EPA Addresses Gaps in Wastewater Discharge Rules for Power Plants
October 2, 2009 // Published as a news service by IHS
As the result of several studies, the U.S. Environmental Protection Agency (EPA) will revise existing standards for water discharges from coal-fired power plants.
Earlier this year, the EPA completed a multiyear study of power plant wastewater discharges and concluded that current regulations, which were issued in 1982, have not kept pace with changes that occurred in the electric power industry over the last three decades.
Air pollution controls installed to remove pollution from smokestacks made strides in cleaning the air and reducing respiratory and other illnesses, according to the EPA.
However, some of the equipment used to clean air emissions does so by "scrubbing" the boiler exhaust with water. When the water is not properly managed, it sends the pollution to rivers and other water bodies.
Treatment technologies are available to remove these pollutants before they are discharged to waterways, but these systems were installed at only a fraction of the power plants.
As part of the multiyear study, the EPA measured pollutants present in the wastewater and reviewed treatment technologies, focusing mostly on coal-fired power plants.
Many of the toxic pollutants discharged from these power plants come from coal ash ponds and the flue gas desulfurization systems used to scrub sulfur dioxide from air emissions, experts said.
Specifically, the study focused on:
- Characterizing the mass and concentrations of pollutants in wastewater discharges from coal-fired power plants.
- Identifying the pollutants that comprise a significant portion of the category's toxic-weighted pound equivalent discharge estimate and the corresponding industrial processes responsible for the release of these pollutants.
The EPA's 2007/2008 detailed study was a continuation of a detailed study initiated to support the 2006 Effluent Guidelines Program Plan.
In the 2005/2006 detailed study, the EPA initially investigated whether pollutant discharges reported to the Permit Compliance System (PCS) and Toxics Release Inventory (TRI) for 2002 were accurate in reflecting that the Steam Electric Power Generating Point Source Category (40 CFR Part 423) discharges relatively high amounts of toxic-weighted pollutants, in comparison to other industry sectors.
The EPA also performed an analysis of the reported pollutant discharges and reviewed technology innovation and process changes. Additionally, the EPA evaluated certain electric power and steam-generating activities similar to the processes regulated for the Steam Electric Power Generating Point Source Category but that are not currently subject to effluent limitations guidelines and standards.
During the 2005/2006 detailed study, the EPA identified data gaps and issues that may affect the agency's estimate of the potential hazards caused by discharges from steam electric facilities.
To fill these gaps, the EPA is collecting information on the wastewater characteristics and treatment technologies used at facilities in the steam electric point source category. To date, the EPA collected data for the 2007/2008 detailed study through facility inspections, wastewater sampling, a data request sent to a limited number of companies and various secondary data sources.
Experts said once the new rule for electric power plants is finalized, the EPA and states would incorporate the new standards into wastewater discharge permits.
For more information, review the EPA's Steam Electric Power Generating Point Source Category: 2007/2008 Detailed Study Report.
More information about EPA's study is provided in an interim report published in August 2008. A final study will be published later this year.
Source: U.S. Environmental Protection Agency (EPA).