On July 17, 2018, EWI Senior Project Manager Bobbilynne Koepke and Drilling Services Manager Daniel Yoakum presented at the Missouri Waste Control Coalition (MWCC) Environmental Conference at Tan-Tar-A Resort at the Lake of the Ozarks. The MWCC Environmental Conference is held annually to help bring together citizens, regulators, business members, and industry professionals to discuss current hot topics in the constantly changing field of waste management.
EWI Presents at MWCC Environmental Conference 2018
Ms. Koepke and Mr. Yoakum gave a presentation entitled “Using Ultraviolet-Induced Fluorescence to Enhance a LCSM.” A copy of the presentation slides is available below. Light Non-Aqueous Phase Liquid (LNAPL), also often referred to as “free product,” generally consists of a fuel such as gasoline or diesel that can become trapped in the soil after a petroleum release. LNAPL can pose a variety of environmental risks, such as vapors getting into a nearby building, free products dissolving into drinking water sources, and flammability/explosive concerns.
Consultants use all of the data they have gathered about a site to compose a LNAPL Conceptual Site Model (LCSM) which helps “tell the story” of a site and gives a more three-dimensional picture of what’s going on to help guide decision-making. As part of this LCSM, it is important to fully understand where the LNAPL is and how much is there, so that the consultant can determine the most appropriate remedial technology for removing the LNAPL to the extent practicable. To some extent, this can be done with soil borings and monitoring wells, but this data is limited and can take a long time over several iterations of site visits to collect.
Upon exposure to ultraviolet (UV) light, polynuclear aromatic hydrocarbons (PAHs) in LNAPL fluoresce in the violet-to-green spectrum. Currently, there are two types of tools that can log this fluorescence. Laser-induced fluorescence (LIF) or ultra violet optical sensing tool (UVOST) use a laser in the UV range, while Geoprobe’s Optical Image Profiler (OIP) uses a UV light and includes an optical camera that can snap photos of the subsurface. These tools are connected to direct push drilling rods and advanced through the soil, while data is transmitted via cable back to a computer where the data and images can be reviewed in real time. This method collects thousands of data points per boring and can be used to develop detailed 3D models. This type of high-resolution site characterization allows for better decision-making with greater certainty, which allows for faster and more efficient site cleanup.
In addition to a discussion of the technology, Ms. Koepke and Mr. Yoakum’s presentation at the MWCC Environmental Conference provided two brief case studies of sites where these two tools have been used. One site is a large truck stop in northeast Missouri that has had ongoing investigation, while the other shows how the OIP tooling was used at a power plant to find the source of a diesel leak after both excavation and a pipe inspection camera had been unsuccessful.
If you have a site with free product and need assistance, contact Environmental Works, Inc. EWI has cleaned up hundreds of petroleum sites throughout the Midwest. EWI has Missouri offices in Kansas City, Springfield, and St. Louis; along with offices in Decatur, Illinois; Tulsa, Oklahoma; and Springdale, Arkansas, with over 50 qualified scientists and geologists. Our staff has a combined experience of more than 100 years specifically on petroleum cleanup sites.
In addition to our consulting services, EWI is unique because of our in-house resources for field services, which include 75 trained field technicians and equipment operators, as well as heavy equipment for spill response, excavations, and tank removals, and a full range of drilling services. EWI also owns the OIP tooling and software for LNAPL investigations. EWI’s tank clients include everyone from private individuals with one tank to large regional and national petroleum marketers.
To view the slides of the presentation “Using Ultraviolet Induced Fluorescence to Enhance a LCSM,” please click here.