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.
Tip: Air Out Old Books. To get a musty odor out of old books, place the books outdoors in the sun and frequently fan out the pages so that the air can reach them. Brush off any mildew or mold. If the pages are damp, sprinkle cornstarch between them and brush it off after a few hours.