North Carolina Panel Surveys Alternatives

Perc use in drycleaning has dropped dramatically in the past 15 years, but further reductions are possible and should be encouraged by the state. So concluded a panel that studied drycleaning processes and alternatives under the direction of the North Carolina Department of Environment Resources.

At the same time, the panel’s report noted that the North Carolina Occupational and Environmental Epidemiology Branch (OEEB) determined “that there is no credible evidence to associate perc as used in the drycleaning industry with cancer in humans.” The OEEB had been asked to review human health and environmental risk as part of the overall study which was ordered last year by the North Carolina general assembly.

Better equipment and operating procedures have solved many of the pollution problems the industry had in the past, the panel concluded and neither perc nor petroleum, as they are currently used and regulated in drycleaning industry, pose a significant health risk to the general population.”

“In view of the large reductions in both perc and Class II petroleum solvent usages, and with both of these solvents not being classified as known human carcinogens, the question arises as to whether additional pressures or incentives should be applied to further reduce and/or eliminate either one or both of these solvents,” the panel’s report said.

The panel recommended financial incentives instead of new laws or rules to help cleaners continue reducing their usage of traditional solvents or implement newer cleaning processes in their plants. Current requirements should remain in place, however, the panel advised.

The 19-member panel began its year-long study in January, 2001 with the charge to evaluate alternative drycleaning processes, identify historical trends, evaluate benefits and costs of alternative processes and evaluate the feasibility of implementing new processes and equipment. The study group was also asked to present recommendations and legislative proposals.

The panel was made up primarily of members of the drycleaning industry and also included state environmental and small business officials and representatives of the Sierra Club and the Blue Ridge Environmental Defense League.

“The study group tried to look at all aspects of each process in considerable detail and to fully evaluate each of them in a critical manner, said Bill Albright, an environmental engineer with the North Carolina Department of Environmental and Natural Resources who was the team leader of the study group.

“Most of the members (of the study group) openly and freely contributed their experience and expertise to this study and conducted themselves in a constructive manner,” Albright wrote in a cover letter that accompanies the final 89-page report. “Many aspects of the industry were debated in depth, and the group usually reached a consensus.”

The panel found that in North Carolina, like the rest of the country, perc and Class II petroleum solvents are the most widely used by drycleaners but that other processes are in place, too. North Carolina was home to the first liquid carbon dioxide cleaning plant in the nation and other processes, such as cyclic siloxanes (GreenEarth and Pure Green) and Class IIIA petroleum solvents are in use in North Carolina cleaning plants. The use of wetcleaning is increasing, too, the panel found.

Perc efficiency has increased dramatically over the past 15 years and most of the transfer-type perc equipment had been removed from North Carolina cleaning plants by 1997, the panel said. Average mileage in North Carolina perc plants was 272 pounds cleaned per gallon of perc, the study said, but that could be improved by upgrading all equipment to fourth-generation, which could yield 600 pounds per gallon.

Usage of petroleum solvents has been reduced, too, by the installation of solvent recovery dryers and vacuum stills. There is potential for further reduction in usage in this area, too, the report said.

In addition to more efficient equipment, additional operator training and more use of wetcleaning could also bring about less solvent use. “While considerably more clothes could be wetcleaned, wetcleaning is not a potential complete replacement for any of the current or alternative processes,” the report concluded.

Of the alternative processes, the study group concluded that “the cyclic siloxane process plus wetcleaning appears to be a feasible, innovative and complete alternative.”

“This process uses a Class IIIA solvent in essentially the same type of equipment used in dry-to-dry petroleum cleaning It seems to clean all types of garments acceptably and the manufacturers continue to work on improving the current solvent and detergent mixtures,” the report said.

Of liquid carbon dioxide, the study said it “appears to be a feasible, innovative alternative, but apparently is not a complete alternative at this time as some of the current operations have found it necessary to add solvent machines or outsource some clothes in order to handle all fabrics.”

In comparing cyclic siloxane with carbon dioxide, the panel noted that the former not only has lower initial start-up costs but also gives the user a fall-back position in that if the new process doesn’t work out, the equipment could be converted to a petroleum solvent; no such fall-back is available with carbon dioxide.

Another downside to both carbon dioxide and cyclic siloxanes — as well as Class IIIA petroleum — was raised by the report.

“The solvent detergent systems in the new processes… are not hazardous materials according EPA but are hazardous materials according to OSHA,” the DENR’s Albright noted in his cover letter to the report. “This raises the question of whether they are eligible for the 20 percent tax credit for purchases of new technologies as offered by HB 1583.”

The OSHA hazardous materials classification rises from the flashpoints — 140°F plus with Class IIIA petroleum solvents; 170°F for cyclic siloxanes and 177°F for a hydrocarbon detergent mixture used in one of the carbon dioxide processes.

“All of the new Class IIIA solvents are more acceptable environmentally with their higher flashpoints, but all of these materials are still significant fire hazards,” the report noted.

In its recommendations to the general assembly, the panel said legislation should be adopted to provide financial aid to drycleaners for the acquisition and installation of equipment to further reduce the usage of current solvents and help in converting to new processes. The aid should be in the form of grants, low-interest guaranteed loans or tax credits.