TABLE OF CONTENTS

A. THE BACKGROUND

B. ENGINEERED FOR SAFETY

C. THE MANUFACTURING PROCESS

1. The Steel Tank Construction
2. Secondary Containment
3. Concrete Vault
4. Coating and Finishing

D. ADDITIONAL FEATURES

1. Complying with Environmental and Fire Safety Requirements
2. UL/ULC Listed
3. Overfill Protection
4. Venting
5. Support Legs
6. Thermal and Corrosion Protection
7. Spill Containment
8. Vehicle Impact Resistance Bullet Resistance

E. TANK WEIGHTS AND DIMENSIONS

F. PERMITS AND APPROVALS

A. The Background

1. You are probably aware that underground fuel storage tanks are a main source of soil contamination in this country. Underground fuel storage tanks corrode and leak fuel oil and gas into the soil and cause soil contamination. The contamination may even reach the underground water streams and be carried into the drinking water systems. Decontamination of the underground fuel storage tanks’ location is extremely costly and can have a devastating financial burden on tanks’ owners and operators.
   
2. Regulatory agencies have enacted many guidelines requiring the owners and operators of the underground fuel storage tanks to install expensive leak detection and monitoring facilities to prevent costly contamination problems.
3. There are also many regulations covering installation and operation of "unprotected" above ground steel storage tanks.
4. To solve the problems associated with the underground storage tanks and the unprotected aboveground steel storage tanks, ConVault® has come up with a breakthrough idea of constructing a tank that does not have the costly underground tank’s leak monitoring system and contamination problem and at the same time has overcome the problems associated with the unprotected aboveground steel tanks. Because of its unique monolithic concrete construction feature, the ConVault® tank system provides a two (2) hour fire protection, vehicle impact resistance and bullets resistance proven by the tests carried out by the Underwriters Laboratories of USA (UL) and Canada (ULC).

B. Engineered for safety

1. The design and manufacturing concept of the ConVault® is simple and at the same time very practical. In a nut-shell, ConVault’s® design concept consists of :

   a. Constructing a welded steel tank to hold and store flammable and combustible liquid fuels.

   b. Insulating the steel tank exterior by a minimum of 1/4" thick Styrofoam and wrapping it in a 30 mil high density polyethylene membrane to provide a secondary containment for fuel in case of a remote probability of any leaks from the steel tank.

   c. Encasing both the poly and the steel tank in 6" thick monolithic reinforced concrete vault to provide two-hour fire protection, ballistic and vehicle impact protection.

2. ConVault® has even designed a leak detection system that enables checking the tank for leaks on a regular basis by simply inserting a stick in the leak detector chamber and find out if the tank has any leaks.
3. ConVault® is so confident of its superior design that it gives 20 to 30 years of warranty for its tanks. Provided that the tank is installed, operated and maintained in accordance with ConVault’s® specifications, ConVault® will replace your tank without charge if it develops a leak. See your standard warranty for its actual number of years and its conditions.
4. Since you have purchased one of over 18,000 tanks, which remain in service since 1987, you may wish to understand the unique manufacturing process of Convault tanks. The following paragraphs will explain the construction process of the ConVault® tanks.

C. The Manufacturing Process

ConVault® tanks construction process consists of four main steps, namely:

1. Steel tank construction
2. Secondary containment
3. Concrete Vault
4 .Coating and Finishing

Figure No. 1 is an isometric view of a typical ConVault® tank with a cutaway section to show details of a ConVault® tank system.

1. Steel tank construction

a. ConVault® steel tanks are made of 1/8" or 3/16" thick steel, depending on warranty and tank size. The steel tank contains and holds the liquid fuel, which is the primary function of the tank. To make the steel tank systems fit for their function; the tanks are made in accordance with the UL standard 142 and ULC standard S601. The UL/ULC standards cover all the aspects of tank construction including material specification, fabrication, welding and testing. The tanks are listed in accordance with UL/ULC Standards and carry UL/ULC labels as such.

b. At the fabrication shop, the tanks undergo a number of quality control and test procedures including a 24 to 48 hour pressure test at five (5) psig.

2. Secondary Containment

a. The second stage of manufacturing consists of wrapping the steel tank with a minimum of 1/4" thick Styrofoam (foam) insulation and an impervious barrier of 30 Mil high density polyethylene membrane (poly). The 30 Mil poly provides containment for the remote probability of fuel leak through the steel tank. A leak detector pipe terminating in the secondary containment provides a positive-proof that the tank is not leaking.

b. Another advantage of the 30 Mil poly is that it shields and protects the steel tank exterior from coming in direct contact with concrete and thus minimizing the potential of tank external corrosion.

Figure No. 1

3. The Concrete Vault

The next step of manufacturing a ConVault® tank is to encase the tank in a six (6) inch thick reinforced concrete vault. Simply put, the six inches of concrete is poured on all sides bottom and top of the tank in one step and hence the phrase "monolithic". This process assures that there are no joints and no heat sinks in the concrete to carry heat from a fire into the primary containment.

The concrete pouring process also goes through a strenuous quality control procedure to make sure the ConVault® tank withstands its ultimate performance test, the two (2) hour fire test. ConVault® tanks are listed by UL 2085 standard and ULC/ORD 142.16 as fire resistant/insulated and protected tank.

4. Coating and Finishing

At the final stages of manufacturing, the concrete exterior of the tank is vacuum coated using a two-part water based epoxy paint to protect the tanks from the inclement weather conditions. Concrete exterior can also be produced in exposed aggregate with a clear coat of sealant or in STO finish. The entire pipe fittings and nipples on the tank are powder-coated to protect them from corrosion.

D. Additional features

The following is a list of some of the major features and advantages of the ConVault® tanks:

1. Complying with Environmental and Fire Safety Requirements

a. ConVault® tanks meet applicable safety requirements for secondary containment, leak monitoring, and spill protection. ConVault® tanks are approved by fire officials in most local jurisdictions. They are currently in use nationwide.

b. ConVault® tanks meet NFPA 30 and 30A , UFC, BOCA, SBCCI model fire codes safety standards. The units comply with the 1996 Uniform Fire Code Standard for the aboveground storage and dispensing of motor fuels.

c. ConVault® tanks are certified by the California Air Resources Board for Balanced Phase 1 and phase 2 Vapor Recovery including methanol and ethanol.

2. UL/ULC Listed

a. The ConVault® tanks have the following UL and ULC listings:

1. UL - 142, aboveground tanks for flammable and combustible liquids.
2. UL - 2085, two hour furnace fire test and two hour simulated pool fire test for insulated tank.
3. UL - 2085, insulated and protected secondary containment aboveground tanks for flammable and combustible liquids
4. UL - 2085 and UFC SECTION (79-7) ballistic and vehicle impact test for protected tank.
5. UL – 2085/UL CAN ORD-C 142.16 Non-Metallic Secondary Containment and Venting by Form of Construction.
6. UL – Subject 2244 Systems Listing for Motor Vehicle Fuel Dispensing.
7. UL CAN/ORD - C 142.16, protected aboveground tank assemblies for flammable and combustible liquids.
8. UL CAN/ORD - C 142.5, concrete encased aboveground tank assemblies for flammable and combustible liquids.
9. UL CAN/ORD - 142.16, the furnace burn requirements for two hour fire rating.
10. UL CAN/ORD - 142.5, the open (pool) fire testing for two hour flammable liquid fire test.

3. Overfill Protection

Tanks can be provided with two or more of the following methods to protect them against overfill: a) direct reading level gauge at the tank which is visible from fill pipe location; b) valve located within fill-pipe access to close automatically at a specified fill level; c) audible high level alarm activated by a float switch at a specified fill level.

4. Venting

The ConVault® tank systems are furnished with a 2 inch normal vent and an emergency pressure relief system. The standard emergency relief system furnished with the tank normally opens if the tank pressure exceeds 1/2 psig. The tank systems conform to model fire codes and UL/ULC Standards for venting.

5. Support Legs

Vaults have concrete support legs of unitized monolithic construction that provide visual inspection capability. Tanks do not require cathodic protection system as no steel part of the tanks comes in direct contact with the ground.

6. Thermal and Corrosion Protection

The tank construction includes thermal insulation to protect against temperature extremes and corrosion by separating the steel tank from the concrete. No part of the steel tank comes in direct contact with concrete or any other corrosive material.

7. Spill Containment

The tank system includes a 5 to 15 gallon, powder-coated UL-Listed and patented, spill containment surrounding the fill pipe. The spill container is equipped with a normally closed hand operated valve that can be actuated to drain the spilled fuel liquids into the steel tank.

8. Vehicle impact resistance

ConVault® tanks are designed to have a low center of gravity that can withstand vehicle impact and tipping during earthquakes and other natural disasters. ConVault® tanks have withstood even phenomenon tests such as C-130 aircraft impact at Ft. Dobbins in Georgia, Hurricane Andrew and the 1989 Loma Prieta earthquake.

9.Bullet Resistance

ConVault® tanks withstand bullet resistance tests in compliance with UFC SECTION (79-7). APPENDIX # A-II-F-1.

10. Non-Metallic Secondary Containment and Venting by Form of Construction.

The UL 2085 Standard listing officially recognizes Convault tank as having a secondary containment that is non-metallic and that vents by form of construction. This eliminates the need for an emergency-venting device on the secondary containment.

11. California Air Resources Board (CARB) Certified

ConVault AST's are CARB certifies for use with Phase I and Phase II vapor recovery systems under Executive Order G-70-116 and revisions A through F. California is recognized as the national air quality expert and, having passed all field examinations by CARB, ConVault AST's are generally regarded as having met the severest air quality compliance standards.

More information can be found at their website: http://www.arb.ca.gov.

• .NOTICE: Aboveground Storage Tanks (AST) should be evaluated to determine acceptability for continued use after fire exposure, physical damage, or misuse.

E. Tanks’ Weights and Dimensions

Figures No. 2, 3 and 4 give nominal capacities, the outside dimensions, general fittings layout and approximate weights of some popular ConVault® systems. These figures can help you in your planning for the future fuel storage requirements. Contact your ConVault® distributor for accurate weight of tanks to help you in arranging for proper equipment for unloading and setting of tanks.

 

Figure No. 2

Tank Weights and Dimensions *
Single Primary Tank

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.

• Double-wall steel tanks are optional and external dimensions are identical to single wall tank.
• Nipple layout and designs vary according to customer needs.

  *NOTE: These are nominal weights of the tanks. Check with your distributor/salesperson for accurate weights.

Figure No. 3

Multi-Compartment Tank Weights and Dimensions *
The "D" Design

• Nipple layout and design vary according to customer needs.
  

  *NOTE: These are nominal weights of the tanks. Check with your distributor/salesperson for accurate weights.

Figure No. 4

Multi-Compartment Tank Weights and Dimensions *
The "E" Design

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• Nipple layout and design vary according to customer needs.

  *NOTE: These are nominal weights of the tanks. Check with your distributor/salesperson for accurate tank weight.

F. Permits and Approvals

Installation of fuel/oil storage systems requires approval process from various government agencies. Table 1 shows typical approval process and documents needed. Specific local or AUTHORITIES HAVING JURISDICTION requirements may slightly differ for different locations, but the list is a good reference and a guide for your permits requirements.

Table 1

PERMITS AND APPROVALS

Table No. 2

CODES, REGULATIONS, AND GUIDELINES

Aboveground fuel storage tanks fall under a variety of governmental jurisdictions; therefore the following reference is provided as a general outline. You may be subject to different legislation and governing bodies in your specific locale. A preliminary investigation must be conducted to thoroughly understand the controlling factors prior to the utilizing the product in your specific area.

FEDERAL REGULATIONS

40 CFR 112

US Coast Guard

Environmental Protection Agency (EPA)

Occupational Safety and Health Administration (OSHA)

STATE REGULATIONS

Federal regulations are referred to the governor of each state with the instructions that delegated duties to subordinate state agencies must provide a written plan on how the individual state will comply with the EPA’s enforcement activities.

CODES AND STANDARDS

NFPA 30, 30A, and 31 Flammable and Combustible Liquid Code

ICBO Uniform Fire Code section 79 APPENDIX A - II - F (UFC)

Building Officials and Code Administration (BOCA)

Underwriters Laboratories (UL)

Underwriter’s Laboratories Canada (UL CAN/ORD)

Southern Building Code Congress Institute (SBCCI)

ENVIRONMENTAL CAVEAT

Several regulatory agencies have been integrally involved in the development of the ConVault® aboveground storage tanks.