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Task Order No. 1010 – Subtask A1-06C 

Technical Directive No. 36

Summary of Key Data from State Public Record Postings

E2 Inc. compiled available data from 45 state and territory public record postings into an Excel 

file (Appendices 1 through 9) and calculated overall totals and percentages from these data. Data 

on federally regulated USTs were included in this analysis. This report provides a summary of 

key results and includes the following appendices:

1. General Information

2. Source of Release

3. General Cause of Release

4. Cause of Release from Tank

5. Cause of Release from Piping

6. Cause of Release from Dispenser

7. Cause of Release from STP

8. Cause of Release from Delivery

9. Cause of Release from Other

Methods

Public record data from the following 11 states and territories were not available for this 

analysis: Alaska, American Samoa, Florida, Guam, Iowa, Massachusetts, Nevada, New Mexico, 

Oklahoma, Puerto Rico, and Wyoming. With available public records, the numbers of USTs and 

facilities, inspections, compliance, and confirmed releases for each state and territory were 

compared to values from EPA’s Corrective Action Measures - Fiscal Year 2008 End of Year 

Activity Report. In addition, for each state or territory, source and cause information for releases 

was categorized and analyzed. The following general rules were applied to assign data to source 

and cause categories:

 The OUST Subject Matter Expert was consulted when source and cause categories 

provided in public records did not match those included in this analysis.

 For public records that do not report “unknown” sources and reported a number of 

confirmed releases greater than the source total, the difference between the number of 

confirmed releases and the source total was assigned as “unknown” sources.

 All releases caused by spills and overfills from tanks were moved to the delivery problem 

source.

Results for General Information (Appendix 1)

Total and average values for inspections, compliance, and confirmed releases from the public 

record data are provided in Table 1. Inspection frequency was calculated by dividing the number 

of facilities by the number of inspections; facilities in compliance was calculated by multiplying 
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the number of facilities by the compliance rate; and the release rate was calculated by dividing 

the number of confirmed releases by the number of USTs.

Table 1: Total and Average Values from Public Record Analysis

Total 

Number 

of 

USTs

Total 

Number 

of 

Facilities

Average 

Number 

of USTs 

per 

Facility

Total 

Number of 

Inspections

Average 

Inspection 

Frequency

Total 

Number of 

Facilities in 

Compliance

Total 

Number 

of 

Confirmed 

Releases

Average 

Release 

Rate

520,371 190,236 2.74 69,537 2.74 123,529 5,751 1.13%

There were some discrepancies between the values in public records and the EPA FY08 

Corrective Action Measures; overall, these differences were small. The public records for New 

Jersey and Wisconsin did not include the information needed to complete Appendix 1. 

Comparison of the number of USTs reported in public records with those from the FY08 

Corrective Action Measures revealed that most values were similar between the two reports. 

The largest difference was for Colorado, which reported 4,469 (56 percent) more USTs on its 

public record than in the FY08 Corrective Action Measures. This discrepancy likely resulted 

from the reporting periods used in the Colorado public record, which are greater than fiscal year 

2008 (up to 20 years). 

Because of these reporting period issues, the difference between the number of confirmed 

releases is also significantly different between the Colorado public record (7,016) and the FY08 

Corrective Action Measures (164). Because of this difference, the number of confirmed releases 

reported in Colorado’s public record was not included in this analysis. Several other states 

(Idaho, Indiana, Louisiana, Maryland, North Carolina, Ohio, and Tennessee) had significant 

differences between the number of confirmed releases on the two reports.

For the number of inspections conducted, there were also several significant differences between 

the public record and FY08 Corrective Action Measures values. The Commonwealth of 

Northern Mariana Islands, Idaho, Maine, and New York values differed by greater than 100 

percent, although Idaho’s difference is likely the result of a reporting period difference between 

the two reports. Differences for Colorado, Rhode Island, and the Virgin Islands were all around 

75 percent or greater. Once again, Colorado’s difference is likely a result of reporting period 

issues.

With the exception of Indiana, differences between the compliance rates in the public record and 

FY08 Corrective Action Measures were small for all states and territories included in this 

analysis. The Indiana public record reported a combined compliance rate of 93 percent, whereas 

the FY08 Corrective Action Measures report a combined compliance rate of 65 percent.

Results for Source and Cause Information (Appendices 2 through 9)

Results from combining all public record data indicate that the most prevalent sources of releases 

are tank (26.1 percent), unknown (21.0 percent), other (19.1 percent), piping (12.0 percent), and 
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dispenser (11.8 percent) (Table 2). Specific release cause and source data were not available in

the California, Commonwealth of Northern Mariana Islands, New Hampshire, and Virgin Islands

public records. Because of the reporting period issues, specific release and cause data from the 

Colorado public record were not included in this analysis.

Table 2: Total Release Source Results from Public Records

Release Source

Tank Piping Dispenser STP Delivery Problem Other Unknown

26.1% 12.0% 11.8% 0.9% 9.1% 19.1% 21.0%

Results from combining all public record data indicate that the most prevalent causes of releases 

are unknown (63.1 percent), corrosion (9.2 percent), and physical/mechanical damage (8.0

percent) (Table 3). When combined, spill (5.5 percent) and overfill (7.6 percent) are the causes 

for 13.2 percent of releases reported in the public records.

Table 3: Total Release Cause Results from Public Records

Release Cause

Spill Overfill Phys/Mech Damage Corrosion Install Problem Other Unknown

5.5% 7.6% 8.0% 9.2% 0.5% 6.0% 63.1%

The source-specific release cause percentages for all public records are presented in Table 4. Of 

known causes, most tank releases are caused by corrosion (25.8 percent); most piping, dispenser, 

and STP releases are caused by physical/mechanical damage (18.0, 13.6, and 41.0 percent, 

respectively); and most delivery problem releases are caused by spills (30.1 percent) or overfills 

(58.5 percent).

Table 4: Combined Total Source and Cause Results from Public Records

Source Percentage 

of Releases

Cause

Spill Overfill Phys/Mech

Damage

Corrosion Install 

Problem

Other Unknown

Tank 26.1% 0.0% 0.0% 9.6% 25.8% 0.3% 7.3% 57.1%

Piping 12.0% 3.9% 1.4% 18.0% 9.1% 1.9% 4.9% 60.9%

Dispenser 11.8% 10.7% 6.2% 13.6% 2.6% 0.9% 4.8% 61.2%

STP 0.9% 0.0% 9.8% 41.0% 4.9% 3.3% 21.3% 19.7%

Delivery 

Problem

9.1% 30.1% 58.5% 1.7% 1.1% 0.1% 2.2% 6.2%

Other 19.1% 3.5% 3.8% 4.4% 1.4% 0.2% 10.1% 76.6%