From Lab to Land: How Murray State is Engineering a Cleaner Future

Turning Environmental Challenges into Actionable Solutions

Environmental Engineering Bioremediation Sustainability

Imagine a silent, invisible threat seeping into the soil and groundwater of an old industrial site. It's a complex cocktail of chemicals, a legacy of past practices that now poses a risk to the ecosystem and community health. How do we tackle such a problem? The answer lies not just in science, but in the applied, hands-on discipline of Environmental Engineering Technology (EET). At Murray State University, this isn't an abstract concept studied in a dusty textbook; it's a dynamic, boots-on-the-ground mission to diagnose, treat, and heal our planet. This is where theory meets the dirt, and students become the next generation of environmental problem-solvers.

The EET Toolbox: Core Concepts for a Sustainable World

At its heart, EET is about application. It takes the principles of chemistry, biology, and civil engineering and turns them into practical solutions for real-world problems. Students at Murray State learn to master several key areas:

Site Assessment & Remediation

The "detective work" of environmental science. This involves investigating contaminated sites, determining the nature and extent of pollution, and designing systems to clean it up.

Water & Wastewater Treatment

Engineering the cycle of water use, from ensuring our drinking water is safe to treating what goes down our drains before it's returned to the environment.

Air Quality Control

Monitoring and designing systems to reduce pollutants from industrial sources, protecting both public health and the atmosphere.

Sustainable Design

Integrating principles of sustainability into projects, focusing on waste reduction, energy efficiency, and green infrastructure.

A central theory in remediation is bioremediation—the use of living microorganisms to digest and break down pollutants, effectively using nature's own tools to clean up messes. It's a powerful, often cost-effective, and natural solution .

A Deep Dive: The Great Vetiver Grass Experiment

To understand how EET students learn to apply these concepts, let's look at a pivotal experiment conducted in their advanced remediation lab: "Phytoremediation of Hydrocarbon-Contaminated Soil Using Vetiver Grass."

The Mission

Can Grass Clean an Oil Spill?

The scenario was a simulated, small-scale soil contamination event, similar to what might happen at a former gas station or a leaking storage tank. The contaminant was diesel fuel, a common pollutant made up of hydrocarbons. The proposed solution? Vetiver grass, a plant known for its deep, dense root system and remarkable tolerance to toxic conditions.

The Method: A Step-by-Step Cleanup

The experiment was designed to be rigorous and provide clear, measurable results.

Soil Preparation

Students collected clean topsoil and divided it into several large, sealed containers to prevent any leakage.

Contamination

They deliberately contaminated the soil in each container with a measured amount of diesel fuel, creating a controlled "pollution event."

Experimental Groups
  • Group A (Vetiver): Planted with vetiver grass seedlings.
  • Group B (Natural Attenuation): Contaminated soil left alone to simulate what happens with no intervention.
  • Group C (Control): Uncontaminated, clean soil.
Monitoring

Over 90 days, the students maintained the containers, watering them equally and monitoring plant health. They took small soil samples at regular intervals (Day 0, 30, 60, and 90) to be analyzed in the lab for Total Petroleum Hydrocarbons (TPH).

Results and Analysis: The Proof is in the Soil

The lab results told a compelling story. The data showed a dramatic decrease in TPH levels in the containers where Vetiver grass was growing compared to the untreated soil.

Table 1: Reduction of Total Petroleum Hydrocarbons (TPH) Over Time
Experimental Group TPH (mg/kg) - Day 0 TPH (mg/kg) - Day 30 TPH (mg/kg) - Day 60 TPH (mg/kg) - Day 90
A: Vetiver Grass 1,500 1,100 650 280
B: Natural Attenuation 1,500 1,450 1,380 1,350
C: Control (Clean Soil) <10 <10 <10 <10

Analysis: The Vetiver group saw an 81% reduction in contaminants, while the untreated soil showed only a 10% reduction, largely due to simple evaporation. This proved that the vetiver grass was actively facilitating the breakdown of the diesel, through a process where its roots released compounds that stimulated hydrocarbon-eating bacteria in the soil .

81%

Reduction in Contaminants

Table 2: Plant Health and Biomass Data (Day 90)
Parameter Vetiver Grass (Group A)
Average Height 82 cm
Root Length 45 cm
Dry Biomass (Shoot) 48 g
Dry Biomass (Root) 32 g

The robust growth, especially the deep root system, demonstrated the plant's tolerance and its physical role in breaking up the soil and increasing oxygen flow, which further aids microbial activity.

Table 3: Key Microbial Counts in Soil (Colony Forming Units per gram)
Experimental Group Heterotrophic Bacteria (Day 0) Hydrocarbon-degrading Bacteria (Day 90)
A: Vetiver Grass 1.5 x 106 8.9 x 107
B: Natural Attenuation 1.5 x 106 2.1 x 106

This final table provides the "smoking gun." The massive increase in specialized, hydrocarbon-degrading bacteria in the Vetiver pots confirms that the plant didn't just survive the pollution—it actively recruited and fostered a microbial cleanup crew.

The Scientist's Toolkit: Essential Reagents and Materials

What does it take to run such an experiment? Here's a look at the essential "toolkit" used by EET students at Murray State.

Vetiver Grass (Chrysopogon zizanioides)

The primary "worker," its deep roots break up soil and exude compounds that stimulate pollutant-degrading microbes.

Diesel Fuel

A real-world hydrocarbon mixture used to simulate soil contamination in a controlled lab setting.

Gas Chromatograph (GC)

A sophisticated analytical instrument used to precisely measure the concentration of petroleum hydrocarbons (TPH) in the soil samples.

Nutrient Broth & Agar Plates

Used to culture and count the populations of bacteria present in the soil, specifically tracking the hydrocarbon-degrading varieties.

Conclusion: Building a Career, One Solution at a Time

The Vetiver grass experiment is more than just a lab assignment; it's a microcosm of the EET program's philosophy. Students aren't just learning that bioremediation works—they are discovering how, why, and under what conditions it works best. They grapple with the same challenges and use the same tools as professionals in the field.

By getting down to business with hands-on, impactful projects, Murray State's EET program ensures its graduates don't just enter the workforce with a diploma. They enter as proven problem-solvers, ready to roll up their sleeves and engineer a healthier, more sustainable world for us all.