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United States Government Accountability Office: 
GAO: 

Report to Congressional Committees: 

September 2013: 

Cargo Tank Trucks: 

Improved Incident Data and Regulatory Analysis Would Better Inform 
Decisions about Safety Risks: 

GAO-13-721: 

GAO Highlights: 

Highlights of GAO-13-721, a report to congressional committees. 

Why GAO Did This Study: 

Cargo tank trucks deliver gasoline and other flammable liquids daily 
for consumer use. Trucks are loaded and unloaded through external 
bottom lines that, after loading, may contain up to 50 gallons of 
liquid and are known as “wetlines.” Concerns have been raised about 
the safety of wetlines, since a collision may rupture them, releasing 
flammable liquid and possibly causing fatalities and property damage. 
PHMSA is responsible for regulating the safe transportation of 
hazardous materials and has proposed rules prohibiting the transport 
of flammable liquids in wetlines. 

In 2012, The Moving Ahead for Progress in the 21st Century Act 
required GAO to examine this issue. This report discusses (1) the 
extent that PHMSA’s data reliably identify wetline safety risks, (2) 
options for addressing wetline safety risks, and (3) how well PHMSA 
has assessed the costs and benefits of addressing these risks through 
regulation. GAO analyzed PHMSA’s wetline incident data for 1999 to 
2011, reviewed PHMSA’s regulatory cost-benefit analyses, and 
interviewed agency officials and industry and safety stakeholders. 

What GAO Found: 

The Department of Transportation’s (DOT) Pipeline and Hazardous 
Materials Safety Administration’s (PHMSA) incident data cannot be used 
to reliably identify risks from incidents involving collisions with 
and spills from tank trucks’ bottom lines (“wetlines”) because the 
incidents are not specifically identified in PHMSA’s database and the 
data contain inaccuracies. PHMSA requires carriers to report hazardous 
material incidents, but the reporting form does not specifically 
capture wetline incidents. PHMSA officials identify wetline incidents 
through a resource-intensive process of reviewing carrier-reported 
incident narratives and other information. However, GAO found that the 
narratives do not always clearly indicate whether an incident is 
wetline related and that information about the consequences of 
incidents, including fatalities, is not always accurate. PHMSA has 
made efforts to improve its data, such as adding quality checks, but 
this has not affected how wetline incidents are reported, and 
inaccuracies remain. 

One technology to purge liquid from wetlines exists, but use of this 
system is limited, and industry and safety stakeholders expressed 
concerns about it, such as concerns about the safety of retrofitting 
existing trucks with the device and its cost. Although other options 
have been proposed to address wetline risks, none has been pursued, 
and there are concerns about their safety and feasibility as well. For 
example, wetlines could be drained at loading terminals, but this 
creates issues over storing the drained fuel and whether it could be 
resold. 

PHMSA analyzed the costs and benefits of its proposed 2011 rule to 
prohibit transportation of flammable liquids in unprotected wetlines, 
but did not account for uncertainties in its analytical assumptions 
and limitations in the underlying incident data. For example, PHMSA’s 
analysis overstated the number of fatalities the proposed rule would 
prevent when considering actual past incidents. Furthermore, PHMSA 
based its cost analysis on the assumption that carriers would install 
a certain type of wetline purging system, but its limited adoption 
makes that cost uncertain. Federal guidance recommends that agencies 
account for uncertainty in regulatory analysis, such as limitations in 
PHMSA’s data and uncertainty in its assumptions. Without having done 
so, PHMSA’s analysis may not accurately represent the costs and 
benefits of its proposed rule. 

Figure: Examples of Wetline Incidents: 

[Refer to PDF for image: 2 illustrations] 

Minor incident scenario: 
Truck hits barrier pole at gas station. One of the wetlines is damaged 
resulting in a small spill. 

Severe incident scenario: 
A passenger vehicle goes through a stop sign and underruns a tank 
truck. One or more of the truck’s wetlines are sheared off, resulting 
in a larger gasoline spill and a fire. 

Source: GAO. 

[End of figure] 

What GAO Recommends: 

DOT should improve its wetline incident data by requiring carriers to 
specifically report wetline incidents and by improving its information 
on incident consequences. DOT should also address uncertainty in the 
assumptions and data underlying its regulatory cost-benefit analysis. 
DOT did not agree or disagree with the recommendations, but provided 
technical comments. 

View [hyperlink, http://www.gao.gov/products/GAO-13-721]. For more 
information, contact Susan A. Fleming at (202) 512-2834 or 
flemings@gao.gov. 

[End of section] 

Contents: 

Letter: 

Background: 

PHMSA's Incident Data Cannot Be Used to Reliably Identify Wetline 
Incidents, Although Efforts to Improve Data Quality Have Been 
Implemented: 

Stakeholders Identified Existing and Potential Options to Address 
Wetline Risks, but Have Concerns about Safety, Costs, and 
Implementation: 

PHMSA Analyzed Costs and Benefits for a Proposed Wetlines Rule, but 
Uncertainties Limit the Usefulness of the Analysis: 

Conclusions: 

Recommendations for Executive Action: 

Agency Comments: 

Appendix I: Objectives, Scope, and Methodology: 

Appendix II: PHMSA's Wetline Proposed-Rule Cost-Benefit Methodology 
and Related Changes: 

Appendix III: GAO Contact and Staff Acknowledgments: 

Tables: 

Table 1: Extent That Narratives on PHMSA-Identified Wetline Incidents 
Clearly Characterized Incidents as Wetline-Related, January 1999 
through March 2011: 

Table 2: Stakeholders' Views on Options to Address Wetline Risks: 

Table 3: Costs and Benefits Included in PHMSA's 2011 Cost-Benefit 
Analysis and Its 2012 Draft Revision: 

Table 4: Wetline Industry and Safety Stakeholders Interviewed: 

Table 5: Cost and Benefit Values and Calculation Methodologies from 
PHMSA's 2011 and 2012 Wetline Proposed-Rule Cost-Benefit Analyses: 

Figures: 

Figure 1: Cargo Tank Truck Components That Pertain to Loading, 
Transporting, and Unloading of Flammable Liquids: 

Figure 2: A Typical Process for Loading, Transporting, and Unloading 
Cargo Tank Trucks Carrying Flammable Liquids: 

Figure 3: Examples of Wetline Incidents: 

Figure 4: Timeline of Key Events and Federal Regulatory Actions on 
Wetlines: 

Figure 5: The Main Components of Cargo Tank Concepts' Automatic 
Wetline Purging System: 

Abbreviations: 

DOT: Department of Transportation: 

hazmat: hazardous material: 

MAP-21: Moving Ahead for Progress in the 21st Century Act: 

NTSB: National Transportation Safety Board: 

OMB: Office of Management and Budget: 

PHMSA: Pipeline and Hazardous Materials Safety Administration: 

[End of section] 

GAO:
United States Government Accountability Office: 
441 G St. N.W. 
Washington, DC 20548: 

September 11, 2013: 

The Honorable John D. Rockefeller, IV: 
Chairman: 
The Honorable John Thune: 
Ranking Member: 
Committee on Commerce, Science, and Transportation: 
United States Senate: 

The Honorable Bill Shuster: 
Chairman: 
The Honorable Nick J. Rahall, II: 
Ranking Member: 
Committee on Transportation and Infrastructure: 
House of Representatives: 

Americans rely on flammable liquids such as gasoline for daily 
personal and industrial use, but transporting these liquids poses 
inherent safety risks to people and property. Cargo tank trucks 
transporting flammable liquids in the United States are loaded and 
unloaded through external pipes under the tank compartments. These 
pipes, when they contain flammable liquid, are known as "wetlines" and 
can collectively carry up to 50 gallons of liquid per truck. The 
National Transportation Safety Board (NTSB), among others, has 
identified wetlines as a potential hazard because a broadside 
collision with a tank truck can rupture the wetlines, spilling 
flammable liquid and creating the potential to fuel fires and 
therefore increased damage and fatalities from such incidents. In 
1997, such an incident occurred in Yonkers, New York, when a passenger 
car collided with a tank truck under a highway overpass. The collision 
ruptured the truck's wetlines, resulting in a passenger fatality and 
the destruction of the overpass. The incident, cleanup, and subsequent 
infrastructure repairs created significant and costly traffic delays 
in the region.

In 1998, after investigating the Yonkers incident, NTSB recommended 
that the Department of Transportation (DOT) prohibit transportation of 
all hazardous materials in wetlines. DOT subsequently proposed rules 
to prohibit the transportation of flammable liquids in unprotected 
external product piping ("wetlines"), but did not adopt final rules in 
those proceedings. In January 2011, the Pipeline and Hazardous 
Materials Safety Administration (PHMSA), an operating administration 
of DOT, again proposed a rule to prohibit the transportation of 
flammable liquids in unprotected wetlines and released an initial 
analysis of the proposed rule's costs and benefits. PHMSA updated its 
cost-benefit analysis in March 2012, but did not release this version 
publicly. The Moving Ahead for Progress in the 21st Century Act (MAP-
21), enacted in July 2012, temporarily stopped PHMSA from issuing a 
final wetlines rule except in very specific circumstances[Footnote 1] 
and required us to examine the risks of and alternatives to 
transporting flammable liquids in wetlines. In this report we discuss: 
(1) the extent that PHMSA's data can be used to reliably identify 
wetline safety risks, (2) options for addressing wetline safety risks, 
and (3) how well PHMSA has assessed the costs and benefits of 
addressing these risks through regulation.

To evaluate the extent that PHMSA's data can be used to reliably 
identify wetline safety risks, we examined PHMSA's process for 
identifying wetline incidents among its reported hazardous materials 
(hazmat) incidents, analyzed how useful PHMSA's incident data from 
January 1999 through March 2011 are for identifying such incidents, 
[Footnote 2] and examined whether these data accurately captured 
information about the incidents' consequences. We reviewed the 
reliability of these data by examining them for missing data and 
inconsistencies, reviewing PHMSA's process for obtaining wetline 
incident data and maintaining them in the agency's incident database, 
and reviewing the agency's related internal controls. We concluded 
that the data were sufficiently reliable for the purposes of our 
report. To describe options for addressing wetline safety risks, we 
identified options by reviewing documents filed in the current and 
prior PHMSA wetline safety rulemakings and interviewing petroleum and 
related transportation industry and safety stakeholders (see appendix 
I for a list of stakeholders we interviewed). We also asked 
stakeholders about their views on the advantages and disadvantages of 
these options and reviewed comments filed in the most recent PHMSA 
wetline rulemaking. We placed particular focus on examining the 
wetline purging system, because it is the option used in PHMSA's 
wetlines rulemaking analysis and the only option we identified that 
has been installed to address wetline risks. To evaluate how well 
PHMSA has assessed the costs and benefits of its January 2011 proposed 
wetline rule, we reviewed PHMSA's associated regulatory cost-benefit 
analysis, examined the reliability of PHMSA's supporting wetline 
incident data used to inform the analysis, and interviewed PHMSA 
officials about their efforts. See appendix I for a more detailed 
description of our objectives, scope and methodology.

We conducted this performance audit from September 2012 to September 
2013 in accordance with generally accepted government auditing 
standards. Those standards require that we plan and perform the audit 
to obtain sufficient, appropriate evidence to provide a reasonable 
basis for our findings and conclusions based on our audit objectives. 
We believe that the evidence obtained provides a reasonable basis for 
our findings and conclusions based on our audit objectives.

Background: 

Flammable Liquid Distribution: 

Every day, tens of thousands of cargo tank trucks transport hazardous 
materials classified as flammable liquids (primarily gasoline and fuel 
oil) for sale in the United States.[Footnote 3] This involves some 
safety risk because of the volatile nature of flammable liquids, the 
volume of liquid transported (up to 9,200 gallons per truck), and the 
numbers of trucks and passenger vehicles on the road. Tank trucks that 
carry flammable liquids have three main components--the truck, the 
trailer, and the cargo tank. The tank may be divided into several 
compartments--usually four or five--allowing the truck to carry 
different petroleum products in a single trip, such as different 
grades of gasoline and diesel fuel. Although the design of cargo tank 
trucks can vary depending on the model and manufacturer, the 
components in figure 1 are common features.

Figure 1: Cargo Tank Truck Components That Pertain to Loading, 
Transporting, and Unloading of Flammable Liquids: 

[Refer to PDF for image: illustration] 

Cargo tank: 
Storage compartments. 

Manhole cover: 
Located on top of cargo tanks, manhole covers contain an overfill 
sensor and components for vapor recovery. In the 1980s, the petroleum 
industry began to move away from top loading flammable liquids through 
manhole covers. 

Loading valves (As seen from the other side of the cargo tank truck): 
Facilitate connection between bottom lines and fuel terminal loading 
rack. 

Bottom lines: 
Used for loading and unloading flammable liquids. When containing 
flammable liquid, bottom lines are known as wetlines. The point at 
which the bottom lines connect to the tank is designed to shear off in 
the event of a collision to protect the tank from further damage. The 
length of each bottom line depends on the number of compartments and 
the configuration of the tanks. 

Source: GAO and photos from National Tank Truck Carriers. 

[A] Weight restrictions limit a cargo tank truck's operating capacity 
to between 7,500 and 9,200 gallons of liquid, which is usually less 
than the tank's total capacity. 

[End of figure] 

The rule proposed by PHMSA in January 2011 would require that 
flammable liquids be eliminated from bottom loading and unloading 
lines, such as by purging the bottom lines of product, or that bottom 
lines be protected with approved bottom protection devices.[Footnote 
4] The rule would apply to cargo tank trucks that typically transport 
gasoline, diesel, and fuel oil from distribution terminals--of which 
there are nearly 400 nationwide--to retail outlets or gas stations 
(see figure 2).

Figure 2: A Typical Process for Loading, Transporting, and Unloading 
Cargo Tank Trucks Carrying Flammable Liquids: 

[Refer to PDF for image: illustration] 

Step 1: 
The cargo tank truck’s driver enters the fuel terminal, pulls into a 
lane, and parks at loading rack. 

Step 2: 
At the fuel terminal, the driver raises the brake bar and connects the 
loading arms to the truck’s loading valves. The driver also connects 
the truck’s vapor recovery system to the rack. When the driver 
finishes loading the cargo tank truck’s compartments, the driver 
disconnects the loading arms and the vapor recovery connection and 
drops the brake bar.[A] At this point the bottom lines are full of 
liquid and considered wetlines. 

Step 3: 
The driver leaves the terminal and drives to the delivery point. On 
the road, collisions between cargo tank trucks and vehicles or 
stationary objects, such as lamp posts, can occur. 

Step 4: 
The driver arrives at a delivery point, such as a gas station. Lifting 
the brake bar, the driver hooks the cargo tank’s bottom lines up to 
the underground tank(s). The driver releases the internal valve(s) and 
begins to unload the compartment(s). When unloading is complete, the 
driver disconnects the lines and lowers the bar. Typically a driver 
unloads an entire compartment, including that compartment’s bottom 
line. Some residual liquid and vapor may remain in the lines, but the 
bottom line associated with the unloaded compartment(s) is no longer a 
wetline. At the delivery point, collisions between the cargo tank 
truck and stationary objects can occur. 

Step 5: 
The driver leaves the delivery point and either drives to the next 
delivery point or returns to a terminal to reload the cargo tank. 

Source: GAO. 

[A] The brake bar interlock is a system that, when activated, applies 
the truck's parking brakes. A driver lifts the brake bar to access the 
truck's loading valves, immobilizing the truck during loading or 
unloading. 

[End of figure] 

In the 1980s, to address volatile organic compound emission reduction 
requirements,[Footnote 5] as well as worker safety issues, the 
petroleum industry changed cargo tank-loading procedures from loading 
through the manhole covers on the top of the truck to loading through 
the bottom lines. Prior to this change, the bottom lines were used for 
unloading only and therefore generally did not contain more than a 
residual amount of flammable liquids during transport. In using bottom 
lines for loading, because the lines are at the lowest point on the 
truck, they do not drain into the main tanks but contain fuel. Bottom 
lines containing fuel are referred to as "wetlines." 

Wetline Incidents and Reporting: 

Wetline incidents result from collisions involving tank trucks that 
lead to the release of flammable liquid from wetlines. Such incidents 
range from easily contained spills to catastrophic situations. 
Carriers that transport hazardous materials, including flammable 
liquids like gasoline, are required to report incidents involving the 
release of hazmat to PHMSA.[Footnote 6] Carriers, for example, must 
submit an electronic or paper incident reporting form within 30 days 
of the incident. This form is designed to provide information about 
the vehicle and container involved in the incident, the component of 
the container that failed, the type and quantity of product released, 
and, if applicable, fatalities, injuries, and the dollar value of 
significant damages associated with the incidents.[Footnote 7] The 
form also includes a space for carriers to write a descriptive 
narrative of the incident. Information from these forms appears in 
PHMSA's publicly available web-based incident database.[Footnote 8] 
According to PHMSA, it uses the database for its safety oversight 
work, including regulatory efforts.

While most wetline incidents identified by PHMSA did not result in 
fires, spilled flammable liquid can ignite and create the potential 
for fatalities as well as increased property and environmental 
damages. Incidents may be the result of a tank truck striking a 
stationary object or a moving passenger vehicle striking the tank 
truck. Figure 3 shows examples of two types of wetline incidents.

Figure 3: Examples of Wetline Incidents: 

[Refer to PDF for image: 6 illustrations] 

Minor incident scenario: 

Truck hits barrier pole at gas station. 

Potential consequences: 
One of the bottom lines is damaged resulting in a small spill. 

Potential response required: 
Driver cleans up the spill with a kit including gloves, goggles, and 
absorbent materials. Driver may also call emergency services to 
inspect the scene for safety. 

Severe incident scenario: 

A passenger vehicle goes through a stop sign and underruns a tanker 
truck. 

Potential consequences: 
One or more of the bottom lines of the cargo tank truck could be 
sheared off. As a result, up to 50 gallons of gasoline could spill and 
ignite a fire. 

Potential response required: 
* Fire department; 
* Police department; 
* Hazmat cleanup; 
* Emergency medical assistance. 

Source: GAO. 

[End of figure]

DOT Wetline Initiatives, 1989-2012: 

PHMSA is responsible for regulating the safe and secure transportation 
of hazardous materials to reduce the risks to people and the 
environment. In 1989 and 1990, PHMSA's predecessor, the Research and 
Special Programs Administration, promulgated final rules that 
prohibited external product piping, such as bottom lines, from 
retaining hazardous liquids unless the cargo tank truck is equipped 
with bottom damage protection devices.[Footnote 9] Citing concerns 
about the potential costs of modifying fuel terminal operations, the 
lack of data on incidents, and the lack of information on possible 
alternatives to empty wetlines after bottom loading, the Research and 
Special Programs Administration exempted tanks transporting gasoline 
and other flammable liquids from the regulation.[Footnote 10] Thus, 
the resulting regulations, in general, pertain to certain poisonous 
liquids, oxidizer liquid, liquid organic peroxide, or corrosive 
liquids, but not to gasoline.[Footnote 11]

The 1997 Yonkers incident drew attention to the safety risks of 
wetlines because it involved a fatality as well as unusually high 
damages. Specifically, its destruction of a highway overpass resulted 
in severe property damage, and the incident's location in a congested 
area led to severe economic costs. Following NTSB's recommendation 
that DOT prohibit transport of hazardous materials in wetlines, 
[Footnote 12] DOT (through the Research and Special Programs 
Administration and later PHMSA) submitted a draft proposed rule to the 
Office of Management and Budget (OMB) to address the issue in 2000 and 
later issued a proposed rule in 2004. PHMSA withdrew its 2004 proposed 
rulemaking in 2006 because it concluded that the benefits of the rule 
would not justify the costs.[Footnote 13] PHMSA proposed another 
wetline rule in 2011. Figure 4 shows the timeline of key events and 
major regulatory efforts to address wetline risks.

Figure 4: Timeline of Key Events and Federal Regulatory Actions on 
Wetlines: 

[Refer to PDF for image: time line] 

1989: 
DOT prohibits transporting certain hazmat liquids in unprotected 
wetlines and exempts gasoline from such prohibition. 

1997: 
A Yonkers, NY wetline incident results in one fatality and unusually 
severe infrastructure and economic impacts. 

1998: 
NTSB recommends DOT prohibit transporting of all hazardous materials 
liquids in wetlines and does not include any exemptions. 

2000-2001: 
DOT submits a proposed rule to prohibit wetlines to the Office of 
Management and Budget (OMB), which OMB returns for reconsideration due 
to concerns with DOT’s methodology for determining costs and benefits. 

2004-2006: 
DOT issues a revised proposed rule but ultimately concludes such a 
rule would not be cost beneficial and withdraws it. PHMSA works with 
industry and emergency responders to produce a pamphlet to raise 
awareness among responders about wetlines. 

2011: 
PHMSA reopens its wetlines rulemaking with a new proposed rule and 
cost-benefit analysis. 

2012: 
MAP-21 temporarily prohibits DOT from issuing a final rule on wetlines 
pending the completion of a GAO study.[A] 

Source: GAO. 

[A] Section 33015 of MAP-21 prohibits DOT from issuing a wetlines 
final rule prior to either the completion of GAO's mandated study or 
until July 2014, whichever is earlier, unless DOT determines that a 
risk to public safety, property, or the environment is present or an 
imminent hazard exists and that the regulations will address the risk 
or hazard. 

[End of figure] 

PHMSA's Incident Data Cannot Be Used to Reliably Identify Wetline 
Incidents, Although Efforts to Improve Data Quality Have Been 
Implemented: 

PHMSA's incident data do not reliably capture the risks and 
consequences of wetline incidents because these incidents are not 
specifically identified in its database, and PHMSA's incident data 
also contain inaccuracies. Although PHMSA requires reporting of hazmat 
incidents through incident reporting forms, it does not require 
carriers to explicitly state on the form whether the incident is 
wetline-related. Consequently, to identify wetline incidents, PHMSA 
officials must review carrier-reported narratives and other 
information, a review that is resource-intensive. Moreover, this 
review may not result in an accurate accounting of the number and 
consequences of wetline incidents because the information does not 
always clearly indicate whether the incident is wetline-related and 
because of inaccuracies and omissions in the data. PHMSA has made 
efforts to improve its data, such as implementing quality checks, but 
this does not affect how wetline incidents are reported, and errors 
remain. This limits the usefulness of these data as supporting 
information for PHMSA's wetline regulatory analysis.

Limitations with PHMSA's Incident Data Make It Difficult to Identify 
Wetline Incidents: 

PHMSA's hazmat incident database does not specifically code incidents 
as wetline-related because its incident reporting form does not 
require carriers to explicitly report whether an incident is wetline-
related. Consequently, it is not possible to retrieve a list of 
wetline incidents through PHMSA's database. To identify wetline 
incidents, PHMSA staff must analyze incident narratives and other 
carrier-reported information for characteristics that are indicative 
of wetline incidents.[Footnote 14] This makes identifying these 
incidents resource-intensive and somewhat subjective, since the 
determination of which incidents are wetline-related is not always 
based on complete information, as incident data may be unclear or 
missing. OMB guidance states that agencies should develop a process 
for reviewing information quality as part of information resources 
management, including when collecting and maintaining the information 
to be used for regulatory analysis, which is one of PHMSA's uses for 
its incident data.

Wetline Incident Identification: 

Annually, PHMSA receives reports of about 15,000 to 20,000 hazmat 
incidents, and the percentage of these incidents that PHMSA identified 
as wetline-related is relatively small. To support PHMSA's 2011 cost-
benefit analysis, PHMSA officials said that a team spent months 
reviewing incident data to identify wetline incidents and, as of 
January 2011, identified 172 wetline incidents occurring over the 10-
year period from January 1999 through December 2008.[Footnote 15] 
These incidents were used in the January 2011 proposed rule and 
related cost-benefit analysis. According to PHMSA's updated March 2012 
draft cost-benefit analysis, after commenters in the wetline 
rulemaking docket questioned whether some of these incidents should 
have been identified as wetline incidents, PHMSA reexamined the 172 
incidents it originally identified and updated the analysis to include 
incidents through March 2011. This led PHMSA to a provisional figure 
of 132 wetline incidents, which PHMSA used in its updated 2012 draft 
cost-benefit analysis.[Footnote 16] Because PHMSA has not issued a 
final rule on this subject, information in either the 2011 or draft 
2012 analysis is subject to change.

To identify wetline incidents for both the 2011 and 2012 reviews, 
PHMSA officials said they conducted a broad search of cargo tank truck 
incidents in the database and then reviewed incident reports' 
narrative descriptions. If a description was insufficient to make a 
determination, officials reviewed the content of other fields in the 
incident's database entry such as component failure information, 
packaging identification, the amount and type of hazardous material 
released, and location of the vehicle at the time of the accident. 
PHMSA officials said their incident database provided sufficient 
information about incidents to make a judgment about each incident. 
However, the amount of time, staff, and specialized knowledge required 
for this process was more extensive than if PHMSA required carriers to 
identify whether incidents are wetline-related on the incident 
reporting forms. Officials also stated that, since their method of 
identifying wetline incidents by reviewing narrative descriptions 
required substantial resources, the agency was not able to direct 
additional resources to follow up with carriers to clarify missing or 
unclear data as part of the review to identify wetline incidents, 
except in cases involving fatalities.

In identifying consequences of wetline incidents, PHMSA has little 
information besides what is provided by the carriers. Specifically, 
only one wetline incident that occurred during the 1999 to 2011 
incident study period was investigated by NTSB and PHMSA, and PHMSA 
officials said they were unaware of any other investigations of 
wetline incidents by federal, state, or local authorities during this 
period.[Footnote 17] Therefore, PHMSA's record of the consequences of 
wetline incidents is based almost solely on information provided by 
carriers without corroborating information from other sources. 
Additionally, information provided by carriers is not always clear. 
For example, PHMSA officials said that carriers may misidentify 
components or use colloquialisms in the narrative (such as "fill tube" 
or "drop tube") to denote bottom lines. Further, officials said that 
terminology used in the report could vary depending on whether the 
carrier's corporate safety officer, the driver, or an attorney fills 
out the form.

PHMSA officials stated that they considered a number of factors in 
identifying wetline incidents for the 2011 proposed rule, such as 
characteristics that could indicate an incident was wetline-related in 
the absence of more definitive information and exceptions included in 
the proposed rule that would exclude certain incidents. For example, 
PHMSA officials told us they considered any tank truck incident 
involving a collision or crash with a fire to be a wetline incident, 
regardless of the amount of released flammable liquid.[Footnote 18] 
The specific cause of incidents involving fires may be difficult to 
pinpoint, since the fire may destroy the forensic evidence needed to 
make that determination. Therefore, PHMSA officials assumed that 
incidents where the fire was not attributable to any one part of the 
vehicle were wetline-related because this approach would be less 
likely to exclude a severe incident that was caused by wetlines. 
However, this also means that the analysis could include severe 
incidents where the fire was the result of other factors, such as a 
puncture to the cargo tank. PHMSA officials stated that punctures to 
the cargo tank require forceful impact and are rare in incidents that 
do not involve a truck overturn. Therefore, in tank truck incidents 
with large spillages and fires, the fire likely began from the release 
of flammable liquid from bottom lines, according to PHMSA officials. 
Stakeholders disagree on whether this is a reasonable approach, with 
some supporting it because it can address potential underreporting of 
incidents with fires and others stating that the practice artificially 
magnifies the benefits of the proposed regulation by including 
incidents that would not be prevented by eliminating wetlines. 
[Footnote 19] In applying regulatory factors to the identification of 
wetline incidents, PHMSA excluded some incidents involving bottom line 
spillage due to exceptions in the proposed wetlines rule, such as 
incidents involving smaller trucks that the proposed rule would 
exclude from regulation.[Footnote 20]

In determining whether particular incidents were wetline-related, 
PHMSA did not clearly document its decision-making process. For 
example, in reviewing incidents that occurred from 2009 to 2011, PHMSA 
identified 13 incidents as "possibly" wetline-related from the 
incident narrative information and subsequently used other incident 
information in making a final determination that 7 of those incidents 
were wetline-related.[Footnote 21] Although officials documented these 
incidents in a spreadsheet, they did not include details about the 
specific decision-making process PHMSA used to make a final 
determination for each incident. Therefore, it is not clear how the 
agency concluded that 7 of the 13 "possibly" wetline-related incidents 
were wetline-related and that the other 6 incidents were not.

Incident Data Limitations: 

Our review of the reported incident data and narratives confirmed that 
it is challenging to identify wetline incidents. Using incident data 
other than the narratives, we attempted to identify wetline incidents 
on the basis of common characteristics of such incidents--involving a 
cargo tank truck, a release of flammable liquid, bottom line failure, 
and spillages or fires. In doing so, we were unable to generate a list 
of incidents that approximated PHMSA's list of wetline incidents. 
Specifically, our search of the database turned up approximately 270 
incidents from January 1999 through March 2011 that PHMSA did not 
identify as wetline-related because they involved driver error or 
spills from areas other than wetlines, among other reasons.[Footnote 
22] Conversely, some PHMSA-identified wetline incidents did not show 
up in our search results for reasons such as that they were coded as 
involving portable tanks instead of cargo tanks, indicating probable 
carrier error in reporting the incident.[Footnote 23]

Additionally, inconsistencies with the component failure information 
in PHMSA's incident data limit the usefulness of this information for 
identifying wetline incidents. The incident reporting form has a field 
for carriers to report up to two components that were the most 
catastrophic failure points in the incident, such as reporting failure 
of the bottom lines.[Footnote 24] PHMSA officials told us that 
although reporting this information is not optional, carriers 
sometimes leave this field blank, and the electronic version of the 
form lacks controls to force the entry of data in this field. 
Furthermore, carriers sometimes provide inaccurate information. For 
example, among the 132 incidents PHMSA identified as wetline-related, 
99 of the database entries for those incidents either did not list a 
code indicating bottom-line failure or had blank codes.[Footnote 25] 
PHMSA's guidance for filling out the incident reporting form includes 
a list of possible failure codes, but does not provide definitions of 
the codes. PHMSA officials said they do not have much confidence in 
using the failed components information for identifying wetline 
incidents. PHMSA officials acknowledged that missing data make it 
difficult to analyze incidents, but also said that the agency does not 
follow up with the carrier in these cases to confirm or correct the 
information unless the incident involves fatalities or 
injuries.[Footnote 26]

Unclear Incident Narratives: 

Our review of the narratives for the 132 PHMSA-identified wetline 
incidents revealed that almost one-third of the narratives did not 
clearly identify the incidents as wetline-related because they lacked 
sufficient detail about the incident, used inconsistent terminology, 
or were blank. For example, some narratives indicated damage to other 
components that could have been the source of the spill. Other 
narratives did not indicate a collision resulting in a flammable 
liquid release. We also found instances of inconsistency in the 
database, such as narrative descriptions that did not corroborate 
other information provided in the database entry.[Footnote 27] Table 1 
shows the extent to which we were able to identify wetline incidents 
from the narratives.

Table 1: Extent That Narratives on PHMSA-Identified Wetline Incidents 
Clearly Characterized Incidents as Wetline-Related, January 1999 
through March 2011: 

Extent that incidents were clearly wetline-related[A]: Clearly wetline-
related; 
Number of incidents: 93; 
Examples of incident descriptions[B]: 
* Bottom lines were impacted by a collision, causing a spill. The 
compartment above the line was not affected; 
* Bottom lines hit a post or pole at a gas station, causing a small 
release; 
* A passenger vehicle ran a red light and struck a trailer at the 
valves of the bottom lines, damaging the lines and resulting in a 
release and immediate fire. 

Extent that incidents were clearly wetline-related[A]: Unclear if 
wetline-related; 
Number of incidents: 38; 
Examples of incident descriptions[B]: 
* The bottom line or internal valve leaked; 
* Bottom lines were damaged and minor tank damage also occurred; 
* A trailer struck an unattended vehicle; 
* A truck rolled over and gasoline spilled from the damaged trailer; 
* More than 50 gallons of liquid--the amount that would typically be 
in wetlines--were released from a tank truck after a collision; 
* Pipes froze and broke. 

Extent that incidents were clearly wetline-related[A]: No narrative 
provided; 
Number of incidents: 1. 

Extent that incidents were clearly wetline-related[A]: Total; 
Number of incidents: 132. 

Source: GAO Analysis of PHMSA incident data.

[A] We assigned incidents to each category based on decision rules 
using PHMSA's definition of a wetline incident.

[B] Descriptions are paraphrased from actual incident narratives 
because carriers tended to use jargon and shorthand when describing 
the incidents. 

[End of table] 

Problems with PHMSA's Incident Data Limit Their Reliability for 
Regulatory Analysis, Even Though Improvement Efforts Have Been Taken: 

In addition to the limitations in identifying the number of incidents, 
we also found PHMSA's incident data inaccurately portray the 
consequences of wetline incidents, thus limiting their reliability for 
regulatory analysis. Internal control standards for federal executive 
branch agencies require that agencies have relevant, reliable, and 
timely information for decision-making and external reporting 
purposes.[Footnote 28] OMB also has data quality guidelines for 
regulatory purposes.[Footnote 29] Because much of the economic benefit 
of the proposed wetline regulation would be the avoided fatalities and 
damages from wetline incidents, inaccuracies in these data raise 
concerns about their reliability for accurately quantifying some 
benefits of the proposed rule. Specifically, we found problems with 
incident data related to fatalities and damages: 

* Fatality Data. Among the 132 wetline incidents identified by PHMSA 
since 1999, there are 7 that PHMSA's incident data show had one or 
more fatalities, with a total of 11 fatalities.[Footnote 30] However, 
the fatalities in 3 of the 7 incidents were misclassified as to 
whether they were caused by a hazmat release and thus preventable by 
the elimination of wetlines. According to PHMSA's incident-reporting 
guidance, hazmat-related deaths are directly attributed to the release 
of hazmat, such as a fatality caused by a fire resulting from the 
release of gasoline from wetlines. Nonhazmat-related deaths could 
occur in a hazmat incident but are attributed to other causes, such as 
internal injuries resulting from blunt force trauma during a 
collision. This distinction can have significant implications for the 
proposed rule's cost-benefit analysis. Since the avoidance of hazmat-
related deaths is a major portion of the rule's calculated benefit, 
nonhazmat-related deaths are not included in the calculation as they 
would not be prevented by the rule. We found that fatalities in 2 of 
the 4 incidents recorded in PHMSA's database as hazmat-related were 
actually nonhazmat-related according to documentation about the 
incidents, which we confirmed with PHMSA officials.[Footnote 31] 
Conversely, the fatality in 1 of the 3 incidents with fatalities 
recorded as nonhazmat-related was later determined to be hazmat-
related.[Footnote 32]

* Other Damage Data. Information on the dollar value of incident 
damages was sometimes missing or potentially inaccurate, since costs 
reported as "$0" in the database may represent no cost or an 
unreported cost.[Footnote 33] PHMSA officials stated they have not 
always followed-up with carriers to obtain missing cost information 
and that carriers do not always have full cost information. 
Specifically, costs not incurred directly by carriers like response 
and cleanup costs may not be known to the carrier at the time of 
submitting the form.[Footnote 34] Further, incidents with minor costs 
might not reflect any costs because carriers are not required to 
report total costs of $500 or less; however, in such cases, the data 
do not indicate whether a cost of $0 indicates an actual "no cost" 
that would not have to be reported or a greater cost that was 
unreported. Although carriers are expected to contact PHMSA with 
significant updates to cost estimates up to a year after reporting, 
officials stated that carriers often do not.

Concerns have been previously raised about the quality of PHMSA's 
incident data, including its usefulness for identifying wetline 
incidents. In a 2009 report on its data, PHMSA acknowledged the 
limitation that its wetline data analysis depends on reviewing 
narrative descriptions provided by carriers in reporting forms because 
wetline incidents are not specifically coded in the data.[Footnote 35] 
Also that year, senior PHMSA officials' congressional testimony stated 
that identifying wetline incidents is staff-intensive and requires 
detailed analysis of database entries.[Footnote 36] More recently, a 
2013 National Academies Transportation Research Board report sponsored 
by PHMSA stated that detailed data on the nature of damages in 
incidents involving the release of hazardous materials are necessary 
for studying the performance of the container transporting the 
product. The report stated that while PHMSA's database collects some 
of this information, it is not sufficiently detailed.[Footnote 37]

To address concerns about its data, PHMSA has made data process 
changes intended to improve the accuracy and completeness of its 
incident database. For example, PHMSA officials said that in 2012 the 
agency initiated a thorough review and follow-up audits of all 
incidents that result in deaths or injuries, which they said increases 
the likelihood of identifying wetline incidents. However, these 
changes do not address that wetline incidents are not specifically 
identified through the incident reporting process and do not apply to 
the inaccuracies in older incident data. Some of the steps PHMSA has 
taken according to officials included the following: [Footnote 38]

* In 2005, PHMSA updated its incident reporting form and process by, 
among other things, providing more specific options for identifying 
the part of the vehicle that failed and requiring carriers to submit 
report updates up to 1 year after an incident when information about 
incident fatalities or significant damages changes.

* Also in 2005, PHMSA implemented an electronic reporting option that 
incorporates checks to improve completeness before the form is 
approved in the database.[Footnote 39]

* Since about 2 years ago, PHMSA has provided training and outreach to 
carriers on filling out the incident form more accurately and 
completely and to encourage online reporting.

* The agency implemented an improved data quality process starting in 
2009, including updating its incident database to correct information 
it determined to be inaccurate. Before that time, the agency generally 
did not make changes to carrier-reported information in the system. 
Specifically, PHMSA reviews submitted incident reporting forms for 
accuracy and completeness and conducts follow-up with carriers to 
resolve missing information in the database.[Footnote 40]

* To address concerns about under-reporting of incidents, PHMSA 
attempts to discover potentially reportable incidents by reviewing 
incident reports submitted to the National Response Center and 
monitoring the news media.[Footnote 41] PHMSA tracks severe incidents 
that may need reporting by carriers and, if warranted, may contact the 
carrier to request submittal of a reporting form, a process that has 
identified some wetline incidents, according to PHMSA officials.

* In an effort to improve the accuracy of its fatality and injury 
data, PHMSA developed a worksheet to better track and confirm 
information about fatalities and injuries.[Footnote 42] In 2012, PHMSA 
began working with the Federal Motor Carriers Safety Administration to 
investigate hazmat incidents involving fatalities, injuries, and 
fires. Also in 2012, PHMSA began retaining coroner's or medical 
examiner's reports associated with each fatality.[Footnote 43]

Although these efforts could improve PHMSA's incident data going 
forward, they have no effect on some of PHMSA's older wetline incident 
data. The agency relied on data back to 1999 in analyzing costs and 
benefits of its proposed wetline rule. As previously discussed, upon 
reexamination of its data, PHMSA changed the number of wetline 
incidents supporting its current proposed rule. However, because of 
the subjective nature of how wetline incidents are identified, the 
possibility still exists that PHMSA's identification of some incidents 
as wetline-related may be inaccurate. Industry stakeholders told us 
they believe PHMSA's data overstate the prevalence of wetline 
incidents and that their low number does not justify regulation. 
Conversely, some safety stakeholders said such incidents may be 
underreported. Additionally, as we have mentioned earlier, we found 
inaccuracies in these data, limiting their reliability for accurately 
quantifying the consequences of wetline incidents. In particular, 
flaws with the fatality and damages data have the potential to skew 
calculations of the rule's benefit of avoiding wetline-related 
fatalities. This calls into question whether these data are 
sufficiently reliable to support regulatory analysis unless PHMSA 
makes adjustments for the potential uncertainty in the analysis. 
Without accurate data on the number and consequences of wetline 
incidents, the consequences of wetline incidents remain unclear and 
the benefits of wetlines regulation may not be accurately calculated 
in PHMSA's regulatory analysis.

Stakeholders Identified Existing and Potential Options to Address 
Wetline Risks, but Have Concerns about Safety, Costs, and 
Implementation: 

An Existing Purging System to Address Wetline Safety Risks Is in 
Limited Use: 

A purging system is a device a carrier or manufacturer can install on 
a cargo tank truck that removes liquid from the truck's bottom lines 
after a driver finishes loading the cargo tanks at the fuel terminal. 
One company, Cargo Tank Concepts, manufactures a purging system that 
uses compressed air from an auxiliary tank to push the liquid in the 
bottom lines through small ancillary lines and into the cargo 
compartments (see figure 5). When the purge is complete, the lines 
retain only residual amounts of liquid and vapor.

Figure 5: The Main Components of Cargo Tank Concepts' Automatic 
Wetline Purging System: 

[Refer to PDF for image: illustration] 

The purging system control box is alerted by an optical sensor when 
liquid needs to be purged from the bottom line. With the internal 
valve and loading valve closed, compressed air is introduced into the 
bottom line, which displaces the liquid out through the ancillary 
purging line, a one-way check valve, and back into the tank truck 
compartment. 

Depicted in the illustration: 
Tank truck compartment (filled with flammable liquid); 
Internal valve (closed); 
One-way “check” valve; 
Compressed air; 
Purging system control box; 
Ancillary purging line; 
Optical sensor; 
Bottom line; 
Loading valve (closed). 

Source: GAO analysis and observance of Cargo Tank Concepts’ technology. 

[End of figure]

Cargo Tank Concepts designed two versions of the purging system: 
automatic and manual. With the automatic system, after the driver 
finishes loading the cargo tank, electronic sensors detect liquid in 
the bottom lines and the system automatically begins to purge. One 
major petroleum company installed the automatic purging system on its 
cargo tank truck fleet starting in the late 1990s.[Footnote 44] Cargo 
Tank Concepts has also equipped a few trucks owned by other carriers 
with the automatic version to demonstrate the purging system. The 
manual system engages when the driver pushes a button to activate the 
purge, typically after loading the cargo tank. According to the 
purging system manufacturer, as of June 2013, there were no manual 
purging systems in use.[Footnote 45] PHMSA officials, three industry 
stakeholders, and two safety stakeholders told us that they anticipate 
other purging solutions would be developed if PHMSA's proposed 
wetlines rule were to go into effect.[Footnote 46] We contacted two 
other manufacturers that an industry publication reported were 
developing wetline purging systems. Both companies told us they have 
not produced any systems other than prototypes; however, both said 
they could move forward with development, and eventually production, 
if PHMSA finalizes a wetlines rule.

Industry associations and companies, manufacturers, repair shops, 
federal agencies, and safety groups identified advantages and 
disadvantages of using a purging system to address wetline risks. Due 
to limited use, most stakeholders do not have first-hand experience 
with the wetline purging system and its performance. Thus, 
stakeholders' familiarity with the more technical aspects of the 
system varied and some stakeholders, particularly safety groups, 
declined to comment. However, based on their expertise with cargo tank 
trucks and transporting flammable liquids, stakeholders provided views 
on using such a system in that operating environment.

According to stakeholders, the advantages of using a purging system 
include: 

* Addressing wetline safety risks: Purging removes all but a residual 
amount of liquid from the bottom lines, in accordance with one of the 
ways to meet the standard in PHMSA's proposed rule. Removing flammable 
liquid from the bottom lines may reduce fatalities and the number and 
severity of injuries in the event of a broad-side collision between a 
passenger vehicle and a cargo tank truck. The absence of liquid in the 
bottom lines may also reduce property and environmental damages 
associated with hazardous materials spilling from the bottom lines.

* Identifying faulty valves: Depending on the design of a purging 
system, it may permit detection of faulty internal emergency valves. 
If an emergency valve is not working properly, liquid may leak from a 
cargo tank compartment into the bottom lines. In the event of a 
collision with wetlines, a faulty emergency valve could cause a 
carrier to lose liquid from an entire cargo tank compartment. If a 
purging system attempts to purge liquid when the line should be clear, 
a driver may be alerted that there is a problem; if the driver were 
not alerted, the faulty valve could go undetected until the next 
inspection.

Stakeholders also raised a number of concerns about purging systems, 
but disagreed about the significance of them: 

* Retrofitting: Industry stakeholders are concerned about the safety 
of installing purging systems on in-service tank trucks due to the 
risk that welding on the tanks--if not completely free of gasoline 
vapor--creates a risk of explosion. Specifically, 9 industry 
stakeholders and 3 safety groups we interviewed raised this issue, and 
18 of the 21 of the industry associations and companies providing 
comment in response to PHMSA's 2011 proposed wetlines rule reinforced 
those concerns as being a risk if the proposed regulation required 
retrofitting.[Footnote 47] However, stakeholders also acknowledged 
that there are procedures that allow welding to be done safely, and 
repair shops routinely weld on cargo tanks when they require repair. 
Cargo Tank Concepts did not characterize the concern about 
retrofitting as significant, but the company has developed a 
"nonwelded" alternative to address industry concerns, which it has 
installed on one truck. However, three industry stakeholders expressed 
concern about the durability of such an installation, two of whom 
added that the "nonwelded" alternative would still entail "hotwork" 
such as cutting into the tank.[Footnote 48] According to Cargo Tank 
Concepts, the nonwelded installation involves drilling but not 
cutting, welding or other types of "hotwork." 

* Installation time: Stakeholders' estimates on the amount of time 
needed to install a purging system on an existing tank truck varied 
from 8 to 40 hours. While Cargo Tank Concepts provided the lowest 
estimate of 8 hours, an industry stakeholder with firsthand experience 
installing a purging system estimated that installation takes from 30 
to 34 hours of labor. The higher estimates include time to "de-gas" 
the cargo tank to reduce risk of explosion, increasing the cost of 
installation compared to that on new cargo tanks since those would not 
need to be de-gassed. PHMSA's regulatory assessment that considers 
different timeframes for implementing a wetlines rule assumes such 
retrofitting could be done concurrent with 5-year interval 
inspections, which involve de-gassing the tank.

* Delays: An industry analysis of PHMSA's proposed regulation and six 
industry stakeholders suggest that use of the purging system could 
delay drivers at fuel terminals, potentially causing backlogs, while 
others said that the purging system will not delay drivers because it 
can operate while drivers are completing necessary final steps before 
leaving a fuel terminal. One industry stakeholder said that the 
purging system would lengthen unloading times, since the system uses 
the truck's air compressor thereby lowering the pressure available for 
facilitating unloading and slowing unloading speeds. According to 
Cargo Tank Concepts, the system uses very little air, and air that is 
used is replaced quickly by the air compressor and therefore would 
have no impact on unloading.

* Vapor release: Because purging systems use air to push liquid into 
the tank, the systems increase the pressure in the tank. In 2005, the 
California Air Resources Board expressed concern that this increase 
would exceed the tank's design limit, causing it to vent gasoline 
vapor into the air potentially in violation of emissions limits, a 
concern echoed by one industry stakeholder we interviewed and in nine 
comments submitted in response to PHMSA's proposed 
regulation.[Footnote 49] However, according to Cargo Tank Concepts, 
the increase in air pressure is too small to trigger the pressure 
release valves and cause such release.

* Malfunction: Since PHMSA's proposed rule prohibits wetlines without 
adequate collision protection, in the event of a purging system 
malfunction, a truck would likely not be able to leave a terminal 
unless it could purge its bottom lines. One industry stakeholder was 
unsure how carriers would address the issue of potential malfunction 
of a purging system, but speculated that the truck would have to be 
off-loaded, potentially to another truck or, if the truck was at a 
fuel terminal, via an off-loading station. PHMSA officials said it 
might be possible to create a regulatory exception to allow one-time 
movement of the cargo to its unloading destination or to transfer the 
cargo to a different truck. In either case, the truck with a faulty 
system could then not be reloaded until after the purging system is 
repaired. Cargo Tank Concepts also noted that in the event of a 
purging system malfunction, only the product in the bottom lines would 
have to be removed, not the entire contents of the tank.

* Maintenance: Industry stakeholders agree that the purging system 
would result in additional maintenance and repair costs to the 
carrier. In comments submitted to PHMSA in response to the proposed 
rule, six industry stakeholders expressed concerns about the unknown 
cost of maintenance and repair of the purging system, as well as the 
absence of data on factors such as maintenance, reliability, down-
time, and repair and replacement costs. Two industry stakeholders we 
interviewed expressed concern that extreme operating conditions--very 
cold or hot climates, for example--could affect the system and 
therefore maintenance costs. However, according to one industry 
stakeholder familiar with the system, issues with the purging system 
are fairly easy to address. Cargo Tank Concepts commented that they 
have sold hundreds of purging systems that are operating reliably and 
incur low maintenance costs.

* Compliance: Four industry stakeholders said that compliance with 
PHMSA's proposed regulation could be an issue for carriers. One of 
those stakeholders said this could be a particular issue with the 
manual purging system that required drivers to proactively initiate 
purging, as some drivers may forget to initiate the purge, while 
others may skip purging to save time. Additionally, that stakeholder 
suggested that drivers may have a disincentive to purge bottom lines 
if using the vehicle's compressed air system for that purpose reduced 
the efficiency of other truck operations. Furthermore, according to 
two stakeholders, it could be difficult for carriers or third parties 
to verify compliance, given that some bottom lines lack glass panes 
that allow visual verification of the amount of liquid present in the 
bottom line. PHMSA officials did not view this as a major concern and 
told us that regulatory compliance cannot always be fully monitored. 
PHMSA also noted that carriers could choose other methods of 
eliminating wetlines besides the purging system.

Other Options to Address Wetline Safety Risks Are Not in Use, and Many 
Are Hypothetical: 

Stakeholders identified other options to address wetline safety risks 
in addition to the purging system. However, none of the other options 
are in use by the industry and many are hypothetical, making it is 
difficult to assess their costs, benefits, and feasibility. DOT 
summarized a number of options to address wetline safety risks in a 
1999 preliminary cost-benefit analysis, but additional information 
about options other than the purging system was limited to 
propositions and conjecture.[Footnote 50] Therefore, we relied on 
views from industry and safety stakeholders to determine the 
advantages and disadvantages of each option. Table 2 summarizes 
options and key advantages and disadvantages as identified by 
stakeholders.

Table 2: Stakeholders' Views on Options to Address Wetline Risks: 

Options: Purging system installed on the cargo tank truck; 
Description: After loading, system introduces compressed air from an 
auxiliary tank into the wetlines under low pressure, pushing liquid 
from the wetlines into the cargo tank body; 
Advantages: 
* Eliminates all but trace amounts of fuel from bottom lines; 
* May detect internal valve leaks; 
* Retrofit feasible; 
* Currently in use; 
Disadvantages: 
* If malfunctioning, other measures would be needed to empty wetlines; 
* Driver compliance with manual system difficult for carriers to 
enforce; 
* Opinions varied on consequences of low pressurization of an 
unpressurized tank; 
* Significant concern from industry over dangers of welding work 
needed for this option if DOT were to require retrofitting. 

Options: Purging system installed at the loading terminals; 
Description: After loading, the driver would connect to a stationary 
purging system. The system would then introduce air into the wetlines, 
forcing liquid from the wetlines into the cargo tank body; 
Advantages: 
Eliminates all but trace amounts of fuel from bottom lines; 
* May help detect leaks in cargo tank internal emergency valves; 
* Retrofit feasible; 
Disadvantages: Adds to time the driver spends at the terminal; 
* Difficult for carriers to enforce; 
* Requires modification to both trucks and terminals. 

Options: Short loading lines; 
Description: Shorter loading lines are added to tank trucks so that 
bottom lines are used only for unloading; 
Advantages: 
* Reduces the amount of liquid in external lines; 
* Lines would not be exposed to damage in the event of a rollover; 
Disadvantages: 
* Retrofit infeasible; 
* Greater distance between loading heads would necessitate 
modifications to either the loading rack or loading procedure, raising 
some cost and safety concerns. 

Options: Internal lines; 
Description: The horizontal components of bottom lines would be placed 
on the inside of tank compartments; 
Advantages: 
* Eliminates liquid in external lines; 
* Minimizes exposed elements; 
Disadvantages: 
* Retrofit infeasible; 
* Loading line leaks would no longer be visible and may contaminate 
liquid. 

Options: Double-closing stop valve; 
Description: Upon collision, a self-closing stop valve would protect 
against cargo tank spills while other closures would seal wetline ends; 
Advantages: 
* Reduces risk that designed-to-fail shear point will result in 
flammable liquid spill; 
* Retrofit feasible; 
Disadvantages: 
* Does not eliminate wetlines; 
* Stop valve could be damaged in the event of a collision; 
* To reduce wetline risk further would require stronger pipes, like 
the protection of tanks for trucks carrying propane. 

Options: Top loading; 
Description: Cargo tank trucks would be loaded from the top of the 
tank; 
Advantages: 
* Eliminates liquid in external lines; 
Disadvantages: 
* Modifications necessary to meet vapor recovery requirements, address 
issues of worker safety; 
* Requires reconfiguration of loading racks. 

Options: Draining wetlines at the terminal; 
Description: After loading the truck and closing the valves the 
carrier would reconnect to a tank (either at the rack or elsewhere in 
the terminal) and drain the liquid in the bottom lines; 
Advantages: 
* Eliminates liquid in external lines; 
* Terminals currently have storage tanks for "slop"; 
Disadvantages: 
* Terminals would need new administrative processes, revised automated 
metering, and additional storage--possibly separate storage unit for 
each liquid; 
* Mixing products would inhibit resale; if unable to be sold, would 
create hazardous waste. 

Options: Guards, shields, or under-ride protection; 
Description: Cargo tank trucks would be equipped with bottom damage 
protection devices; 
Advantages: 
* Reduces risk of wetline rupture; 
Disadvantages: Does not eliminate wetlines; 
* Retrofit inadvisable, possibly infeasible; 
* Added weight of guards would reduce the carrying capacity of tank 
trucks; 
* In a collision, the guards could puncture the tank or transfer force 
and cause the tank to rupture; 
* Guards to prevent pedestrian and bicycle under-rides would not 
sufficiently protect the tank. 

Source: GAO analysis of documents from DOT's 2004 and 2011 proposed 
regulations to address wetline safety risk, as well as interviews with 
PHMSA, NTSB, Cargo Tank Concepts, industry stakeholders, and safety 
groups. 

[End of table] 

For all the options, the most obvious advantage is the potential to 
address wetline safety risks, but according to stakeholders, the 
extent that these options address those risks varies. Some options 
would leave traces of fuel in the cargo tank trucks' bottom lines, 
while others would retain wetlines but potentially reduce risk by 
shielding them or altering wetline design to minimize spillage in the 
event of a collision.

Some stakeholders' concerns with the wetline purging system apply to 
other options as well, such as concerns about the safety of 
retrofitting cargo tank trucks. For at least three of the other 
options, retrofits are either not feasible or inadvisable, which would 
mean these options could only be implemented on new tank trucks, 
delaying safety benefits. In addition, the entity that would bear the 
initial cost of implementation varies among the options. For example, 
one stakeholder said that carriers would bear the initial cost of 
installing side-guards on tank trucks to shield them from collisions, 
since that option would require changes to the cargo tank design. In 
contrast, short loading lines that would replace the longer bottom 
lines for loading tanks could require changes to the cargo tank design 
and modifications to the loading rack, so the carriers and the fuel 
terminals would both incur initial costs. Stakeholders suggested that 
other agencies, such as the Environmental Protection Agency or the 
Occupational Safety and Health Administration, may need to be 
consulted on the design and implementation of some options due to 
potential environmental and/or worker-safety concerns.

PHMSA Analyzed Costs and Benefits for a Proposed Wetlines Rule, but 
Uncertainties Limit the Usefulness of the Analysis: 

PHMSA Proposed a Rule to Address Wetline Safety Risks and Analyzed 
Associated Costs and Benefits: 

In January 2011, PHMSA issued a notice of proposed rulemaking to 
prohibit the transport of flammable liquid in the bottom lines of 
cargo tank trucks unless the vehicle is equipped with bottom damage 
protection devices, along with an analysis of the proposal's costs and 
benefits. In March 2012, PHMSA updated the assumptions of its cost-
benefit analysis in response to comments submitted by stakeholders in 
the rulemaking and also changed its methodology (for discussion of the 
changed methodology, see appendix II). We reviewed the assumptions and 
methodology in the March 2012 working draft document because they 
reflected PHMSA's more current thinking; however, this document was 
provided in draft form and has not been released publicly. PHMSA has 
not issued a final rule on this subject; therefore, information in 
either the 2011 or 2012 analysis is subject to change. PHMSA officials 
told us they ceased all work on the rulemaking in response to the MAP-
21 requirement that PHMSA not issue a final rule pending the 
completion of our study. PHMSA may, however, issue a rule earlier if 
it determines that a risk to public safety, property, or the 
environment is present or an imminent hazard exists and that the 
regulation will address the risk or hazard.

PHMSA based its cost-benefit analysis on the assumption that the 
industry would comply with the proposed rule by installing a wetline 
purging system on cargo tank trucks--specifically the manual version 
of the system offered by Cargo Tank Concepts.[Footnote 51] PHMSA's 
analysis included multiple compliance scenarios that varied in the 
amount of time the industry would have to comply with the rule. The 
longest scenario called for compliance within 20 years, which, given 
PHMSA's assumption that tank trucks have a 20-year life, would mean 
the device could be installed on only new trucks and no retrofitting 
would be needed. The shortest scenario called for compliance within 5 
years and assumed the industry would retrofit many of its existing 
tank trucks concurrently with a truck's required 5-year inspection, at 
which time PHMSA officials told us trucks are cleaned of gasoline and 
vapor as part of the inspection process, reducing the risk of 
explosion from welding on an existing tank.

PHMSA's 2011 analysis found that costs exceeded benefits in all of the 
compliance scenarios, while the 2012 analysis concluded that benefits 
exceeded costs on a present value basis by about $2 million in the 20-
year scenario; but costs exceeded benefits in the three scenarios with 
shorter compliance time frames. Table 3 describes the costs and 
benefits considered in the analysis.

Table 3: Costs and Benefits Included in PHMSA's 2011 Cost-Benefit 
Analysis and Its 2012 Draft Revision: 

Costs: 
* Purchase and installation of manual wetline purging systems on all 
cargo tank trucks; 
* Annual maintenance of purging systems; 
* Weight penalty, resulting from the reduced carrying capacity of a 
tank truck to account for the weight of the purging system[A; 
* For the 2012 analysis, PHMSA also included additional operating 
costs that carriers would incur to transport product displaced by the 
added weight of the purging system; 

Benefits: 
* Avoidance of all wetline incidents, including associated fatalities, 
product loss, clean-up costs, carrier damage, and property damage. 
(The 2011 analysis also included evacuation delays, but this was 
removed in the 2012 analysis); 
* Avoidance of associated consequences, such as traffic delays and 
risk to emergency responders; 
* Avoidance of a low-probability, high-consequence event such as the 
1997 Yonkers incident. 

Source: GAO analysis of PHMSA's 2011 cost-benefit analysis and 2012 
working draft cost-benefit analysis.

[A] Federal regulation limits the weight of commercial vehicles on the 
interstate highway system, see 23 C.F.R. part 658. In general, off the 
interstate highway system, states may set their own commercial vehicle 
weight standards. Therefore, the added weight of a purging system 
could result in decreased product carrying capacity. 

[End of table] 

PHMSA withdrew a previous proposed wetlines rule in 2006 because it 
determined that the rule's potential benefits did not justify its 
costs. The agency issued its more recent proposal in 2011 because the 
agency still views preventing wetline incidents as an important safety 
issue and, according to PHMSA officials, given further development of 
the wetline purging system, preventing wetline incidents can now be 
done in a manner that is cost-beneficial. In contrast, 11 of the 12 
industry stakeholders we spoke with opposed the proposed rule for 
reasons such as their belief that wetlines are not a major safety 
issue and their concerns about the possible solutions, which were 
previously discussed in this report.[Footnote 52] Six of the 10 safety 
stakeholders we interviewed supported the rule, while three others 
took no position. Four other safety groups we contacted declined to be 
interviewed because they had no position on the issue.

Uncertainty Associated with Aspects of PHMSA's Cost-Benefit Analysis 
Limits Its Usefulness for Supporting the Proposed Rule: 

OMB has issued guidance for agencies engaged in rulemaking on the use 
of data and treatment of uncertainty in cost-benefit analysis. 
[Footnote 53] The guidance states that market data is a rich source of 
information, and that estimating cost when active markets do not exist 
is more difficult, requiring appropriate proxies. Accordingly, an 
agency should discuss the quality of available data used and in the 
absence of adequate data, the agency will need to make certain 
assumptions. With regard to uncertainty, the guidance states that 
estimates of benefits and costs are typically uncertain because of 
imprecision in underlying data and assumptions. Because uncertainty is 
common when conducting cost-benefit analysis, OMB states that the 
effects of uncertainty should be analyzed and reported. To address 
plausible changes in the assumptions and numeric inputs of a cost-
benefit analysis, OMB recommends that agencies consider providing a 
sensitivity analysis to show how the results of the analysis might 
vary to account for such uncertainty. Limitations of the analysis 
because of uncertainty or biases surrounding data or assumptions 
should, according to OMB, be discussed. Additionally, the OMB guidance 
provides that when uncertainty has significant effects on the final 
conclusion about net benefits, the agency should consider additional 
research prior to rulemaking.

PHMSA's calculated benefits are based on the assumption that use of 
the purging system by tank truck carriers will prevent all wetline 
incidents; the value of this benefit is based on PHMSA's analysis of 
its past incident data to identify wetline incidents and their 
associated consequences. Other assumptions in the analysis are based 
on testimonial information and observation, rather than market data. 
Specifically, cost calculations are based on information from the 
purging system's manufacturer regarding the purchase and installation 
costs of the technology. Additionally, information about purging 
system performance--an input that can affect both benefits and costs--
is based on 1) information from the manufacturer, 2) anecdotal 
information about the performance of the technology provided by the 
major carrier that is using the automatic version of the system, and 
3) PHMSA's observation of a prototype version of the manual purging 
system that shows how the technology works but is not actually 
installed on a tank truck. Although PHMSA included sensitivity 
analyses in its 2011 and 2012 cost-benefit analyses to account for 
some uncertainties, issues with the data and assumptions that can 
affect costs and benefits were not addressed through sensitivity 
analysis.[Footnote 54] Consequently, some costs and benefits in the 
analysis may be more uncertain than PHMSA has accounted for.

Cost Assumptions: 

PHMSA's analysis assumes a cost of $2,300 to equip each new or 
existing cargo tank truck with a manual wetline purging system, plus 
the cost of installation labor, rather than the higher cost of the 
automatic version currently used, which the manufacturer sells for 
$3,800 or $3,950 depending on the size of the tank truck.[Footnote 55] 
PHMSA assumed companies would opt for the manual system because of its 
lower cost and used that as the cost basis in its analysis. As 
previously discussed, there are no manual systems in use to date, and 
some industry stakeholders suggested that carriers may prefer the 
automatic system for compliance and simplicity reasons, despite its 
higher cost. Thus, although there is a limited market for the 
automatic purging system, the lack of market use to date for the 
manual system makes the cost of compliance with the regulation 
uncertain despite a stated price from the manufacturer.

Were the proposed rule issued, such action would likely generate 
demand for the purging technology, which could have several effects. 
Specifically, it could enable the product to be produced at a lower 
cost due to achieving economies of scale related to a higher level of 
production, and it could also attract more companies into the market 
to produce alternative purging systems. Although we are aware of only 
one company offering purging system technology at the time of our 
review, at least three patents for other purging systems have been 
granted, making industry competition a possibility. Consequently, in 
the absence of market-based information for the manual purging system, 
it is difficult to develop assumptions on the cost of the technology 
for the cost-benefit analysis. While these factors could have an 
impact on the sales price of the unit, PHMSA's analysis does not fully 
account for these cost uncertainties and, to the extent that market 
information exists for the automatic purging system, such information 
is not used to support costs in the analysis. PHMSA's analysis 
presents a sensitivity analysis only for a lower cost of the purging 
system on the basis that a more competitive market could develop if 
its proposed rule were finalized and that the manufacturer recently 
began offering the manual purging system at a lower price.

Additionally, stakeholders we spoke with mentioned a number of other 
cost-related concerns: 

* Installation approach. As previously discussed, stakeholders raised 
safety concerns about potential welded retrofitting needed to install 
purging systems under the shorter compliance scenarios, due to the 
risk of explosion if cargo tanks are not thoroughly de-gassed. Safety 
measures to address these concerns could add additional cost. However, 
PHMSA's analysis addressed these concerns by stating that carriers 
could install nonwelded purging systems. PHMSA officials also told us 
that because the compliance scenarios were created with 5-year 
intervals, retrofitting could occur concurrently with 5-year 
inspections when tanks are normally cleared of flammable product and 
vapor. PHMSA officials also stated that there are procedures to de-gas 
tanks to make them safe for such work.

* Installation time. PHMSA's analysis does not include the cost of 
down-time to install the purging system, even for scenarios requiring 
retrofitting because the analysis assumes the work can be done 
concurrently with routine inspections. However, stakeholders reported 
a range of time needed to install a purging system, which could take 
longer than the inspections; thus it is unclear that the inspection 
and retrofitting could actually be done simultaneously.

* Maintenance. PHMSA assumes maintenance on a purging system will cost 
$3 per year per truck, based on an assumption about the cost of 
inspecting the device every 5 years. Stakeholders with experience 
using the technology said this cost is too low and told us the 
technology required occasional repairs or replacement. According to 
PHMSA's analysis, it includes a low-cost maintenance estimate because 
it states that pneumatic technologies like the purging system require 
very little maintenance because they have few moving parts that can 
fail.

We also found uncertainty in PHMSA's data and assumptions related to 
benefits: 

* Fatalities. As previously discussed, we identified inaccuracies in 
PHMSA's analysis regarding the number of fatalities that could be 
avoided by the proposed wetlines rule, and PHMSA did not include a 
sensitivity analysis to account for its rule potentially preventing 
fewer deaths than assumed in its cost-benefit analysis. Both the 2011 
and 2012 cost-benefit analyses stated there were 4 incidents with 
hazmat-related fatalities during the incident study period (resulting 
in 5 fatalities).[Footnote 56] After discussing the inaccuracies with 
PHMSA officials, they agreed it would be more accurate for their 
analysis to reflect 4 fatalities occurring from 3 fatal wetline 
incidents. Questions over PHMSA's wetline fatality analysis have been 
raised before. In a 2001 letter critiquing a prior wetlines proposed 
rule, OMB encouraged DOT to more fully address the uncertainty in the 
cause of fatalities in its wetlines cost-benefit analysis, 
specifically to address uncertainty with whether fatalities might be 
caused by factors other than the release of hazardous materials and 
would therefore not be avoided by a rule addressing wetlines.

* Because fatalities are a major contributor to the calculated value 
of the benefits of the regulation, a reduction of even one fatality in 
the analysis could have significant impact on the amount of calculated 
benefits for the proposed rule.[Footnote 57] For example, PHMSA's 2012 
analysis concluded that with 4 fatal incidents during the study period 
and an average of 1.67 people per vehicle, the proposed rule would 
avoid 6.7 fatalities for a benefit of about $3.4 million per year. 
[Footnote 58] Were the analysis recalculated with 3 fatal incidents, 
the annual benefit of avoided fatalities would be about $2.5 million 
per year, about $1 million less. This is significant, given that 
avoided fatalities comprise more than half of the almost $6.5 million 
total annual benefit of the proposed rule. In the 2012 draft cost-
benefit analysis, PHMSA's 20-year compliance scenario showed a total 
net benefit of about $2 million, which was the only scenario where 
benefits exceeded costs. Thus, while PHMSA has not issued a final rule 
on this subject and information in either the 2011 or draft 2012 
analysis is subject to change, had the analysis been calculated with 
one less fatal incident, costs would have exceeded benefits in that 
scenario as well.

* Effectiveness. PHMSA's analysis assumes its proposed rule would 
prevent all wetline incidents, implying that the purging systems 
installed to prevent these incidents would be 100 percent effective. 
However, PHMSA's analysis does not acknowledge that the system may 
malfunction, may not prevent wetline incidents due to certain 
intervening factors, and that the system may not always be used as 
intended. We are aware of two wetline incidents that have occurred 
since 2008 involving trucks equipped with an automatic wetline purging 
system. According to the carrier involved in both incidents, in one 
instance, the driver had turned off the system and, in the other, a 
problem with the lining of the cargo tank prevented the system from 
functioning properly. Based on this information, it does not appear 
there was a functional problem with the purging device in either 
instance; however, wetline incidents occurred nonetheless.

* Most Catastrophic Incident. PHMSA's 2011 and 2012 analyses included 
additional benefits from avoiding a low-probability, high-consequence 
event like the 1997 Yonkers incident. Even though the Yonkers incident 
occurred prior to the years for which data were used for the primary 
analysis of expected benefits, this incident was included in the 
analysis--meaning that it comprised a portion of the expected benefits 
due to accidents avoided--under the assumption that a severe incident 
such as this would happen very infrequently. Specifically, in both of 
these analyses, the expected benefits of avoiding an incident of this 
level of consequence were allocated over a 20-year period--meaning 
that the agency assumed such a catastrophic incident could be expected 
to occur once every 20 years. PHMSA officials told us they considered 
allocating the benefits over a longer 40-year period in response to 
industry criticism that there has been only one such extraordinary 
incident on record but that the agency has not reached a final 
decision on this issue. When assumed to be a 20-year event, the 
expected benefits of avoiding a Yonkers-like incident in the 2012 
benefit cost analysis comprise about 1/3 of the proposed rule's 
benefits. Given the apparent rarity of such an incident, it is 
uncertain whether 20 years, 40 years, or some other time period is an 
appropriate assumption of the frequency of such an event. However, 
PHMSA did not account for this uncertainty in a sensitivity analysis.

Conclusions: 

Wetline incidents have ranged from minor incidents to serious 
accidents that have claimed lives and damaged property. Because PHMSA 
does not specifically provide an option to indicate a wetline incident 
on its incident reporting form, it is difficult to identify the number 
of wetline incidents from PHMSA's incident data. Additionally, due to 
inaccuracies in the data, the magnitude of the risk they pose to 
safety is also unclear. Although PHMSA has made changes to improve the 
quality of its incident data, the concerns we identified call into 
question the data's usefulness for characterizing key aspects of the 
benefits of avoiding these incidents, particularly the extent to which 
a wetlines rule would prevent fatalities. Furthermore, PHMSA's 
economic analysis does not account for these limitations. Thus, the 
analysis does not adequately convey the uncertainty of PHMSA's 
calculated benefit of the rule. Furthermore, PHMSA's analysis has not 
adequately addressed the market uncertainty with regard to the cost of 
the purging system, given that it is in limited use and the particular 
version of the system assumed in the analysis, to date, has not been 
in use.

While NTSB has called on PHMSA to address wetline risks, industry 
stakeholders have raised concerns about PHMSA's proposed regulation, 
particularly given that they view wetline incidents as occurring 
infrequently and that there could be other safety risks with the 
assumed option to address wetline safety risks. Without adjusting its 
cost-benefit analysis to account for the uncertainties due to the 
limited market for the purging system and limitations with PHMSA's 
incident data, the consequences of wetline incidents remain unclear 
and the costs and benefits of wetline regulation may not be accurately 
calculated in PHMSA's regulatory analysis.

Recommendations for Executive Action: 

To improve the reliability of data used to identify wetline incidents, 
we recommend that the Secretary of Transportation direct the 
Administrator of PHMSA to take the following two actions: 

* Revise incident reporting to better capture wetline incidents and 
their consequences, such as by requiring specific reporting of wetline 
incidents by modifying the reporting form to include a specific 
indicator of such incidents, and adjusting the incident reporting form 
to indicate whether there are minimal costs versus no costs when costs 
are below the $500 reporting threshold.

* Address limitations with the accuracy and completeness of 
information used to assess the impact of wetline incidents, such as by 
specifying circumstances when PHMSA should seek missing cause and cost 
information, and potentially using sources other than the carrier to 
acquire information (such as investigations by local law enforcement 
or other federal agencies), particularly for the most severe incidents 
for which having accurate incident information is critical to oversight.

To strengthen the agency's rulemaking analysis, we recommend that the 
Secretary of Transportation direct the Administrator of PHMSA to take 
the following action: 

* Strengthen the regulatory assessment of the proposed wetline rule's 
costs and benefits to better address the uncertainty of underlying 
factors. Such action could include incorporating more real-world 
information about purging systems or, if considered, other wetline 
solutions, and conducting additional sensitivity analyses for areas of 
uncertainty that are not addressed by improved data collection.

Agency Comments: 

We provided a draft of this report to the Department of Transportation 
for review and comment. DOT indicated that PHMSA would take this 
report into consideration as it continues to consider rulemaking and 
works to improve its incident data collection and internal review 
procedures. The department did not agree or disagree with our 
recommendations, but provided technical comments that we incorporated 
as appropriate.

We are sending copies of this report to the appropriate congressional 
committees, the Secretary of Transportation, and other interested 
parties. In addition, the report is available at no charge on the GAO 
website at [hyperlink, http://www.gao.gov].

If you or your staff have any questions about this report, please 
contact me at (202) 512-2834 or flemings@gao.gov. Contact points for 
our Offices of Congressional Relations and Public Affairs may be found 
on the last page of this report. GAO staff who made key contributions 
to this report are listed in appendix III. 

Signed by: 

Susan A. Fleming: 
Director, Physical Infrastructure Issues: 

[End of section] 

Appendix I: Objectives, Scope, and Methodology: 

Objectives: 

This report discusses (1) the extent that the Pipeline and Hazardous 
Materials Safety Administration's (PHMSA) data can be used to reliably 
identify wetline safety risks, (2) options for addressing wetline 
safety risks, and (3) how well PHMSA has assessed the costs and 
benefits of addressing these risks through regulation.

Scope and Methodology: 

To evaluate the extent that PHMSA's data reliably capture wetline 
incidents, we examined PHMSA's process for identifying wetline 
incidents and the data for the incidents that the agency has 
identified as being wetline-related occurring from the beginning of 
January 1999 to the end of March 2011. Our evaluation assessed PHMSA's 
efforts against federal internal control standards that require 
agencies to have relevant, reliable, and timely information for 
decision-making and external reporting purposes, and Office of 
Management and Budget (OMB) data quality guidelines for regulatory 
purposes.[Footnote 59] Specifically, we analyzed the narrative 
information for these incidents to determine how useful this 
information is for identifying the incidents as being wetline-related. 
We examined the extent to which the incidents' coding of the component 
of the tank truck that failed could be indicative of a wetline 
incident. We also examined the extent to which these data accurately 
reported information about incident fatalities and to what extent they 
reported information about other incident damages. We selected 12 
incidents to review as case studies to learn more about PHMSA's 
process for recording information about these incidents and to look 
for potential irregularities between PHMSA's database and other 
available information about the incidents. We selected these incidents 
to span the 1999 to 2011 time frame, to represent a range of minor to 
major incidents as measured by reported fatalities and other damages, 
and to include any incidents that were investigated by PHMSA or the 
National Transportation Safety Board (NTSB). We also included two 
incidents that PHMSA had determined to be wetline-related in its 2011 
analysis but later determined not to be wetline incidents in its draft 
2012 analysis.[Footnote 60] We reviewed the reliability of these 
incident data by examining them for missing data and inconsistencies, 
reviewing PHMSA's process for obtaining wetline data and maintaining 
them in the agency's database, and related internal controls. We 
concluded that the data were sufficiently reliable for the purposes of 
our report. Our conclusion that PHMSA's incident data are not 
sufficiently reliable for use in its regulatory analysis is 
independent of our conclusion that the data are sufficiently reliable 
for our purpose, since our purpose was to assess to what extent the 
data reliably identify wetline incidents and their characteristics. 
Based on the information PHMSA provided about how it uses these data 
for this purpose and the availability of PHMSA's incident data through 
its online incident database, we were able to make this assessment. We 
reviewed documents on and interviewed PHMSA officials about the 
agency's prior and ongoing efforts to improve the quality of its 
hazmat incident data.[Footnote 61] Since our review focuses 
specifically on the issue of wetlines, we did not assess PHMSA's 
progress in improving its hazardous materials incident data in general.

To describe options to address wetline safety risks, we reviewed 
documentation from PHMSA's current and most recent prior related 
rulemaking efforts to identify what options have been proposed to 
address wetline safety risks and which major safety and industry 
stakeholders have been engaged on this issue. For contextual 
information about the feasibility of these options, we also visited a 
fuel terminal where cargo tank trucks are loaded. We reviewed 
documents from and interviewed associations and experts representing 
safety advocacy and various components of industry involved in the 
transportation of flammable liquids to understand stakeholder views on 
the options to address wetline safety risks. Specific stakeholders we 
interviewed are listed in table 4.

Table 4: Wetline Industry and Safety Stakeholders Interviewed: 

Industry stakeholder (segment): 
* American Petroleum Institute (oil and natural gas industry); 
* American Trucking Associations (trucking industry); 
* Baltimore Cargo Tank Services (tank truck repair and service 
company); 
* Dangerous Goods Advisory Council (hazardous materials transportation 
safety organization); 
* Independent Fuel Terminal Operators Association (terminals for 
distributing flammable liquid products); 
* International Liquid Terminals Association (terminals for 
distributing flammable and other liquid products); 
* National Tank Truck Carriers (tank truck carriers); 
* Petroleum Marketers Association of American (petroleum marketing 
trade associations); 
* Renewable Fuels Association (ethanol producers); 
* Society of Independent Gasoline Marketers of America (marketers of 
petroleum products); 
* Sunoco (petroleum marketer, carrier, and terminal operator); 
* Truck Trailer Manufacturers Association (tank truck manufacturers). 

Safety stakeholder (segment)[A]: 
* Advocates for Highway and Auto Safety (consumer, health, safety, and 
insurance alliance); 
* Bob Chipkevich (transportation safety consultant); 
* Commercial Vehicle Safety Alliance (association of government motor 
carrier safety officials); 
* International Association of Fire Chiefs (emergency response 
officials); 
* International Brotherhood of Teamsters (labor union); 
* Joe Connelly (hazardous materials safety consultant); 
* National Association of State Fire Marshals (state fire response 
officials); 
* National Board of Boiler and Pressure Vessel Inspectors[B] (tank 
inspection, safety, training and standards); 
* NTSB (federal incident investigation)[C]; 
* Truck Safety Coalition (public safety). 

Source: GAO.

[A] We contacted four other safety organizations that declined to be 
interviewed because they were not actively working on or did not have 
a position on the issue of wetline safety. These were American 
Association of Motor Vehicle Administrators, American Association of 
State Highway and Transportation Officials, Governors Highway Safety 
Association, and Insurance Institute for Highway Safety.

[B] We requested an interview with the National Board of Boiler and 
Pressure Vessel Inspectors, which instead provided written answers to 
our questions.

[C] Although NTSB is a government agency, in the context of this 
engagement we considered it a safety stakeholder due to its expertise 
having investigated wetline incidents and its recommendation that DOT 
prohibit wetlines. 

[End of table] 

We placed particular focus on examining the wetline purging system, 
since it is the option used in PHMSA's wetlines rulemaking analysis 
and the only option we are aware of that has been installed to address 
wetline risks. To better describe this option, we reviewed 
documentation about the system and interviewed the system 
manufacturer, Cargo Tank Concepts. We also interviewed stakeholders 
with direct experience with the system. We interviewed Sunoco--a 
petroleum marketer, carrier, and terminal operator that has installed 
the system on its tank truck fleet--and visited a Sunoco terminal near 
Philadelphia, Pennsylvania, that distributes flammable liquid products 
to tank trucks equipped with the purging system. We also interviewed 
Baltimore Cargo Tank Services, a tank service company that has 
installed the system on tank trucks. Based on reviews of patent 
applications and an industry trade publication, we identified other 
companies that may be able to produce similar wetline purging 
technology and interviewed two of them: Civacon and Franklin Fueling 
Systems.

Because most of the options to address wetline safety risks are 
theoretical--and the one solution that has been implemented is not 
widespread--our ability to present specific information about 
solutions' costs and benefits was limited. Instead, we focused on 
identifying to what extent stakeholders agree or disagree on 
information about these options, including the feasibility of 
implementing them in the current operating environment.

To evaluate how well PHMSA has assessed the costs and benefits of 
addressing wetline risks through regulation, we reviewed prior 
Department of Transportation rulemakings on wetlines to understand the 
history of the agency's work on this issue and focused our analysis on 
the current proposed rule, beginning with the Notice of Proposed 
Rulemaking that PHMSA issued in January 2011. We analyzed PHMSA's 
January 2011 cost-benefit analysis and an updated working draft 
version of the analysis from March 2012. We reviewed PHMSA's process 
and assumptions used for developing these analyses and the reasons for 
changes between them. We reviewed comments in the rulemaking record 
and interviewed stakeholders about their views on PHMSA's efforts to 
address wetline safety risks. We assessed PHMSA's efforts against OMB 
guidance for use of data and cost-benefit analysis to support 
rulemaking.[Footnote 62] We also reviewed PHMSA's non-regulatory 
efforts to address wetline safety risks, which consisted of an effort 
to raise awareness of emergency responders, following the agency's 
withdrawal of its most recent prior proposed rule in 2006.

We conducted this performance audit from September 2012 to September 
2013 in accordance with generally accepted government auditing 
standards. Those standards require that we plan and perform the audit 
to obtain sufficient, appropriate evidence to provide a reasonable 
basis for our findings and conclusions based on our audit objectives. 
We believe that the evidence obtained provides a reasonable basis for 
our findings and conclusions based on our audit objectives. 

[End of section] 

Appendix II: PHMSA's Wetline Proposed-Rule Cost-Benefit Methodology 
and Related Changes: 

To support its proposed wetline rule, PHMSA developed analyses of the 
rule's costs and benefits: PHMSA released a first analysis with the 
proposed rule in January 2011 and provided us a working draft of an 
updated analysis from March 2012 that the agency did not release 
publicly. In updating its cost-benefit analysis in 2012, PHMSA made 
several changes to its methodology for calculating costs and benefits 
that affect the outcomes of the analysis and may affect the ability to 
compare its scenarios.

Both the 2011 and 2012 analyses are built on the assumption that tank 
trucks have a useful life of 20 years. Therefore, the entire tank 
truck fleet in existence at the time of a rule's effective date would 
presumably be replaced during the course of the 20 years that 
followed. The 2011 and draft 2012 analyses include four alternative 
scenarios with varying time periods for achieving compliance with the 
proposed rule--specifically in 5, 10, 15, or 20 years. Were a rule to 
require compliance within 20 years, carriers could achieve compliance 
by equipping only new trucks with a wetline purging system. If 
compliance were required sooner, some degree of retrofitting of 
existing tank trucks would be required, in addition to equipping any 
vehicles that are new in the compliance timeframe.

All four scenarios in the 2011 analysis were analyzed over a 20-year 
timeframe. The primary cost in the 2011 analysis is the installation 
of wetline purging systems over a 20-year period, which included all 
new tank trucks during that time and, in the case of the three shorter 
compliance scenarios, the additional cost of retrofitting some tank 
trucks that would not have been replaced by the time compliance was 
required. Benefits in the 2011 analysis were the value of associated 
fatalities and other damages from wetline incidents the rule is 
assumed to avoid over the 20-year period. In the 2011 analysis, 
benefits are greater in the shorter compliance scenarios because tank 
trucks are equipped with purging systems sooner and therefore more 
incidents are avoided. In the 20-year scenario, only 5 percent of 
trucks are equipped each year so it takes until year 20 when all 
vehicles would be equipped and all incidents in that year would be 
avoided.[Footnote 63] In contrast, in the 5-year compliance scenario, 
by year 5, all future incidents are assumed to be avoided, resulting 
in greater estimated benefit, but also increased cost, due to the need 
to equip sooner--requiring many trucks to be retrofit with purging 
systems--and the continued cost of equipping trucks in years 6-20 as 
retrofitted trucks need replacement.

In contrast, the 2012 cost-benefit analysis did not calculate all 
costs and benefits of the rule over a 20-year period, but rather 
calculated costs for each truck required to be equipped with a purging 
system within the compliance time frame and the benefits associated 
with that equipage for the remaining life of each equipped truck. This 
changes the number of years over which costs and benefits are 
calculated: 

* For the 20-year compliance scenario, the 2012 analysis includes 
costs for equipping all new tank trucks purchased during the 20 years, 
and measures benefits for 20 years after each truck is equipped. That 
is, a truck that is bought new in year 15 will have benefits 
associated with that equipage until year 35.

* For the 5-year compliance scenario, all trucks are either equipped 
new or retrofit during the first 5 years, and the benefits associated 
with the remaining life of that truck are assessed. While trucks 
purchased new in those 5 years will have benefits measured over the 20-
year life of each truck, the benefits associated with the retrofit 
trucks are calculated for a shorter period of time depending on 
PHMSA's assumptions about the remaining life of those vehicles. 
Benefits accrue until a retrofitted truck is presumed retired from 
service.

PHMSA did not include in its 2012 assessment the costs or benefits 
associated with a new truck that would replace the truck that had been 
retrofit. For example, if a truck was retrofit in year 3 of the 
analysis and it was assumed that it had a remaining life of 10 years, 
benefits associated with that truck were included in the analysis only 
through year 13; the costs from equipping a new replacement truck in 
year 13 and the resulting benefits thereafter were not included. 
Consequently, the 2012 analysis may not be comparable with the 2011 
analysis, which used the same 20-year time-frame for the four 
scenarios.[Footnote 64] Further, this methodology does not show that 
equipping trucks sooner would result in greater societal benefit, 
likely because benefits are not included for new trucks that would 
replace retrofit trucks retired within the 20 year timeframe. Rather, 
it shows the value of benefits as greater under the longer compliance 
timeframe. In contrast, the 2011 analysis shows greater benefit for 
the 5-year compliance scenario than the 20-year scenario, but at 
significantly higher cost. Table 5 compares the cost and benefit 
values and calculation methods for the 20-year and 5-year compliance 
scenarios in PHMSA's 2011 and 2012 analyses.

Table 5: Cost and Benefit Values and Calculation Methodologies from 
PHMSA's 2011 and 2012 Wetline Proposed-Rule Cost-Benefit Analyses: 

2011 analysis: 

20-year compliance scenario: 

Costs[A]: $52.5 million; 
Cost based on equipping only new trucks, resulting in 27,000 equipages 
that occur over 20 years; 

Benefits[A]: $51.6 million; 
Benefits are the value of wetline incidents avoided during the 20-year 
period. Thus, with an equal number of new trucks equipped each year, 
more incidents are avoided in later years than in early years. 

5-year compliance scenario: 

Costs[A]: $100.6 million; 
Cost based on equipping new trucks, resulting in 27,000 new equipages 
that occur over 20 years, and retrofitting existing trucks in use by 
the end of the first 5 years, resulting in 20,500 retrofits over the 
first 5 years; 

Benefits[A]: $94.7 million; 
Benefits are the value of wetline incidents avoided during the 20-year 
period. Thus, all wetline incidents are avoided after the first 5 
years, since all trucks are equipped by the fifth year, and a 
percentage of incidents are avoided each of the first 5 years based on 
how many trucks would be equipped that year. 

2012 analysis: 

20-year compliance scenario; 

Costs[A]: $65.4 million; 
Cost is based on equipping only new trucks, resulting in 27,000 
equipages that occur over 20 years. 

Benefits[A]: $67.3 million;
Benefits are calculated for the useful life of each equipage: thus 
benefits are calculated for 20 years for every truck, since all 
equipages are on new trucks expected to last 20 years. 

5-year compliance scenario: 

Costs[A]: $74.6 million; 
Cost is based on equipping new trucks during the first 5 years and 
retrofitting all other trucks during that period, resulting in 27,000 
equipages over 5 years. 

Benefits[A]: $54.1 million; 
Benefits are calculated for the useful life of each equipage: thus 
benefits are calculated for 20 years for every new truck, and for 
fewer years for each retrofitted truck. 

Source: GAO analysis of PHMSA cost-benefit analyses: 

[A] Values are present value 2009 dollars PHMSA discounted using a 3 
percent discount rate. PHMSA also calculated costs and benefits using 
a 7 percent discount rate. 

[End of table] 

[End of section] 

Appendix III: GAO Contact and Staff Acknowledgments: 

GAO Contact: 

Susan A. Fleming, 202-512-2834, flemings@gao.gov: 

Staff Acknowledgments: 

In addition to the individual named above, Sara Vermillion, Assistant 
Director; Amy Abramowitz; Melissa Bodeau; Geoff Hamilton; Andrew 
Huddleston; Tara Jayant; SaraAnn Moessbauer; Jaclyn Nelson; Josh 
Ormond; Madhav Panwar; Lisa Shibata; and Anne Stevens made key 
contributions to this report.

[End of section] 

Footnotes: 

[1] Pub L. No. 112-141, 126 Stat. 405, 840-41 (2012). Section 33015 of 
MAP-21 prohibits DOT from issuing a wetlines final rule prior to 
either the completion of our mandated study or until July 2014, 
whichever is earlier, unless DOT determines that a risk to public 
safety, property, or the environment is present or an imminent hazard 
exists and that the regulations will address the risk or hazard.

[2] We examined incident data from January 1999 through March 2011 
because this is the period of time of the incidents PHMSA used to 
support its wetline rulemaking.

[3] The exact number of cargo tank trucks operating in the United 
States is unknown since DOT does not track this information. For the 
purposes of the proposed wetline rule, PHMSA's regulatory assessment 
assumes a total of 27,000 tank trucks would be affected by a rule. 
Citing others' research, NTSB has indicated that other estimates have 
ranged from about 10,000 to 60,000 tank trucks. See NTSB, Safety 
Recommendation, H-11-1 (Washington, D.C.: Sept. 2, 2011).

[4] Bottom damage protection devices must meet the requirements of 49 
C.F.R. §178.337-10, 49 C.F.R. §178.345-8(b), or the accident damage 
protection requirements of the specification under which the cargo 
tank motor vehicle was manufactured.

[5] Volatile organic compounds present in vented gas are contributors 
to elevated ozone and haze. 

[6] The carrier is the company with physical control of the shipment 
during its transportation, which may or may not be the same as the 
shipper, i.e., the company originally providing the product. Carriers 
transporting flammable liquids may be oil companies or tank truck 
carriers that haul a variety of products. 

[7] In most cases, an accidental release of hazmat from a cargo tank 
will require a written report within 30 days of the incident, 
specifically, a Hazardous Material Incident Report, Form DOT F 5800.1. 
This report is also required for damage to the lading system, even 
without a release of hazardous materials. Additionally, immediate 
reporting may be required to the National Response Center, a Coast 
Guard-operated sole national point-of-contact for all oil and chemical 
discharges into the environment in the United States. See 49 C.F.R. 
§171.15-16. Although PHMSA's incident-reporting regulations exempt 
certain specified small releases, such as from the connection or 
disconnection of loading or unloading lines, the PHMSA regulations 
require the reporting of any unintentional release of a hazardous 
material, such as gasoline, and do not otherwise exempt releases below 
a specified minimum quantity. 

[8] PHMSA's incident database is available at [hyperlink, 
https://hazmatonline.phmsa.dot.gov/IncidentReportsSearch/] (accessed 
May 14, 2013).

[9] See, e.g., 54 Fed. Reg. 24982 (June 12, 1989); 55 Fed. Reg. 21035 
(May 22, 1990); 55 Fed. Reg. 37028 (Sept. 7, 1990).

[10] A key concern over addressing this issue at the terminal, which 
industry stakeholders reiterated to us, is that fuel taxes are 
assessed through a metering system once the product is loaded onto a 
truck. To then drain some of the product from the wetlines would 
create an accounting problem, in addition to the issue of whether the 
product could be resold or would have to be disposed of. 

[11] 49 C.F.R. § 173.33(e).

[12] The NTSB considers the practice of transporting flammable liquids 
in wetlines to be an unsafe practice and contends that incidents 
similar to the Yonkers incident are likely to occur in the future. 76 
Fed. Reg. 4847, 4848 (Jan. 27, 2011).

[13] Office of Management and Budget, Regulatory Analysis, OMB 
Circular No. A-4 (Sept. 17, 2003), which implements Executive Order 
12866, Regulatory Planning and Review (Washington, D.C.: Sept. 30, 
1993), requires agencies to assess the costs and benefits of specified 
types of proposed significant regulatory actions to analyze whether 
the expected benefits of the regulation are likely to justify its costs.

[14] According to PHMSA's draft March 2012 regulatory analysis, a 
wetline incident is a reported incident meeting three criteria: 1) 
PHMSA can reasonably determine the incident involved damage or rupture 
to one or more of a cargo tank truck's wetlines; 2) flammable liquid 
was released; and 3) any reported fatalities, injuries, and damages 
were directly attributable to the release of product from the wetline.

[15] PHMSA's initial review to identify wetline incidents was 
conducted by a team of five or six people over the course of about 2 
to 3 months. Although PHMSA did not track resources used to identify 
wetline incidents, officials said the process took about 10 minutes 
per incident reviewed and estimated the total effort between the 
initial review and a later review to identify incidents from 2009-2011 
used about 1,200 staff hours.

[16] In identifying incidents, PHMSA officials said they focused on 
those that would be affected by the proposed rule. For example, PHMSA 
cut 44 incidents from the original list of 172 identified incidents 
reported as involving a liquid release of greater than 50 gallons 
without a fire, under the assumption that since wetlines generally 
hold no more than 50 gallons of liquid, a spill of greater quantity 
would indicate a tank compartment breach or internal valve failure. In 
total, PHMSA cut 59 incidents from its original figure of 172 and 
added 19 new incidents from a review of incidents occurring from 
January 2009 through March 2011. There were less than 20 incidents in 
any given year from 1999-2011 that fall into this group of 132 wetline 
incidents. There were 16 incidents that involved fires and 7 that had 
one or more fatalities, which tended to involve occupants of the 
passenger vehicles. 

[17] The investigated incident occurred in Pilesgrove, New Jersey in 
2009. See NTSB, Hazardous Materials Accident Brief, DCA-09-FZ-001 
(Washington, D.C.: Nov. 12, 2009) and PHMSA, Inspection/Investigation 
Report No. 09323047 (Landisville, N.J.: July 2, 2009). According to 
PHMSA officials, in 2012, the agency initiated a thorough review and 
follow-up audits of all incidents that resulted in death or injury, 
which officials believe will increase the likelihood of identifying 
wetline incidents.

[18] As previously discussed, wetlines hold a total of up to about 50 
gallons of flammable liquid, so PHMSA excludes incidents reporting 
more than this amount that do not involve a fire. 

[19] Industry stakeholders questioned whether any incident involving 
the release of more than 50 gallons of flammable liquid should be 
considered a wetline incident. PHMSA officials said they consider this 
legitimate because fires initiated by a wetline release could spread 
and compromise the main tank.

[20] The January 2011 proposed rule exempts smaller trucks, known as 
straight trucks, that are built with the cargo tank attached to the 
main truck rather than the larger truck-and-trailer style of truck as 
depicted in figure 1 because the truck's structure is assumed to 
provide sufficient protection for the wetlines.

[21] For example, PHMSA officials told us they identified a 2010 
Portsmouth, Ohio, incident as wetline-related, despite the fact that 
its narrative description did not mention loading lines and its 
failure codes were left blank. Instead, PHMSA considered the type of 
vehicle (DOT-406 tank truck) and release amount (20-25 gallons) in the 
incident, which indicated to officials that this was a wetline 
incident since they believed a tank fracture would release much more 
product. Conversely, officials said that some incidents on the 
possibly wetline-related list were ruled out because, for example, 
their database entries indicated that wetlines were impacted but no 
release occurred.

[22] Our review does not suggest that these could possibly be wetline 
incidents; in fact, PHMSA officials pointed out reasons why such 
incidents could have other factors not easily detected in a cursory 
data review that would indicate they are not wetline incidents. As 
discussed in our report, because of limitations with how incidents are 
reported, PHMSA's process for identifying wetline incidents is 
resource-intensive and took months to complete for its regulatory 
analysis. A similar approach to identify wetline incidents was beyond 
our scope. Further, because of concerns about the reliability of 
PHMSA's data, we would not be able to independently identify wetline 
incidents without additional corroborating information.

[23] Under PHMSA regulations, portable tanks are not to transport 
hazardous materials unless they meet additional specifications. 49 
C.F.R. § 173.32. In these instances, as PHMSA officials noted, it is 
likely that carriers misidentified the packaging type.

[24] Officials said the "loading/unloading line" and "inlet valve" 
codes, technically correspond to bottom lines, and carriers can use 
these codes to identify bottom line failure. However, as we discuss in 
the report, carriers use the codes in a minority of cases.

[25] For example, 77 PHMSA-identified wetline incidents indicated the 
"hose" or "piping/fitting" as the part that failed, terms that could 
refer to a range of other equipment, such as the hose a driver would 
use to deliver product to underground tanks at a gas station.

[26] PHMSA officials said they are currently conducting a 6-month 
pilot test where staff are following up with carriers to obtain 
missing or inaccurate failure causes of tank truck hazmat incidents. 
However, according to PHMSA officials, it is not current agency policy 
to follow up on any fields other than fatalities and injuries.PHMSA 
officials said they conducted some follow up activity for all 
fatalities occurring in incidents cited in the draft March 2012 
analysis. 

[27] For example, the narrative for a 2010 Brighton, Colorado, 
incident reported a spill of over 135 gallons, but the field in the 
database indicated that the quantity released was 30 gallons.

[28] See, e.g., Federal Managers Financial Integrity Act of 1982, Pub. 
L. No. 97-255, 96 Stat. 814 (1982), and GAO, Standards for Internal 
Control in the Federal Government, [hyperlink, 
http://www.gao.gov/products/GAO/AIMD-00-21.3.1] (Washington, D.C.: 
November 1999).

[29] Office of Management and Budget, Regulatory Analysis, OMB 
Circular No. A-4 (Sept. 17, 2003). Circular A-4 states that federal 
agencies should assure compliance with OMB's "Guidelines for Ensuring 
and Maximizing the Quality, Objectivity, Utility, and Integrity of 
Information Disseminated by Federal Agencies" in their regulatory 
analyses. Those guidelines state that, among other things, agencies 
"shall adopt a basic standard of quality (including objectivity, 
utility, and integrity) as a performance goal and should take 
appropriate steps to incorporate information quality criteria into 
agency information dissemination practices."

[30] There is an additional 2000 Altoona, Pennsylvania, incident that 
the narrative says resulted in a fatality but that is not marked as 
such in the database fields that track fatalities. According to 
PHMSA's draft 2012 cost-benefit analysis, the fatality in this 
incident is nonhazmat-related. Although this incident does not affect 
the wetline cost-benefit analysis, it is another example of the 
inaccuracy of these data.

[31] A 2001 Green Bay, Wisconsin, incident is recorded in the database 
as having four hazmat-related deaths, but PHMSA officials told us 
these fatalities were later determined to be nonhazmat-related. 
Additionally, a 2004 Taylor, Michigan, incident was originally 
recorded as having a hazmat-related fatality, but PHMSA recently 
changed its determination to a nonhazmat-related death and updated the 
database to reflect this. 

[32] In this case, PHMSA's database showed the fatality in a 2009 
Pilesgrove, New Jersey, wetline incident as nonhazmat-related, despite 
an NTSB investigation that determined the cause of the death to be a 
fire resulting from the release of flammable liquid from a tank 
truck's wetlines. After we discussed this with PHMSA officials, they 
amended the incident data and supporting documentation to state that 
the fatality was hazmat-related. 

[33] The cost categories reportable to PHMSA are material loss 
(estimate of the cost of the product lost), carrier damage, property 
damage, response cost (including police and fire emergency response), 
and remediation (cleanup) cost. Cost fields marked as "$0" in the 
database could indicate the carrier reported it as blank (leaving a 
dash, or no value in the field) or as $0 in the original incident 
reporting form, making it impossible to tell whether the cost was 
unreported or actually $0.

[34] For example, for a 2004 incident in Taylor, Michigan, that 
involved a fire and a fatality, PHMSA officials said they made an 
attempt to confirm cleanup and property damage costs marked as 
"pending," but the carrier did not have this information and PHMSA did 
not make further attempts to follow up on the costs.

[35] PHMSA, A Data Quality Assessment: Evaluating the Major Safety 
Data Programs for Pipeline and Hazardous Materials Safety (Washington, 
D.C.: Nov. 10, 2009). 

[36] Reauthorization of the Department of Transportation's Hazardous 
Materials Safety Program, Hearing before the Subcommittee on 
Railroads, Pipelines and Hazardous Materials of the Committee on 
Transportation and Infrastructure, House of Representatives. 111TH 
Cong. 1 (May 2009) (statement of Cynthia Douglass, Acting Deputy 
Administrator, PHMSA, and Ted Willke, Associate Administrator, PHMSA)

[37] Transportation Research Board of the National Academies, 
Feasibility Study for Highway Hazardous Materials Bulk Package 
Accident Performance Data Collection (Washington, D.C.: 2013).

[38] PHMSA officials told us they are engaged in an ongoing effort to 
improve incident data in response to requirements in MAP-21, which 
they said includes conducting an assessment to review and improve the 
collection, analysis, reporting, and use of data related to accidents 
and incidents involving the transportation of hazmat, including better 
data on tank truck incidents. Officials indicated the efforts would 
not be completed by the publication date of this report. Therefore, we 
were unable to assess how this effort may improve data on wetline 
incidents.

[39] For example, if a carrier indicates on the form that the damages 
from the incident totaled over $500, the electronic reporting form 
will force the entry of a dollar value for at least one specific type 
of damage.

[40] However, PHMSA officials stated the improvements are not 
retroactive to incidents occurring before 2005. 

[41] Federal regulation requires notification to the National Response 
Center in the event of a hazardous material incident that meets 
specific criteria such as involving a fatality, an evacuation of the 
general public, or a shutdown of a transportation artery for 1 hour or 
more. See 49 C.F.R. § 171.15.

[42] The Death and Injury summary is a worksheet for PHMSA internal 
purposes in which staff record information confirmed each time they 
contact carriers. This is part of PHMSA's overall quality control 
process for hazmat incident data. 

[43] Although PHMSA officials said they have always reviewed these 
reports, the agency did not retain them prior to 2012 because of 
concerns about retaining personally identifiable information. More 
recently, the agency decided to begin retaining the reports under lock 
and key whereby interested parties might be provided redacted versions 
or information about the sources PHMSA obtained the reports from. 

[44] The company is a terminal operator, carrier, and marketer. It 
transports and stores petroleum, operates terminals, and sells fuel at 
thousands of retail outlets.

[45] Cargo Tank Concepts told us in June 2013 that a carrier had 
contacted the company about purchasing and installing a manual system 
soon.

[46] Between January 1999 and January 2013, at least six patent 
applications for technologies to address wetline safety risks were 
filed with the U.S. Patent Office. Three of these applications, all 
granted, were for systems to purge wetlines, while two others were for 
systems designed to reduce the amount of liquid spilled in the event 
that a bottom line shears off from the cargo tank.

[47] The extent that the proposed rule would require retrofitting 
depends on how much time the industry would be given to comply, with a 
shorter compliance period requiring more retrofitting than a longer 
one in which existing vehicles could be replaced by new ones that 
already have a purging system installed by the manufacturer.

[48] In assessing the feasibility of the purging system technology, 
PHMSA officials told us they observed the function of a prototype 
model of the purging system that was not installed on an actual cargo 
tank truck. Thus, PHMSA has not assessed the feasibility of the 
nonwelded installation, although officials told us they believed such 
construction techniques were in keeping with other aspects of cargo 
tank truck manufacturing.

[49] The American Petroleum Institute, the American Trucking 
Associations, the Truck Trailer Manufacturers Association, the 
Dangerous Goods Advisory Council, and Baltimore Cargo Tank Services 
referenced the California Air Resources Board's concerns in their 
written comments.

[50] U.S. Department of Transportation, Research and Special Programs 
Administration, Risk/Benefit-Cost Analysis, Prohibiting Hazardous 
Material in External Piping of MC 306/DOT 406 Cargo Tank Motor 
Vehicles: Preliminary Assessment (Washington, D.C.: 1999).

[51] Although the proposed rule states compliance could be achieved by 
installing specified types of bottom damage protection, stakeholders 
told us this option is possibly infeasible and retrofits would be 
inadvisable for tank trucks (see previous table 2). PHMSA's cost-
benefit analysis does not consider costs and benefits of bottom 
protection as a compliance option.

[52] One industry stakeholder, a petroleum marketer and carrier that 
uses the wetline purging system, told us it has no position on the 
proposed regulation.

[53] Office of Management and Budget, Guidelines and Discount Rates 
for Benefit Cost Analysis of Federal Programs, OMB Circular A-94, 
(revised 1992), and Regulatory Analysis, OMB Circular A-4, (Sept. 17, 
2003).

[54] PHMSA included sensitivity analyses to test how costs and 
benefits could differ if certain of the assumptions were changed. In 
the 2011 sensitivity analysis, costs were tested with alternative 
assumptions of a lower purging system installation cost and no 
additional costs related to the weight of the purging unit, 
assumptions which lowered the proposed rule's cost. Costs were also 
tested with an assumption of a greater number of equipped trucks, an 
assumption that would increase cost. Additionally, benefits were 
tested under an alternative assumption of a higher number of avoided 
fatalities and other damages-
-changes that would increase the proposed rule's benefit. The 2012 
analysis included two sensitivity calculations: a "bunching" analysis, 
which assumed carriers would equip their trucks with the technology as 
late as possible to meet the compliance deadline, and an alternative 
assumption about the price of the purging system being lower than 
assumed in the base case, due to the manufacturer's reduction in the 
price of the manual wetline purging system.

[55] PHMSA used the $2,300 cost because it was the price Cargo Tank 
Concepts offered the manual purging system at until the company more 
recently dropped its listed price to $1,380. PHMSA's draft 2012 
analysis acknowledges the price drop and included a sensitivity 
analysis to test the effect of a lower-cost purging system. PHMSA 
officials told us they did the calculations with the higher value to 
be more conservative.

[56] Although there were additional wetline incidents during this 
period with fatalities, those fatalities were attributed to causes 
other than the release of hazmat, such as blunt force trauma, and thus 
are not counted as contributing to the benefits of the proposed 
wetline rule.

[57] For calculating the benefits of proposed rules that seek to 
prevent the loss of life, DOT uses a value of statistical life that 
seeks to represent the benefit of preventing a fatality. Specifically, 
the statistical value of one life is the amount that society is 
willing to pay for a safety improvement that would prevent one 
fatality. PHMSA's draft 2012 analysis used a value of $6.2 million 
that DOT set in 2011. More recently, in 2013, DOT revised the value of 
statistical life to be $9.1 million in 2012 dollars.

[58] In the 2011 analysis, avoided fatalities were about $3.9 million 
of the more than $7.7 million in annual expected consequences and 
would also be about $1 million less per year if calculated with one 
less fatal incident. Figures are in 2009 dollars. The numbers of 
fatalities and fatal incidents did not change between the 2011 and 
2012 versions of the cost-benefit analysis. Because the 2012 analysis 
covered a longer period of time, the benefit per year of avoided 
fatalities was lower in the updated analysis. PHMSA's assumptions 
about the number of passengers per car and the statistical value of a 
life were also slightly different in both analyses.

[59] GAO, Standards for Internal Control in the Federal Government, 
[hyperlink, http://www.gao.gov/products/GAO/AIMD-00-21.3.1] 
(Washington, D.C.: November 1999); and Office of Management and 
Budget, Regulatory Analysis, OMB Circular No. A-4 (Sept. 17, 2003). 

[60] For its January 2011 cost-benefit analysis, PHMSA identified 
wetline incidents occurring between January 1999 and December 2008. 
For its updated draft March 2012 assessment, PHMSA expanded its 
analysis to incidents occurring as of March 2011 and, in doing so, 
added some incidents to its list of wetline incidents but also removed 
some incidents in response to comments from stakeholders that 
questioned whether some of the incidents from the 2011 analysis were 
actually wetline incidents.

[61] During the course of our review, PHMSA officials told us they 
were involved in ongoing efforts to improve their incident data 
pursuant to deficiencies the agency had previously identified and 
hazardous material transportation incident data requirements in MAP-
21. Consequently, we were not able to fully assess how these 
improvement efforts might affect their wetline incident data.

[62] Office of Management and Budget, Guidelines and Discount Rates 
for Benefit Cost Analysis of Federal Programs, OMB Circular A-94, 
(revised 1992), and Regulatory Analysis, OMB Circular A-4, (Sept. 17, 
2003).

[63] In the 20-year compliance scenario, since it assumed tank trucks 
have a useful life of 20 years, only new tank trucks are equipped with 
the wetline purging system, resulting in an equal number of new trucks 
being equipped with the system and all trucks equipped by the end of 
the 20 years.

[64] In cost-benefit analyses, projects (or in this case, different 
compliance-date scenarios) should always be compared over the same 
discounting period since projects with different time frames are not 
directly comparable. Anthony E. Boardman et al., Cost-Benefit 
Analysis, 2ND Ed. (Upper Saddle River, N.J.: Prentice Hall, 2001), p. 
133.

[End of section] 

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