1. Condenser tube sheets suffer from virtually all forms of attack, galvanic corrosion, chemical corrosion, crevice corrosion, microbiologically induced corrosion, and erosion

2. Biodegradation is the mostly microbiologically mediated natural process that continually recycles biologically essential elements within the Earth’s biogeochemical cycles. Biodegradation processes usually are catalyzed by enzymes that are arranged in pathways that convert chemicals via series of intermediates into end products.