WINTER 2000
2305 East 5th Street
Duluth Minnesota 55812-1445

septic responsibility
 

 
Introduction
Every time a toilet flushes, do people think about the sewage treatment system that allows for this convenience? Chances are, the answer is "No," although the health of many families and of our surface and ground water resources depend on the responsible management (operation and maintenance) of these systems. The majority of our population relies on municipal facilities that properly treat their sewage. However, at least 27% of households are outside the reaches of municipal sewers. The number of people who are spending more time at homes and cabins outside city limits is also steadily increasing as our population grows, making private septic system ownership more commonplace.

A 1990 census referenced in a Minnesota Pollution Control Agency (MPCA) report revealed that of the 491,925 Minnesota homes not hooked up to public sewers, a staggering 47% of these systems did not conform to state regulations. New rules and alternative technologies have been developed to deal with these problems. Septic owners must remember, however, that whether they own a standard or alternative system, they are ultimately responsible for proper operation and maintenance.

Standard
If it isn't broke, don't fix it, right? Unfortunately, ignoring individual sewage treatment systems until problems arise is often the most expensive way to manage a system, not to mention it is against regulations. The rules of the MPCA Individual Sewage Treatment Systems Program state that, "The owner of an individual sewage treatment system or the owner's agent shall regularly, but in no case less frequently than every three years, assess whether the sewage tank leaks...and measure or remove the accumulations of scum...and solids." A standard system requires this inspection, maintenance, and cleaning through the manhole every 1-3 years, depending on the usage of water and products like detergent that enter the system. Basic tips about proper septic operation can be found in the enclosed brochure, "Taking Care of Your Septic System." Other University of Minnesota Extension Service publications include the "Septic System Owner's Guide," furnishing a complete set of management information, and the new "Understanding Your Septic System," which explains how septic systems work and the most common reasons for failure.

Alternative
New state rules that became effective on October 4, 1999, allow more flexibility for alternative options when situations are not suited for standard systems. County officials work with homeowners and groups to implement these alternative strategies. These systems require even more attention to operate, maintain, and monitor because of the extra components and lack of long-term performance histories of these new technologies. One example of an alternative system element that needs diligent monitoring is an aerobic tank. The owner must regularly check the airflow of this tank so that the air levels are adequate to support the live bacteria that process the sewage. When deciding on a new system, regardless of the type chosen, homeowners must consider the time, commitment, and cost to maintain each system. When multi-household units collect wastewater for treatment in a standard or alternative system, everyone on the system must take responsibility for their uses because their actions affect more than just their household. Appropriate daily use, routine inspections, and maintenance are vital to make every individual sewage treatment system operate successfully for years to come.

question of the season
 
What is, and when should I consider alternative on-site wastewater treatment?

The main goal for on-site wastewater treatment is to return water back to the hydrologic cycle on private individual's property while protecting human health and the environment. Minnesota and many other states are blessed with diverse soils and geology. In many cases, the soils lend themselves to conventional on-site wastewater treatment (trenches and mounds). In some areas, however, standard systems do not perform well because of high water tables, bedrock close to the surface, and fine soils. Additionally, lakes and other environmentally-sensitive areas in Minnesota are susceptible to water pollution. Where soil and geological conditions prevent conventional on-site wastewater treatment from performing well, it makes sense to go the extra mile in treating our wastes to assure that our natural resources will not become degraded.

On many difficult sites, the standard mound system is an accepted and proven way to treat wastewater before it enters the ground. In order to expand the number of tools we have for treating wastewater on difficult sites, people have been seeking alternatives to the standard mound system. Alternative treatment systems will sometimes save space and may not alter the appearance of people's yards as much as a mound system. In many cases, the effluent from alternative systems will give us water that is higher quality (lower in suspended solids, biological oxygen demand, pathogens, and nutrients) when compared to effluent from a septic tank. The theory is: if we can treat wastewater more effectively before we discharge it to the soil, then many of the problems associated with difficult soil conditions can be avoided. The drawbacks with alternative wastewater treatment are that most systems require additional maintenance, more monitoring, and often cost more than standard systems.

Briefly, standard trench and mound systems consist of a septic tank that handles the settling of solids and decomposition of organic solids. The septic tank also stores the non-degradable inorganic and organic solids until the tank is pumped. The wastewater, minus the solids, then flows out of the septic tank and into a series of perforated pipes that are laid in soil trenches, or in the case of a mound system, this wastewater is pumped up into the sand mound. Alternative systems usually have a standard septic tank followed by a pre-treatment device that provides additional treatment of the wastewater before it is discharged into the soil. The pre-treatment devices consist of various technologies, many of which are being researched by the University of Minnesota. Currently, common alternative systems consist of one of the following unit operations: sand and peat filters, constructed wetlands, aerobic tanks, and drip irrigation.

Sand and peat filters operate by filtering the effluent from the septic tank. Water from the septic tank is pumped into a bed of sand or peat that acts as a filtration system to remove organic matter, pathogens, and nutrients. The wastewater can then be dispersed into the soil, similar to a standard drainfield system.

Constructed wetlands, as the name implies, are engineered lined wetlands that act as filtration and nutrient removal systems.

Aerobic tanks are also described well by their name; air is supplied to a specially-designed tank to support the growth of bacteria that use oxygen (aerobic bacteria). Aerobic bacteria are more efficient at degrading organic matter found in wastewater than are the bacteria that typically live in conventional oxygen poor septic tanks (anaerobic bacteria). The use of aerobic tanks results in a much higher quality effluent than that of a typical septic tank.

Drip irrigation is also an alternative treatment system, but the name refers to the way effluent is distributed in the soil rather than the use of pre-treatment devices. Drip irrigation differs from standard drainfields in two important ways: the diameter of drip irrigation lines is much smaller (about 3/4 inch) than standard drainfield pipe (4 inches) and drip irrigation lines generally are placed near the ground surface in the root zone of plants (much higher than a standard drainfield). Drip irrigation can remove more of the nutrients found in wastewater than conventional trench systems because of the location near the root zone of plants. The plants in turn use the nutrients for growth. Drip irrigation requires more acreage than a standard drainfield because smaller quantities of water are distributed over a larger area.

In summary, the goal of alternative versus traditional septic systems is to achieve equal or better treatment of wastewater using a different method. Most often alternative systems are chosen because the soil and space restrictions of the individual site do not allow for a standard system.

what MTBE means to minnesota
 

CBS's 60 Minutes aired a story regarding methyl tertiary butyl ether (MTBE) on January 16, that alarmed people around the nation and generated calls to the Minnesota Water Line. The story exposed the potential liability of the oil industry, but targeted the Environmental Protection Agency (EPA) for approving MTBE as a gasoline additive to decrease air pollution without understanding the effects it could have on ground water.

Adding MTBE to gasoline may have improved air quality in urban areas as mandated by the 1990 Clean Air Act but, within the last two years, it became a new and major source of ground water contamination. The additive is used primarily on the east and west coasts of the United States to increase the octane level of gasoline, thereby reducing carbon monoxide and ozone emissions. MTBE is not added to gasoline sold in Minnesota, although it can be found in low levels within the state, according to the Minnesota Pollution Control Agency.

Ethanol producers, most of which are located in the Midwest, are excited as the EPA considers limiting or banning the use of the toxic MTBE. Ethanol is a corn-derived product and is probably the safest and most inexpensive alternative to MTBE. Ethanol has been used to oxygenate gasoline sold in Minnesota and many other states for years.

 
Want More Facts About MTBE?
Browse the Environmental Protection Agency's MTBE page at www.epa.gov/swerust1/mtbe or call 1-800-426-4791 for a packet of information. The Environmental Protection Agency (EPA) also has a list of Non-EPA Web sites about MTBE at www.epa.gov/swerust1/mtbe/othrlink.htm.

For specific information about MTBE activities in Minnesota, contact the Minnesota Department of Health's Drinking Water Protection Program at 651.215.0770 or the Minnesota Pollution Control Agency (MPCA) at 651.296.6300 or 800-657-3864.

Check out the MPCA's news release that summarizes MTBE activities in our state at www.pca.state.mn.us/news/nr11800.html.

 

publications
 
Taking Care of Your Septic System
The University of Minnesota Extension Service recently published this helpful guide for septic system owners. Cut-away graphics help explain the basics of septic system operation and upkeep. Call the Distribution Center at 800-876-8636 or Extension Service at 612.624.4900 to order additional publications.

Hydrogen Sulfide and Sulfur Bacteria in Well Water
Don't miss this Minnesota Department of Health (MDH) pamphlet that addresses a common taste and odor issue in well water. It identifies potential sources of and treatment options for this drinking water problem. Staff at the MDH Pamphlet Request Line at 612.676.5274 will help you acquire further materials.

 

live 1999 septic satellite conference
 
By Barb Peichel

On October 28, forty-five locations in Minnesota and thirty-five other sites around the country tuned into a live satellite conference on the future of septic systems. Home and cabin owners, local agency staff, educators, elected officials, on-site industry professionals, and researchers participated in this program entitled, "The Next Generation of Sewage Treatment: Flushing in the New Millennium." This conference explored sewage treatment alternatives for areas not suited for the standard trench and mound systems because of high ground water, shallow bedrock, small lot sizes, or poor soil conditions.

A panel of experts discussed the operation, maintenance and costs of these new wastewater treatment options. They interviewed ten people managing wastewater either in private residences, small town groups, or lakeshore communities that have each implemented an alternative septic system. During the interview, these case study participants explained why they decided a certain system was right for their situation. The teleconference also provided perspectives on how individuals and local officials can work together to install new treatment technologies with the proper management and maintenance. The two-hour conference concluded with a session that allowed participants to phone or fax in questions for a live response from the panel.

Need more information about septic systems alternatives? Staff at the University of Minnesota Extension Service can help. Contact Ken Olson at 800-719-2825 or olson150@umn.edu for general information and questions about the operation and maintenance of alternative septic systems. If you are interested in details about the research and design of these new technologies, contact Sara Heger at 612.625.1774 or heger001@tc.umn.edu. If you missed the conference but would like handouts or a videotape of the session, please call 800-719-2825.

SPONSORS of the 1999 Septic System Satellite Conference:

• University of Minnesota Extension Service
• Minnesota Pollution Control Agency
• Minnesota On-Site Sewage Treatment Contractors Association
• Minnesota Department of Health
• National Environmental Training Center for Small Communities
• National Small Flows Clearinghouse

Product vendors and suppliers:

• ABS Pumps
• Ahlgrimm Sales
• Geoflow. Inc.
• Hydromatic/Burk & Associates
• Infiltrator Systems, Inc.
• Insul-Seal Insulation, Inc.
• Pumpco of Minnesota, Inc.
• SJE-Rhombus/SJ Electro Systems, Inc.
• Sta-Rite
• Zabel Environmental Technology