### Question
What does annular injection mean?


### Answer
**Annular injection** has the following meaning in *42 U.S.C. § 300h*:

> the reinjection of brines associated with the production of oil or gas between the production and surface casings of a conventional oil or gas producing well

#### Citation:
  - *42 U.S.C. § 300h*
  - Heading: **CHAPTER 6-THE CHILDREN'S BUREAU > SUBCHAPTER XII-SAFETY OF PUBLIC WATER SYSTEMS > Part C-Protection of Underground Sources of Drinking Water**

