Resources

Date: September 2011

Environmental Protection at Construction Sites

Both Environmental Protection Agency (EPA) and the Louisiana Department of Environmental Quality (LDEQ) seek, through regulation, to limit the pollutants that are discharged from construction sites. Some recent developments may impact your current or future operations at these types of sites.

Stormwater Management

EPA tightened its regulation of storm water discharges from construction sites. These regulations, formally called effluent limitations guidelines, or ELGs, are essentially more detailed and elaborate best management practices (BMPs) to be used during construction activities. By using these more stringent and detailed BMPs, EPA hopes to decrease the amount of pollutants, such as oil and grease or sediments, in the storm water that leaves a construction site.

As you are probably aware, the LDEQ’s level of regulation over storm water discharges from construction activities increases based on the size of the construction site. For sites less than one acre, no permit is required. For sites between one acre but less than five acres, a general permit (LAR200000) automatically applies but you must prepare and implement a Stormwater Pollution Prevention Plan (SWPPP) and follow the terms of the general permit. For sites greater than five acres, a Notice of Intent must be submitted to obtain coverage under a more stringent general permit (LAR100000), you must prepare and implement a SWPPP, and follow the terms of the general permit.

Generally, the SWPPP is used to describe BMPs that will be implemented to control and reduce the pollutants in storm water run-off from the construction site. Under the rules, the erosion and sediment controls to be used during construction are spelled out.

At a minimum, the erosion and sediment controls must be designed, installed and maintained to control stormwater volume and velocity within the site to minimize soil erosion; control stormwater discharges, including both peak flowrates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and streambank erosion; minimize the amount of soil exposed during construction activity; minimize the disturbance of steep slopes; provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal and maximize stormwater infiltration, unless infeasible; minimize soil compaction; and, unless infeasible, preserve topsoil. Additionally, the controls must address factors such as the amount, frequency, intensity and duration of precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of soil particle sizes expected to be present on the site.

Pollutants from equipment used on-site must also be addressed. Effective pollution prevention measures to minimize the discharge of pollutants must be designed, installed, and maintained. At a minimum, such measures must minimize the discharge of pollutants from equipment and vehicle washing, wheel wash water, and other wash waters. Wash waters must be treated in a sediment basin or alternative control that provides equivalent or better treatment prior to discharge. Additionally, the controls must minimize the exposure of building materials, building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste and other materials present on the site to precipitation and to stormwater; and minimize the discharge of pollutants from spills and leaks and implement chemical spill and leak prevention and response procedures.

These or similar controls may already be included within your current SWPPP. However, the SWPPP should be reviewed to ensure conformity with these new guidelines.

Spill Prevention Capacity

LDEQ has recently amended its Spill Prevention and Control Rule (SPC Rule), which is similar to the federal Spill Prevention Countermeasures and Control (SPCC) Rule. An SPC Plan is designed to prevent spills or releases from entering surface water. As many companies maintain tanks of diesel or other chemicals at their construction sites, the SPC Rule could apply to those operations.

LDEQ increased the storage capacity for oil to 1,320 gallons. The applicability threshold for oil, as defined, is the "minimum aggregate aboveground storage capacity [of] 1,320 U.S. gallons.” Only containers with a capacity of 55 gallons or greater are counted. The old capacity threshold (1,320 US gallons for two or more containers in the aggregate within a common storage area, or 660 US gallons for an individual container) no longer applies to oil.

If you have less than 1,320 gallons oil in a common storage area, you do not need an SPC Plan. By way of example, a construction site that stores oil in one 1,000 gallon tank, which was subject to the former version of the rules, would not be subject to the new version.

The amendment does not mention a 'common storage area' when setting the applicability threshold for oil. The aggregate quantity determination utilizes containers greater than 55 gallons but is silent as to whether the containers to be counted may be spread throughout the facility or must be in a 'common storage area.' LDEQ has indicated that the intent was to keep the 'common storage area ' requirement for containers of oil. In other words, only containers of oil greater than 55 gallons in a ‘common storage area’ get counted to equal the 1,320 gallon threshold.

These or similar controls may already be included within your current SWPPP. However, the SWPPP should be reviewed to ensure conformity with these new guidelines.