficiencies.....................................4-10 5-1 Single Drinking Water System Configuration..........................................................................5-4

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Executive Summary

Purpose This report is submitted to fulfill the requirements of the scope of work for CIP Project W1, Water Distribution Pipe System Combination Investigation, Task Order 3 (TO3) of Contract No. DACA97-02-D-0037.

This study was completed to determine the work necessary to combine the DO and RO water distribution systems into a single drinking water distribution system. The study work included revision of existing hydraulic models to reflect planned year 2007-2008 construction and operational changes; development of a recommended final operating configuration for the combined single drinking water system and development of recommended capital improvement plan (CIP) projects for converting DO and RO water distribution systems into a single drinking water system.

Summary Existing Water Systems The Fort Irwin water supply system serves a population of 10,000 residents, 3,500 non-resident civilian day workers and between 4,000 and 6,000 soldiers during rotational troop training periods. Two grades of water (drinking and domestic) are delivered to consumers through two independent storage and distribution systems. All water is produced from deep wells from three groundwater basins: Irwin Basin, Bicycle Lake Basin and Langford Lake Basin.

The existing drinking water supply system has a capacity of 150,000 gallons per day (gpd) and employs a reverse osmosis (RO) treatment system to control fluoride and keep other source water contaminants in compliance with Federal and State of California drinking water standards. The RO water is delivered to residences and most buildings on the Post through a separate RO water distribution system. Separate RO water fixtures are provided in the buildings and residences.

The RO distribution system hydraulic model, originally developed by CH2M HILL in 2003, was updated to include the new construction that has occurred since then. The model results confirm operating experience that the major problems with the RO system are long distribution lines that are too small to provide adequate flow to customers. Low pressures exist in many areas, especially in the Commander’s Loop area.

The domestic (DO) water system supplies consumers with disinfected groundwater that is used for all other domestic needs, such as bathing, irrigation, toilet flushing, laundry, etc. Ground-water distributed through the domestic water system contains fluoride and, from time to time, arsenic that exceed the current State of California maximum contaminant level (MCL) for drinking water.

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The 2003 DO water distribution hydraulic model was updated to reflect year 2007 operating conditions and new construction that has occurred since the initial model development by CH2M HILL. A hydraulic evaluation was performed to determine current year 2007 operating conditions and to identify any hydraulic capacity issues. The DO system does not have any areas of low pressure during Average Daily Demand (ADD) conditions. There are, however, large areas where pressure is greater than 80 psi under the same demand conditions. During Peak Hourly Demand (PHD) conditions, a low-pressure area exists along Silver Mine Drive and Gold Nugget Way. During PHD conditions, the high-pressure areas, though smaller in size, still exist. Low fire flow conditions exist along the eastern quarter of the system in two areas. This is caused by long distribution lengths and small main diameters.

Regulations Water from the existing DO water distribution system is considered “potable” as defined in the January 15, 2004, State of California Domestic Water Supply Permit to the United States Department of the Army for the Fort Irwin Water System (permit number 03-13-04(P)-001) issued by the California Department of Health Services (DHS). In this permit, DHS determined that the use of a two-pipe system to deliver water to a community system for all domestic uses (including drinking) does not comply with the Water Works Standards (California Code of Regulations Title 22, Division 4, Chapter 16) and all applicable regulations. According to the permit, both existing distribution systems at Fort Irwin provide potable water, the difference being that the RO system is in compliance and the DO system is not due to elevated levels of constituents such as arsenic and fluoride.

As a consequence of the DHS determination, all water delivered to consumers must meet all State and Federal drinking water requirements. To comply with the requirements, a new water treatment plant (WTP) must be constructed capable of producing all of the water used at Fort Irwin (i.e., a peak of approximately 6 million gallons per day). To distribute water of a single quality to all Fort Irwin facilities, the existing DO and RO water distribution systems must be combined, as necessary, into a single drinking water distribution system serving all uses at Fort Irwin. This transition of the distribution system from a dual water system to a single drinking water system requires preparation of the distribution system for drinking water use from an existing potable use. A transition plan for converting the dual distribution system to a single drinking water distribution system was developed.

Future Conditions The DO and RO water system hydraulic models were updated to include CH2M HILL water system capital improvement projects and Army development projects planned to be completed over the 3 years from January 2007, through the end of 2009.

CH2M HILL has proposed several related water system capital improvement projects required to be completed in addition to the conversion of the DO and RO water system into a single drinking water system (DW) by March 31, 2009. Detailed project descriptions are included in the Final Submittal, 2007 Capital Improvement Plan for the Water and Wastewater Utility Systems, Fort Irwin, California (CH2M HILL, February 23, 2007).

The Army is currently planning to have new facilities constructed and occupied by the anticipated conversion date (Year 2009) of the dual water system into a single drinking water

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system. The Army has indicated the new Army facilities will include: 11th Armored Cavalry Regiment (ACR); Combat Support Brigade (CSB); Sleepy Hollow Residential Communities Initiative (RCI) Housing and Towne Center.

Recommended Single Drinking Water System Configuration The recommended single drinking water system will reuse the existing DO water distribution system, with modifications as described below, and discontinue using the existing RO distribution system. Figure ES-1 presents a general flow diagram of the single drinking water distribution system. Generally, the flow path of the water from the well fields to the distribution system will be revised as follows.

• Bicycle Lake booster pumps will deliver disinfected well water to the new Water Treatment Plant through construction of CIP project W11, Bicycle Lake Water Main to New WTP.

• Irwin well I-7 will deliver disinfected well water to the new WTP through a new, 8-inch water transmission main to the new Bicycle Lake Water Main constructed as part of CIP project W11 .

• The Langford Lake booster pumps will deliver disinfected well water to the new WTP through its existing transmission main connected to the CIP project W11 main near the new

WTP.

• The new 6-mgd WTP (CIP project W4) will treat the well water and then pump the treated drinking water to four storage tanks: three existing 1-MG JPL tanks and one new 1-MG tank constructed as part of CIP project W10.

• The storage tanks will deliver drinking water to the Cantonment the existing DO distribution system and a new water transmission main to the northeast intersection of Barstow Road and North Loop Road constructed as part of CIP project W11.

• Water consumers to the northeast of the intersection of Barstow Road and North Loop Road will be served with drinking water from a new 8-inch extension of the Cantonment drinking water distribution system as a part of CIP project W11

Transition Plan A transition plan has been developed for the conversion of the dual water system to a single drinking water distribution system. The following key plan elements have been developed to maintain the quality of the water supply at Fort Irwin during the transition:

• Clean and inspect (and repair if necessary) the existing water storage tanks. This project is already programmed in CH2M HILL's 2006 Annual Capital Improvement Plan (CIP project W15).

• Coordinate the single drinking water system transition with the new WTP process design to assure compatibility between treated water chemistry and the presence/absence and leaching potential of constituents in the pipe interiors of the existing distribution system.

• Flush the entire existing DO distribution system in preparation for operation as the single drinking water distribution system at Fort Irwin. The flushing will occur in phases across

ES-4 FIR_DRAFT REPORT - WATER DISTR. SYS. COMBI. STUDY_2AUG07_BMGG_REV14.DOC

Fort Irwin. A detailed flushing plan will be developed and coordinated with all affected Army operations, tenants and residences on post.

• Sample and analyze water quality within the distribution system to insure that public health is not compromised during and after transition to a single water system.

• Abandon the RO treatment plant and RO water distribution system after successful transition. Demolish the RO treatment plant and restore the site. Dewater the existing RO distribution system and abandon the RO system in-place.

Langford Lake Wells

Irwin Well I-7

Bicycle Lake Wells

W11 New Bicycle Lake Main

W11

1 MG

1 MG

1 MG

W4 New Water Treatment Plant

JPL2 JPL3

1 MG

W11 New

Transmission Main

Pump Station

Existing Cantonment Distribution

JPL Goldstone

Color Key:

Existing New

1 MG

JPL1

1 MG

JPL2

1 MG

JPL3

W10 New Tank

FIGURE ES-1

Single Drinking Water System Flow Schematic

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SECTION 1.0

Introduction

1.1 Purpose

The June 2005 Final System Upgrade, Expansion and Renewal (SUER) Plan described the Water Distribution Pipe System Combination Investigation objective and purpose as follows:

“…The independent domestic and RO water distribution systems are to be combined after the new water treatment facility is brought on line. Planning-level evaluations will be completed to determine the phasing of the conversion of the domestic water to a treated water distribution system. Analyses will be completed to determine necessary cross-connection locations, pumping and pressure reducing valve requirements. A computer hydraulic model will be developed for the combined system to analyze alternatives. The model will have value in making decisions about future connections, PRV locations, pumping requirements, etc., as the base population changes and new facilities are brought on line or taken out of service…“

“…When the new WTP is brought on line, it is planned to convert the domestic water distribution system to convey treated (i.e., potable) water in combination with the existing RO distribution system. This task will complete the planning studies necessary to sequence and combine the two systems. The conversion work must be completed in phases as the homes and base facilities are converted to a single-pipe water supply. The assessment will be completed to determine cross-connection locations, pumping requirements, and pressure reducing valve requirements and locations.“

1.2 Scope of Work

CH2M HILL performed the following work tasks for this investigation:

• Update the Project Characterization Report (Year 2003) domestic (DO) water and reverse osmosis (RO) water distribution system hydraulic models to reflect current year 2007 operating conditions

• Identify deficiencies in the current year 2007 DO water and RO water distribution systems

• Determine planned construction and operational changes that will occur prior to 2009 and will impact the conversion to a single-pipe distribution system

• Revise the current year 2007 DO water and RO water distribution system hydraulic models to reflect planned year 2009 construction and operational changes

• Identify deficiencies in the future year 2009 DO water and RO water distribution systems resulting from implementing planned construction projects from 2007 through 2009

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• Develop alternative, combined, single drinking water system operating scenarios and evaluate consolidating the eight existing pressure zones of the DO water system and the three pressure zones of the RO system into the fewest number of pressure zones

• Recommend a final configuration for projected year 2009 combined, single drinking water system operations, including capital project descriptions

• Develop phasing plans as necessary for converting the DO and RO water systems into a single-pipe water distribution system

• Recommend capital improvements for converting DO water and RO water distribution systems into a single drinking water system, including requirements for transition period activities

1.3 Report Organization

The report is organized into the following sections:

• Executive Summary

• Section 1, Introduction

• Section 2, Existing Water System Description

• Section 3, Proposed Capital Projects

• Section 4, Single Water System Configuration Hydraulic Evaluation

• Section 5, Recommended Single Drinking Water System Configuration

• Section 6, Transition Plan

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SECTION 2.0

Existing Water System

2.1 Introduction

Fort Irwin has a current equivalent population of approximately 19,300 people composed of approximately 10,000 resident soldiers and dependents, approximately 3,500 civilian and contractor day-workers, and a monthly average of approximately 5,800 rotational trainee forces.

However, the population can be as high as 22,000 during routine troop training rotations, which typically last 4 to 6 weeks. Water demand at Fort Irwin fluctuates due to troop rotations and seasonal irrigation demands.

Irwin Basin, Bicycle Lake Basin, and Langford Lake Basin groundwater aquifers supply all of the water used at Fort Irwin. Two grades of water are distributed through two independent storage and distribution systems. Figure 2-1 shows the general layout of the two water distribution systems, including wells, storage tanks, pump stations, treatment plant, and PRV locations.

Drinking water is produced by removing fluoride, arsenic, and other constituents from the domestic groundwater source by reverse osmosis (RO). The existing RO treatment plant is capable of producing approximately 150,000 gallons per day (gpd). The RO water is delivered into most buildings on Post through a separate RO water distribution system. In residences, the RO water is dispensed through a single faucet at the kitchen sink, and in some newer homes and buildings, through a faucet at the bathroom sink.

The domestic (DO) water distribution system provides water for all other uses, such as bathing, irrigation, toilet flushing, laundry, fire-fighting, etc. After being disinfected with sodium hypochlorite, groundwater is distributed through the DO water system to most buildings and facilities on post. DO water contains fluoride that exceeds the current maximum contaminant level (MCL) and arsenic that is expected to exceed the State of California MCL.

The topography of the post is relatively uniform, sloping from the northwest to the southeast.

The storage tanks are located at the highest point in the system, while the facilities southeast of South Loop Road are at the lowest point. This change in elevation results in increased water pressure as the water is conveyed from the high point to the low point.

2.2 Domestic Water (DO) System

2.2.1 Description

Figure 2-2 shows the general layout of the domestic water system. The DO water system is fed from wells located at Bicycle Lake, Langford Lake, and the Irwin Basin well field. Booster pumping stations are located at both Bicycle Lake and Langford Lake. The Bicycle Lake booster pumping station consists of a 500,000-gallon storage tank and three booster pumps. The Langford Lake booster pumping station consists of a 110,000-gallon storage tank and three

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booster pumps. DO water is disinfected with sodium hypochlorite at the booster pump stations and at the well heads in the Irwin Basin.

The DO water is pumped to four storage tanks, and the water is gravity-fed through the pipe system based on demand. Three 1-million-gallon (MG) above-ground tanks (JPL 1, JPL 2, and JPL 3) are located on the hill to the west of the Cantonment. The upper residential portions of the Cantonment are supplied by tanks JPL 2 and JPL 3. Tank JPL 1 supplies water to the stables and the NASA Goldstone facility. A 1-MG underground storage tank, located in the northern residential area, serves lower pressure zones in the Cantonment.. There are eight pressure zones associated with the DO system. Pressure zones 2778 and 2632 are supplied directly from the JPL storage tanks. Pressure zones 2612, 2615, 2630, 2655, 2657, and 2748 are supplied from higher pressure zones and are regulated by pressue reducing valves (PRVs).

2.2.2 Inventory

The DO distribution system contains approximately 61 miles of piping, ranging in size from 2 to 16 inches in diameter, with the oldest pipe installed in 1952. A summary of the DO pipe inventory is presented in Table 2-1. This inventory was based upon the existing hydraulic model that was developed from the US Army GIS database by CH2M HILL in 2003.

TABLE 2-1

Domestic Water System Inventory

Pipe Length (feet) by Material Type Water Main Diameter

(inch) Length (feet)

Percentage of Total

(%) Transite Cement-Lined

Cast Iron Cast Iron

Galvanized Steel PVC Steel

2 6,398 2.0 338 85 332 2,891 2,752 -

4 7,068 2.2 3,081 - 2,740 1,278 -

6 36,763 11.4 25,285 - 1,350 - 8,649 1,479

8 184,399 57.3 50,035 5,443 2,143 29 126,749 -

10 12,274 3.8 4,659 1,254 - - 6,361 -

12 19,988 6.2 1744 2,129 908 - 15,207 -

14 705 0.2 - 705 - - - -

16 53,949 16.8 2,652 27,864 551 22,882 -

Totals 321,544 100.0 87,794 37,480 5,284 5,628 183,879 1,479 Note: Length totals do not include any portion of the RO system.

Based on the September 2006 Pipe Corrosion and Leak Detection project report, the following is known about the condition of the DO distribution system piping:

• In general, the DO water mains are considered suitable for continued service.

• No current leaks were found in buried metallic piping, and only three valve leaks were identified.

• Based on the soil resistivity and soil chemistry testing, the Fort Irwin soil conditions would be considered only mildly to moderately corrosive.

2.2.3 Capacity Analysis

See Section 4.0 for a discussion of the DO system capacity.

5th Street

3rd Street

8th Street

G A ve nue

Rhin eland D riv e

Por k

Cho p

Hill Stre et

Land Fill Road

Nor m an dy

D riv e

4th Street

9th Street

7th Street

Langford Lake R oad

Salerno Drive

B A ve nu e

5th Street

5th Street

B A ve nu e

8th Street

Alvord Drive

South Loop R oad

North Loop R oad

Goldstone Road

In ne r L oo p Roa d

Bar st ow R oa d

N orth Loop R oad

Bar st ow R oa d

R hin e la n d

D rive S ou th

L oo p R oa d

Inner Loop R oad

RO Plant

From Langford Lake

Fro m

Bicy cle

Lak e

0 1,000 2,000500 Feet

Figure 2-1 Currrent Year 2007 Domestic Water and Reverse Osmosis Water Distribution Systems

Existing PRV

Well

Tank

RO Plant

DO System

RO System

Combination DO and RO Water Systems

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FromBicycle Lake

5th Street

3rd Street

8th Street

G Ave nue

Rhin ela nd D riv e

Por k

Cho p

Hill Stre et

Land Fill Road

Nor m an dy

D riv e

4th Street

9th Street

7th Street

Langford Lake R oad

Salerno Drive

5th Street

B A ve nu e

5th Street

5th Street B A ve nu e

8th Street

Alvord Drive

South Lo op R oad

North Loop R oad

Goldstone Road

In ne r L oo p Roa d

Bar st ow R oa d

N orth Loop R oad

Bar st ow R oa d

R hin e la n d

D rive

So ut h Lo op R oa d

Inner Loop R oad

FromLangford Lake

0 1,000 2,000500 Feet

Figure 2-2 Existing DO Water Distribution System

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Pressure Zone

Well

Tank

Existing PRV

Existing Pipe

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2.3 Reverse Osmosis (RO) Water System

2.3.1 Description

Figure 2-3 shows the general layout of the RO water distribution system. A water treatment plant located near the center of the Cantonment produces the RO water. DO water is the feedwater for the RO plant. The RO water is pumped from the RO plant to three storage tanks and, based on demand, is gravity-fed through the pipe system. A 20,000-gallon RO storage tank is located on the hill below tanks JPL 2 and JPL 3. Additional 150,000-gallon and 250,000-gallon RO storage tanks are located south of the underground DO storage tanks. Booster pumps at the RO plant supply water to the tanks, Three pressure zones are associated with the RO system.

Pressure Zone 2707 is supplied from the 20,000-gallon tank. Pressure Zone 2623 is supplied from the 150,000-gallon and 250,000-gallon tanks, and Pressure Zone 2575 is supplied from the RO plant.

2.3.2 Inventory

The majority of the 28-mile-long RO distribution system piping, which range from ¾ to 8 inches in diameter, was installed between 1956 and 1996. A summary of the RO water pipe inventory is presented in Table 2-2. This inventory was based upon the existing hydraulic model that was developed from the US Army GIS database.

TABLE 2-2

Reverse Osmosis Water System Inventory

Pipe Length (feet) by Material Type Water Main Diameter

(inch) Length (feet)

Percentage of Total

(%) Transite

Cement- Lined

Cast Iron Cast Iron

Galvanized Steel PVC Steel

3/4 345 0.3 - - - 345 -

1 9,904 6.5 - - - 9,646 259 -

1 1/4 3,356 2.2 - - - 1,452 1,905 -

1 1/2 4,854 3.2 - - - 3,392 1,463 -

2 59,197 39.0 1,047 - 17,396 40,754 -

2 1/2 2,605 1.7 - - - - 2,605 -

3 4,157 2.7 - - - - 4,157 -

4 41,843 27.6 2,898 - - 3,674 35,271 -

6 21,694 14.3 248 - - 877 20,569 -

8 3,749 2.5 229 - - 3,520 -

Totals 151,704 100.0 4,422 - 36,437 110,848 -

2.3.3 Capacity Analysis

The hydraulic model for the RO system has not been completely calibrated due to lack of installed flow and pressure calibration data monitoring points. As a result, the RO model results have not been completely verified with actual field data and may not be fully accurate representation of the RO water system capacity and deficiencies. However, in the course of collecting data for the model, CH2M HILL staff has been able to obtain field information

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regarding RO system capacities and operating conditions. The major issues are low pressures, especially in the Commander’s Loop area. Figure 2-4 presents predicted hydraulic capacity problems from the RO model.

2.4 Water Quality

2.4.1 Federal and California Arsenic Rules

The USEPA has set a Federal Maximum Contaminant Level (MCL) of 10 µg/L (i.e. 10 parts per billion) for arsenic in drinking water. This arsenic standard was adopted on January 22, 2001, and became effective on February 22, 2002. The date by which systems must comply with the new standard was January 23, 2006. The Arsenic and Clarifications to Compliance and New Source Contaminants Monitoring Final Rule was published in the Federal Register (66 FR 6976) on January 22, 2001.

California Department of Health Services (DHS) will implement the Federal MCL and monitoring requirements. However, DHS does not have the authority to enforce the MCL until the state regulations have taken effect. If a violation should occur, DHS will notify USEPA, which can take enforcement action.

California State Law requires DHS to revise California’s arsenic MCL to comply with Federal standards. The state MCL cannot be less restrictive than the Federal MCL of 10 µg/L. The final California MCL for arsenic has not yet been announced. The state regulations are undergoing review and have not been subject to public comment yet. Since the state MCL cannot be less stringent than the Federal MCL, the state MCL will not be higher than 10 µg/L.

2.4.2 Fort Irwin Drinking Water Quality Goals

Goals for water quality at Fort Irwin include meeting all applicable primary and secondary water quality MCLs. The Fort Irwin-proposed water quality goal for arsenic is <8 µg/L, based on 80% of the Federal Primary MCL of 10 µg/L. The goal for fluoride is 0.6 to 0.8 mg/L, an optimal level per State of California, below the State Primary MCL of 2 mg/L (2003 Site Characterization Report for Fort Irwin, CH2M HILL, 2003). In addition, consumer acceptance of the distributed water may be gauged by monitoring constituents such as alkalinity, hardness, turbidity, and chlorine residual (CH2M HILL, 2003). Table 2-3 contains a listing of the water quality goals that have been used in developing the process design for the new WTP. Table 2-3 also shows which parameters are Primary and Secondary MCLs, and which are termed “consumer acceptance” goals.

0 1,000 2,000500 Feet

Figure 2-3 Existing RO Water Distribution System

Pressure Zone

Well

Tank

RO System

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5th Street

3rd Street

8th Street

G Ave nue

Rhin ela nd D riv e

Por k

Cho p

Hill Stre et

Land Fill Road

Nor m an dy

D riv e

4th Street

9th Street

7th Street

Langford Lake R oad

Salerno Drive

5th Street

B A ve nu e

5th Street

5th Street B A ve nu e

8th Street

Alvord Drive

South Lo op R oad

North Loop R oad

Goldstone Road

In ne r L oo p Roa d

Bar st ow R oa d

N orth Loop R oad

Bar st ow R oa d

R hin e la n d

D rive

So ut h Lo op R oa d

Inner Loop R oad

Figure 2-4 RO System Pressure Deficiencies

RO Deficiencies High Pressure (greater than 80 psi) Low Pressure (less than 30 psi)

Pressure Zone

Well Tank Existing PRV RO System

0 1,000 2,000500 Feet

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FIR_DRAFT REPORT - WATER DISTR. SYS. COMBI. STUDY_2AUG07_BMGG_REV14.DOC 2-13

TABLE 2-3

Fort Irwin Proposed Water Quality Goalsa

Parameter Goal Primary

MCL

Secondary

MCL

Consumer

Acceptance Comments Arsenic <8 µg/L X 80% of Primary Drinking Water

Standard of 10 µg/L

Fluoride 0.6 – 0.8 mg/L X Optimal level per State of California, below State Primary MCL of 2 mg/L

Nitrate <45 mg/L as NO3 X State Primary MCL

Ph 6.5-8.5 X Federal Secondary MCL

Iron <0.3 mg/L X State Secondary MCL

Total Dissolved Solids

< 500 mg/L X Recommended State Secondary

MCL

Color < 15 color units X State Secondary MCL

Taste and Odor TOD <3 X State Secondary MCL

Corrosivity LSI between 0 and +0.5

X Minimize corrosion potential of water

Alkalinity > 30 mg/L as CaCO3

X Promote stability of water quality in distribution system

Hardness 60-120 mg/L as CaCO3

X Maximize consumer acceptance of water

Turbidity <0.3 NTU X Maximize consumer acceptance of water

Chlorine Residual

0.5 – 1.0 mg/L X Provide secondary disinfection in distribution system while maximizing consumer acceptance of water a Based on Table 2-3 in 2003 Site Characterization Report for Fort Irwin (CH2M HILL, 2003)

The new water treatment system and water distribution system will be designed, operated, and maintained to accomplish these water quality goals. Meeting these water quality goals will continue to be a priority during and after the transition to a single water distribution system for all uses.

2.4.3 Water Quality Sampling of Distribution System

There are several locations where water sampling is routinely performed at Fort Irwin. Samples are taken of the source water at wells, booster stations, and storage tanks. Sampling is performed at the RO Drinking Water Treatment Facility influent and effluent after blending with the DO water. In addition, sampling is performed within the distribution system at different pressure zones on a rotating basis.

Table 2-4 includes a listing of all water quality monitoring performed within the distribution system. Water quality sampling has occurred according to the Fort Irwin Sampling and Analysis Plan (CH2M HILL, 2005) since September 2005.

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TABLE 2-4

Fort Irwin Water Distribution System Water Quality Monitoringa

Parameter Sample Frequency

Total Coliform 4 per zone per week (4 zones), rotating sites

Temperature 1 per zone per week (4 zones), rotating sites

Fluoride 1 per zone per week (4 zones), rotating sites

Bacteriological Quality and U.S. Army- Required Sampling

Corrosivity (including the parameters of pH, temperature, alkalinity, hardness, and TDS)

1 per zone per week (4 zones), rotating sites

Lead 30 samples every 3 years at select sites Lead and Copper Sampling

Copper 30 samples every 3 years at select sites

General Physical and Mineral Sampling

Bicarbonate, carbonate, and hydroxide alkalinity

Once every 3 years at all 13 sampling locations

Calcium, chloride, copper, corrosivity, iron, magnesium, silver, sodium, sulfate, total hardness, and zinc

Once every 3 years at all 13 sampling locations a Information from Fort Irwin Water System Sampling and Analysis Plan, September 12, 2005 (CH2M HILL, 2005)

Bacteriological quality and U.S. Army-required sampling occurs on a weekly basis rotating between 13 set sample sites throughout the distribution system. Each week, four locations are sampled. One location is sampled each week, and the other samples are drawn from the remaining 12 locations on a rotating basis. Each of these remaining 12 locations are sampled every fourth sampling event, an average of once per month. Parameters include coliforms, fluoride, chlorine, corrosivity, pH, temperature alkalinity, hardness, and total dissolved solids

(TDS).

Sampling for general mineral parameters occurs once every 3 years within the distribution system. Parameters include bicarbonate alkalinity, carbonate alkalinity, hydroxide alkalinity, calcium, chloride, copper, corrosivity, iron, magnesium, silver, sodium, sulfate, total hardness, and zinc. This sampling occurs at all 13 distribution system sampling locations.

Sampling for general physical parameters of color, foaming agents, odor, pH, specific conductance and TDS occurs monthly at all 13 distribution system sampling locations.

2.5 Regulatory Requirements and Applicable Standards for

Water System Improvements

2.5.1 State of California Domestic Water Supply Permit

The DHS issued a State of California Domestic Water Supply Permit to the United States Department of the Army for the Fort Irwin Water System (permit number 03-13-04(P)-001) on January 15, 2004. In this permit, DHS determined that the use of a dual piped system to deliver water to a community system for all domestic uses (including drinking) does not comply with

FIR_DRAFT REPORT - WATER DISTR. SYS. COMBI. STUDY_2AUG07_BMGG_REV14.DOC 2-15

the Water Works Standards (California Code of Regulations Title 22, Division 4, Chapter 16) and all applicable regulations. According to the permit, both existing RO and DO distribution systems at Fort Irwin are considered to provide potable water, the difference being that the RO system is in compliance and the DO system is not due to elevated levels of constituents such as arsenic and fluoride.

2.5.2 U.S. Army Regulations

As a Federal military installation, the water system at Fort Irwin is subject to Army regulations and review by Army agencies. The United States Army Center for Health Promotion and Preventive Medicine (USACHPPM) may conduct audits of the system and make recommendations to protect Army interests and personnel. CHPPM may also make recommendations for capital improvements or operations and maintenance.

2.5.3 Preparing a Distribution System for Compliant Potable Use Water from the existing DO water distribution system is potable as defined in the Fort Irwin water supply permit issued by DHS, though it is not in compliance with the water quality requirements of this permit. The existing DO water distribution system will become the “back-bone” of a single drinking water distribution system serving all uses at Fort Irwin. The transition of the DO and RO distribution systems from a dual water system to a single drinking water system requires preparation of the DO distribution system for drinking water use.

However, since the existing DO water is not in compliance, it is appropriate to apply industry standards and guidelines for transition of the DO distribution system to potable drinking water service.

A search was performed to find any regulations or standards applicable to the conversion of a water distribution system from non-compliant water to potable drinking water use. The State of California does not have regulations or standards covering this. Standards published by the American Water Works Association (AWWA) also do not contain information on the conversion of a non-compliant potable water distribution system to drinking water use.

There are no specific regulations and standards that describe converting a water distribution system from non-compliant water to compliant drinking water use. There are existing standards for the cleaning, flushing, and disinfecting of water systems in preparation for potable drinking water use. These are explained in the following section.

Specific recommendations for preparing the DO and RO water systems for conversion to a single drinking water system are presented in Section 6, Transition Plan.

2.5.4 Cleaning, Flushing, and Disinfecting Water Systems for Drinking Water Use

CH2M HILL

CH2M HILL’s Fort Irwin Water and Wastewater Design and Construction Standards contains Section 02519 on Disinfection of Water Systems. This section references other standards, including those of the AWWA and Standard Methods for the Examination of Water and Wastewater (American Public Health Association [AWWA] and the Water Environment Federation [WEF]).

U.S. Army Corps of Engineers Engineer Manual (EM) EM 1110-3-164 (April 1984), titled Water Supply, Water Distribution, contains basic information on design and construction of water

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distribution systems at U.S. Army installations. The manual also contains some information related to the cleaning and flushing of water mains.

State of California Title 22 Division 4 (Environmental Health) of the California Code of Regulations (CCR) contains regulations related to drinking water (dated June 2004). Chapter 16 (California Waterworks Standards) of Division 4 includes Article 5, Water Mains and Appurtenances. This Article describes how water mains shall be disinfected according to AWWA Standard C601-81 (replaced by C651-05 in 2005), titled Disinfection of Water Mains.

American Water Works Association Several AWWA standards discuss the disinfection of water mains, water storage facilities, water treatment plants, and wells. The list below presents applicable AWWA standards for disinfection of water treatment and distribution system components:

• ANSI/AWWA C651-05 Disinfecting Water Mains

• ANSI/AWWA C652-02 Disinfection of Water Storage Facilities

• ANSI/AWWA C653-03 Disinfection of Water Treatment Plants

• ANSI/AWWA C654-03 Disinfection of Wells

Other references that provide helpful information are:

• ANSI/AWWA G200-04 Distribution Systems Operation and Management

• AWWA M14 Recommended Practice for Backflow Prevention and Cross-Connection Control

• AWWA M28 Rehabilitation of Water Mains (2001)

• California-Nevada Section of AWWA Distribution Main Flushing and Cleaning Manual #3 Prepared by System Water Quality Committee, California-Nevada Section (AWWA, November 16, 1981)

• Guidance Manual for Monitoring Distribution System Water Quality (AWWA, 2002)

FIR_DRAFT REPORT - WATER DISTR. SYS. COMBI. STUDY_2AUG07_BMGG_REV14.DOC 3-1

SECTION 3.0

Proposed Capital Projects

3.1 Capital Improvement Projects (Years 2006 through 2008)

CH2M HILL's 2007 Annual Capital Improvement Plan includes many water system capital improvement projects recommended to be completed in addition to the conversion of the DO and RO water system to a single drinking water system. The following water system capital improvement projects are scheduled to be completed during the next three Contract Years (April 1, 2007 through March 31, 2010):

• W4 – New Water Treatment Plant

• W9 – Install Water Meters

• W10 – Replace Underground Tank

• W11 – Bicycle Lake/Irwin Basin Transmission Pipeline

• W13 – Install Domestic Water System PRVs

• W15 – Clean and Inspect Water Reservoirs

• W20 – Recondition and Upgrade Water Production Wells

• W21 – Water System Master Plan

• W22 – Water Supply and Distribution Expansion Phase 1

• W23 – Water Supply and Distribution Expansion Phase 2

Detailed project descriptions are included in the Final Submittal, 2007 Annual Plan - Part 2: 2007 Capital Improvement Plan for the Privatization of Water and Wastewater Utility Systems, Fort Irwin, California (CH2M HILL, February 2007).

3.2 Required Projects for Single Water System Combination

This section describes three major CIP projects required to convert the dual water system into a single drinking water system. The three projects include: W4, New Water Treatment Plant; W10, Replace Underground Tank; and W11, Bicycle Lake Water Main to WTP. Project descriptions for each proposed project are summarized in the following section.

3.2.1 New Water Treatment Plant (CIP Project W4)

The new electro dialysis reversal (EDR) water treatment plant (WTP) will be constructed with an initial capacity of 6 mgd, expandable to 12 mgd. The WTP will be located southwest of the intersection of Goldstone Road and North Loop Road. The plant will be capable of removing arsenic, fluoride and many other regulated contaminants, similar to the RO plant.

3.2.2 New Treated Water Storage Tank (CIP Project W10)

The existing underground storage tank in the DO system is unsuitable for use in drinking water service because it has a creosote-impregnated wooden roof. A new above-ground 1-MG treated water storage tank will be constructed on the WTP site. This tank will replace the existing 1-MG

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underground storage tank and supplement the JPL 1, JPL 2 and JPL 3 storage tanks to retain a total treated water storage capacity of 4 MG. It will have a pumped discharge, delivering water to the higher JPL 2 and JPL 3 tanks and the higher pressure zones within the Cantonment.

3.2.3 Bicycle Lake/Irwin Basin Transmission Pipeline (CIP Project W11) As discussed in Section 2, the Bicycle Lake and Irwin wells currently supply water directly to the distribution system via the 16-inch water line that runs through the Cantonment to the JPL storage tanks. In order for treated water only to be delivered to the distribution system, a separate untreated water supply line must be constructed to convey Bicycle Lake and Irwin well water directly to the new WTP. The new Bicycle Lake/Irwin Basin Transmission Pipeline will create a defined flow path for untreated groundwater from the wells to the new WTP without being connected to the treated water distribution system.

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SECTION 4.0

Single Water System Configuration Hydraulic Evaluation

4.1 Key Design Criteria

This section summarizes key design criteria and assumptions used to evaluate the water distribution systems’ capacity for conversion to a single water system.

4.1.1 Hydraulic Model

The water distribution system capacities were analyzed using updated static hydraulic models developed for the 2003 Project Characterization Report. The models were revised to reflect Year 2007 operating conditions.