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.
1 Mix 1 cup of borax with 1 gallon (3.8 L) of water. 2  Dip a scrub brush in the solution and use it to scrub away the black mold. 3  Wipe the area clean of mold. 4  Don't rinse the area, since the borax will prevent the spores from growing again. Mix 1 cup of bleach and 1 gallon (3.8 L) of water. 2  Use a spray bottle or a bucket and sponge to apply the bleach mixture to the area with black mold. 3  Let the bleach sit on the mold for an hour.