Workers removed any remaining corrosion, grout, and other contaminants with hand chisels and power-operated wire brushes.
Chad Randl
2002
<a rel="nofollow" class="external free" href="http://www.nps.gov/hps/tps/technotes/ptn47/repair_replacement.htm">http://www.nps.gov/hps/tps/technotes/ptn47/repair_replacement.htm</a>