THE NATIONAL Tank Truck Carriers has filed “strong” opposition to a federal proposal that would mandate wetline purging systems on newly-manufactured and existing tank trailers transporting flammable liquids.
NTTC filed its comments with the Pipeline and Hazardous Materials Safety Administration (PHMSA), criticizing the agency's estimate of wetline accidents and societal costs, and describing some of the estimates as “grossly exaggerated.”
NTTC said the agency relied on data from 190 accidents occurring over a 12-year period that reportedly involved wetlines. However, NTTC's analysis of the data found that only 70 of the 190 accidents included spills that were inarguably related to wetlines. The other 120 accidents either clearly were not based on the wetlines, or at least are inconclusive.
“As a result, PHMSA's estimates for societal gains related to reductions in product losses, fatalities, injuries, lost product value, and cleanup costs that have resulted from wetlines failures are each grossly exaggerated,” NTTC said.
In addition, the agency failed to use readily-available in-house information to determine vehicle population potentially impacted by the proposal.
PHMSA relied both on an editorial from a trade magazine, as well as calculations based on annual nationwide volumes of gasoline production, to determine the universe of cargo tanks that will be affected by the rulemaking. However, PHMSA had several other more reliable sources for information readily available that it should have explored, NTTC argued.
The association said one source is PHMSA's own hazardous materials registration database, which identifies carriers that transport hazardous materials in cargo tank motor vehicles. Another source is the Federal Motor Carrier Safety Administration's (FMCSA) registration database of “Motor Carrier Identification Numbers.” Another is FMCSA's Hazmat Safety and Security Field Operations Test final report dated August 31, 2004, which drew upon the Motor Carrier Management Information System (MCMIS).
“If the administrator had used these readily available sources, it would have estimated the number of cargo tank motor vehicles to be significantly higher than the 15,000 trailers that it claims will be affected,” NTTC said. “Likewise, the estimated cost associated with compliance would have been significantly higher than PHMSA has suggested.”
NTTC said it believes that the number of cargo tank motor vehicles in service among members of the NTTC, the Petroleum Marketers Association of America (PMAA), and the America Petroleum Institute (API) is well in excess of 26,000 trailers.
PHMSA significantly underestimated the costs of retrofit and has ignored other costs attendant to the proposal, according to NTTC.
Contradicting PHMSA's estimate that the total cost of retrofitting a four-compartment tank trailer will be $2,160, NTTC has determined that the typical retrofit will cost closer to $3,180 even before other ancillary costs are incurred, such as additional air tanks and lines, possible modifications to the internal valves, recalibration of each tank compartment, and a tie-in with each compartment's overfill protection system.
By also claiming that retrofitting can occur while a trailer is undergoing its required five-year pressure retest, PHMSA greatly underestimates the period of time that each trailer will have to be out of service. The retrofit cannot occur until after the pressure retest is complete and will take an estimated 30 hours longer than PHMSA has acknowledged.
The agency also has grossly underestimated training costs to achieve compliance with the proposed rulemaking, as well as costs related to maintenance, NTTC said.
PHMSA failed to deal with the reality that virtually all so-called wetlines accidents involved damage to tank vehicle structures other than (or in addition to) the product piping, NTTC added.
An NTTC study demonstrates that even in the case of an accident occurring at a very low impact speed, it is highly probable a vehicle will strike the shell of the cargo tank at either the hood line or below the roof line of the impacting vehicle, rather than merely impacting the wetlines.
The agency's proposal would apply to a wide range of products, other than gasoline, having physical characteristics that may inhibit or prohibit line purging systems' capabilities.
“PHMSA has failed to demonstrate that it has considered whether the product purging system can safely be operated on a chemical tank trailer transporting the broad range of non-petroleum flammable products,” NTTC said. “These products can bear physical characteristics potentially capable of damaging any product purging system, such as corrosivity or viscosity. Further, these tank trailers are routinely cleaned with highly caustic cleaning solutions, which could also potentially damage the product purging device.”
The agency failed to propose any methodology of, or procedures for, enforcement, NTTC charged. Especially as applies to the manual system that PHMSA proposes to require, roadside inspecting personnel have no means of ascertaining whether the product piping contains more than the one liter permissible under PHSMA's proposal.
In the event that a device such as a sight glass will have to be installed to enable roadside personnel to view the amount present in the product piping, NTTC contends both that the sight glass is an unreliable indicator and that PHMSA has again grossly underestimated the cost of compliance due to failure to include costs associated with installing sight glasses on each affected compartment.
PHSMA has failed to account for the costs of supplementing the air supply system on both new and existing cargo tanks, according to NTTC.
“A cargo tank manufacturer has estimated that the proposed product purging system would require a 30% greater than normal demand on the air supply system,” NTTC said. “In order to achieve the additional 30 percent of air supply needed, it appears likely that each trailer will have to be retrofitted with an additional air supply reservoir that PHMSA has not considered in calculating compliance costs.”
PHMSA has failed to provide comprehensive background materials in the federal docket upon which comments may rely to rebut or respond to various assertions made in the proposal.
“Although the agency has publicly represented that both manual and automatic product purging devices will be available to retrofit onto trailers, there is practically no information in the public venue relevant to the manual system,” NTTC said. “All pertinent information concerning the efficacy of the product purging device relates to the automatic system. However, importantly, when estimating compliance costs, PHMSA has relied on the manual system as the low-cost alternative that carriers are likely to install.”
NTTC addressed the law of unintended consequences. “Despite PHMSA's claim that the purging system will be 100% effective, NTTC contends that PHMSA has failed to consider certain very realistic possibilities,” the association said. “For one thing, such a system may fail if ice accumulates in the low points of piping and unloading valves, as often occurs in northern climates during winter.
“For another, NTTC fears for the likelihood that an impacting vehicle will tear the product return lines out, which will in turn either tear the attaching assembly out of the tank belly or damage the emergency valve. Should such occur, a substantial product loss will surely result.”
Another point of concern is lack of a proven way to check for the presence of flammable product or vapors in the purge system itself. Nor is there a way to purge the product return tubing. Flammables trapped in the purge system can create an explosive atmosphere.
“We are hopeful that most specialists in cargo tank repairs will be aware of this potential hazard and take actions to eliminate it,” NTTC said. “However, these same vehicles are often serviced at facilities where welding or other hot work is done on chassis, undercarriages, brakes, by personnel who may not realize the dangers involved because they are not specifically working on the tank.”
Additionally, NTTC alerted the agency to concerns related to loading. Some vendor literature states that carriers and loading racks will not suffer losses in productivity because the purging process will only take approximately six minutes to complete while a driver addresses paperwork requirements away from the vehicle, NTTC notes that 49 CFR 177.834 (i) requires require the driver to remain within 25 feet of the cargo tank and have an unobstructed view of both the tank and the loading/unloading lines. Therefore, because the line purging will be part of the loading process, the driver will not be able to leave the scene as suggested without violating the hazardous materials regulation, which means the six minutes purging time equates to lost productivity.
“This loading process is replicated several times each day, day-after-day, by thousands of drivers,” NTTC pointed out. “PHMSA has failed to consider this lost productivity compliance cost when performing its regulatory assessment.”
Finally, there is for the possibility that overfill protection systems for each compartment on a considerable number of trailers will have to be recalibrated and reconfigured to ensure the exact gallon capacity of each compartment is achieved for billing and tax purposes.