### Question
How does the law define aggressive biological treatment facility?


### Answer
Under *42 U.S.C. § 6925*, **aggressive biological treatment facility** is defined as:

> a system of surface impoundments in which the initial impoundment of the secondary treatment segment of the facility utilizes intense mechanical aeration to enhance biological activity to degrade waste water pollutants and


(i) the hydraulic retention time in such initial impoundment is no longer than 5 days under normal operating conditions, on an annual average basis

#### Citation:
  - *42 U.S.C. § 6925*
  - Heading: **CHAPTER 82-SOLID WASTE DISPOSAL > SUBCHAPTER III-HAZARDOUS WASTE MANAGEMENT**

