On May 16, 2003, EPA promulgated national emission standards for hazardous air pollutants (NESHAP) for new and existing sources at brick and structural clay products (BSCP) manufacturing facilities (the final rule). Subsequently, the Administrator received a petition for reconsideration of the final rule. On April 22, 2005, EPA announced its reconsideration of one issue arising from the final rule. Specifically, we (EPA) requested public comment on our decision to base the maximum achievable control technology (MACT) requirements for certain tunnel kilns on dry limestone adsorption technology. As a result of this reconsideration process, we have concluded that the MACT floors and standards determined at promulgation are correct, and no changes to the final rule are warranted. We, therefore, are taking no amendatory action with respect to these requirements.