Nonpoint source air pollution affects air quality from sources such as smokestacks or car tailpipes. Construction of the smokestacks continued, but construction of the boilers was halted. They were known as "four-pipers" or "four-stackers" because they had four smokestacks (funnels). In 2005 Cornyn voted against including oil and gas smokestacks in mercury regulations. The Parkway plant included landmark smokestacks spelling out "Overland" in bricks. Another proposal requiring hinges on high steamboat smokestacks also initially failed. The forward launchers were located between the smokestacks. The seven baseball bats featured on both smokestacks symbolize the #14 of Pete Rose. The final design had a flush deck and four smokestacks.