When effluent is land applied for irrigation, which tests are required to be conducted?

When effluent is applied to land for irrigation, it is important to monitor its quality to ensure that it does not negatively impact the soil, crops, or the overall environment. The required tests include CBOD (Carbonaceous Biochemical Oxygen Demand), TSS (Total Suspended Solids), pH, and dissolved solids.

CBOD is important because it measures the organic matter in the effluent that can deplete dissolved oxygen levels in receiving environments, which is critical for aquatic life. High levels of organic material can also affect the soil's health and the growth of crops. TSS indicates the concentration of particulate matter, which can lead to clogging of soils and irrigation systems if levels are too high.

pH is a key indicator of the acidity or alkalinity of the effluent, influencing nutrient availability and microbial activity in the soil. Lastly, dissolved solids provide insight into the concentration of salts, which, if excessive, can cause soil salinity issues affecting plant growth and soil structure.

Collectively, these tests provide a comprehensive understanding of the effluent's potential effects when used for irrigation and are critical for ensuring safe and effective land application practices.