One of the most common causes of failure is sometimes referred to as the âcreeping crudâ or âold-ageâ or Biomat failure. Several factors contribute to the development of the biomat; time, wastewater strength, hydraulic load, groundwater saturation, and maintenance are the major ones.
Please exercise caution, and wear a mask over your nose and mouth to reduce the impact on your health. Removing Mold and Mildew growth from the Outside of a Dry Book: 1  If you can perceive growth on your book's cover, you may use a fine brush or very soft cloth to gently brush away the mildew.lease exercise caution, and wear a mask over your nose and mouth to reduce the impact on your health. Removing Mold and Mildew growth from the Outside of a Dry Book: 1  If you can perceive growth on your book's cover, you may use a fine brush or very soft cloth to gently brush away the mildew.
The moisture usually comes from above, seeping through the finish and soaking into the wood, but it can also come from below, if the subfloor is wet. You can kill the mold and get rid of some of the discoloration using wood bleach, but you may have to stain and refinish the floor -- or part of it. There is a big difference between black discoloration that has settled on the surface of your oak flooring and in a discoloration of the wood itself. You can attribute the problem to moisture in both cases, but in the first instance, remediation is fairly straightforward and doesn't involve sanding or refinishing.