Soil, Solid Waste & Groundwater Testing
Soil and groundwater testing are essential practices for monitoring industrial discharges and ensuring they do not negatively impact the environment or pose risks to human health. Various technical articles, protocols, and approved analytical methods are available to guide the testing and management of solid waste, particularly for the detection of heavy metals and other environmental pollutants. These methods play a critical role in safeguarding natural resources and maintaining environmental safety standards.
Overview
Solid Waste and Its Impact on Soil and Groundwater
Solid waste is the refuse generated from human activities during industrial, commercial, mining, and agricultural operations. With the increase in population and industrial activities, solid waste must be appropriately managed and contained to avoid adverse impacts on the environment and human health. Traditional landfill sites are commonly used for solid waste management due to their simplicity, large handling capacity, and minimal operating costs. However, improperly maintained landfills with poor leachate collection systems can contaminate soil, surface, and groundwater. Solid waste can alter soil chemistry and cause significant environmental harm by producing leachate and biogas. Common contaminants in solid waste leachate include chromium, dioxins, hydrocarbons, organochlorines, PAH, PCB, pesticides, radionuclides, TPH, VOC, POPs, and pathogens. Therefore, a proper leachate monitoring program is crucial for safety and risk assessment.
Soil and Groundwater Testing
Soil and groundwater testing are critical components of leachate monitoring programs and vital for site investigations or environmental risk assessments. The complexity and variability of soil and groundwater matrices make accurate measurement challenging. The United States Environmental Protection Agency (USEPA) recommends the Toxicity Characteristic Leaching Procedure (TCLP) to determine hazardous elements in waste. TCLP simulates contaminant leaching in a landfill environment over time, assessing the mobility of organic and inorganic contaminants (such as metals, pesticides, herbicides, and solvents) in liquid, solid, and multiphasic wastes.
Leaching Environmental Assessment Framework (LEAF)
The Leaching Environmental Assessment Framework (LEAF) is an alternative evaluation system used to identify and accurately describe the release of inorganic, semi-volatile organic, and non-volatile organic constituents of potential concern (COPCs) in solid materials. LEAF provides a customizable framework for evaluating leaching characteristics under a variety of conditions for different solid materials in contact with groundwater or surface water.
Soil and Groundwater Testing Techniques
Regulatory agencies, including the USEPA, require the use of standardized methods for soil and groundwater testing. These tests assess various physicochemical properties, including total dissolved solids, pH, water hardness, cations, anions, organic matter, total carbon, nitrate, ammonium, and heavy metals. Common analytical techniques for soil and groundwater testing include conductivity, titrimetry, gravimetry, fluorimetry, atomic absorption spectroscopy (AAS), high-performance liquid chromatography (HPLC), gas chromatography, ICP-MS, LC-MS, and GC-MS.