Appendix A: Revised Project Report

Project 1, Project 2, Additional Achievements

Project 1

Objectives:

  1. Establish protocol and procedures for a public health survey of existing on-site sewage disposal practices in Indiana. Determine factors concerning performance of existing and proposed on-site sewage disposal systems in Indiana by county and by type and estimated percentage of systems which are in failure, by county and type.
  2. Create a framework for a data collection program to assist county health office in reporting the needed information to the ISDH.

Purdue University has developed and performed a survey of county health department personnel with respect to their current record keeping practices. The questionnaire also requested information pertaining to the number and reasons for on-site system failure in the county. We received surveys from 70 counties. We divided the counties into 6 soils groups for survey analysis when applicable. Data was analyzed by county using either sums, averages or percentages. The following tables are selected summary data based on responses from 75% of Indiana’s counties unless otherwise noted. Complete data tables and county divisions are located in Appendix C.

Table 1. Soil Group 2

Septic Statistics  
Small communities without municipal sewage

52

% of county served by on-site systems

55%

% of new systems requiring a perimeter drain

86%

Failures primarily limited to particular soil attributes*  
Compact glacial till

100%

Seasonal water table

86%

Fragipan

0%

Coarse sand and gravel outwash

0%

Bedrock

0%

8 Counties Responded (57%)

Table 2. Soil Group 5

Septic Statistics  
Small communities without municipal sewage

44

% of county served by on-site systems

28%

% of new systems requiring a perimeter drain

51%

Failures primarily limited to particular soil attributes*  
Seasonal water table

83%

Fragipan

50%

Compact glacial till

0%

Coarse sand and gravel outwash

0%

Bedrock

0%

6 Counties Responded (75%)
Numbers are averages of counties unless otherwise specified.
* The percentage of counties where the factor was a primary limitation.

Tables 1 and 2 illustrate the variation of limiting soil factors across Indiana. Soil group 2, characterized primarily of silty clay lacustrine deposits and clayey glacial till is located in the north eastern part of Indiana. Soil group 6 is located in the south western region of Indiana and is characterized by discontinuous loess over weathered limestone. Note differences in limiting soil attributes reported.

Seasonal water table was either the first or second most important limitation in all 6 soil groups. Properly functioning on-site systems require about 2 feet of unsaturated soil. Soil organisms which effectively detoxify chemicals and destroy pathogens are primarily aerobic, meaning they require oxygen. If the soil is saturated, the microorganisms are under stress and not as active. To compound this, effluent moves faster in saturated soil, decreasing the time available for treatment. Increased awareness of the importance of soil limitations in combination with requirements specified by the latest rule (ISDH rule 410 IAC 6-8.1) have caused an increase in the number of perimeter drains installed, a vital component for proper system functioning on wet soils. Sanitarians estimate that perimeter or curtain drains are installed in 59% of new systems.

Table 3

Record Keeping Methods  
Current system used (average years)

12

Data entered into computer

62%

Years computerized (average)

6

Records since (average)

1971

Improvement in last 10 years

91%

From the survey results, we learned that counties have few records or data on existing on-site systems in the state. Consistent records for on-site system permits have been kept for approximately 12 years (table 3). Records prior to this are sketchy and incomplete. Of the counties surveyed, 91% of them have improved their record keeping in the last 10 years. Comments indicated that improvements have been made in response to the latest rule. Purdue University played an integral part in the development of ISDH rule 410 IAC 6-8.1 which has improved siting and construction of on-site systems as well as record keeping. Counties had great difficulty estimating both the number of on-site systems and percentage of failing systems in the county. Reasons for failure (table 4) were estimated based on experience and the sanitarians "best guess".

In light of this situation, we constructed a relational database that allows the user to input information about both new and existing systems. This On-site System Wastewater Disposal Database runs in Access ’95 and Access ’97. It can be used as part of the regular permit application and inspection process, therefore allowing constant data collection while limiting extra effort required by county health department personnel. In the case of a repair or replacement system, a survey of the old system is requested including system age, type, and reasons for failure. The database then allows the counties to accurately correlate on-site system information to soil and site information. Summary graphs are built in. This specific data is critical to mapping system performance by type, geographical location, and site and soils information.

The database is based on a new standardized on-site wastewater disposal permit form. To develop this, Purdue University sent letters to the county health departments explaining our project and requesting copies of their on-site wastewater disposal permit application forms. We received 32 forms. From these forms and communication with Alan Dunn at the ISDH, we have constructed a standardized application form (see Appendix F). The database is designed to provide spatial data available for GIS (geographic information system) layering. Fields include street address, section, township, range, and latitude and longitude. It is estimated that at least 20 counties are currently undertaking GIS mapping projects. This work is being primarily performed on a contract basis with private engineering firms.

The database is now available. Prior to this, database was tested and critiqued by 5 counties: LaPorte, Cass, Bartholomew, Vigo, and Tippecanoe. Suggestions were incorporated and the database was sent out to the 11 counties who requested the database in addition to the Missouri Department of Health. The preliminary response has been positive. One feature particularly appreciated is the ability to scan in site diagrams, system diagrams, and soil scientist reports, making the database an electronic folder of information on each permit. Purdue plans to demonstrate and instruct counties on the database at the nine regional public health institutes in late fall. The database is free and can be downloaded from the Purdue On-Site Wastewater Disposal website.

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Project 2

Proposal:

  1. Conduct a literature search of new on-site technologies for which there is little or no experience in Indiana. Write preliminary criteria for the adaptation of the technologies to Indiana.
  2. Survey state health offices at other states around the US to determine the value of experimental systems for use in Indiana. This will entail site visits to other states when necessary to evaluate the most promising systems.
  3. Draft criteria and testing protocol to evaluate the new technology under Indiana conditions.
  4. Work with local homebuilders and homeowners, local health departments and ISDH to design experimental systems, including on-site supervision of construction and installation of monitoring systems.

We have conducted a literature search of relevant journal articles, conference proceedings, and informational publications. Small Flows Clearinghouse has been contacted regarding information on innovative systems. We have asked researchers at other universities around the country about their current work and experiences with alternative systems. Additionally, we surveyed state health departments of neighboring states requesting information about their permit application process, record keeping system, systems approved for installation, and experience with alternative systems. We received 11 questionnaires back. The entire staff has visited Wisconsin. Don Jones has also visited sites in Minnesota and Illinois. Literature on innovative technologies is extensive and new literature is continuously published; accumulation and analysis are expected to be ongoing processes.

Selected literature has been reviewed. We have begun to develop an understanding of available alternative systems and their associated benefits and drawbacks. From this foundation, and the analysis of the survey results indicating reasons for on-site system failure, we have identified the need for allowing effluent pretreatment prior to discharge to a soil absorption field. This information is the foundation for work planned for the 1998 fiscal year.

Table 4, based on survey responses from 69 counties, indicates that wetness, age, system size and the related problem of space are major contributors to failure throughout Indiana. Pretreatment has the potential to allow downsizing of absorption fields. Most types provide discharge of cleaner effluent to soil. This would reduce system failure in marginally soils and extend the lifetime of these systems. Pretreatment technology would allow renovation of failing systems in sites where there are currently no alternatives.

Three pretreatment technologies that have seen success in a wide range of soil and environmental conditions, including those similar to Indiana, are recirculating sand filters, constructed wetlands and aerobic treatment plants. Of the 11 states agencies which responded to our surveys, Mississippi, Pennsylvania, Michigan, and Ohio allow constructed wetlands, Illinois, Mississippi, Pennsylvania, Tennessee, Michigan, Iowa, Wisconsin and Ohio allow recirculating sand filters, and Illinois, New York, Minnesota, Mississippi, Pennsylvania, Iowa, Wisconsin, and Ohio allow aerobic treatment units. Missouri was the only state that did not permit any of the treatment alternatives. Indiana has not used recirculating sand filters, but ISDH personnel are interested in exploring the potential that this technology has for the state. ISDH now permits the use of constructed wetlands for pretreatment for both commercial and residential on-site systems on an experimental basis. ISDH rules also permit the use of aerobic treatment plants in lieu of a septic tank for commercial and residential on-site sewage disposal systems. The aerobic treatment plant must discharge to a properly sized and designed soil absorption field. However, ISDH has not encouraged this pretreatment technology because of its maintenance requirements, as Indiana does not have an operation and maintenance program. Procedures for the evaluation of experimental systems in Indiana have been drafted (Appendix B). Additionally, Wisconsin has developed procedures for acceptance of innovative technologies based on system performance.

The on-site staff performs numerous on-going consultations with both contractors and homeowners regarding system applications for difficult sites. These will continue throughout the project with emphasis on assistance with alternative design. To facilitate this, Purdue University has sent a letter to county health departments offering assistance. Through this, we have identified the need for summary information on innovative technologies and their potential in Indiana, free of copyrights. We are receiving calls from contractors and other interested parties requesting this information with increasing frequency. The literature review is the foundation for extension materials. Additionally, we are planning to make this report available from our web site.

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Additional achievements

We have formally presented our project at four meetings, with another 10 scheduled this fall. The renewal of the on-site project has been met with enthusiasm and relief by both health department and industry personnel.

To increase communication and education, we have started publishing a project newsletter. The newsletter covers educational information relating to on-site wastewater disposal systems and project updates. The first three issues have been distributed. This newsletter has gone to county health department personnel, state health department personnel of all states that have state on-site programs, Indiana agricultural and natural resource extension educators, various Indiana state representatives, and university researchers around the country who have been contacted for information about their programs. The third issue of the newsletter also went to on-site wastewater contractors and consumer and family science extension educators around the state.

We have built an on-site wastewater disposal homepage for the World Wide Web that contains the newsletters, extension publications, project results and other useful information relating to on-site systems. This site is located at http://www.agry.purdue.edu/agronomy/landuse/septic/septic/septic.htm and is continually updated as information is deemed valuable.

Four trifold display panels describing the use, advantages, and construction of conventional, pressure distribution, at-grade, and mound systems have been constructed or refurbished for use in extension activities. These were displayed at Indiana’s Land Improvement Contractors Association (LICA) field day. At the field day we talked to numerous contractors and homeowners and distributed brochures outlining on-site system theory and care.

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An Evaluation of On-Site Technology in Indiana: Table of Contents