1. Trends with Shop-Fabricated Storage Tanks
Wayne Geyer
Steel Tank Institute
November 18, 2013

2. Who and What is STI/SPFA?
Association of 180 fabricating and affiliate companies of steel construction products – shop-fab tanks, field erect tanks, pipe, pressure vessels and other special fabricated products
STI members account for nearly all of the total shop fabricated underground steel storage tank production capacity in North America

3. 2012 Annual Product Awards: Steel Fabricated Products
Driving traffic to our website, promoting steel and sustainability.
Please take a look!
Any questions?
Thank you for this opportunity to share our efforts with you.

4. Steel Fact Sheets

5. What does the Steel Tank Institute do?
UST and AST tank technologies
Industry standards and recommended practices
License manufacturers to build tanks to STI specifications
Quality control
Information resource
Certification
4 – 50,000 Gallon Permatanks Installed at Northwestern Univeristy

6. STI Tank Registration
Every tank built with an STI labeled is inspected by tank fabricator to meet STI specification
Tank is “registered” with STI
STI maintains database with over 400,000 entries

7. Tank Performance Evaluation
All STI labeled UST’s subject to 3rd party warranty
STICO Mutual has strong claims management program
STI gets feedback on quality and performance

8. Education, Research, & Advocacy

9. STI Certification Programs
927 Certified SP001 Aboveground Storage Tank Inspectors
484 Certified Cathodic Protection Testers
Over 130,000 sti-P3 tanks tested for cathodic protection through WatchDog program
NEW: On Line Learning Program
T*I*M Tank Integrity Management

10. STI Shop-Fabricated Tank Programs
> 100 tank shops licensed and inspected
14 tank fabrication standards
19 recommended practices for testing, installation and inspection
NEW: R111 Storage Tank Maintenance
Under Development: SP131- UST Inspection, Repair, & Modification

11. Years in Number after 1970

12. Coatings Provide Corrosion Protection

13. Underground Storage Tanks
Primarily used at service stations today
Tanks are getting larger
STI Database
Average capacity in 2013 for jacketed tank exceeds 15,000 gallons
25 years ago, the typical UST at a service station was 8000 – 10,000 gallons

14. Compartment Tanks
Compartment tanks have become very common for both UST’s and AST’s
Multiple fuel types can be stored within one tank unit
Provides user/owner versatility as more fuels develop

15. Underground Storage Tanks
UL 58 is the principle standard for steel tank construction – single wall and double wall steel
UL 1746 is the principle standard for corrosion control and for jacketed (non-metallic outer wall) tank construction

16. Underground Storage Tanks
Regulations require all tanks incorporate secondary containment
Today, jacketed tanks are favored by many buyers as outer containment provides a corrosion barrier and secondary containment
Other corrosion systems use two walls of steel

17. Fabricating Steel Secondary Containment
After the primary tank is built and tested, the outer wall is fabricated atop the primary tank.
The second wall is intimately wrapped atop the primary tank wall.

18. Testing the Interstice
Most fabricators will test the interstice by bleeding air from a 3-5 psi pressurized inner tank into the secondary tank. The volume of the interstice is very small and can get pressurized rapidly.
Access to the interstice can be fabricated in different ways

19. Production Test to Verify Both Walls are Tight
Upon completion of production testing of the interstice with positive air pressure, and soap testing the welds of the secondary containment, all air is released.
Then a vacuum is pulled within the interstice and monitored by the fabricator for tightness over time.

20. Preparing the Tank for Delivery
After ancillary equipment installed, coatings applied, etc. the tank is made ready for shipment.
Fabricators apply a vacuum into the interstice of secondary containment tanks.

21. Interstitial Vacuum
After the vacuum is applied, the tank is held in storage until it is made ready for delivery
The vacuum remains on the tank during storage, delivery, and during much of the installation.
An easy view of the vacuum gauge to verify retention of the vacuum assures that both walls remain tight.

22. Tank Compatibility - Biofuels
E10, E15, E85, B2, B20, B100
Steel Tank Manufacturer Certification Statements
STI Web Site
Performance
Tanks are Cleaner – Sludge
Biodiesel Shelf Life
Water Concerns
Phase Separation - Ethanol

23. Recent Events Biofuels
Sumps
EPA ORD Research
NIST Research
Publications
“Compatibility of UST Systems with Biofuels,”
Published by ASTSWMO
Case Studies
Research and Work Groups
Underground tanks storing E85

24. Ultra Low Sulfur Diesel Issues
Corrosion of metal components within FRP tanks storing ULSD
Clean Diesel Fuel Alliance supported research from Battelle Labs - completed in 2012
Further studies under consideration
STI Research
Tanknology hired to visually examine the insides of steel and FRP ULSD tanks
Fuel samples extracted and tested
Example – Las Vegas service station tanks under same owner
FRP tank vapor control fitting – top right photo
Steel tank vapor control fitting – bottom right photo

25. Inspection and Maintenance of the Tank System

26. Inspection and Maintenance
STI R111
Storage Tank Maintenance
STI SP001 AST Inspection

27. Aboveground Storage Tanks
Cylindrical
Rectangular
Vertical
Horizontal
Double Wall
Diked
Fire-protected
Gen-Base
FieldErected

28. Aboveground Storage Tanks
Most popular choice for shop-fabricated tanks for:
Fleet motor vehicle fueling applications
Fuel for emergency power generators
Bulk oil and chemical storage
Secondary containment

29. Aboveground Storage Tanks
UL 142 is the principle standard for steel tank construction – single wall and double wall steel.
UL 2085 is the principle standard for two hour fire protected tank construction.

30. Aboveground Storage Tanks
Secondary contained shop-fabricated steel tanks are preferred:
Serves as spill control to meet fire codes
Meets SPCC rules with proper use of overfill prevention equipment
Double wall construction preferred over diking

31. AST’s with 2-Hr Fire Test Ratings

32. Protected AST’s Protected aboveground tanks preferred when:
Installed in close proximity to buildings & property lines
Dispenser mounted on tank
Minimize fire safety hazards
Meet codes for motor vehicle fuel dispensing

33. SPCC – AST Inspections
EPA references STI SP001 standard for smaller tank inspection and integrity verification
Category 1 preferred
Double wall tanks can be easily tested with vacuum to prove containment integrity
Category 3 – Higher Risk to Environment

34. Facilities with a mix of tanks require one type of inspector

35. Release Prevention Barrier (RPB)
Liquid containment barrier
Under the AST
Diverts leaks toward the perimeter of the AST where they can be easily detected

36. Risk Matrix Concept – SP001
More Risk
Tank Size
Category 1
Category 2
Category 3
Shop built tanks P
P, E&L(10)
,000
[P, E&L(5), I(10)] or
[P, E(5) & L(2)]
5, ,000
P, E(20)
[P, E(10)& I(20)]
[P, E(5) & L(10)]
[P, E(5) & L(1)]
30, ,000
P, E&L(5), I(15)
P, E&L(5), I(10)
Field erected
P, E(5), I(10)
Portable containers
P **
More Risk

37. Category 1 – Secondary Containment and CRDM
Double-wall Tank Tank in a
with Overfill Prevention Concrete Dike

38. Wayne Geyer
steeltank.com