August 5 , 2009 1

Task Order No. 3003

– Task 2, Subtask d

– Current Equipment Use Technical Directive No. 5

Summary for Current Equipment Use Analysis This report summarizes the methodology and findings of the review of underground storage tank (UST) equipment currently in use for federall y regulated USTs (hereafter referred to as “tanks”) in 23 states. Methods E 2 Inc. reviewed state UST databases obtained from a search of 56 state and territory UST Web sites and direct contact with nine state UST agencies for informati on regarding tank construction, pip e construction , and release detection ty pe for federall y regulated tanks

. Databases were queried for specific information requested by OUST. Thirteen states provided data that indicated which tanks were federally regulated. For states that did not specify which tanks were federall y regulated, rules based on tank volume and ty pes of substances contained in the tanks were applied to the data to estimate which tanks were federall y regulated. Complete results of this analys is can be found in the following appendices: Appendix A: Tank Ty

pe - Currentl y In Use Appendix B: Pipe Ty

pe - Currentl y In Use Appendix C: Tank Leak Detection

- Currently In Use Appendix D: Pipe Leak Detection

- Currently In Use Appendix E: Other Ch aracteristics

- Currently In Use Appendix F: Interstitial Monitoring

- Currently In Use Appendix G: Tank Ty

pe - Temporarily

Out Of Service Appendix H: Pipe Ty

pe - Temporarily

Out Of Service Appendix I : Tank Leak Detection

- Temporaril y Out Of Service Appendix J: Pipe Leak Detection

- Temporaril y Out Of Service Appendix K: Other Characteristics

- Temporaril y Out Of Service Appendix L : Interstitial Monitoring

- Temporarily Out Of Service An overall summary

of the data , including rules applied and data limitations, is contained in the Results and Data Limitations section s . Percent usage of the most commonly used equipment and materials was calculated for each category . Raw percentages within each category may not add up to 100 percent because they are based on the number of tanks in each state for which that particular type of equipment is possible. For example, some states have “NA” in place of a specific equipment type. In these instances, the total number of tanks for that state is not included in the total number of tanks in the denominator for that particular equipment ty pe. The normalized percentage was calculated b y dividing the un

- normalized percentage by the total of the un

- normalized percentages

. Normalized percentages are presented in thi s report and may not add up to 100 percent, due to rounding . Results are organized by the following topics: tank ty pe, pipe ty pe, tank leak detection, pipe leak detection, other characteristics, and interstitial monitoring.August 5 , 2009 2

Results Tank Type Of the 23 states researched, all but Hawaii had information available regarding whether tanks were single

- walled or secondarily contained. Tanks at currentl y in

-use facilities (hereafter referred to as “CIU”) totaled 318,544 tanks, while temporaril y out of service facilities (hereafter referred to as “TOS”) totaled 19,713 tanks. Most tanks are single

- walled (Table 1). Table 1. Percent of single v ersus secondaril y contained tanks Tank status Single

- walled Secondarily Contained Unknown CIU 69.89% 28.81% 1.30% TOS 78.89% 9.13% 11.98% Total 70.41% 27.67% 1.92% Overall, 4 5

. 45 percent of tanks are made of steel, 36

. 16 percent are fiberglass, 13.64 percent are composite and 2. 50 percent are jacketed (Table 2). Lined steel tanks make up 5.19 percent and cathodically

protected steel tanks make up 36.53 percent of all tanks. Table 2. Overall m aterial of construction among single

- walled and secondarily contained tanks Tank status Steel Fiberglass Com posite 1 Steel

jacketed Other2 Unknown CIU 43.92% 37.17% 14.10% 2.6 0% 0.28% 1.93% TOS 72.80% 18.06% 5.58% 0.56% 0.45% 2.55% Total 45.45% 36.16% 13.64% 2.50% 0.29% 1.96% 1 Examples of “composite” include steel with fiberglass and urethane cladding. 2 An example of “other” is concrete. Twenty

- one states reported the ty p e of construction used among all single

- walled tanks. Wisconsin reported the number of single

- walled versus secondaril y contained tanks but did not specify type of construction. Most single

- walled tanks are made of steel (Table 3 ). The second most common material used is fiberglass. Table 3 . Material of construction among all single

- walled tanks Tank status Steel Fiberglass Com posite 1 Other2 Unknown CIU 55.29 % 30.94% 12.17% 0.35% 1.25% TOS 76.89% 14.93% 5.07% 0.48% 2.63% Total 56.73% 29.87% 11.70% 0.3 6% 1.34% 1 Examples of “composite” include steel with fiberglass and urethane cladding. 2 An example of “other” is concrete. Table 4 summarizes the six ty pes of construction among single

- walled tanks made of steel. The most common classifications for tanks were “cathodic protection unknown” and “with general ty pe of cathodic protection.” The following rules were applied to all tanks using steel:

 The category

of “cathodic protection unknown” includes steel tanks with no ty pe of cathodic protection marke d. This category may include both tanks without cathodic protection and those that have cathodic protection, but it is not indicated in the state database.August 5 , 2009 3

 The category

of “with general type of cathodic protection” included steel tanks with both impressed current and galvanic anode cathodic protection as well as steel tanks with an unspecified type of cathodic protection. In this instance, tanks were not counted in the “with impressed current cathodic protection” or “with galvanic anode cathodic protection” categories.
 Tanks marked as having “internal lining” and “galvanic anode cathodic protection” or “impressed current cathodic protection” were counted as “with internal lining and cathodic protection.” In this instance, tanks are not counted in the “with impressed current cathodic protection” or “with galvanic anode cathodic protection” categories. Table 4 . Ty

pe of construction among single

- walled tanks using steel 1

Tank status Cathodic

protection unknown With

im pressed current cathodic protection With

galvanic anode cathodic protection With general

ty pe of cathodic protection With

internal lining With internal

lining and cathodic protection CIU 14.18% 19.86% 20.51% 31.86% 4.42% 9.17% TOS 39.1 4 % 12.82% 16.53% 25.45% 1.90% 4.16% Total 16. 4 6 % 19.22% 20. 13% 31.29% 4.19% 8.72% The same 21 states that reported the type of construction used among all single

- walled tanks also reported the typ e of construction used among all secondaril y contained tanks. Most of the secondaril y contained tanks were made of f iberglass (Table 5 ). Composite was the second most common material used. Table 5 . Material of construction among all secondarily contained tanks Tank s tatus Steel Fiberglass Com posite 1 Steel

jacketed Other2 Unknown CIU 16.34% 52.27% 18.77% 8.92% 0.1 2 % 3 .58% TOS 37. 4 4 % 45.08% 10.02% 5.44% 0.15% 1.87% Total 16. 7 3 % 52.15% 18.60% 8.85% 0.12% 3.54% 1 Examples of “composite” include steel with fiberglass and urethane cladding. 2 An example of “other” is concrete. Table 6 summarizes the six ty pes of construction among secondaril y contained tanks using steel. The most common classification is “with galvanic anode cathodic protection.” The same rules that applied to single

- walled tanks using steel described above were applied to secondaril y contained tanks u sing steel.

1 The di s tribution of cathodic protection types among tanks and pipes were normalized based on the normalized percentage of all construction types. Those cathodic protection types that were not tracked in all state databases may be overstated, as the normalization applies the percentage calculated for tanks and pipes in states that track these cathodic protection types to tanks and pipes in states where it is not.August 5 , 2009 4

Table 6 . Ty

pe of construction among secondarily contained tanks using steel

Tank status Cathodic

protection unknown With

im pressed current cathodic protection With

galvanic anode cathodic protection With general

ty pe of cathodic protection With

internal lining With internal

lining and cathodic protection CIU 11.78% 4.56% 54.10% 28.72% 0.40% 0.44% TOS 6.03% 4.16% 60.61% 28.22% 0.33% 0.65% Total 11.56% 4.53% 54.25% 28.82% 0.39% 0.45% Pipe Type Of the 23 states researched, 20 states had inf ormation available regarding the ty pe of pipes used. The Massachusetts, Ohio, and Wisconsin databases reported no information on piping. Currently in

-use tanks with pipe totaled 274 , 022 while 18 , 870 tanks with pipes were reported as TOS. Most of the pip es reported are single walled (Table 7 ). The following rule was applied when counting the number and type of pipes:

 Missouri and Mississippi tracked multiple piping records for each tank and all of the multiple records were counted in pipe totals. Table 7 . Percentage of single

- walled versus secondarily contained pipes Tank status Single

- walled Secondarily contained Unknown CIU 61.63% 36.28% 2.09% TOS 75.62% 10.06% 14.32% Total 62.54% 34.59% 2.87% Most pipes are made of fiberglass (Table 8 ). Steel i s the second most common material for single

- walled pipes and flexible plastic is the second most common material for secondarily contained pipes. Table 8 . Material of construction among single

- walled and secondarily contained pipes Tank status Steel Fiberglass Flexible plastic Other 1 Unknown All single

- walled and secondarily contained pipes CIU 18.08% 58.13% 13.37% 2.16% 8.25% TOS 47.78% 39.40% 3.73% 1.19% 7.89% Total 19.78% 57.05% 12.82% 2.11% 8.23% Single

- walled CIU 26.6 5 % 62.72% 4.32% 1.97% 4.34% TOS 51.81% 38.15% 1.20% 1.05% 7.79% Total 28.6 2 % 60.80% 4.07% 1.90% 4.61% Secondarily contained CIU 3. 53 % 50.32% 28.76% 2.49% 14.91% TOS 17. 49 % 48.79% 22.78% 2.29% 8.65% Total 3.7 9 % 50.29% 28.64% 2.49% 14.79% 1 Examples of “other” include copper, p vc and iron. Overall, 19.78 percent of pipes are made of steel, 57.05 percent are fiberglass, and 12.82 percent are flexible plastic.August 5 , 2009 5

Of all single

- walled and secondaril y- contained pipes using steel, most do not have cathodic protection indicated in the databases (Table 9 ). However, in cases where impressed current cathodic protection is used for the tank, the same method of cathodic protection may be used for the piping. Of single

- walled and secondarily contained pipes that do have cathodic protection, most are classified as “with general type of cathodic protection.” The following rule was applied to pipes using steel:

 The category

of “with general type of cathodic protection” included steel pipes with both impressed current and galvanic anode cathodic protection as well as steel pipes with an unspecified type of cathodic protection. Table 9 . Ty

pe of construction among single

- walled and secondarily contained pipes using steel Tank status Cathodic

protection unknown With impressed

current cathodic protection With galvanic

anode cathodic protection With general type

of cathodic protection Single

- walled CIU 34.02% 26.55% 11.54% 27.89% TOS 61.7 8 % 14.65% 6.56% 17.01% Total 37.97% 24.86% 10.82% 26.35% Secondarily contained CIU 50.9 2 % 2.39% 8.89% 37.7 9% TOS 64.39% 3.18% 2.07% 30.36% Total 52.06% 2.46% 8.30% 37.18% Nine of the 23 states did not provide information regarding piping product delivery s ys tem ty

pe. Of the 14 states that did provide information, most pipes used a pressure delivery s ys tem (Table 10 ). Tanks with unknown product delivery types were removed and assumed to have the same distribution of pressurized, suction, and other types as was found in those where the type was known: 81. 21 percent, 17.30 percent, and 1.50 percent respectivel y. The following rules were applied to piping product delivery s ys tem ty

pes:

 Delivery

s ys tems marked as “no valve

– suction,” “valve

– suction,” “safe suction,” “unsafe suction,” and “u.s. suction” were included under the suction category

. Delivery systems marked as “gravity” or “manifold” were included under the “other” category

. The unknown category

includes delivery

s ys tems reporting multiple methods of delivery as well as “unknown,” “bulk product system , ” and blank cells. Table 10 . Piping product delivery s ys tem ty

pe Tank status Pressure Suction Other CIU 82.23% 16.36% 1.41% TOS 60.37% 36.53% 3.10% Total 81.21% 17.30% 1.50% Tank Leak Detection Of the 23 states queried, 17 states provided information regarding leak detection methods for tank s. A total of 348,017 tank leak detection instances were identified. Currently in

-use tanksAugust 5 , 2009 6

accounted for 94 percent of these instances. Automatic tank gauging was the most common leak detection method (Table 11 ). The following rules were applied to the data:

 For tanks using more than one method of leak detection, all methods were counted ;  Tanks marked as “tank tightness testing,” “inventory control,” or “other” were recorded as “other ; ” and
 When none of the specific leak types were selected, they were counted towards “unknown.” Table 11 . Percentage of leak detection ty pes among tanks with leak protection Leak Detection T ype CIU TOS Total Deferred 1.06% 0.95% 1.06% Inventory control and tank tightness testing 6.49% 8.44% 6.58% Manual tank gauging 3 .14% 3.32% 3.15% Automatic tank gauging 34.82% 14.72% 33.66% Interstitial monitoring 20.63% 5.18% 19.76% Ground water mo nitoring 5.47% 6.03% 5.51% Vapor monitoring 4.80% 8.44% 5.00% Statistical inventory reconciliation 12.90% 13.73% 12.96% Other 5.25 % 8.54% 5.44% Unknown 5.43% 30.65% 6.88% Pipe Leak Detection Of the 23 states queried, 16 states provided information regarding pipe leak detection for CIU pipes and 15 states provided that information for TOS pipes. A total of 437,490 pipe leak detection instances were identified. Currentl y in

- use pipes accounted for 94 percent of these instances. For piping using line leak detectors (LLDs), 5.38 percent of piping indicated using electronic LLDs and 10.72 percent indicated using mechanical LLDs (Tab le 12 ). Most state databases did not indicate the ty pe of LLD used. The following rules were applied to pipes with automatic line leak detection:

 Pipes not marked as “pressurized piping product delivery” were included in automatic line leak detection to tals when they specified electronic or mechanical line leak detection. This applied to data from 10 states.
 When pipes were marked as “pressurized” but not as having automatic line leak detection, they

were included in the “unknown” category . Pipes marke d as “autolineleak” and “auto line leak detection” were similarly categorized. This applied to data from 11 states. Table 12 . Ty

pe of leak detection among pipes with automatic line leak detection Tank status Electronic Mechanical Unknown CIU 5.53% 11.08 % 83.39% TOS 1.29% 0.58% 98.12% Total 5.38% 10.72% 83.90%August 5 , 2009 7

For periodic leak detection, most pipes use the line tightness testing method (Table 13 ). Interstitial monitoring is the second most common leak detection method among pipes. Table 13 . Ty

pe o f leak detection among pipes with non - automatic line leak detection Tank s tatus Deferred Line

tightness testing Interstitial

monitoring Ground

water monitoring Vapor

monitoring Statistical

inventory reconciliation Other Unknown CIU 4.74% 37.79% 19.52% 3.4 8% 5.08% 13.70% 4.65% 11.04% TOS 3.73% 20.26% 2.89% 2.83% 5.44% 10.86% 14.96% 39.02% Total 4.69% 36.51% 18.30% 3.43% 5.12% 13.49% 5.28% 13.19% Other Characteristics Of the 23 states queried, only Utah reported information regarding other characteristi cs of containment. Utah reported whether or not tanks had under dispenser containment and submersible turbine pump containment. Currently in

-use and TOS Utah tanks represent less than one percent of all tanks queried. Table 14 shows the percentage of under dispenser containment versus submersible turbine pump containment for tanks in Utah. Table 14 . Other characteristics of containment among tanks in Utah

Tank status Under dispenser containment Submersible turbine pump containment CIU 57 .10 % 59 .19 % TO S 22 .01 % 2 3.92 % Total 55.35% 57.43% Interstitial Monitoring Of the 23 states queried, 17 states provided information regarding interstitial monitoring among tanks, piping, or both tanks and piping. Table 15 shows the prevalence of interstitial monitoring among tanks and piping. Table 15 . Use of interstitial monitoring among tanks and pipes

Tank status Secondarily contained

tanks using interstitial mo nitoring Tanks with secondarily

contained piping using interstitial monitoring Systems with both secondarily contained tanks and secondarily contained piping using interstitial monitoring CIU 77.05% 49.32% 54.93% TOS 56.79% 29.06% 34.38% Total 76.64% 48.94% 54.60% Data Limitations The universe of USTs analyzed includes approximately 53 percent of the national total of active USTs. All ten regions are represented as well as small, medium, and large states. Due to the lack of data available for Florida and California, secondary containment totals may

be underestimated if results are extrapolated to the nation as a whole. Utah is the only state anal yz ed that tracks information on under dispenser containment and submersible turbine pumpAugust 5 , 2009 8

containment , so it is probably not appropriate to extrapolate these totals to the national universe of tanks. Due to varying database structures among the states, it was not possible to report a number of construction ty

pes in some states (e.g., in twelve of the 23 states anal yz ed, a secondarily contained tank assignment precluded the assignment of impressed current cathodic protection), so those ty

pes may be underreported. To compensate, percentages reported for each type are calculated as a percentage of the total tanks in only those states where it is possible to report a particular type of construction.