Pollution prevention spinoffs

Rachel Carson's book on environmental protection, Silent Spring, effected change, particularly for the protection of rivers and lakes. Public pressure on elected officials following the publication of Carson's book played a role in passage of the Federal Water Pollution Control Act Amendments of 1972 (which later became the Clean Water Act). Subsequent regulations have required increasingly stringent standards for water quality and waste treatment, often resulting in increasingly higher wastewater treatment costs.

In Texas, the land of the occasional drought, the high quality of wastewater treatment has led to the good news/bad news quip that, "Wastewater treatment requirements are getting so stringent that we will soon be able to drink our wastewater. However, there may not be enough to go around."

I live in the Dallas-Fort Worth area, in the upper reaches of a Texas river basin. Members of my family live in the lower reaches of the same basin. For a number of years, I took pleasure in kidding my downstream family members about drinking my (treated) wastewater. Then, in the early 1980s, public officials and engineers began to realize that highly treated wastewater is too valuable to give away. Thus, a number of water reclamation and reuse projects were developed to deliver treated wastewater for direct reuse in irrigating golf courses and maintaining water levels in scenic waterways and lakes. Indirect reuse of wastewater, whereby highly treated wastewater is discharged to large water supply lakes, is also becoming accepted.

This is one example of the numerous driving forces encouraging pollution prevention by businesses, cities and other agencies. These driving forces include laws and regulations, economics and public opinion.

Pollution prevention drivers

Example regulatory forces include requirements for source reduction/waste minimization plans by hazardous waste generators, industrial waste pretreatment requirements established for publicly-owned treatment works (POTW), regulations under the Resource Conservation and Recovery Act concerning disposal of hazardous and nonhazardous waste in the appropriate type landfills, air permitting requirements under the Clean Air Act (CAA), wastewater discharge permitting requirements under the Clean Water Act (CWA), and numerous monitoring, reporting and recordkeeping requirements.

Economic issues include the conservation and recycling of valuable resources and the avoidance of costs associated with obtaining permits and performing monitoring, reporting and recordkeeping. A newcomer on the list of economic driving forces is air emission credits, obtained from regulators and either sold to entities seeking permits or kept to offset future permit requirements.

Public opinion has also been shown to be an important driving force in connection with the marketing of industrial products, local taxes on businesses, and the passage of environmental laws.

These often competing driving forces require today's environmental managers to avoid one-dimensional thinking. This can involve asking the following questions related to regulatory, economic and public opinion decisions.

  • What is my objective?
  • Considering the relative importance of various driving forces, have I selected the correct objective?
  • What alternative programs could meet my objective?
  • What are the consequences of each program?
  • What are the consequences of not meeting my objective?
  • What are the pros and cons of each program for meeting my objective?
  • Have I considered all important factors?
  • Have I sought the opinions and advice of other experts and those who may be affected by my decision?

Asking these questions will help an environmental manager to be both effective and efficient. Effectiveness involves not only selecting the correct objective, but also meeting the objective in the most efficient manner.

Water reclamation and reuse

An example of effective environmental management is a project that is currently in the field demonstration stages. It involves the diversion of water from a river that derives most of its dry-weather flow from water reclamation facilities in the Dallas-Fort Worth area. The diverted flow is passed through large constructed wetlands for water quality "polishing" to remove nutrients and other pollutants. Following this polishing process, the water will be pumped to two reservoirs that make up part of the Dallas-Fort Worth water supply. In Texas, where water supplies are not always dependable, the reuse of highly-treated water not only serves as an incentive to prevent pollution, but also provides a valuable resource at a lower estimated cost than development of new water supplies.

Energy recovery at wastewater treatment plants

The treatment of municipal wastewater involves the treatment and disposal of biosolids. At many treatment facilities, one of the treatment processes is anaerobic digestion. In the anaerobic digestion process, biosolids decompose in a warm environment in the absence of oxygen. During this process, a number of decomposition gases are produced, including methane. Many wastewater treatment plants use methane gas as fuel to heat the digester tanks and flare excess methane.

However, in the last half of the 20th century, a number of facilities have developed energy recovery projects that use the excess methane gas to power blowers used in the treatment process, or to generate electricity.

One such facility in the North Texas area has been using large internal combustion engines for this purpose for the past 30 years. Because of increasing maintenance requirements on these existing engines, the facility recently elected to replace them with cleaner-burning gas turbine engines that will power generators tied into the facility's power grid. Because of modern design features, the new turbine engines will significantly reduce air emissions from this facility, while allowing the facility a substantial savings on its power cost. Additionally, the reduced air emissions may become emission credits in Texas' air emission credit banking system. If acquired, these credits can either be sold by the facility or used to offset future air permit requirements.

Energy recovery at landfills

Two spin-offs of the CAA are new source performance standards for new landfills and emissions guidelines for existing landfills. Depending on the size of the landfill and other circumstances, these regulations can require the installation of landfill gas collection and control equipment. Because of the expense of installing this equipment, many landfill operators are giving serious consideration to using recovered gas as an energy source. These regulations should significantly reduce air pollution from a number of large landfills.

Industrial waste treatment changes

Industrial wastewater is typically either treated and discharged directly into a water body under a federal or state National Pollution Discharge Elimination System (NPDES) permit, or treated and discharged into a publicly-owned treatment facility (POTW) under a permit issued by the operator of the POTW. In either case, increasingly stringent treatment requirements have led industries to explore process changes, changes in chemicals used, and waste reduction. In one case, a company that performs metal finishing was having trouble meeting local pretreatment limits for zinc. Parts were being passed along a cleaning and coating line in metal baskets. Because the zinc coating tank was a closed process, no one at the facility could imagine how high levels of zinc were being discharged to the public sewer. Upon investigation, it was learned that zinc was being coated on the metal baskets used to carry parts along the cleaning/coating line. Some of the zinc on the baskets was subsequently being released in an aci d wash tank that was not a part of the closed process. A change in the process and chemical usage solved the problem.

Good citizenship

Because of public opinion and a desire to be good citizens, a number of large industries have adopted a zero discharge philosophy. This philosophy has not only prevented pollution, but has, in many cases, resulted in the creation of beautiful natural habitats. These measures not only save industry money, but also provide valuable positive publicity.

Pollution prevention and global economy

An important concept of pollution prevention is the linking of economic decision making with environmental policy. Because of the growing global marketplace and international concerns with the environment, some companies have been economically pressured to improve their industrial practices in order to remain competitive.

A large Swedish company recently performed an audit of its subsidiary companies to determine which subsidiaries exhibited the company's environmental policy. Their marketability profit margin depended upon the process efficiency associated with pollution prevention and the public's awareness of their environmental stewardship.

The subsidiary that placed last on this audit was a small manufacturer of office products in the midwestern United States. This company was given an ultimatum to "clean up its act" or forfeit its relationship with the parent company. This proactive approach is common at the global level; therefore, prudent companies should plan and prepare so that their compliance with strict international standards will make them a better choice in the global arena.


Experience over the past 30 years seems to indicate that by using a thought process that involves "thinking outside the box," environmental managers can often achieve much more than simply meeting a set of regulations. An understanding of public opinion and other driving forces behind environmental regulations, a knowledge of economic issues and a detailed knowledge of specific regulations and how to make them work in your favor contribute to a win-win situation for all stakeholders.

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This article appeared in the February 2000 issue of Environmental Protection magazine, vol 11, no. 2, p. 29.

This article originally appeared in the 02/01/2000 issue of Environmental Protection.