LUS has been using land application (landfarming) for the beneficial reuse of its biosolids for approximately 50 years. There are five landfarming sites permitted to LUS in Lafayette Parish. These sites were brought to the attention of LUS by farmers who wanted the fertilizer benefit of the program. These farmers would have to purchase commercial fertilizer if not for this free program.
Through the years, LUS has received a number of awards related to its landfarming program and has an excellent reputation with the EPA and DEQ concerning this program. LUS believes in the environmental benefit from the landfarming program, and is committed to providing a high level of quality in this program.
Here are some questions and answers about this beneficial program:
What is landfarming?
Wastewater is treated at LUS' four wastewater treatment plants. The treatment process uses naturally-occurring microorganisms to break down components in the wastewater to a level suitable for discharge. The microorganisms result in an accumulation of solids referred to as sludge or biosolids. These biosolids are not discharged with the treated water. In landfarming, the biosolids are applied to a farm pasture one section at a time and are utilized as fertilizer for hay production and cattle grazing.
What are the benefits of the program?
Some of the benefits to landfarming include:
- Increased water infiltration into the soil and soil moisture-holding capacity (reducing runoff and flooding)
- Reduced soil compaction (increases the amount of pore space available for root growth and entry of water into the soil)
- Increased ability of the soil to retain and provide nutrients
- Reduced soil acidification
- An energy source (carbon) for beneficial microorganisms
Are there alternatives to landfarming?
Yes. There are three different ways to dispose of sludge: landfill, incineration and land application (landfarming). However, land application is the only option that seeks to beneficially reuse the organic matter and plant nutrients in the biosolids.
How is the landfarming program monitored?
The Industrial Pretreatment section of LUS closely monitors industrial discharges ensuring compliance with permit limits for heavy metals. The Environmental Protection Agency (EPA) regulates all landfarming programs throughout the United States. Annually, results of testing compiled by the Landfarming section are sent to the EPA for review. Copies of all analytical testing are sent to the Louisiana Department of Environmental Quality (DEQ) who further regulates all landfarming within the state of Louisiana. They also establish certain limitations such as specific application distances from homes, water wells, and surface water; training of individuals responsible for the programs; and restricting crop harvest and grazing for a specific time after application.