FIBERGLASS UNDERGROUND STORAGE TANKS POTABLE WATER Š FIRE CISTERNS Š RAIN CAPTURE WASTEWATER TREATMENT Š LANDSCAPE IRRIGATION STORMWATER DETENTION Š KINETIC WATER FEATURES Application & Installation Information

Phone: (800) 232-8660 Š Fax: (303) 644-5001 Internet: www.darcoinc.com Š E-mail: [email protected].

FIBERGLASS TANK INSTALLATION MANUAL The following information deals only with the installation of FIBERGLASS water storage tanks distributed & warranted by Darco Incorporated, Bennett Colorado. Written by: John Small Darco, Inc. AutoCAD Drafting by: Jeff Sagerman / Darco Inc. Illustrations and layout by: Kim Seipp / High Plains Graphics Terrye Hoffman / Prairie Skies Technical Services, LLC FRPMAN 8 Latest revision date: September, 2007 To contact Darco Inc: Phone Toll Free 1- 800-232- 8660 Fax 1-303-644-5001 Mail (payments and invoices): Darco Inc. P.O. Box 779 Bennett, Colorado 80102 Ship to (manufacturing facility): Darco Inc. 980 Darco Drive Bennett, Colorado 80102 The following information is written and illustrated in a non-technical manner in an attempt to make the Owner of our products aware of the installation procedure. He should understand the basic site and design related decisions that he or his engineer and installing contractor must make. We feel it is critical that the Owner have sufficient knowledge of this process to enable him to monitor or direct the installation of our products to his ultimate satisfaction.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

Bureau of Land Management - Moab, Utah © 2007 DARCO, INC – ALL RIGHTS RESERVED

FRP TANK INSTALLATION INDEX BY TOPIC AND PAGE INTRODUCTION

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A FEW WORDS ABOUT WATER TODAY ........................................................ 1 APPLICATIONS FOR AND THE ADVANTAGES OF FRP TANKS .................. 3 DELIVERY AND INSPECTION ......................................................................... 4 HANDLING AND STORING FIBERGLASS TANKS.......................................... 6 TANK BEDDING AND BACKFILL MATERIAL .................................................. 8 BASIC DESIGN LAYOUTS ............................................................................. 11 SELECTING THE BEST SITE TO INSTALL YOUR SYSTEM ........................ 14 HOLE SIZE AND WORKING CLEARANCE FOR BACKFILL ......................... 16 DEADMEN, SLAB ANCHORS, AND BED UNDER DRAINS .......................... 17 TRAFFIC SLABS FOR AUTOS AND TRUCKS .............................................. 23 NON-TRAFFIC BEARING SLABS .................................................................. 24 BURIAL DEPTH, VENT ICING, AND INSULATION ........................................ 24 PROPER VENTING DETAILS ........................................................................ 26 MOUNDED BURIAL ABOVE SPRING LINE ................................................... 27 COMMON TANK ACCESSORIES AS SEEN IN ILLUSTRATIONS ................ 28 Manway Extensions ..................................................................................... 29 Manway Enclosures ..................................................................................... 29 Tank Fittings for Pipeline Connections......................................................... 29 Inspection Hatches ...................................................................................... 29 Water Level Gauges .................................................................................... 31 Float Valves ................................................................................................. 31 Quick Disconnects ....................................................................................... 32 Inlet Filters ................................................................................................... 33 Overflow Piping ............................................................................................ 33 High Water Level Control ............................................................................. 34 Flexible Tank-to-Pipeline Couplings ............................................................ 35 Submersible Pump Mounting Platforms ....................................................... 37 Rural Suction Dry Fire Hydrants or City Style Dry Barrel Hydrants .............. 37 Custom Made Accessories .......................................................................... 38

© 2007 DARCO, INC – ALL RIGHTS RESERVED

INSTALLATION

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DIGGING A HOLE AND GETTING THE PROJECT STARTED ...................... 39 OPTIONAL WATER BALLAST FOR TANK STABILITY.................................. 39 TANK DEFLECTION MEASUREMENTS ........................................................ 42 HYDROSTATIC LEAK TESTING .................................................................... 43 GEOTEXTILE FILTER FABRIC ...................................................................... 43 PVC PIPING .................................................................................................... 44 UNRESTRAINED MECHANICAL COMPRESSION JOINTS (MJs) ................ 45 POTABLE WATER OR "DRINKING WATER" TANK ISSUES ........................ 45 FIRE CISTERN ISSUES ................................................................................. 46 SEPTIC TANK ISSUES................................................................................... 49 SAFETY ISSUES ............................................................................................ 50 CONTRACTOR'S QUICK CHECK INSTALLATION PROCEDURE ................ 51 WARRANTY DETAILS .................................................................................... 53 TANK PURCHASE GUIDE SPECIFICATION ................................................. 55 CUSTOMER COMMENTS AND INSTALLATION EXPERIENCES ................ 57 DRAWINGS

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Fiberglass Tank Product Line Part 1 ............................................................................................. 60 Fiberglass Tank Product Line Part 2 ............................................................................................. 61 Flex Couplers 1.............................................................................................................................. 62 Flex Couplers 2.............................................................................................................................. 63 Overflows ....................................................................................................................................... 64 Float Valve High Level Control ...................................................................................................... 65 Inlet Filter For Well Water .............................................................................................................. 66 Fire Cistern Concepts #1 ............................................................................................................... 67 Fire Cistern Concepts #2 ............................................................................................................... 68 Fire Cistern Concepts #3 ............................................................................................................... 69 Fire Cistern Concepts (Suction) .................................................................................................... 70 Fire Sprinkler Reservoir ................................................................................................................. 71 Fire Apparatus Pump Test Station ................................................................................................ 72 Manway Information 1 ................................................................................................................... 73 Manway Information 2 ................................................................................................................... 74 Manway Information 3 ................................................................................................................... 75 Manway Information 4 ................................................................................................................... 76 Submersible Pump With Float Controls ........................................................................................ 77 Float Switch Tree in Manway ........................................................................................................ 78 Jet Pump in Manway Vault ............................................................................................................ 79 Potable Water Treatment & Delivery System ................................................................................ 80 Wet Well Delivery System ............................................................................................................. 81 Insulated Underground Tanks ....................................................................................................... 82 H-20 Traffic Slab Details ................................................................................................................ 83 Crested Butte Installation Photos .................................................................................................. 84

© 2007 DARCO, INC – ALL RIGHTS RESERVED

© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N A FEW WORDS ABOUT WATER TODAY As we are all aware, the quality, and in many cases the quantity, of our drinking water supply is becoming a daily topic of discussion. 30 years ago, nobody gave it a thought - - - so what's happening? As population grows, more of us rely on fresh water supplies every day, and our culture is slowly changing. Most urban American adults take at least one shower every day. Those of us who desire to live outside the city will require more wells and septic systems every year. Commercial farming is increasing the use of high powered chemicals and fertilizers. Industrial waste is becoming more difficult to dispose of safely. High tech water analysis equipment can now easily detect water pollution in parts per billion. Our federal government has created the "Safe Drinking Water Act" which is costing all of us tax dollars as we clean up past problems and better protect our future environment. We turn our noses up when tap water smells of chlorine, even though chlorination is probably the one greatest boon to public health in the last century. Trendy bottled drinking water costs more than gasoline, and we pay without a whimper. The concept of recycling or stepped use of fresh water resources is becoming a reality. The irrigation of city parks and golf courses is now often done with partially treated wastewater to avoid the unnecessary cost of water treatment to drinking water standards. Many rural western families living in semi-arid areas save filtered gray water from their washing machines and gutters for irrigation of trees and flowers. This helps reduce the load on their wells and septic systems. We now seem to want control or choice of everything we eat and drink; "Certified Organic" vegetables, "Free Range" poultry, "Steroid Free" meats, and water "Polished" at the point of use, by a little filter gizmo hidden below our own kitchen counter. We think nothing of taking our personal water to a restaurant in a plastic sport bottle. When I see this sort of thing, I keep thinking I must be in some undeveloped country - not Denver Colorado, home base for the "American Water Works Association". We Americans are starting to seriously decentralize after more than 100 years of centralization. People today really aren't too sure about that big building downtown that treats millions of gallons of goop out of the river, and then sends it through questionable pipes to you know who. Is it safe to drink? - - yes, beyond a doubt. Does it always taste and smell like Rocky Mountain spring water? - - probably not. Are the costs of collecting, treating, and transporting domestic potable water and wastewater increasing? - - yes, in many cases dramatically. As a result, many large industrial manufacturers and commercial agricultural processors are taking control of these escalating costs by investing in their own water and wastewater processing equipment - and in so, further decentralizing. © 2007 DARCO, INC – ALL RIGHTS RESERVED

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Shopping centers and office parks are being built miles away from the nearest city water line or sewer. Many urban families yearn to move 15 miles outside town, or even to go "off grid" and be totally self sufficient. This expanding new decentralization movement is possible due in part to recent technological advances dealing with small scale treatment and storage of drinking water, solar and wind power generation, and efficient on site wastewater treatment. Such technologies are increasingly more attractive and practical as the cost of centralized municipal infrastructure creeps ever upward. A common component in several of these new technologies is the storage of water and waste in high quality, long life, corrosion proof, fiberglass (FRP) tanks. We are all familiar with central water system storage tanks located on the tops of hills around most cities or on ugly elevated steel towers. Most private or decentralized potable water systems incorporate storage tanks as well, but you rarely see them. Since the capacity required is much smaller, you will find water storage systems buried below landscaped greenbelts and below auto parking lots, out of site underground, where it remains cool and safe. Our resilient economy and attractive interest rates over the past 20 plus years have allowed many commercial businesses and manufacturers to move away from big cities to a more peaceful rural environment. Such decentralization has its drawbacks or tradeoffs, particularly in the area of fire protection. The high volume fire fighting water flows required for life safety and fire insurance coverage are generally unavailable directly from the water wells serving such establishments. As a result, a storage reservoir is required for fire sprinklers and mobile fire suppression apparatus based on NFPA (National Fire Protection Association) standards. Fiberglass fire cisterns are commonly installed to provide such a water source for both hard piped sprinkler systems and trucks. Domestic potable water may also be stored in a similar underground fiberglass vessel. Small volumes of well water are continuously collected, treated, and stored for the upcoming day's needs. Wastewater must be treated and returned to the ground through a septic system, constructed wetland, or similar approved process. Again, large underground fiberglass tanks properly engineered for wastewater treatment are a cost effective, long life, environmentally friendly choice where municipal sewer lines may not be practical. Underground fiberglass vessels are available from Darco in capacities ranging from 15,000 gallons to 75,000 gallons with diameters of 8, 10, 12 & 13 feet. Several tanks may be effectively manifolded together to create a larger storage system as necessary. Large multi-tank designs are very cost effective when compared to concrete tanks in the 50,000 to 250,000 gallon range, particularly if the site is remote and the concrete must be transported long distances.

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N APPLICATIONS FOR AND THE ADVANTAGES OF FRP TANKS 20 REASONS WHY A DARCO FIBERGLASS (FRP) UNDERGROUND WATER STORAGE SYSTEM SHOULD BE THE FIRST CHOICE TO MEET YOUR DRINKING WATER, WASTEWATER, AND FIRE PROTECTION WATER NEEDS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.

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FRP tanks are manufactured from a “food contact” grade fiberglass resin and are safe for the temporary storage of drinking water (potable water). Properly buried water tanks won't freeze - no worries about insulation and electrical heating, even in high mountain areas and northern states. Underground water temperatures average about 50 degrees - an environment less likely to support the growth of algae or bacteria. Steel tanks will eventually rust and corrode. With or without protective coatings, it is just a matter of time - FRP tanks will never rust or corrode. Underground tanks with lockable hatches are safe - out of site and out of mind less likely to be vandalized or create an "attractive nuisance." You may purchase FRP tanks directly from Darco Inc. in Bennett, Colorado FRP tanks can be cost effectively truck shipped from coast to coast in the continental United States or by sea to remote off shore installation sites. FRP tanks meet the basic National Fire Protection Association 1142 and NFPA 22 structural design, storage capacity, and fire flow requirements. FRP tanks make excellent single and multiple compartment septic tanks or sewage vaults, but must have prior approval from the local Dept. of Health Large multiple tank systems can be arranged in any pattern necessary to meet a required excavation footprint - "L" shaped for instance. All Darco fiberglass tanks are pressure and vacuum tested when made, so there is no need for dangerous on site pressure testing prior to installation. FRP tanks are less expensive per gallon compared to drinking water quality reinforced concrete tanks in the 50,000 to 250,000 gallon size range. FRP tanks may be bedded and backfilled with common pea gravel or chips. Fiberglass tanks are light in weight and easy to move and position on site. FRP tanks will withstand the weight of automobiles and trucks when properly installed beneath an approved concrete traffic slab on grade. Concrete tanks will eventually hairline crack and leak to some degree - this also means that untreated groundwater may be infiltrating from outside. You can haul a 15,000 gallon tank by flat bed trailer behind a 1-ton pick-up. Systems may be set up with compartmentalized or baffled chambers, such as a 20,000 gallon tank incorporating one 6000 gallon drinking water compartment unconnected to 14,000 gallons ready for fire protection. FRP cisterns meet NFPA 299 rural fire fighting flow standards often required for homeowner insurance coverage in remote forested areas. For an additional fee, job specific tank designs may be approved and sealed by our Professional Underground Tank Engineer, retained by Darco Inc.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N DELIVERY AND INSPECTION It is the responsibility of the Owner or his contractor to inspect each tank while on the delivery trailer for any signs of damage before signing the driver's delivery paperwork. Take possession and offload only after you are comfortable with the condition of your new tank. Be particularly careful to inspect for serious abrasions or scars along the bottom, possibly caused by contact with the delivery trailer bed. Minor scuffing and surface scratches should not be a source of concern. In the unlikely event you do find freight damage, make careful notation in the appropriate place on the shipping paperwork. Have our driver inspect the damage, and put his signature with date by your written statement. If possible, hold the truck on the site while you call Darco or your tank dealer for further instructions. 1. Fiberglass tanks should only be lifted from above using accepted rigging procedures and lifting angles as illustrated on the following pages. 2. Use a crane for lifting large tanks rather than attempting to use earthmoving equipment such as a track hoe or large wheel loader. 3. Attach to all designated lifting lugs with equal length slings and shackles for proper load distribution. Safety wire chain hooks if shackles are not used. 4. If you must use a track hoe, be certain you have enough vertical reach to maintain the desired 60 degree included lifting angle on all rigging as illustrated. A spreader beam will simplify rigging in such cases due to limited bucket height. Working from the top of a ramped soil mound can also increase total lift height. 5. If you have no other choice and must use a large front loader, bolt two heavy I-beam lifting stingers into the bucket corners to simplify rigging and to avoid any possible contact between the tank and teeth, when curled. 6. Do not lift any fiberglass tank from below with forks. 7. Do not lift with chains or steel cables wrapped around the body of the tank. 8. Never pressure test any tank on site without an approved testing manifold. It is also the responsibility of the Owner to coordinate the delivery of his tank by providing a detailed local map or pilot car to direct our truck driver to the job site. Consider the width, height, length when routing and be sure the driver can turn around easily once unloaded. The owner is expected to have adequate manpower, a 20 foot extension ladder, rigging gear, and lifting equipment to unload the delivery vehicle in a safe and timely manner. Deliveries must be made on or near a publicly maintained roadway. Delivery drivers are instructed not to enter any local or private road which may possibly damage his equipment, create a hazard, or cause him a delay of any kind.

IMPORTANT – Do not expect our delivery driver to "off-road" or take chances with his tractor-trailer for your convenience - Plan ahead, please be ready !

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N WARNING – Do not air pressure test without a factory approved testing manifold, which includes pressure relief and accurate low pressure gauging.

HANDLING AND STORING FIBERGLASS TANKS If a tank must be stored on site for a few days prior to installation, it must be placed on a flat soil area for uniform support along the entire bottom. Chock it into place with rubber tires and consider lashing the tank down as illustrated if high winds are possible. Use several opposing guide ropes to control the tank while it is in the air and never walk under or ride on a tank while being positioned.

WARNING – All 8 foot through 12 foot diameter Darco fiberglass tanks have the same 6 lift lug configuration and rigging procedure. Fiberglass tanks must be picked off the delivery trailer with one set of 4 lugs and then placed on the ground in a flat, rock free area. They are then rotated to the proper vertical position and repicked with a different combination of 4 lugs for final positioning in the open hole.

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N Tanks should not be rolled any distance or skidded, and should not be placed on top of rough frozen ground or frozen gravel. If the bedding material is icy or covered with snow, remove the snow and break up the frozen gravel to avoid point loading the vessel when positioned. Lifting lugs are designed for empty tank weight only. If you must use a secondary trailer to transport your tank from the Darco delivery point into a remote or difficult to reach job site, be sure this secondary trailer offers full belly support under the entire length of the vessel. Use numerous old rubber tires on the trailer deck to help cushion the tank and to avoid point load damage to the ribs.

TANK BEDDING AND BACKFILL MATERIAL A 30,000 gallon tanks holds over 100 tons of water. It doesn't take much imagination to consider the catastrophic results of incorrectly supporting the belly of such a vessel with improper backfill material or installation technique. Specified backfill is used to replace the native soil below, along side, and over the entire vessel to guarantee that the tank is solidly supported and totally "encapsulated" in a homogeneous gravel medium. This dry gravel material must be shoveled into place and then probed to 95% density without trapping air pockets or void spaces. Native soil containing clay clods or silty fines is virtually impossible to compact uniformly and lacks the ability to flow properly when probed beneath the vessel. Hand probing (not violent tamping) is required to consolidate the select supporting gravel backfill under any fiberglass tank. The result of using improper backfill material or improper probing technique is tank distortion and settling which may cause tank fitting cracks and pipeline leaks. Your warranty is based on the use of proper backfill materials and conscientious but gentle hand probing as illustrated.

IMPORTANT Approved Backfill: 1. May be "pea" gravel ranging from approximately1/8 to 1/2 inch diameter. 2. May be crushed rock or chips ranging from 1/4 to 1/2 inch screen size. 3. May be a substitute material if approved in writing before installation. 4. 1 thru 3 above must have no individual particles or stones over 1/2 inch size. 5. 1 thru 3 must be dry and free of ice, snow, and debris. 6. 1 thru 3 must be sound, weigh at least 100 pounds per cubic foot, and be washed and classified so that no more than 5% will pass through a #8 sieve.

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

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Ramped loader access with benched side walls

WARNING – Follow OSHA 1926.650/P safety guidelines for pipeline trenching and tank hole excavation. Back slope or bench the sidewalls for safety while working in the hole to place and probe gravel backfill below the tank

IMPORTANT – Do not attempt to use low cost unsatisfactory generic or non-spec materials often identified by slang names such as: road base, squeegee, structural fill, or crusher fines. If you have questions as to the suitability of any potential backfill material, contact your tank supplier or Darco before performing the installation. A sieve analysis or small sample of your proposed substitute material may be requested when you ask for our approval to deviate from the specification. The backfill material used when installing our polyethylene tanks is not identical to the fiberglass installation requirements. Be sure when you download Darco Installation Instructions that they are for the correct type of vessel you are preparing to install (fiberglass or polyethylene).

IMPORTANT – Tanks must be completely bedded, surrounded, and covered with gravel and hand probed to 95% density to avoid air pockets or void spaces. No soil may be replaced between the freshly cut side walls of the hole, as illustrated. Geotextile fabric is recommended as a separation membrane to eliminate migration between dissimilar cover materials. 10

© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N BASIC DESIGN LAYOUTS Underground tank installations generally fall into one of the 3 categories: Full Bury, Side Hill, or Mounded Bury. Common bury depths range from 1 to 4 feet of cover depending on the amount of sub-zero winter weather traditionally expected. Tank installations may be insulated to reduce this bury depth when desirable. Typically 3 feet of soil cover is adequate for an ice free installation across the northern states unless weather conditions are severe. The minimum soil cover in warm southern states is 1 foot. 1. FULL BURY installations should be slightly mounded to divert surface water from saturating the gravel bed. If seasonal high ground water or perched water is probable, we strongly recommend that concrete deadman anchors be installed to avoid possible floatation of partially empty tanks.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N 2. SIDE HILL installations require that no less than the bottom half of the tank be captured in a pocket of undisturbed natural soil for proper support. If high ground water or perched water is probable, install a “sub-drain” or bed drain running down hill to daylight to relieve any water trapped in the tank bedding material.

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© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N 3. MOUNDED BURY installations also require that no less than half the tank be placed below the undisturbed natural grade for proper support. Mechanically anchoring tanks in mounded applications is not entirely effective due to the lack of material above the tank and the resulting limited down force to counteract buoyancy.

IMPORTANT – Never add previously excavated soil behind specified backfill to reduce the amount of gravel necessary or to save money. The tank walls and end heads must bear directly on clean gravel which then bears directly on the soil of the undisturbed walls in the hole. Any replaced soil between the tank and the side walls will compress and subside over time leaving the tank unsupported and vulnerable to distortion and stress. In wide angle excavations where the side walls will not stand or continuously slough off, cut the 4 walls back severely. Probe and mound backfill gravel below and over the tank to the backfill material’s natural angle of repose. Finish by covering with geotextile fabric and then replacing the soil cover to a slightly mounded grade. Follow the same backfill process when using a dozer or loader to cut the hole incorporating shallow angle entry or exit ramps as illustrated.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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SELECTING THE BEST SITE TO INSTALL YOUR SYSTEM Underground storage tanks can be installed to discharge water by gravity or pump, based on whether the tank is located above or below the elevation of intended water use. It is often beneficial to bury a UST (Underground Storage Tank) into a hillside or on a knoll above the point of use. If this vertical distance is sufficient, considerable static water pressure can be generated. Water exerts a force of .43 pounds of pressure (psi) per foot of elevation. If you were to install a storage tank 80 feet above your home, you would develop approximately 35 pounds of static pressure in the water system. You must however, deduct the friction loss or pressure drop caused by the water moving through the pipelines. Low pressure gravity flow systems function best when piping runs are short and the pipeline diameters are relatively large, thereby reducing such friction loss pressure drop to a minimum. Fire protection cisterns are often set up for discharge slightly downhill to a fire hydrant. Just a few feet of drop between the tank bottom and the hydrant creates sufficient pressure to force water directly into the fire truck pump when the hydrant is opened. Flooding the suction inlet eliminates the need to vacuum prime the fire pump. This may save precious minutes for Firefighters working in the dark on a cold December night. Design gravity flow systems with large diameter short run discharge piping in mind. Sucking water vertically up out of a buried cistern or pond is called “drafting" and becomes increasingly more difficult for any water pump as this vertical lift exceeds 10 feet. Always design such draft water supply systems with minimum vertical water lift in mind. 14

© 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N

When underground storage tanks are located in flat level areas, several critical issues should be taken into consideration. If there is any possibility that a heavy vehicle could drive over your tank, erect a fence or barricade. If you wish to install a driveway over the storage tank, you will need to construct an approved concrete traffic slab to properly distribute and bridge the vehicle weight over your tank. Rain water should never be allowed to pool and saturate the tank burial site. Mound soil slightly over the tank to compensate for settling over time. Channel surface water away from the site, and seed grass to retard erosion. In areas with the potential for occasional high ground water, it is advisable to anchor FRP tanks down to approved concrete deadman. Unanchored empty tanks can actually float right out of the ground due to unusually wet soil conditions. The decision to use an anchor system should be made by a person who is familiar with the soil conditions and seasonal water table at your specific site. When in doubt about the groundwater level, dig an inspection hole or consult a geotechnical professional. Under normal conditions, a deadman anchor system will be adequate. In well-drained soils or dry Western states, anchoring is rarely necessary.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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HOLE SIZE AND WORKING CLEARANCE FOR BACKFILL 1. Allow for 12 inches of bedding material below each vessel. 2. Allow a minimum of 18 inches from the tank to the excavation walls. 3. Allow 18 inches between individual tanks set side-by-side or end-to-end. (tank to tank clearance must be increased when using deadman anchors) 4. Follow OSHA 1926.650/P excavation safety guidelines when installing tanks.

IMPORTANT – The following is a list of physical conditions that are not suitable for standard FRP tank installations. Additional consideration and special attention must be given to these conditions or your warranty may become void. If you have any doubts or questions about a proposed installation site, call Darco for preliminary assistance at 800-232-8660. 1. 2. 3. 4. 5. 6. 7. 16

Unstable soil, defined as having a load bearing capacity of less than 2000 pounds / square ft. or a cohesion value of less than 500 pounds / square ft. Surface auto or truck traffic without an approved concrete slab on grade. Locations suspect of being totally saturated during the rainy or wet season. Marshy or tidal conditions. Landfill sites of any type. Wet holes (water encountered during excavation). Hydro-compactive or hydro-expansive soils (Bentonite is hydro-expansive). © 2007 DARCO, INC – ALL RIGHTS RESERVED

I N T R O D U C T I O N 8. 9.

Probable flood plains along the banks of creeks, rivers, or lakes. Storage of hot water above 150 degrees Fahrenheit (such as generated by solar heat systems, process cooling water, or geothermal springs). 10. Unapproved structural tank modifications. 11. Use above ground without proper support and structural design approval. 12. Storage of liquids or materials other than water.

WARNING – Darco neither permits nor approves the use of our FRP tank systems to store any liquid other than water or water based domestic sewage without prior project review and specific written approval. Under no circumstances are tanks to be used for the storage of waste oil, motor fuels, process chemicals, or potentially hazardous materials of any type.

DEADMEN, SLAB ANCHORS, AND BED UNDER DRAINS If you have concerns that your water storage system may be subject to ground water at some time in the future or if you expect the tanks to be low on water for extended periods, you may wish to install an anchor system. Whenever possible, keep your underground tank full rather than empty. Another simple way to guard against possible floatation is to locate your system in such a way that the gravel bedding under the tank can be automatically drained of any accumulated water. This will require that the tank be located on the side of a hill, near a ravine. Any water building up under the tank can then be collected in fabric covered perforated piping and directed downhill by gravity to a daylight discharge. This sub-drain or French drain concept can also be accomplished with a remote water collection pit and an electric sump pump, but at greater expense and at the risk of power failures.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N Deadman anchors are solid concrete castings of the appropriate size, reinforced with multiple full length #5 rebars as illustrated. Deadmen are suitable for any standard installation where the ground water level will not rise higher than the “spring line” or center of the tank . Each deadman must be secured to 2 or more anchor straps and must pull downward on the tank in an even and balanced manner. Most tanks will require multiple deadmen along each side, laid end to end. These concrete anchors are easily poured in cardboard or wooden forms, or in special half round fiberglass forms available from Darco with your tank order. Determine the individual deadman lengths from your tank drawing and consider the lifting weight of each anchor you pour. Have the deadmen ready in advance so you can use a crane to set both your tank and the anchors into the hole on the same day. Position and wire the rebar into each form as illustrated. Insert several rebar loops sticking out the top for easy handling with chains. Allow deadmen to cure for several days and then carefully lift them at 2 balanced points to avoid cracking the green concrete. Position each deadman in the hole slightly beyond the tank major diameter, as illustrated. Check your tank drawing to confirm all the fiberglass straps are properly located for each specific Darco tank size. Hand tension 1/2 inch solid core 6 x 19 galvanized wire rope straight down from each anchor strap eyelet and around the deadman below. Once all the tie-down cables are single clamped into place, go back over each assembly for a second time to remove all slack using your anchor strap tensioning tool. Steel anchor cables require 3 clamps at every overlapping connection when tensioning is completed.

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I N T R O D U C T I O N

IMPORTANT – Follow the installation instructions regarding Darco Fiberglass Anchor Straps, Darco “Half Round” Fiberglass Deadman Forms, and the Darco Anchor Strap Tensioning Tool provided with your anchor strap order. A full slab anchor rather than deadmen is appropriate and advisable under the following general conditions: 1. Severe predictable or constant high groundwater conditions where the ground water rises above the center or “spring line” of the vessel 2. Soil bearing is marginal (less than 2000 pounds per square foot) 3. Landfill applications where subsidence may occur with time 4. Clay soils that expand or contract radically as their moisture level changes 5. Active seismic areas 6. The tank must be located in a riparian area near a lake or in a river flood plain Such under slabs are heavily reinforced, 12 inch thick concrete monoliths which extend outward beyond the tank perimeter on all 4 sides as specified. Anchoring Lugs are cast into the slab and slide over the internal steel reinforcing bars to create an anchor point for each strap as illustrated. The cable tie-down procedure and soil cover requirements are the same as with a deadman anchor system. Please refer to the appropriate illustrations and charts for the correct component sizes and proper bury depth for either style anchor system.

© 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N IMPORTANT – For proper anchoring down force, the effective minimum tank bury depth must be correct. This depth must be maintained over the entire excavation area. In addition, if a mounded soil cover is used, extend this mounded depth outward to the sides at least 5 additional feet beyond the deadmen or slab anchor.

TRAFFIC SLABS FOR AUTOS AND TRUCKS As a rule, we discourage locating an underground tank system where it will be subject to vehicle traffic. When there is no alternative, a properly reinforced concrete traffic slab must be poured above the tank to distribute and bridge the extra vehicle weight. No previously excavated soil may be used between the tank and the surface slab. 100% specified material must be applied to meet or exceed the minimum 16” depth from the top of the tank to the bottom of the slab. Manhole access covers poured into the slab must be isolated from direct contact with fitting risers or a rigid fiberglass manway access extension. Set manhole rings in a slightly raised area to avoid surface water pooling and seepage into the tank bedding past the iron cover. The slab over the tank area must be poured 8 inches thick, be properly cured, and incorporate 2 opposing layers of #5 rebar on 16 inch centers. The rebar layers must be centered vertically in the slab and lay perpendicular to each other forming a "mat" configuration. This heavily reinforced surface slab must extend 3 feet beyond the tank perimeter where it passes above the storage tank as illustrated. Do not use insulation board of any type between the tank and a traffic slab. © 2007 DARCO, INC – ALL RIGHTS RESERVED

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IMPORTANT – This concrete traffic slab information may be confusing or incomplete for your job. Please call Darco to review your slab design if you have questions.

NON-TRAFFIC BEARING SLABS When an FRP tank system must be buried beneath a concrete surface that will not need to support the weight of vehicles, the slab requirements are reduced. The select backfill process remains the same as for a traffic surface, however the concrete thickness and reinforcement requirements can be reduced to meet the non-traffic loads anticipated.

WARNING – Never install any tank directly below or near a load bearing foundation wall, footing, or caisson.

BURIAL DEPTH, VENT ICING, AND INSULATION Northern climates with frost reaching over 3 feet deep can cause tank icing problems. Properly insulating your tank and any shallow piping is always advisable. Extruded polystyrene foam board insulation specifically designed for underground use is your best insurance against tank surface icing and pipeline freeze-up. FRP tanks can tolerate some minor icing so long as the vent pipe is not frozen and blocked. A plugged or frozen vent line can cause an internal vacuum to form during 24

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I N T R O D U C T I O N rapid water discharge and may lead to structural tank damage. Adjust the water supply level control device to maintain several inches of air space at the top of each vessel as illustrated. In some applications you may want to install a high level overflow pipe to maintain an adequate air space and prevent water from ever freezing in the vertical pipe risers. Our recommended procedure in sub-zero climates is to insulate above the entire excavated area with 2 inch thick underground rated board insulation, followed by 2 feet of soil cover to grade, plus an additional 12 inches of mounded soil above grade. This standard insulated design is based on 36 inches of total soil cover plus 2 inches of the proper board insulation and has proven to be effective in northern climates. A deeper bury depth plus additional layers of foam board insulation may be applied when conditions are extreme. If you are in doubt about the suitability of any proposed insulation board material or bury depth, please contact Darco. As a general rule, 2 inches of foundation grade high density extruded polystyrene foam board (pink or blue board) has an effective insulating value equal to 18 inches of natural soil cover, provided the entire excavated opening is insulated as illustrated and kept reasonably dry. Locate the insulation board a few inches above the tank, between the gravel backfill and soil cover. Slope it slightly downward toward the outer edges of the excavation as illustrated. It is not necessary to use geotextile fabric when installing insulation since the boards effectively isolate the two different backfill materials.

IMPORTANT – Standard Darco FRP tanks are designed for a maximum bury depth of 5 feet which includes the thickness of a traffic slab or any soil mound above natural grade. Consult with Darco regarding special tank designs for deeper bury applications.

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PROPER VENTING DETAILS Size vents to match or exceed the diameter of the largest external pipe feeding into or discharging from the tank system. Fiberglass tanks are designed to operate at atmospheric pressure under all conditions. Avoid potentially destructive internal vacuum or pressure conditions. Vents must be screened for insects and guarded against accidental damage or vandalism. Darco offers 4 inch, 6 inch, and 8 inch diameter standard PVC vent assemblies with plastic guards and replaceable stainless steel screens which may be ordered along with your tank. Use multiple vents where larger water discharge pipe sizes are involved.

IMPORTANT – Properly sized venting is critical when very high volume flows are anticipated, such as in fire cistern applications. Inspect vents regularly for blockage caused by vines or insect nests. Maintain the proper air space and be sure the vent outlet is above the anticipated maximum snow depth.

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MOUNDED BURIAL ABOVE SPRING LINE Under certain conditions it may be more practical to bury your tank only partially below ground and then mound soil over the tank to protect it, as illustrated. Some of these common applications are as follows: 1. The location is in an area of the country where there is no problem with frost. 2. There may be solid rock less than 10 feet below grade making a deep excavation impractical or extremely expensive. 3. Ground water may be avoided with a shallow burial close to the surface. 4. The mound of soil over the tank is an effective way to deter vehicles from driving over the site. In all such cases a bermed or mounded installation is practical and cost effective provided the following guideline is followed. In order to provide proper support, underground fiberglass tanks must be buried to "spring line" or deeper. This means the undisturbed soil around the hole must support or cradle at least the bottom half of every tank. A bury depth less than this may allow the tank to become slightly out of round or bulge at the spring line which can eventually lead to structural problems.

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I N T R O D U C T I O N IMPORTANT – FRP tanks must be totally supported, bedded, and properly backfilled to a minimum depth of spring line along both sides and both end heads. As an example; If the tank is theoretically 12 feet in diameter, it must be buried a minimum distance of 6 feet below grade - or slightly deeper if possible. Partial burial tanks should be carefully measured for deflection (out of round) both during installation and after installation when completely filled with water. Mounded tanks may be insulated with foam board if necessary and should be covered with no less than 12 inches of soil, more if possible. The soil cover will keep the sun off the tank surface and help regulate the temperature of the stored water, keeping it cool and fresh in warm climates. Cover mounds must be built up sufficiently to allow the soil to hold its normal angle of repose (approximately 1 to 1 slope or 45 degrees). Mounded sites almost always need additional soil and regular attention for the first few years until the soil settles and grass binds the sloping sides into a root mass. If grass refuses to take hold or burns out; add additional soil depth, decrease the slope angle, and water sparingly after reseeding.

IMPORTANT – Avoid placing large rocks or heavy landscape components above a tank, and discourage unnecessary use of the site as well.

COMMON TANK ACCESSORIES AS SEEN IN ILLUSTRATIONS Your tank system will require certain accessory components such as: 1. Manway extension to grade 2. Manway enclosure 3. Flanged or threaded tank fittings 4. Water level inspection hatch 5. Water level gauge 6. Float valve inlet water level control 7. Quick disconnect for manway mounted accessories 8. Inlet water filter located inside the manway 9. Overflow piping 10. High water level control device 11. Flexible couplings connecting pipelines to a tank 12. Submersible pump mounting platform at the bottom of a tank 13. Rural "Suction Dry Hydrant" or municipal “Dry Barrel Hydrant” 14. Custom made accessories

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I N T R O D U C T I O N Manway Extensions Manway Extensions allow access into an underground vessel. Generally, they are between 20 and 30 inches in diameter, and from 2 to 4 feet tall. When opening the tank is a regular occurrence (such as in an RV park sewage holding vault which may require weekly pump-outs) a 30 inch diameter manway and extension with a hinged locking cover is recommended for ease of pumping with reasonable security. In applications such as fire cisterns where access is rarely necessary, a 24 inch manway with bolted cover is adequate. In such cases a small lockable inspection hatch can be attached to the manway cover for water level monitoring. Some fire departments purposely specify a shorter manway extension such that the bolted cover can be buried slightly below the soil surface (out of sight and out of mind) in an effort to avoid vandalism and potential liability. Manways for drinking water tanks should be extended a foot or more above grade to avoid any chance of surface water infiltration.

Manway Enclosures Manway Enclosures are short lengths of large diameter fiberglass or plastic pipe that surround a manway and create a vault or working space above the tank but below the surface of the ground. In some cases the enclosure may actually be attached to the tank while in others it simply creates a wall to hold the backfill material out. Enclosures are commonly used where tank monitoring equipment or controls must be located on top of the tank but in a secure weather resistant environment. The manway diameter may be reduced to 20 inches when located inside an enclosure and should be offset to one side for maximum working room. Enclosures located under traffic slabs must be isolated or spaced away from the concrete to avoid transferring weight and vibration from the vehicles above.

Tank Fittings for Pipeline Connections Tank Fittings for Pipeline Connections up to 8 inch pipe size are standard in either an ANSI flanged or NPT female pipe threaded configuration. Larger tank fitting connections are available, but only in the flat flanged design. In certain applications it may be more practical to bond PVC or fiberglass pipe stubs into the tank and then make pipeline connections with compression mechanical joints. Contact Darco for more detailed pipeline connection information.

Inspection Hatches Inspection Hatches with padlockable 4 inch diameter caps are normally located on the manway cover. This allows a quick visible inspection of the liquid level without the lengthy process of removing the entire bolted manway cover. Inspection hatches may also be used for other functions such as refilling and taking samples.

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I N T R O D U C T I O N Water Level Gauges Water Level Gauges are available in many types from fundamental direct reading float styles to elaborate remote reading electronic devices. Darco manufactures only a simple mechanical float and dial system that directly reads the inches of water in storage, without the need for electric power. These inch by inch depth readings can be easily converted to gallons based on the size of the tank on which it is installed. Darco gauges have a weatherproof metal body with thick plastic lens through which the level indicator tape is read. Our gauge mounts on a PVC riser pipe directly above a threaded tank fitting and has a maximum water depth reading of 108 inches.

Float Valves Float Valves are water level control devices similar to the valve that maintains the correct water level in most toilet tanks. A large plastic float opens and closes a delivery valve as water is used and then is automatically refilled. These simple and trouble free devices are easy to install and require minimal maintenance. Darco offers a standard one inch size valve assembly which is flow rated at 100 GPM at 50 PSI. Larger float valves are available, but may require special design considerations.

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I N T R O D U C T I O N Quick Disconnects Quick Disconnects are used to make internal tank to pipeline connections. They can be easily disconnected to repair or clean the attached equipment. Pumps and filters are often quick connected in the manway where they can be easily removed from the surface without entering the tank. Darco offers 1 inch and 2 inch sizes in brass or polypropylene construction.

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I N T R O D U C T I O N Inlet Filters Inlet Filters are often used when incoming water contains small amounts of sand or other particles which tend to build up a layer of silt in any storage tank. Wells often carry sand along with the water which can be easily removed before storage. Darco offers an inlet filter system incorporating a universal water filter cartridge and pressure relief valve which activates only if the filter becomes completely plugged. The filter assembly attaches to the manway collar and can be quickly removed with a special T-handle tool from above. Darco sediment filters are 5 micron and are plumbed for 1 inch pipe to flow approximately 10 GPM.

IMPORTANT – Collecting water from gutters or pavement without screening and coarse filtration can load up a storage system with mud and sludge in a few short years. Removing this material and cleaning the tank is unpleasant, at best. Consider installing a simple gravity interceptor or clarifier upstream prior to storage. Contact Darco for additional information dealing with inlet water quality.

Overflow Piping Overflow Piping is often used in storage systems where the inflow of water is continuous or not controllable. When spring water is collected and piped into a storage tank, any extra water can be diverted upstream before the tank or allowed to flow through the tank system and overflow out the opposite end. Such an overflow pipe should be larger than the size of the inlet pipe for ample surge flow capacity. Always bury overflow piping below frost line and run it continuously down hill to the point of daylight discharge. The outlet should include a swing check valve and easily © 2007 DARCO, INC – ALL RIGHTS RESERVED

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I N T R O D U C T I O N cleaned discharge screen to prevent insects and rodents from traveling back up the overflow line and contaminating the cistern.

High Water Level Control A High Level Control allows any excess water in the tank to seep slowly into the backfill material surrounding the tank. A good example would be a fire cistern system where any water used is replaced soon after the fire is out. If the Fire Department tank truck dumps in too much water, the level in the tank may rise up several feet up into the manway extension, vent riser pipe, and dry hydrant draw pipe. This can lead to an ice blocked vent or a frozen fire hydrant. Installing a high level control in such a tank allows the relatively small amount of excess water to slowly trickle out into the backfill gravel. The water level then automatically drops down to a predetermined safe ice free level, maintaining the proper air space at the top of the storage tank.

IMPORTANT – Never use a high level control in a tank being filled by a well or pressure delivery water line. If the inlet valve were to malfunction, a great deal of water could be diverted directly into the tank bedding by the high level control with potentially destructive results. Pressure fed storage tank systems should incorporate a remote overflow pipe to daylight or a high water level alarm. Darco can help you with valving, water level alarm, and control issues.

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I N T R O D U C T I O N If you intend to use such a device on a potable water system, install an approved reverse flow check valve in the overflow discharge line. Darco factory high level controls include this backflow protection and should be ordered along with your tank accessory package. All tank plumbing and backflow prevention must meet prevailing plumbing codes.

Flexible Tank-to-Pipeline Couplings Flexible Tank-to-Pipeline Couplings or “flex members” are available from Darco with any tankage order in a variety of applications and pressure ratings. 1. Zero pressure (0 PSI) rain water grommets used to tie roof leaders into the manway extension, entering above the tank water level only 2. Medium pressure (25 PSI) rubber hump hoses used for septic, rain capture, and gray water gravity flow lines. 3. Medium pressure (25 PSI) convoluted stainless steel members with male pipe threads and an external vinyl jacket for tank inlet and return lines. 4. Pump pressure rated (75 PSI) single arch flanged rubber member or convoluted stainless with male pipe threads and external braid reinforcement for pump discharge lines. 5. Compression mechanical joints (75 PSI) for stub pipe connections at inlet or discharge points. Please review the following illustrations and contact Darco for assistance when selecting the appropriate flexible couplers for your project.

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I N T R O D U C T I O N IMPORTANT – Please understand that “flex couplers” are not required but are simply recommended as an accessory product to be used when and if they are requested by the Owner or his Engineer due to specific site related issues. Submersible Pump Mounting Platforms Submersible Pump Mounting Platforms are installed below the manway with sufficient tank clearance for through bolting equipment into place with stainless steel fasteners. Such platforms can be used to locate a variety of submersible equipment or piping. Standard 24” x 24” platforms are load rated at 150 pounds.

Rural Suction Dry Fire Hydrants or City Style Dry Barrel Hydrants Suction Dry Fire Hydrants or city style Dry Barrel Hydrants can be used with fiberglass fire cisterns. Our traditional suction "dry fire hydrant" used by most rural fire departments consists of a vertical 6" PVC draw pipe, 90 degree elbow, hard anodized male NST aluminum head, removable debris screen, and threaded aluminum cap. Other male NST hydrant sizes, female swivels, Storz, and cam-lock fittings are also available if requested.

IMPORTANT – As a general rule, suction piping runs to dry hydrants in 6" PVC pipe should not exceed 50 feet in total length or 15 feet of total vertical lift from the bottom of the tank for acceptable fire flows. This maximum vertical lift distance should be reduced to 13 feet or less in mountainous locations over 5000 feet above sea level. Dry Barrel Iron Hydrants are commonly installed on gravity discharge systems that require a remote hydrant which can be easily drained to avoid freezing. Iron hydrants should only be installed down hill from a cistern, such that the elevation of the bottom of the tank is above the hydrant outlet fittings. This type of low pressure free flowing discharge eliminates the need for mechanical pump priming and increases the maximum pumping discharge.

IMPORTANT – City style iron hydrants often have relatively small internal valve porting, which may reduce the suction flow rate. Order iron hydrants with the largest available internal valve for optimum flow. Contact Darco regarding these specialty products and their proper application for fire suppression water supplies designed to meet NFPA and ISO fire flow requirements.

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Custom Made Accessories Custom tank appurtenances and accessories are available through Darco based on your application or your engineering criteria. We can almost always accommodate any Architect or Engineer regarding special applications or modifications necessary to solve an unusual problem. Please contact us for help with special applications or any questions regarding underground water storage tank systems.

IMPORTANT – Check with Darco regarding those accessory components you wish to provide or fabricate yourself. We will help you with your design to ensure they meet factory approval for safety, service life, and warranty standards.

WARNING – All factory supplied internal water contact components must be suitable for potable water and should be ordered with your system. Be sure to indicate that you intend to store drinking water when you order your tank.

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I N S T A L L A T I O N DIGGING A HOLE AND GETTING THE PROJECT STARTED WARNING – 1. 2. 3. 4. 5.

Read, understand, and follow these instructions. Locate all underground and overhead utilities near the excavation site. Barricade the excavation area until the job is completed and the area is safe. Review the Installation Procedure Check List found later in this manual Review OSHA Standards and any other state or local safety guidelines which may apply to underground construction projects of this type. 6. Call Darco or your tank supplier regarding any questions you may have after "digesting" this manual (and that will take some time).

Lay out the excavation perimeter allowing 18 to 24 inches between the tank and the undisturbed excavation walls. Also allow 18 inches between multiple rows of vessels when manifolded in large volume projects. Double deadmen are required between multiple tanks, so this spacing distance must be increased to properly accommodate the width of both deadmen when anchoring is required. Calculate the hole depth considering 12 inches for bedding below the tank. Plan for all water lines and the tank bed “under drain” when such a drain can be installed. Back slope or bench the excavation walls to provide a safe working environment. Properly bed the entire floor of the hole with 12 inches of approved backfill gravel and rake it level where the tank and deadmen will be positioned.

IMPORTANT – Review the tank system layout and have all the correct tank accessory components ready to go. If your system has bottom discharge piping, preassemble the isolation valve and flex assembly before placing the tank into the hole. Level each vessel in two directions using a laser or spirit level placed across the manway opening flange. Shovel and probe at least 12 inches of gravel under the center on both sides of the tank. If deadmen are to be used, lower them into place and strap down at this time. For purposes of this manual, we will primarily deal with deadman anchors rather than slab anchors since deadmen are far more commonly used. OPTIONAL WATER BALLAST FOR TANK STABILITY When water is available at the site, adding ballast is recommended to help hold any vessel in the proper location while backfill is applied. Backfill material may jar or rock an unanchored tank if carelessly dumped against the tank. Such disturbance or rocking movement tends to allow the backfill to migrate under the tank ribs and raise it slightly upward and out of level. 10% water ballast adds significant weight and substantially increases tank stability. This water weight allows you to probe aggressively and work more freely with the backfill material. There is no need to add additional water beyond the 10% until the backfill process is complete to grade.

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I N S T A L L A T I O N IMPORTANT – Wait until the tank is entirely buried and supported by backfill before filling the tank completely. The water level inside any tank should never be allowed to rise higher than the surrounding gravel supporting it on the outside.

IMPORTANT – It is perfectly acceptable to install Darco tanks without water ballast, but you must take extra care not to disturb or rock the tank while loading gravel into the hole by machine. Fill the tank as soon as possible once the backfill work is completed to grade.

BACKFILL PROCEDURE Backfill must be applied in lifts no greater than 12 inches deep at any time to allow proper hand shoveling and probing of the material between all ribs and under the tank's belly and haunches. Work evenly around the tank, shoveling and probing until gravel fills all the voids and even resistance is felt as the probe is plunged in below the tank. Probing is time consuming and physically taxing, especially if the system is large. However, there is no other way to do this job properly and create the uniform balanced support required to cradle the many tons of water involved. Hand probe any underground tank relative to the face of a clock, in multiple lifts from the 4:00 position around underneath to the 8:00 position.

IMPORTANT – On tanks equipped with sump projecting downward beyond the belly of the tank, be sure the sump is well supported with probed gravel. Excavate a pocket in the bottom of the bed to receive the sump. Allow sufficient room to backfill the pocket with gravel and probe it with a short tool. This is a difficult process and requires the installer to lie on his stomach while working below the haunches of the tank.

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TANK DEFLECTION MEASUREMENTS Deflection is a term that describes a tank that has changed shape or that is distorted and no longer round. Some limited deflection is acceptable and Darco fiberglass tanks will tolerate minor deflection when comparatively measured before and after installation as illustrated below. Deflection is an excellent indicator as to the care taken and quality of the tank installation work. The measured total deflection at the center of the tank should be less than 2%, either larger or smaller than the original internal diameter measurement, when completely backfilled to grade. Check for deflection three or four times during the backfill process to make sure the job is progressing properly, without excessive deflection. As the Owner, you will want to carefully watch over your installing contractor with regard to proper backfill probing technique, periodic deflection measurements, and machinery approach distances.

IMPORTANT – Excessive deflection is generally caused by 3 common errors. 1. Overly aggressive backfill application - too much and too fast (in a hurry). 2. Unbalanced backfill application - not working evenly around the entire tank. 3. Driving heavy machinery too near or even over the tank system – keep machinery wheels or tracks 10 feet away from the tank perimeter.

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I N S T A L L A T I O N HYDROSTATIC LEAK TESTING Leak testing can only be done safely in the field by filling the tank with water and waiting to see if the level drops over a period of time. The tank must be backfilled for proper support before water is added beyond the 10% desirable for initial ballasting. Once the backfill gravel has reached the top of the tank and is at the natural angle of repose on all 4 sides, then and only then can the tank be completely filled. Plug the top mounted fittings and install the manway extension with gasket. Slowly fill the tank until the water is up even with the manway flange gasket, at the joint between the flanged tank collar and the extension. Observe the water level over a 24 hour period. Replace the cover securely overnight for safety. It may be necessary to add a small amount of water as the liquid temperature stabilizes to match the temperature of the soil. Trapped air at the top of the tank can also cause minor variations. Generally, the water will maintain a stable level at the gasket surface with less than ¼ inch variation. In the unlikely event that you are experiencing a drop in water level after several additions, call Darco for help in determining how to best proceed from this point.

GEOTEXTILE FILTER FABRIC Geotextile or “filter fabric” is recommended as a barrier or separator medium between the backfill gravel and the soil cover. Geotextile material is inexpensive, readily available, and keeps the cover soil from migrating down into the porous rock interface. This helps reduce subsidence of the cover mound over time and increases the frost resistance of the site in general by keeping the insulating air spaces open between individual gravel particles. It is not necessary to use filter fabric over the areas covered with foam board insulation since the insulation also effectively stops this downward soil migration. © 2007 DARCO, INC – ALL RIGHTS RESERVED

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FINAL SITE DETAILS Provide surface water a natural run off path, away from the tank site. Seed grass to prevent erosion and padlock or bolt the manway cover closed to discourage curious children. All PVC pipe & fittings exposed to sunlight should be painted to reduce long term ultraviolet degradation (unpainted PVC gets brittle with time).

IMPORTANT – Never leave newly installed tanks empty. Always fill the tank system completely and secure the manway cover before leaving the site.

PVC PIPING Schedule 40 PVC piping with solvent cemented joints is recommended for all pipeline applications up through 6 inch standard pipe size. 8 inch PVC is difficult to assemble for inexperienced installers and will require extra manpower as well as large dobbers for primer and slow setting cement. Large PVC pipe will need to be seated with a wooden block and light tap from a mall to drive each joint fully tight. We discourage using rubber gasketed slip fit PVC pipe in fire cistern suction lines since pump vacuum can cause air leakage at the uncemented joints. However, rubber gasketed SDR35 PVC pipe is recommended for rainwater collection lines and manifolds since there is a wide variety of accessory fittings and saddles available which makes piping in complex runs much easier to assemble.

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I N S T A L L A T I O N UNRESTRAINED MECHANICAL COMPRESSION JOINTS (MJs) Ductile Iron and C900 plastic piping can be easily connected directly to fiberglass cisterns when a stub PVC pipe is installed in the tank instead of a threaded or flanged fitting. Care must be taken to install the correct transition ring gasket based on the actual stub pipe outside diameter. Numerous different ring gaskets are available so you must be sure to have the correctly sized seal for the pipe outside diameter you intend to grip. If you need additional information, contact Darco or your pipe supplier when using mechanical compression type joints. An additional benefit from MJs is the fact that they employ a flexible ring seal which will help offset minor pipe misalignment and minor shifting of the pipe or tank during backfill. We recommend such mechanical connections only when pipe diameters are above 6 inch, and joint restraint is unnecessary.

POTABLE WATER OR "DRINKING WATER" TANK ISSUES Darco FRP tanks are designed to store potable water and are manufactured from FDA (Food & Drug Administration) accepted raw materials. When NSF (National Sanitation Foundation) compliance is required, the special liner resin used must be recognized and listed by the NSF. When required, Darco will provide a letter to the Owner or Engineer explaining the process and identifying the resin actually in contact with the water.

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I N S T A L L A T I O N WARNING – Use only new, clean, tanks that are manufactured from FDA compliant materials and properly designed for storage of drinking water. Never attempt to clean up any used vessel for potable water applications. Locate the inlet and outlet plumbing such that fresh water continually flows throughout the entire length of the system without creating trapped or stagnant areas. As a general rule, store unchlorinated potable water no longer than 30 days and size your system based on a reasonable water exchange rate. Upon completion of the tank installation and piping system, flush the tank and pipelines with clean potable water. Follow your local city or county regulations for the "start-up" of a potable water storage system. These regulations vary from state to state but generally include the addition of a disinfectant such as chlorine and subsequent flushing. Take the required water samples before using your system. Additional periodic samples are recommended particularly when a shallow well is the water source. Such samples are inexpensive and good insurance against the ingestion of pollution and pathogens. Take extra precautions to see that the tank and piping remain covered and as clean as possible during the installation process. Use plywood over the manway openings and duct tape all smaller fitting holes during backfill. Climb inside as little as possible to do fitting or assembly work, and keep your boots clean.

IMPORTANT – Most drinking water storage tanks filled from wells or springs will develop a dark silty layer of fine sand particles in the bottom of the tank over time. This is normal and may have to be cleaned out or flushed every few years. Silt build up several inches deep can harbor bacteria. Filtering water thoroughly before it is directed into the storage tank will help eliminate such silt build up. Be prepared to change water inlet filter cartridges as frequently as every month if necessary, especially when a newly drilled well is first put into production. You should inspect your tank and test the tap water on an annual basis. Darco offers a well water inlet filter assembly which is mounted inside the manway and can be serviced remotely from the surface, without entering the tank.

FIRE CISTERN ISSUES Fire cisterns are becoming increasingly popular as large expensive homes proliferate in the forested regions around large cities like Los Angeles and Denver. With limited reliable year-round water supplies in these remote areas, many fire departments are forced to abandon expensive structures in the face of wildfire. Individual citizens and homeowner associations often install water storage tanks in a working relationship with their local fire departments. When water is available; lives may be saved, property can be protected, and fire insurance premiums often drop. It is extremely important that any effort along these lines be coordinated with your local fire department or the appropriate local governmental agency.

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I N S T A L L A T I O N IMPORTANT – An improperly sized or improperly located fire cistern may be of little use, despite the homeowner's good intentions. Check with your Fire Chief before starting on an emergency fire protection water storage system. Fire cisterns for individual family homes or ranches are generally sized from 4,000 to 10,000 gallons. Cisterns for an entire neighborhood or small subdivision can be as large as 50,000 gallons or more. Generally this water is not located in one spot, but rather in multiple smaller tanks at strategic "all weather" accessible locations near clusters of homes or along main access roads. Developers are often required to install fire cisterns in rural subdivisions where the only water sources are low volume single family wells. Local regulations and fire fighting strategies vary from state to state and county to county. Not all fire departments have the same water storage requirements. Some residential insurance companies give credit for a rural fire fighting water supply, yet others don't. It is your responsibility to research these issues in your area and to comply with the local “Authority Having Jurisdiction” - make no assumptions. Collect information from multiple sources if possible and prepare for minor confusion. Darco tanks can be sized to meet the storage requirements and flow rates formulated by the NFPA (National Fire Protection Association). Working through these water supply issues can be time consuming and very frustrating. Please study the enclosed illustrations of our standard fire cisterns and feel free to call if you are having difficulties understanding the most practical application for such systems. Often it is expeditious to set up a 3-way conference call between the Owner or Developer, the Fire Marshal, and the Tank Manufacturer. This gets all the responsible parties on the same page, from the start.

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I N S T A L L A T I O N SEPTIC TANK ISSUES A Darco fiberglass tank can be baffled and configured to make an excellent multi-stage septic tank for any large commercial or industrial wastewater application. RV camp sites, race tracks, and state parks are common users of large "on site" wastewater treatment or holding tanks. Applications such as these must be designed by an engineer and approved by the local Department of Public Health.

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I N S T A L L A T I O N SAFETY ISSUES It is the responsibility of the Owner and his Contractor to understand and follow established safety guidelines with regard to general excavation practices and confined space operations involved with installing underground water tanks.

WARNING – It is the responsibility of the owner or his contractor to locate all overhead and underground utilities before operating cranes or excavating equipment.

WARNING – Excavation for the burial of tanks and piping can lead to trench wall collapse and serious injury or death. Follow OSHA 1926 - 65 / P Trench Safety Guidelines. WARNING – A new - dry - unused tank is a confined space but is safe to enter "without permit" if the space is properly ventilated. Remove all manhole covers and fitting plugs for at least 30 minutes of natural ventilation before entering a new fiberglass tank to install internal components. Always have a co-worker standing by outside to assist the worker inside. NEVER WORK ALONE. Tanks that are currently in service or have been previously used, may hold noxious fumes, flammable gasses, or may not contain enough oxygen for breathing. Whatever the case, if the tank is not new and dry, you should take the following minimum precautionary steps prior to entering: 1. Determine what was being stored in the tank. 2. Monitor for combustible gases. 3. Force ventilate using a powerful motor driven fan with a “trunk hose”. 4. Confirm that the internal oxygen level is adequate. 5. Beware of the pathogenic danger around sewage holding tanks. 6. Review the applicable OSHA Confined Space Entry Guidelines.

WARNING – Never use plastic pipe primer & cement, cleaning solvents, paints, sealers, or similar volatile or noxious materials when working inside any poorly ventilated storage tank. Fumes from the pipe cement or solvents can lead to unconsciousness and death from asphyxiation. Pipe connections which must be made while working inside any tank should be threaded, bolted, clamped, or other mechanically sealed design. NEVER WORK ALONE.

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CONTRACTOR'S QUICK CHECK INSTALLATION PROCEDURE This step-by-step overview of the installation process is a general guideline for planning purposes only. Each installation is different and may require a slightly modified procedure based on the variables of that particular project. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36.

Locate property lines, easements, overhead and underground utilities Assess the job site for adequate bearing (PSF), presence of ground water, evidence of expansive clay or seismic activity, and other detrimental factors Pull permits and get proper district or agency approval (Fire or Health Dept.) Plan for tank arrival & transfer from delivery truck to your trailer (if necessary) Form and pour concrete deadman anchors at least 1 week in advance Order galvanized anchor cable and clamps if not provided with tank Schedule a water delivery truck for initial ballast water and final fill-up later Order approved gravel backfill material meeting the Darco sieve analysis Plan for barricade fencing materials around the open hole Lay out the tank excavation perimeter with "upside-down" paint Lay out piping runs and subdrain to daylight with "upside-down" paint Check to see that you have all system accessories & hardware on site Excavate and backslope or bench the tank hole and piping trenches Use excavated soil to form a low berm around the hole to divert rain water When conditions require, construct a concrete slab anchor in bottom of hole Install perforated, fabric covered bed drain piping, if appropriate for the site Bed the bottom with 12 inches of approved backfill aggregate and rake level Lay out multiple tank locations on the gravel bed with "upside-down" paint Have extension ladders and lifting equipment ready to meet the delivery truck Rig each tank properly and lift it from the trailer and into the prepared hole Install deadman anchors on top of bedding in the proper locations Temporarily cover each manway and fitting opening to keep the tank clean Position and level the tank by instrument or spirit level in two directions Load a small amount of backfill into the hole around the outer perimeter (Try to avoid bouncing gravel off the tank or disturbing it in any way) Carefully shovel & probe backfill below the center 2 feet from both sides Connect any bottom discharge piping after tank is stabilized and level Add 10% water ballast if water if available; Darco tanks can be buried dry Wait 30 minutes to inspect for leaks at all submerged pipeline connections Install and tension anchor cables from straps to the anchor system (if used) Make & record your baseline deflection measurement through the manway (On tanks without a manway, use a centered vent or accessory fitting) Proceed with backfill in 12 inch lifts working uniformly around the tank Probe each gravel lift under the belly of the tank and carefully around fittings Make periodic deflection measurements as backfill work progresses upward Perform hydrostatic leak testing if required by the owner or jurisdiction Install the manway extension and top mounted accessory risers & pipelines If a traffic slab will be poured above, continue gravel fill to bottom of slab

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I N S T A L L A T I O N 37. Once gravel covers the tank several inches deep, rake smooth and apply geotextile fabric or 2 inch polystyrene rigid insulation board 38. Pour reinforced 8 inch concrete traffic slab above tank area when required 39. Make a deflection measurement (log all such measurements in your manual) 40. Keep heavy machinery a safe distance from the tank during final cover work 41. Mound soil to the proper total cover depth and dispose of excess material 42. Make another deflection measurement and record it in your manual 43. Finish grade, divert and ditch water away from site to avoid pooling or erosion 44. Fill the tank immediately upon completion of the basic installation work 45. Install all top mounted accessories such as a fire hydrant and vent head 46. Make final deflection reading in wet tank and compare with previous figures 47. Follow disinfection & water testing procedures per your local Health Dept. 48. Bolt or padlock the manway cover to discourage children and vandals 49. Install a fence or suitable barricade to keep vehicles well away from the site 50. Seed the entire disturbed area with grass to reduce erosion 51. Paint exposed PVC pipe risers for long term protection against sunlight 52. Install proper signage or post warnings (if required) 53. Call for final inspection and notify the appropriate permitting agency or district 54. Routinely inspect surface mounted accessories, vents, manways, overflows, etc. 55. Sample for water quality at least annually in all potable water systems 56. Change well water inlet filter cartridges regularly for pump efficiency 57. Check the soil cover in 12 months and reshape or restore any sunken areas ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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WARRANTY DETAILS Please review the following limited 2 year structural and corrosion warranty as applied to all approved water tank installations. Contact Darco if you have any questions regarding interpretation of this very specific document as illustrated.

IMPORTANT – This warranty applies only to the vessel and primary accessories manufactured or assembled by Darco Inc. Unmodified secondary accessories sold in conjunction with Darco products (such as a submersible water pump manufactured and packaged by others) will be warranted through Darco, but only to the limits established by the original manufacturer. An extended warranty is available for water storage systems only. All other applications are restricted to our basic 2 year warranty duration as registered and confirmed from the date of possession. The extended warranty coverage for water tanks is available for an unlimited number of additional years, based on the following flat rate formula: Beginning with the 3rd year through 10 years: 2% of the sale price of the wet tank package (excluding external accessories and freight) times the extension period requested by the original purchaser in whole years. The extended warranty coverage is identical to the basic 2 year warranty program provided with every Darco water storage system sold. From 11th year on: 1% times the extension period requested in whole years.

Make no assumptions – read the warranty coverage CAREFULLY.

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UNDERGROUND WATER STORAGE TANK WARRANTY THE WARRANTOR: Darco Incorporated P.O. Box 779 Bennett, Colorado 80102 Phone: 800-232-8660 DURATION: Darco warrants that its tankage products will not leak, corrode, or structurally fail due to inappropriate design, improper use of materials, defects in materials, or poor manufacturing workmanship, for a period of 2 years from the date of original purchase. Unlimited additional years of extended coverage may be purchased directly from Darco, but only at the time of the original sale. This extended warranty applies only to tanks used for water storage. RESTRICTIONS: The following structural and corrosion warranty applies only to new fiberglass underground water storage tank systems and accessories manufactured by Darco Incorporated as sold to the original owner. The application and installation must follow our published installation manual as supplied with every vessel when sold. EXCLUSIONS: The following is a nonexclusive list of typical claims that will be barred or disallowed by this limited warranty (problems with or damage related to): improper installation, commercial shipment, abuse, vandalism, destructive acts of nature, storage of unapproved materials, ice in tank or piping, settling or other tank movement, tank buoyancy, use in unapproved locations, internal vacuum or pressure conditions, secondary accessories supplied by others, storage of hot water (over 150o F.), or unapproved structural tank modifications. RESPONSIBILITIES: The warrantor's total financial liability shall not exceed the purchase price of the products sold f.o.b. point of factory delivery or initial sale. It will be the option of the warrantor to repair, replace, allow credit, or refund the original purchase price in remedy of any claim. Said product shall not be considered defective if it substantially fulfills all performance requirements. Reasonable time must be allowed for the warrantor to review any claim and make remedies. Repairs may only be made by an authorized representative of the warrantor. All initial costs anticipated during the investigation of any warranty claim are due in advance and shall be the responsibility of the owner until such time as the cause of the claim is identified and the responsible party determined. Darco will not be liable for any incidental or consequential damages, materials lost, property damage, or injury caused by any defect in any product or accessory sold. Darco shall have no responsibility for tank removal or re-installation costs related to the replacement of warranted vessels. Nor shall the warrantor be liable for unspecified or additional materials, labor, or transportation involved in the resolution of any claim. The foregoing warranty constitutes Darco's exclusive obligation and Darco makes no other warranty or representation, expressed or implied, with respect to it's products or any related service, advice, or consultation furnished to any purchaser by Darco or it's distributors and dealers. Claims must be received in written form before the end of the coverage period and must be supported with an original bill of sale and positive owner identification. VERIFICATION: Save your original bill of sale, extended warranty documentation, and shipping information as it will be required to validate and process any warranty claim when filed.

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I N S T A L L A T I O N TANK PURCHASE GUIDE SPECIFICATION UNDERGROUND FIBERGLASS TANKS Please review the following “Darco Underground Water Tank Specifications”. In an effort get a meaningful comparison between tank manufacturers, we suggest that you as the purchaser compare both our warranty and structural specifications against other fiberglass suppliers and other water storage products. We are confident that Darco will not only give you the best price per gallon, but also a cost effective structural vessel design for your specific application, a comprehensive tank accessory package, and prompt on-time personalized delivery.

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I N S T A L L A T I O N SPECIFICATIONS FOR FIBERGLASS UNDERGROUND WATER STORAGE TANKS PREFERRED SUPPLIER: Darco Incorporated - 980 Darco Drive - Bennett, CO 80102 Phone number 800-232-8660, Fax 303-644-5001, Internet - www.darcoinc.com GUIDING DESIGN PUBLICATIONS ANSI / AWWA D-120 - Self certified vessels for underground direct bury domestic potable water service. ANSI / AWWA M-45 – Fiberglass pipe design / those design parameters applicable to underground water tanks. ASTM D3299 / 95 - Those sections pertaining to materials, general construction techniques, and workmanship / as applicable to underground direct bury water storage tanks. ASTM D4021 / 92 - Those sections pertaining to design and testing of underground direct bury water storage tanks / 6.4.1 Earth Loading and 6.4.3.2 Hydrostatic Testing.

ENGINEERING APPROVAL When requested, complete structural tank family design calculations, sealed by a Registered Professional Engineer, must be made available.

DESIGN BASIS FOR STANDARD TANKS 1. External Hydrostatic Pressure: In empty condition, anchored, backfilled, and totally submerged below 5 feet of water flooded gravel to grade; the tank shall provide a design factor of 2 to 1 against buckling. 2. Internal Loading: When fitted with a Darco testing manifold, the tank must withstand a 3 psi air pressure test; or when properly backfilled to spring line, an air over water net 10 psi hydrostatic pressure test; with a design factor of 2 to 1 against rupture. 3. Traffic Loading: When installed according to the Darco Instructions, incorporating an approved concrete traffic slab on grade, the tank must withstand H-20 continuous daily vehicle axle loads (32,000 pounds per axle). 4. Specific Gravity: Design is for potable water or domestic sewage at 1.2 specific gravity. 5 Temperature: Design is for a maximum hot water impingement temperature of 150 degrees Fahrenheit. 6. Venting: Design is for internal atmospheric pressure, including both fill and discharge cycles. 7. Bury Depth: Design is for a standard soil cover depth up to 5 feet maximum, with deeper bury designs available upon request.

FACTORY TESTING All tanks shall be proof tested for buckling resistance to 10 inches of mercury vacuum and also low air pressure tested under a soapy water spray for pinhole leak detection.

INTERNAL FINISH AND FIT All internal seams and fitting penetrations shall be overlayed and smooth leaving no crevices, exposed edges, or protruding fibers.

GLASS FIBER TO RESIN RATIO The structural glass fiber content shall be 35% minimum with no addition of sand fillers.

POTABLE WATER STANDARDS The tank’s internal water contact resin layer shall meet FDA standards and be listed under ANSI-NSF 61 as suitable for culinary or domestic drinking water contact.

TANK FITTINGS Standard fittings shall be of compatible fiberglass construction with a flat faced flange or female tapered pipe thread design. Fittings over 3 inch diameter shall withstand 300 foot pounds of torque if threaded or a moment load of 2000 foot pounds if flanged. Pipe stub-outs in PVC or fiberglass must also be available.

LIFTING LUGS The combined capacity of designated lifting lugs shall be 2 times the empty tank weight.

CAPACITY AND SIZE REQUIREMENTS 1. The nominal volume of the tank shall be _________ gallons. 2. The nominal tank diameter shall be _________ feet by a nominal length of _________ feet.

LIMITED WARRANTY A standard 2 year structural and corrosion warranty shall become effective upon the tank delivery. An OPTIONAL EXTENDED WARRANTY PROGRAM shall be made available only at the time of the original tank purchase.

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I N S T A L L A T I O N CUSTOMER COMMENTS AND INSTALLATION EXPERIENCES Enrique Silva - New Mexico "Have plenty of help and several long ropes when unloading or moving large tanks on windy days. We had a tank 54 foot long tank swing out of control and hit a boulder. The damage wasn't too bad and it was easily repaired. I was a man short that day and trying to beat an incoming snow storm". Jim Jackson - Colorado "I made a pair of 10 foot long very heavy I-beam "stingers" for the corners of our big loader bucket before your tank arrived. It worked well and gave me the extra lifting height to easily unload the delivery trailer and place the tank without getting too close to the edge of the hole. With that extension the loader was almost at the balance point, so any larger tank would have been a big problem. In the future, I am going to allow for a crane in my installation quote”. Carl Weiss - Utah "Using a spreader beam made lifting our two 40,000 gallon tanks off the trucks and directly into the hole a piece of cake. It cost me an extra $80 to have the crane company trailer their big spreader out to my job site, but it was worth it. The whole thing was over in less than two hours, done safely and efficiently". John Graff - Upstate New York "We had a very tight driveway with sharp turns to negotiate with your delivery tractor / trailer. The driver was uncomfortable about the curves and was not sure he could turn around at the other end. We avoided possible problems by transferring our tank from the delivery trailer to our shorter machinery trailer which we knew would make it up to the site and be able to get turned around. I padded the rough deck with a bunch of old tires, strapped it down, and up we went”. Andy McDonald - Tennessee "It had been raining for several days before our tank was scheduled to be delivered. There was going to be no way to get your semi near the hole we had prepared. The tank would have to be trammed in from the paved road with our track hoe. I talked with the people at Darco about this process and they suggested using soft woven slings rather than rigid cable chokers. The nylon slings we used had some give to them and didn't shock the tank or the lift lugs as we lurched along the rough muddy road to the site". Phillip Malland - Texas "Our well had not been drilled yet so we had to bury the tanks dry, without the recommended 10% water ballast for stabilization. We were very careful with the backfill at the start. Once the tanks were sort of locked into place at the ends, I put as much pea gravel as I could on top of the tanks, and it seemed to help. Maybe 1000 pounds of gravel stayed up there along the centerline. I would have used a little water for ballast if I had any. The only down side was that we were continuously peppered with gravel from above as we probed along the tank sides”.

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Please let me know how you like our products and feel free to make a suggestion or criticism. I paraphrase some of these discussions into our "Customer Comment" section and try to update it from time to time. John Small / 800-232-8660. I really enjoy the feedback - good or not so good. Thanks

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I N S T A L L A T I O N D R A W I N G S The following is a collection of illustrations, concepts, and installation diagrams. Hopefully some of what you see here will help you with your tank selection or planned installation. If reviewing these pages creates questions for you, please contact Darco toll free at 1-800-232-8660. THANK YOU FOR TAKING THE TIME TO WORK THROUGH THIS MANUAL. List of Drawings Fiberglass Tank Product Line Part 1 ............................................................................................................ 60 Fiberglass Tank Product Line Part 2 ............................................................................................................ 61 Flex Couplers 1 ............................................................................................................................................. 62 Flex Couplers 2 ............................................................................................................................................. 63 Overflows ...................................................................................................................................................... 64 Float Valve High Level Control ..................................................................................................................... 65 Inlet Filter For Well Water ............................................................................................................................. 66 Fire Cistern Concepts #1 .............................................................................................................................. 67 Fire Cistern Concepts #2 .............................................................................................................................. 68 Fire Cistern Concepts #3 .............................................................................................................................. 69 Fire Cistern Concepts (Suction) ................................................................................................................... 70 Fire Sprinkler Reservoir ................................................................................................................................ 71 Fire Apparatus Pump Test Station ............................................................................................................... 72 Manway Information 1 .................................................................................................................................. 73 Manway Information 2 .................................................................................................................................. 74 Manway Information 3 .................................................................................................................................. 75 Manway Information 4 .................................................................................................................................. 76 Submersible Pump With Float Controls........................................................................................................ 77 Float Switch Tree in Manway........................................................................................................................ 78 Jet Pump in Manway Vault ........................................................................................................................... 79 Potable Water Treatment & Delivery System ............................................................................................... 80 Wet Well Delivery System ............................................................................................................................ 81 Insulated Underground Tanks ...................................................................................................................... 82 H-20 Traffic Slab Details ............................................................................................................................... 83 Crested Butte Installation Photos ................................................................................................................. 84

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Figure 1 Fiberglass Tank Product Line Part 1

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Figure 2 Fiberglass Tank Product Line Part 2

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Figure 3 Flex Couplers 1

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Figure 4 Flex Couplers 2

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Figure 5 Overflows

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Figure 6 Float Valve High Level Control

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Figure 7 Inlet Filter For Well Water

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Figure 8 Fire Cistern Concepts #1

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Figure 9 Fire Cistern Concepts #2

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Figure 10 Fire Cistern Concepts #3

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Figure 11 Fire Cistern Concepts (Suction)

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Figure 12 Fire Sprinkler Reservoir

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Figure 13 Fire Apparatus Pump Test Station

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Figure 14 Manway Information 1

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Figure 15 Manway Information 2

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Figure 16 Manway Information 3

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Figure 17 Manway Information 4

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Figure 18 Submersible Pump With Float Controls

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Figure 19 Float Switch Tree in Manway

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Figure 20 Jet Pump in Manway Vault

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Figure 21 Potable Water Treatment & Delivery System

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Figure 22 Wet Well Delivery System

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Figure 23 Insulated Underground Tanks

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Figure 24 H-20 Traffic Slab Details

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Figure 25 Crested Butte Installation Photos

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