National Clothesline

Two years after setting in motion a phase-out of perc in southern California, the South Coast Air Quality Management District (SCAQMD) is continuing to study perc use and emissions while trying to move cleaners to alternative solvents.

To date, SCAQMD remains the only jurisdiction in the United States to invoke a ban on perc, although the rules adopted two years ago allow drycleaners to continue using perc until 2020 provided they meet increasingly stringent equipment requirements. SCAQMD rules apply to an estimated 2,100 cleaners in the counties of Los Angeles, San Bernardino, Orange and Riverside.

As of January 1, 2003, the new rules prohibited new perc plants and said existing plants could no longer add new perc machines. Since July 1 of last year, perc machines that had been converted from vented to no-vent are no longer allowed. By November 1, 2007, all perc machines will be required to have primary and secondary controls and risk-based limits will be defined.

The SCAQMD staff, reporting to its governing board in December on progress of the phase-out, said the number of cleaning plants using non-perc alternatives “has significantly increased” since the phase-out was enacted. The staff report said that over the last two years there have been 235 hydrocarbon installations, 44 GreenEarth installations 31 wetcleaning installations and two liquid carbon dioxide installations mixed with wetcleaning.

The report also noted a statewide decrease in perc machines of about 16 percent compared to a survey taken about 11 years ago. Meanwhile, there has been “an increase of about the same amount of drycleaning machines using alternative technologies,” according to the report.

A grant program to assist drycleaners with implementing alternative technologies has used about $1.4 million of the $2 million that was allocated. There have been 180 applications for financial assistance with hydrocarbon machines, 41 for wetcleaning equipment, nine for GreenEarth equipment and two for liquid carbon dioxide. Grants for GreenEarth have been suspended pending the outcome of a study by Dow Chemical on the potential toxicity of the silcone-based solvent. Results are not expected for another year or two.

Another study still in the works — and which was supposed to have been completed by now — is one undertaken by the SCAQMD staff on perc emissions. SCAQMD’s risk analysis was based in part on its belief that 50 percent of perc used by drycleaners is emitted into the air. Industry representatives contend that the percentage is actually much lower, more on the order of 15 percent.

The emissions issue was much discussed during the debate over the phase-out in 2002, prompting the air board to direct it staff to study the matter. The staff reported in December that sampling of plant emissions was completed in December and the data is being analyzed, so the percentage of perc emitted has not yet been determined.

The outcome of that study could prove crucial to many cleaners, regardless of what type of perc equipment they use. At the higher emissions level estimated by SCAQMD, many cleaners might have trouble meeting the requirements of Rule 1402, which limits the lifetime cancer risk posed by a facility to no more than 25 in one million.

Based on their emission estimate, South Coast officials believe that no more than 20 percent of cleaners can meet the 25 in one million standard. Industry leaders, however, believe that most cleaners using modern equipment should be able to meet the standard.

If the lower industry estimate of emissions proves correct, fewer cleaners would be at risk for more stringent regulations under 1402, which uses a formula based on the amount of perc used, proximity or neighboring businesses or residences and weather patterns.