Abstract: A system for monitoring the concentration of volatile material dissolved in a liquid such as a wastestream comprises a vessel including a liquid space containing the liquid and a head space containing gas disposed above the surface of the liquid. In a preferred embodiment, a liquid inlet is disposed in communication with the head space for injecting a stream of the liquid into the vessel at a sufficient velocity to creates bubbles and turbulence in the liquid, thereby enhancing the transfer of the volatile material from the liquid phase to the gas phase. A liquid outlet including a liquid outlet port formed in the vessel and a liquid discharge conduit disposed in communication with the liquid outlet port discharges the liquid from the vessel. An air pump and an exit conduit remove a portion of the gas contained in the head space from the vessel.