ACMA members and Government Affairs staff participated in a Dec. 7 stakeholders meeting with the Texas Commission on Environmental Quality. TCEQ called the meeting to receive comments on the proposed Standard Permit for Thermoset Resin Operations. The Standard Permit is an administrative short-cut for new plants and modifications seeking to avoid case-by-case permit review. To qualify for the proposed Standard Permit, sources will have to agree to install stacks and powered ventilation equipment, limit hourly emission rate (of styrene and MMA), and operate only during daylight hours. The operating limits in the proposed permit are designed to prevent exceedances of the TCEQ Effects Screening Level for styrene, which has been set by the state at 0.02ppm to avoid nuisance odor problems.
During the Dec. 7 meeting, industry members provided the following comments:
Since the styrene ESL is too low for all but the smallest composite manufacturers, the operating limits in the proposed Standard Permit are also not feasible, and the Standard Permit is not likely to be useful for many sources.
The state has not demonstrated that there is a nuisance odor problem associated with composite plants, which would justify the very low ESL and very restrictive limits in the Standard Permit.
The ventilation and stack requirements in the Standard Permit are too expensive for small and medium-sized companies. A taller stack can cost $250,000, which greatly exceeds the cost of production equipment at many plants. The blowers and ducting to meet the required exhaust rates are also expensive to install and add significant fixed operating costs. The limit on operating hours will prevent growing a company to take advantage of new markets, and limits employment.
The limits in the Standard Permit on acetone usage are too restrictive, and have no obvious public health benefit. The definitions in the Standard Permit for resin and gel coat should exclude materials that do not include styrene or MMA.
The styrene ESL was set arbitrarily, using a laboratory odor threshold determination at the low end of the range of laboratory results. Other, better designed studies would give a more scientific and more feasible limit. TCEQ should also consider the science that shows that laboratory subjects can detect odors at much lower concentrations than people in communities.
TCEQ’s ELS guidelines are intended as a default process that allows the state to quickly establish exposures limits, based on health, welfare (odor) or environmental (vegetative) effects, for hundreds of industrial chemicals. TCEQ should set aside the default ESL for styrene, because the industry has provided relevant scientific data supporting a higher level, because there is no record of odor problems that justifies the current level, and because the current level is not feasible.