1. (N) Verify material of construction.2. (N) Tank materials are confirmed to safely holding contents at operating conditions (recommended thickness for plastic tanks at least 1/2"", 5/8"" preferred).3. (N) Stainless steel tanks have adequate thickness and welded joints are not leaking.4. (N) Tanks are adequately reinforced to avoid deformation. 5. (N) Adequate secondary containment is in place.6. (N) Corrosion has not compromised tank structures."