Landscaping

Silt and sediment are fine-grained soil particles readily carried in surface run-off and may migrate directly or indirectly to surface waters. Improper erosion control can lead to surface run-off, which can impair the functionality of stormwater drainage systems and catch basins, severely damage water quality, cause ecological damage to streams, rivers, and aquatic systems, and damage to adjacent property. Control of silts and sediments is required under the Clean Water Act. Contractors may face regulatory action such as cleanup orders, fines, and penalties from federal, state, or local regulators.

Site application of fertilizers may result in ground or surface water contamination or health impairment, particularly if nitrification inhibitors are present, such as nitrapyrin, dicyandiamide, or carbamoyl methylpyrazole. Over-application, shallow water tables, and stormwater run-off may cause this. Phosphorus, a main ingredient in synthetic fertilizers, encourages the growth of algae, which depletes oxygen out of lakes, rivers, and streams and can harm aquatic life or lead to the growth of toxic blue-green algae.

Leaks, spills, or over-application of herbicides and pesticides can contaminate soil, surface, or groundwater. Applications made before heavy rains or on saturated soils can also contribute to contaminated stormwater run-off. Pesticides and herbicides contain toxic materials that pose health risks to humans, animals, aquatic organisms, and plants. If applied to hard surfaces, such as concrete, there is nothing to absorb the pesticide, and it is even more likely to cause contaminated run-off. Vegetative wastes with over-applied herbicides or insecticides or retaining persistent chemicals will also likely contaminate a disposal site.

Pesticide and fertilizer drift is an insidious threat to human health, wildlife, and ecosystems in and around areas where harsh chemicals are used to treat lawns. Children are especially vulnerable to these airborne pesticides, and when pesticides are sprayed, they can drift and settle on playgrounds, porches, laundry, toys, pools, furniture, and more.

Storage at any owned/leased operational facility of pesticides, fertilizers, and automotive fluids for work site equipment and vehicles carries environmental exposure. Spills, improper storage containment, and exposure to rainfall can cause chemicals to run-off and contaminate surface water, groundwater, and soils, resulting in cleanup and potential natural resource damage claims. Storage of concentrated ammonia-based fertilizers may react with other stored incompatible materials (e.g., lime, urea, nitrates, and sulfur) if leaked or spilled, resulting in a fire or the emitting of air pollutants.

During transportation or loading and unloading, an accident or container breach could cause a leak or spill of pesticides, fertilizers, or fluids from powered equipment and lead to environmental liability. Dry particulates that are loose can also blow off during transport if they are not properly covered or secured, which can cause air contamination.

Pesticides, fertilizers, and automotive fluids can fall under hazardous waste and require special disposal procedures. Pesticide waste can include rinse material from containers and spray equipment, surplus spray solutions, and excess pesticides. Improper handling and disposal can lead to contamination of soil and ground and surface water causing cleanup and third-party liability. Several federal and state laws regulate pesticide waste disposal, and improper disposal can also result in fines for the contractor.

Improper erosion control or installation of irrigation and drainage systems, retaining walls, and trenches can lead to water run-off that causes moisture intrusion conditions and mold growth.