Abstract: The present disclosure provides a leak monitoring system and associated method which is being configured to detect plumes of volatile organic compounds (VOC) as an alternative solution to the EPA Method 21, which measures VOC concentrations at the surface of each component. The leak monitoring system is a multi-layered system that includes monitoring performed by sensors that are fixed in place and sensors that are mobile. Each monitoring method is a layer and it complements and augments other layers. All the sensors wirelessly communicate with a central control through a gateway. The control unit further includes a software platform, which analyzes the data provided by the sensors in combination with other informetrics such as meteorological conditions and plant info to both identify the presence of a gas leak and to pinpoint a general location of the gas leak.