RSPA publishes NPRM to ban wetlines
Jan 1, 2005 12:00 PM
AS 2004 drew to a close, the Research and Special Programs Administration (RSPA) launched a new effort to eliminate wetlines on tank trailers. Industry wasted no time in responding to what some consider to be a high-cost regulatory initiative with minimal benefit.
Published as a notice of proposed rulemaking (NPRM) under HM-213B, RSPA's regulatory initiative would limit flammable liquid to one liter (.26 gallon) or less in each exposed product pipe on a tank trailer after unloading. The NPRM was published in the December 30, 2004, Federal Register, and RSPA wants comments submitted no later than February 8.
National Tank Truck Carriers has filed for a 180-day extension in the comment period. “We've known for awhile that this rule was coming, but we still need time to study the NPRM and develop a response that reflects the views of our members,” said Cliff Harvison, NTTC president. “This rulemaking will have significant financial impact on the small businesses that constitute a vast majority of the petroleum transportation industry. We will work with them to try to analyze alternatives to the high-cost options provided in the rulemaking.
“We believe that the proposal's data on purging-equipment purchase and installation costs, number of true “wetline” accidents that have occurred, number of trailers impacted, and compliance costs are wrong and will need substantial correction after a detailed review by our industry. We have already determined that several statements presented as ‘fact’ in the NPRM are erroneous.”
The wetlines proposed rule would apply to both new tank trailers and those already in service. Tankwagons are exempted in the NPRM, but RSPA is asking for comments on this exception.
The NPRM is written as a performance standard, which means RSPA doesn't care how the wetlines issue is resolved. However, the NPRM clearly shows that the agency has some strong preferences, and RSPA approval is mandatory for any alternative systems.
RSPA defines the preferred technology as “an on-board system that evacuates the wetlines by forcing the lading out of the product piping and into the cargo tank body. After loading is complete and the main cargo tank valves are closed, the system introduces compressed air from an auxiliary tank into the product piping under low pressure at a low flow rate. Lading in the product piping is displaced by air and flows through separate purging lines into the cargo tank body. The purging process is controlled automatically and lasts approximately six minutes. The system is also capable of detecting and automatically purging any leakage of product through the cargo tank's internal shutoff valve into the product piping, thereby eliminating a potential wetline condition during transportation.”
The docket highlights two basic types of systems, referred to as manual and automatic, and this played a critical role in the government's cost-benefit analysis. The manual system is similar in design to the automatic system, minus optical sensors, solenoids, and LED displays. The automatic system also requires welding, while the manual system does not. To cost-justify the rule, RSPA used an estimated $2,150 tank retrofit price (what it would cost to install the non-welded manual system).
By using the non-welded system as a baseline, RSPA ignored a number of cost and risk factors that could significantly reduce the benefit of a wetlines elimination system. For instance, RSPA ignored the risk to workers in tank repair shops who will make many of the wetlines modifications that do require welding.
RSPA wants the regulation to be in force for new tank trailers two years after the effective date of the final rule (probably sometime in 2005). Retrofits for existing tank trailers would have to be completed no later than five years after the two-year deferral for new cargo tanks.
An existing tank trailer would have to be brought into conformance on or before the date of the vehicle's first scheduled pressure retest after the deferral period expires. This means a tank trailer owner would be able to wait as long as seven years before installing a wetlines purging system.
© 2013 Penton Media Inc.