SPECIFICATIONS FOR POLYETHYLENE UNDERGROUND WATER TANKS
Preferred Manufacturer: Darco Inc. 980 Darco Dr. - P.O. Box 779 - Bennett, CO 80102
Phone number 800-232-8660, Fax 303-644-5001, Internet - www.darcoinc.com
GENERAL GOVERNING STANDARDS
1. ASTM 1998-93, Polyethylene Storage Tanks, those specific sections considered germane and prudent as applied to underground water storage tanks only.
- Section 4 : Type 2 high density virgin linear polyethylene resin
- Section 5 : Material standards for food contact grade polyethylene resin
- Section 7 : Fittings for polyethylene water tanks
- Section 8 : Performance requirements based on impact testing
- Section 9 : Dimensions and tolerances
- Section 10 : Workmanship
DESIGN STANDARDS / DARCO MODULAR POLYETHYLENE OCTANK SYSTEMS
1. External Hydrostatic Loading : The empty tank system with manway risers, when anchored into a sand backfilled excavation at a 3 foot bury depth and flooded with water to spring line, must maintain its structural shape and 100% water tightness.
2. Traffic Loading : Tank systems, when properly installed and incorporating an approved concrete surface slab, must withstand automotive and H20 truck traffic loads.
3. Dry Bury Installation : Tank systems must have sufficient wall strength and structural integrity to be installed and completely backfilled to a 3 foot bury depth without the addition of water during the backfill process. Furthermore, tank systems must maintain their structural shape and full storage capacity when left empty for extended periods.
All fittings shall be of polyolefin or PVC construction and incorporate only 300 series stainless steel hardware. Compatible and warranted tank-to-pipe flexible couplers must be made available along with the tank system at the time of purchase. Fittings, gaskets, and hardware must be available specifically for domestic water use.
POTABLE WATER APPLICATIONS
The virgin polyethylene resin used for construction of potable water storage tanks must be NSF listed and comply with FDA Title 21 when in contact with drinking water.
The accessory package provided with any storage tank system must contain only fully approved accessories and appurtenances which meet all performance standards and warranty coverage guidelines of tank manufacturer.
CAPACITY AND SIZE REQUIREMENTS
1. The nominal volume of the tank system shall be ______ gallons.
2. The nominal tank diameter shall be ______ feet by a nominal length of ______ feet.
A standard 2 year structural and corrosion warranty shall become effective upon tank delivery. An optional extended warranty program must be available at time of purchase.
As a RESELLER of Darco Underground Water Storage Tanks, I understand that I have the responsibility to relay critical application and installation information to the Owner and Installer of any storage system. I am prepared to explain the guidelines by which Darco Tanks may be properly installed and used. I realize that Darco can provide either Polyethylene or Fiberglass vessels and that their applications and installation procedures are not identical. I will contact Darco about customer questions I may be unable to answer regarding such information.
- Darco Tanks are suitable only for water and water based domestic sewage.
- Backfill and tank cover material required for Polyethylene tanks is clean sand.
- Backfill and tank cover material required for Fiberglass tanks is pea gravel.
- Bury depth is limited to 3 feet for poly tanks and 5 feet for fiberglass tanks.
- Tanks to be used for potable water must be ordered for that specific use.
- If high ground water is possible, anti-flotation measures must be taken.
- A traffic slab is required whenever surface vehicular loads are anticipated.
- Fire cistern design and location must be approved in advance by the Fire Dept.
- Darco wastewater treatment applications must be pre-engineered, stamped, and approved
- Under certain conditions, it may not be legal to capture and store rainwater.
- Hot water from any source is not permitted in Darco polyethylene tanks.
- Installation must follow published Darco guidelines and site requirements.
- A signed approval drawing is required prior to acceptance of any tankage order.
- The appropriate installation manual will be mailed in advance to every customer
- This document must be signed and returned to Darco prior to order acceptance.
- Sales within the State of Colorado will require a copy of your sales tax license
- Any sales tax license must be current and the name must match our invoice.
- Sales outside Colorado will require the reseller to acknowledge all tax liability.
- I am aware that all NET 30 accounts are due in full 30 days from the ship date.
- I understand that late accounts will incur an interest charge of 1.5% per month.
- Darco reserves to right to deny credit or withdraw existing credit at any time.
SPECIAL FREIGHT GUIDELINES:
Wide Load freight quotations are best estimates and subject to demurrage and other additional charges based the actual mileage traveled as affected by weather, highway detours, and other factors beyond our control. Delivery dates and times are approximate and subject to the minor revisions and adjustments.
Project Name or Identification ________________________________________
Business Name of Reseller __________________________________________
Signature of Reseller _______________________ Title ___________ Date ____
Final Warranty Holder ________________________________
REVISION DATE 12-06