What Makes a Tank Worthy of an STI Label. Wayne Geyer, STI/SPFA September 16, 2013 Denver, Colorado

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1 What Makes a Tank Worthy of an STI Label Wayne Geyer, STI/SPFA September 16, 2013 Denver, Colorado

2 Who and What is STI/SPFA? Association of 180 fabricating and affiliate companies of steel construction products shopfab 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

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 Education, Research, & Advocacy

7 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

8 STI Shop-Fabricated Tank Program > 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 6 UL files with hundreds of volumes & 4 SWRI technology programs

9 Steel Storage Tank Standards Underwriters Laboratories UL 58: construction of the underground steel tank and secondary steel containment UL 1746: construction of the corrosion control and jacketed tank UL 142: construction of the aboveground steel tank and secondary steel containment Steel Tank Institute Uses UL 58 & UL 142 as basis for the fabrication of the steel primary tank STI Dual Wall Tank Std. Corrosion control Sti-P3: cathodic protection ACT-100 composite & ACT-100-U urethane Permatank: FRP jacketed steel tank

10 Steel Specifications UL and STI standards specify steel requirements ASTM A 1011 ASTM A 36 Carbon Equivalency <0.53 Steel is purchased by fabricator in plate form or in coil form from steel mills or steel service centers

11 Steel Specification Steel mills carefully control composition of steel Carbon is added to iron to form steel. Addition of alloy and chemicals and the process in which it the steel is made gives the steel its desired properties.

12 Steel Specification Carbon is kept below 0.3%. Higher carbon content adds strength but reduces weldability and formability. Addition of manganese and silicon provide added strength.

13 Desirable Properties of Steel Yield Strength Tensile Strength Flexural Strength Ductility Hardness Resistance to Impact Formed into any Shape and Size

14 Tank Shell (Barrel) Flat plate must be rolled to the specified diameter Each plate will be obtained by the fabricator with a specific width, length, and thickness.

15 Tank Shell (Barrel) To achieve the desired diameter, the plate length must be pi (3.1415) * diameter. For D=10, the plate must be slightly longer than Once the plate is formed into a cylindrical shape, the resultant ring is moved to a location where the two ends can be welded together.

16 Tank Shell (Barrel) This picture depicts the placement of a second ring adjacent to the first ring for fit-up and welding. The fit-up is extremely important to assure a good weld joint. These two rings are not yet aligned.

17 Joints can be Butt Welded Lap Joint Welded Joggle Joint Welded Other Welding made via Submerged Arc Flux Core Arc Weld Gas Metal Arc Shielded Metal Arc Welding

18 Attaching the Heads After all rings have been welded together, bulkheads inserted, then the final outside tank head can be welded onto the shell or barrel. Fit-up is an important process in building a tank to assure a good weld.

19 All atmospheric tanks are tested with air pressure. Production Tightness Horizontal cylindrical tanks are tested at 5 psi. Vertical tanks at 3 psi. Rectangular tanks are tested at a pressure based on its UL performance test, normally 3-5 psi. Performance Test

20 Locating Pinholes All welds are further tested during the pressure test with a soapsuds solution. If the weld has a pinhole, air will escape at the pinhole and a bubble is easily seen Welds must be repaired and proven tight.

21 Adding Secondary Containment Most underground storage tanks and many aboveground storage tanks are built with secondary containment. Many of these tanks use two walls of steel, although underground tanks can be built with a non-metallic wall, also called a jacketed tank.

22 Adding Secondary Containment After the primary tank is built and tested, the outer wall is fabricated atop the primary tank. The second wall is placed intimately atop the primary tank wall. Such an intimate wrap is called a Type I containment.

23 Interstitial Monitoring Port Some fabricators will install a pipe within the primary tank that is used to monitor the interstice for leaks. Others install the monitoring pipe outside both tank walls. Both methods allow a liquid sensor to be inserted into the low point of the interstice for liquid monitoring.

24 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

25 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.

26 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

27 35,000 T a n k 30,000 25,000 U n i t s 20,000 15,000 10,000 B u i l t 5, sti-p3 Tank Installations Years in Number after 1970

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

29 STI Quality Control Program Random inspections performed by qualified STI inspectors on quarterly basis Mandatory attendance at Quality Control meeting Quality awards

30 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

31 31 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

32 32 Ultra Low Sulfur Diesel Issues Corrosion of metal components within steel and 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

33 Inspection and Maintenance of the Tank System

34 Inspection and Maintenance STI R111 Storage Tank Maintenance STI SP001 AST Inspection

35 Perpetual Tank System Life 1986 Sti-P3 E85 Tank Removed in 2013 No Leaks Manufacturer s Warranty 10 Year, 30 Year Steel Capabilities as a Material Desirable Operations Routine Maintenance Tank Inspection Fuel Usage Corrosion Protection Component Life

36 STI/SPFA Water Industry Century Club Dothan, Alabama Dixie Tank Built in 1897 City landmark Civic pride 116 years old Remains in operation

37 UL Tank Standards Update A Reader s Digest Summary of UL Standards Work in Recent Time

38 UL STP 58 STP = Standards Technical Panel STP 58 covers all UST standards UL 58 UL 1746 and UL 1316 In March 2012, UL called a meeting to start the process of updating the UL standards

39 STP 58 UL announced that scope of all standards will remain as is Flammable and Combustible Products until UL completes their research on fuels. Task groups were formed to develop proposals for both UL 58 and 1316 Decided to start ballot process with 1746 because it had been a consensus standard.

40 UL 1746 On Sept 21, 2012, UL posted comments for preliminary review. This is the first step in the UL process to update a standard. UL automatically posted for review all of the older, outstanding items Other items were also requested for change, totaling 17 topics for committee review

41 UL 1746 Agreement to move to ballot Of these 17 the committee agreed that 9 topics should move forward to the ballot process. Update fuels to reflect modern fuels such as biodiesel Add interstitial communication test Revise leak test Update glossary terms Update installation instructions In addition, proponents may move to ballot without preliminary consensus if they choose.

42 New UL 1746 Update Fuels Addition of Biodiesel Blends Test fuel proposed is aggressive blend Includes water and acid in the test fuel

43 Modification UL 1746 Interstitial Communication Test UL 1746 is the only UST standard to require a communication test Purpose is to verify that interstitial space is capable of communicating a leak Current test states tank must be buried Proposal is to allow additional options for testing

44 Modification UL 1746 Revise Production Leakage Test Proposal to add requirements to how tanks are tested in the shop Standard currently allows both vacuum and air pressure test Standard procedure nowadays for steel tanks is to ship double wall tanks with vacuum on interstice Proposal to make vacuum test more stringent

45 UL 58 and UL 1316 After 1746 was issued for preliminary review, work on 58 and 1316 came to a halt Time required Some prefer to see how issues resolved in 1746 UL has no timeframe for reviewing these standards.

46 Most Recent Editions UL 1316 last issued 1/4/1994 with technical revisions dated April 2, 1996 UL 58 last issued 12/13/1996 with technical revisions dated July 27, 1998 UL 1746 last issued January 17, 2007 as a consensus document.

47 UL Voting Process Preliminary Review Balloting If consensus reached, but Negatives or Comments received, proposal submitter has to respond as follows: a) Accepting the Comment, b) Rejecting the Comment, c) Accepting the Comment in principle but with changes in the proposed wording, d) Accepting the Comment in part, e) Accepting the Comment in principle and in part, f) Acknowledging the comment (when the commenter agrees with the proposal), or g) Answering the comment (when the comment poses a question, but doesn t advocate a particular technical revision). Then item is re-balloted

48 UL 142 Steel ASTs Feb 3, 2012 UL issued bulletin starting the process to revise UL Proposals were issued Editorial items included in this number 15 items reached consensus Waiting to be published A few of the items that reached consensus follow

49 Modification UL 142 Vertical Tanks Proposal approved to change the language back to how it read prior to 2007 Add a limitation on tank capacity, 50,000 gallons Remove limitation on tank diameter

50 Deletion UL 142 Markings Deletion of markings for tanks on supports and diked tanks On Supports Open Top Closed Top

51 New UL 142 Requirements for Minor Accessories 38B Minor Tank Accessories 38B.1 If provided, minor accessories intended for factory assembly or field installation to the tank shall comply with the requirements in 38B.2 and 38B.3. 38B.2 Mounting brackets for small equipment shall not exceed 4.0 ft2 (single side projected area), and shall be constructed of at least inch thick steel. Mounting brackets greater than 4.0 sq ft2 shall comply with the Static Load Test in paragraph The brackets and supporting structure shall be welded to the tank, or provided with bolted connections that are welded to the tank.

52 Clarification UL 142 with Respect to Venting 8.4 A vent opening that provides for emergency venting shall have a capacity not less than that specified in Table 8.1. A vent opening that provides for both emergency and normal vents shall also have a total venting capacity not less than specified in Table 8.1, in addition to the requirements of paragraph 8.2. Emergency vents are not prohibited from use for normal venting of the primary tanks if the tanks are marked as specified in (e).

53 New UL 142 Requirement for Sumps 38.2 As an option, sumps no larger than 18 inches in with a maximum 24 inch diameter nor more than 6 inches in and maximum 12 inches depth shall be permitted in primary and/or secondary tanks along the bottom center line. The thickness of the sump material shall, at a minimum, be the same thickness of the tank shell or bottom, depending on the location of the sump and the type/orientation of the tank All internal welds are to be full seal welds Sump welds shall be a minimum 6 inches from a head or bulkhead weld.

54 Clarification- UL 142 Production Testing Some AHJ s as well as tank purchasers are confused. The intent of UL 142 has been misinterpreted because some readers believe that all of the one time performance tests should be done as production tests on every tank Each primary and secondary containment tank, before painting, shall be tested by the manufacturer and determined to be tight against leakage using the method of the Tank Leakage Test, Section 39 described in paragraphs 39.1, 39.2, and 39.3.

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56 50,000 Gallon Double Wall ACT-100 Tanks Installed at O Hare Airport wgeyer@steeltank.com