WINFIELD TOWNSHIP WATEWATER FACILITY PLAN
Overview of Options for
Management Strategies and Technologies

1. INTRODUCTION

The purpose of this document is to provide the Township Board and citizens of Winfield Township with a review of the options for wastewater management strategy and the technologies most appropriate for use within each strategy. This is not a "how-to" manual, it does not contain specific instructions for how the Township is to proceed. It is intended to be a basic introduction, to be used by Winfield Township to help it determine the specific methods to be explored further, culminating in the preparation of a wastewater facility plan to be submitted to the Pennsylvania Department of Environmental Protection (DEP). Only by understanding all the options-and how they relate to conditions in the township-can there be any hope of deriving the best one for Winfield Township.

To minimize potential confusion to the lay reader, it should be understood that the term "management" has a dual definition in these discussions. A wastewater management strategy or system encompasses both the "hardware" by which the strategy is implemented and the system of human control and oversight of those facilities. But "management system" can also refer specifically to only the latter-the institutional mechanisms by which the system is planned, implemented and maintained. With this pointed out, the meaning in each context should be clear.

First, a brief discussion on setting of goals for the facility planning process is offered. Next, several generic management strategies are considered, and the pros and cons of each for Winfield Township are discussed. Then options for collection, treatment, and dispersal system technologies are reviewed, pointing out the strengths and weaknesses of each in the context of the various management strategies and for the conditions in Winfield Township. This also entails consideration of the regulatory requirements regarding treatment quality and the regulatory acceptability of various technologies. Therefore, this document should also be reviewed by and discussed with DEP. This report closes with a general discussion of the structure and function of the wastewater management system that may have to be created to properly run the type of wastewater hardware system that Winfield Township chooses.

2. GOALS OF THE WASTEWATER FACILITY PLAN

As the following discussions will make clear, certain strategies serve certain goals better than others, and certain technologies may work better with each strategy and to achieve protection of public health and environmental values. In order to make sense of this information, the community must "filter" it through what it hopes to accomplish with this facility plan. So a first order of business is for Winfield Township to formulate those desires as goals for the plan. This is something ONLY the community can do. A consultant can do no more than suggest what might be taken into consideration; his judgment cannot be substituted for that of the citizens who will have to implement, pay for and live with the final plan.

It is preliminarily suggested that there are at least two types of goals that Winfield Township must formulate and against which any options must be evaluated. One is community goals and the other is environmental protection. Preliminary suggestions for factors that might be considered within each category are offered below:

Community goals:

• Growth management - encouraging, accommodating, discouraging, thwarting
• Cost sharing arrangements - who pays vs. who benefits
• Ability to pay - level of public sector assistance with private sector contributions
• Level of public sector involvement - level of tax or fee derived revenue
• Level of public sector involvement - degree to which pubic sector intervenes/participates in historically private sector activities

Environmental quality goals:

• What needs to be protected?
• How well does it need to be protected?
• Address current failures only, or protect against future failures?

3. GENERIC MANAGEMENT STRATEGIES

There are six generic management strategies that could be considered as the basis for installing a wastewater management system. These are listed below and discussed in turn. In general, the order in which they are listed proceeds from least to most direct public participation in planning, design, permitting, execution and operation of the resulting wastewater system.

1. Conventional on-site management
2. "Improved" on-site management, with an organized oversight function
3. Small-scale collective systems, with dispersal on the sites generating the flow
4. Small-scale collective systems, with dispersal or discharge off site
5. Large-scale collective systems utilizing "alternative" sewerage systems
6. Large-scale collective systems utilizing conventional sewerage systems

It should be noted throughout the following discussions that reference is made to a public entity that would be provided powers and would assume duties in regard to planning, design, installation, oversight, and operations and maintenance of some or all of the wastewater system facilities. This use of a generic term rather than "Winfield Township" highlights that the form of any public entity created to exercise those functions is yet to be determined. That matter will be better addressed after the decision has been made as to the specific powers and duties that entity will require. For the present, keep in mind that this public entity is not necessarily the Township.

3.1 Conventional on-site management

Under this strategy, each house and business has its own, individually owned on-site system which is permitted, constructed, operated and maintained under current arrangements. As this is the strategy presently being employed in Winfield Township, it constitutes a "do nothing" option, organizationally speaking, although somehow, some way, both currently identified and future system failures would have to be brought to proper working order. Advantages of continuing with this management strategy include:

• For the most part, institutional arrangements to support this strategy are already in place. As noted in the discussion of disadvantages, however, some of the identified problems may require arrangements that may not be readily achieved without facilitation of some sort by appropriate governing bodies, which is not available at present.
• Subject to regulatory acceptability, technologies providing enhanced pretreatment and/or improved dispersal methods to cope with site constraints can simply be "plugged in" to this management strategy.
• Private sector oversight and maintenance can be provided through existing institutional arrangements.
• This is the least intrusive method of implementing a management strategy using technologies that include on-lot components, as the arrangements for oversight and maintenance are between owners and private sector entities. Government does not "intrude" onto private property except in an enforcement role.
• This strategy requires the least input of public-sector resources (tax or fee derived revenue).
• This strategy provides the least "invitation" to growth, since it precludes the introduction of public wastewater infrastructure of any sort.
• This strategy allows each lot to be addressed independently. Problem systems can be taken care of while lots with properly functioning systems can be left alone.

Disadvantages of continuing with the existing management strategy include:

• Problems have been identified in Cabot and Marwood which will require the construction of new systems, not all of which may be accommodated within the boundaries of the lots in question. To address these problems under existing arrangements would require the owners to broker on their own arrangements for off-site facilities, mainly dispersal fields, to create code-compliant systems.
• To cope with constraints on some sites may require pretreatment and/or improved dispersal methods which may not currently be accommodated by the existing regulatory structure. To address the problems through these means would require each owner to individually deal with the regulatory problems.
• Addressing these problems with individual systems in every case may be significantly more costly than addressing them through some form of collective solution.
• Oversight through strictly private sector arrangements may be a questionable strategy in terms of assuring on-going viability of the overall management system. Without active public oversight of the process, it may not be possible to even ascertain if the job is being done well.
• While it does not "invite" growth by providing public wastewater infrastructure, this strategy does not preclude growth, which can be accommodated by the implementation of private infrastructure. That infrastructure does not have to conform to this management structure-a private development could install a collective system on its own. This indicates that this strategy may in fact DECREASE community control of growth within the township relative to more "proactive" strategies.
• Existing institutional arrangements are conducive to encouraging or enforcing the use of the technologies that are specifically recognized in the current code. These may not be the ones most readily controllable/maintainable and which would entail the least threat to public health and environmental values as they proliferate. This strategy does not address the question of whether systems that merely meet the current on-site system code actually do adequately protect public health and environmental values, rather it blindly accepts that proposition. Thus, it may be vulnerable to the future changes in the code found to be necessary to provide adequate protection.
• A proliferation of different types of systems, installed at the discretion of each owner, will pose a barrier to efficient transition to public control/oversight if that is eventually determined to be required to assure protection of public health and environmental values.

Discussion of the conventional on-site management strategy:

It appears that, if arrangements could be made for off-site facilities for certain properties, Winfield Township COULD continue to rely on the existing institutional arrangements for wastewater management. However, it is questionable if those arrangements could be guaranteed for all cases which require them without public sector intervention. It is also questionable whether this strategy would result in the lowest total cost to the community, including both public and private investment, and it is questionable whether sufficient oversight of installation and on-going operations and maintenance could be assured. It is also clear that the existing institutional arrangements have not been willing to deal with the identified problems to date, and there appears to be no promise that they can do that effectively. These considerations indicate that this is a questionable choice for assuring that the management system could correct existing problems or would continue to be viable as conditions change in the future.

3.2 "Improved" on-site management

This is a strategy which affords utilization of many existing arrangements while dealing with some of the most problematic aspects of the "do nothing" strategy. Again each property would have its own system, but there would be more public sector involvement in planning and oversight. Advantages of this management strategy include:

• An active public sector management system could broker arrangements for off-site facilities where these are required to create a code-compliant system. Also, if the management system were set up to accommodate them, there would be the possibility of including some small-scale collective systems where that would be required or more expeditious.
• Continued reliance on private sector financing of all improvements minimizes public sector resources (tax or fee derived revenue), although new revenue would be required to man the expanded public control/oversight duties.
• Active management under public sector control/oversight provides greater assurance that the most effective methods would be used and that they would be operated and maintained so as to assure that they remain viable.
• Subject to regulatory acceptability, technologies providing enhanced pretreatment and/or improved dispersal methods to cope with site constraints can simply be "plugged in" to this management strategy.
• Some of the existing arrangements for oversight and maintenance could be continued through appropriate contractual arrangements with private companies that provide these services.
• The public management system could deal collectively with the regulatory issues, relieving each owner from having to individually gain approval for methods currently inadequately addressed by the regulatory structure.
• This strategy still offers little "invitation" to growth as it does not provide for public wastewater infrastructure.
• This strategy allows each lot to be addressed independently. Problem systems can be taken care of while lots with properly functioning systems can be left alone.

Disadvantages of continuing with exclusively private-sector funded on-site management, even with improved arrangements for pubic control/oversight, include:

• It is questionable whether "improved" public control/oversight arrangements would be any more successful at enforcing or encouraging the methods which will be most easily operated and maintained and which will entail the least long-term threat to public health and environmental values. Each owner would still have the option of doing the minimum required to meet the regulations, thus perhaps thwarting a move to a truly "improved" management system. Considerable alterations in the regulatory structure may be needed to address that problem.
• Addressing the problems with individual systems in every case may be significantly more costly than addressing them through some form of collective solution.
• Even with "improved" public control/oversight, exclusive use of individual systems may create a situation which is less "controllable" and harder to police than some form of collective solution for the same properties.
• While it does not "invite" growth by providing public wastewater infrastructure, this strategy does not preclude growth, which can be accommodated by the implementation of private infrastructure. This indicates that this strategy may in fact DECREASE community control of growth within the township relative to other options.
• It is uncertain what legal authority the proposed public entity would have to "overlay" an expanded public control/oversight function on the institutions that currently permit on-site systems and police their oversight.

Discussion of the "improved" on-site management strategy:

Adding a public control/oversight function provides an avenue to creating arrangements which can guarantee that a code-compliant system could be provided for every property. This public function can also provide greater assurance that systems would indeed be operated and maintained so as to remain viable, assuming they were designed to remain viable to begin with. However, with all systems being privately funded, and with the regulatory function still being routed through the on-site system regulatory machinery, it is questionable whether systems that would truly be viable over the long term would be chosen by every, or even most, property owners. This could be addressed by also empowering the public control/oversight system to dictate system type, or even for the individual systems to be turned over to public ownership. These options would most likely require changes in the regulations which the Township could not unilaterally impose, and there may be considerable distaste among township citizens for the idea of public ownership of individual systems. It is also questionable whether this strategy would result in the lowest total cost to the community, including both public and private investment. Further, because this strategy depends on private investment to implement all improvements, there will still be the same reluctance to impose those expenses on township residents which has resulted in the existing problems having been left unattended. This strategy is rooted in a mindset that wastewater management is strictly a private matter to be unilaterally addressed by each property owner. It should be questioned whether it is instead a community function to be addressed collectively by the community as a whole.

3.3 Small-scale collective strategy, with dispersal on the sites generating the flow

The small-scale collective strategy acknowledges that communal action is needed to solve at least some of the wastewater management problems within Winfield Township. In addition to the public control/oversight function incorporated by the "improved" on-site strategy, a public entity would facilitate planning, design, funding and installation to implement collective systems. Septic tanks on each lot feeding effluent to the communal treatment center through small-diameter sewers is the type of collection system most likely to be used with this strategy. Two ways of implementing this strategy can be entertained. The first one is to utilize private greenspace on the lots generating the flow to house dispersal fields. The advantages of this management strategy include:

• The public entity would, in theory, control choice of system type, providing greater assurance that choices would be made with an eye toward long-term viability of the entire management system.
• Collective systems are likely to be less expensive per lot than individual systems where enhanced pretreatment and/or dispersal systems are required to cope with site constraints.
• Investment in dispersal field areas is minimized by utilizing private greenspace that would have housed individual fields in any case. While easements would be needed to facilitate public maintenance of the fields, it is expected that these could be obtained for far less cost than the purchase of space for communal fields.
• Individual on-site systems could still be utilized under this strategy where they are more cost efficient and it is possible to provide proper protection of public health and environmental values with an individual system.
• This strategy provides great flexibility to suit the management system to the specific situation of each property, allowing each neighborhood to be addressed independently. Problem areas can be taken care of while neighborhoods with properly functioning systems can be left alone.
• Public sector investments (tax or fee derived revenue) can be minimized by requiring private-sector financing of on-lot facilities, using public-sector funds only for the communal facilities.
• The public control/oversight entity could broker arrangements for "transfer" of dispersal field space (and construction cost, if fields are constructed with private-sector funds) from one lot to another when one or more lots in a "cluster" being served by one treatment center could not accommodate field area large enough for its flow.
• Private-sector funding could be routed through the public entity, with that entity in charge of all installations under unified contracts, rather than each lot owner contracting individually for construction of on-lot facilities. This may result in lower overall costs for that construction, and would certainly afford much better coordination and uniform quality of the construction.
• Since this strategy relies on soil dispersal systems and does not provide extensive pipe systems, it is still not very "inviting" to growth. Requiring soil dispersal as the means of placing the water back into the hydrologic cycle imparts some degree of density restriction on development.

Disadvantages of the small-scale collective strategy with on-lot dispersal include:

• The legal status of the type of management entity envisioned under this strategy, including the powers it may be allowed, is unknown at this point.
• Permitting of a combined public/private system may be a challenge without considerable reworking or "flexible interpretation" of applicable rules.
• The arrangements required to utilize private greenspace as a part of a public wastewater system are unknown at this point.
• Citizens of Winfield Township may take a dim view of using dispersal fields on private greenspace as a part of a public wastewater system.
• How readily space for communal treatment units may be located and acquired so as to make this option cost efficient is unknown at this point.
• Although this strategy does not "invite" growth, it does not preclude growth, which can be accommodated by the implementation of private infrastructure or of these small-scale communal systems.

Discussion of the small-scale collective strategy with on-lot dispersal:

This strategy provides a mechanism for addressing with communal systems situations that are highly problematic for on-site management. There would be an expanded role for the public entity, and requirements for public funding would be greater than for previous options. This expanded role would no doubt include the authority to unilaterally determine treatment and dispersal methods, so that the choices expected to be most viable and manageable over the long term could be specified. Public ownership of the communal facilities also implies direct public control of operations and maintenance, providing greater assurance that it would be consistently applied. However, the actual work could still be performed by private companies under contract to the public sector entity. Note that most of the objections to this strategy are institutional in nature. If this type of strategy is found to be most cost efficient, then these problems would bear exploration to see if the barriers could be addressed and surmounted.

3.4 Small-scale collective strategy, with dispersal or discharge off-site

The other way to implement this basic strategy is to route effluent from the communal treatment facilities to communal dispersal fields or to discharge the effluent to surface waters. The advantages of this strategy include:

• The public entity would, in theory, control choice of system type, providing greater assurance that choices would be made with an eye toward long-term viability of the entire management system.
• Collective systems are likely to be less expensive per lot than individual systems where enhanced pretreatment and/or dispersal systems are required to cope with site constraints.
• Individual on-site systems could still be utilized under this strategy where they are more cost efficient and it is possible to provide proper protection of public health and environmental values with an individual system.
• Communal fields would be on land under public control. Direct public funding and control of all parts of the collective systems will make the institutional arrangements more straightforward than a combined public/private system.
• This strategy provides great flexibility to suit the management system to the specific situation of each property, allowing each neighborhood to be addressed independently. Problem areas can be taken care of while neighborhoods with properly functioning systems can be left alone.
• This strategy does not provide extensive pipe systems so, especially if it relies on soil dispersal systems, it is still not very "inviting" to growth. Requiring soil dispersal as the means of placing the water back into the hydrologic cycle imparts some degree of density restriction on development.

Disadvantages of the small-scale collective strategy with dispersal or discharge off-site include:

• The legal status of the type of management entity envisioned under this strategy, including the powers it may be allowed, is unknown at this point.
• Although this strategy does not "invite" growth, it does not preclude growth, which can be accommodated by the implementation of private infrastructure or of these small-scale communal systems.
• If discharge rather than soil dispersal is employed, this strategy is more "inviting" to growth than the previous options. If effluent is discharged to surface waters, it is likely that each discharge point would need to be monitored. If there are several monitoring points, this would create high monitoring costs.
• More public funds (tax or fee derived revenue) would be required to purchase field areas and to construct them.
• How readily space for communal treatment units and dispersal fields may be located and acquired so as to make this option cost efficient is unknown at this point.

Discussion of small-scale collective strategy with dispersal or discharge off-site:

This version of the small-scale collective strategy removes the institutional problems associated with using private greenspace to house the dispersal fields, and also opens the possibility of surface discharge from appropriately policed systems. Allowing surface discharge is a two-edged sword in regard to growth management, in that it removes a density restriction inherent in requiring soil dispersal systems. A number of individual discharges would likely create high monitoring costs, but this could be addressed by piping all discharges to one point (assuming they were all located within reasonable proximity), or by negotiating "creative" monitoring requirements-e.g., routinely monitoring only an easy to detect "indicator" parameter like turbidity with much less frequent monitoring for the conventional parameters (BOD, TSS), or executing monitoring on a composite sample of all discharges. The latter, however, could "mask" problems with one of the discharges, which might then go on uncorrected for some time. If soil dispersal is required, locating appropriate spaces for this within reasonable proximity of each system may be a difficulty. Overall, this may be the most workable way to implement a "decentralized" strategy that precludes extensive pipe networks which could simply be tied to larger systems in the future.

3.5 Large-scale collective strategy, using "alternative" sewerage systems

This strategy would create a more extensive collection system utilizing "alternative" technologies. These include effluent sewers, grinder pump pressure sewers, or vacuum sewers. The treatment system at the end of the pipe may be an "alternative" strategy like biofiltration or a "conventional" technology like activated sludge. Advantages of this basic strategy, without regard to the advantages and disadvantages of the treatment system options, include:

• Site constraints in each neighborhood for locating dispersal fields or for spaces to house small-scale treatment systems are no longer of concern. The only requirement is the availability of a sewer line corridor.
• This corridor can be very narrow. The small diameter pipes used in the "alternative" sewerage systems can be installed more shallowly in narrower trenches than conventional sewer mains, typically using machines that can work in a more confined space. They can even be installed using directional drilling equipment, eliminating the problems of trenching through existing neighborhoods.
• The "alternative" sewer lines do not require exact grades, making them much easier to lay.
• The "alternative" sewerage systems are essentially sealed, so infiltration/inflow is typically not a problem.
• If effluent sewers are used, septic tanks at each generator would still be required, but as detailed later, this strategy offers several practical advantages.
• Any treatment system is moved to one location, so there would be only one effluent stream to monitor and one system to operate and maintain, although how much advantage this offers is subject to choice of treatment technologies, as detailed later.

Disadvantages of the large-scale collective strategy using "alternative" sewerage systems include:

• A large-scale collection system is more "inviting" to growth. Even though an "alternative" sewerage system may be used in Cabot and Marwood, these could still be readily hooked up to a "regional" large-pipe collection system in the future.
• Depending on treatment technologies and effluent quality limits imposed, one larger scale plant may be more costly to build and/or to operate and maintain than several smaller plants.
• A large-scale collective system is essentially an "all or none" proposition for the area served. Economics typically dictate that everyone within reasonable proximity must hook up to the sewer, so the up front cost required to implement the system may be much higher than for options which allow flexibility to address only problem lots or neighborhoods.
• If everyone is required to hook up to a centralized system regardless of the status of their on-site system, this may be distasteful to township citizens because it would "punish" those who have invested in a code-compliant system and "reward" those who have chosen not to address the problems.
• If effluent is discharged to surface water, one large point source constitutes a larger threat to public health and environmental values than would several smaller ones, since any one mishap would likely release a greater volume of poorly treated effluent.
• If effluent is discharged to surface water, one large point source is likely to incur more stringent effluent limits than several smaller ones.
• If effluent is routed to soil dispersal fields, one large field creates the need for a complex distribution system and requires a large area of suitable soil somewhere in the lowest area of the community, most likely resulting in groundwater mounding under the field becoming a critical design issue.

Discussion of large-scale collective strategy with "alternative" sewerage system:

This strategy is essentially the approach proposed in the existing draft of the facility plan except that an "alternative" collection system would be utilized. There are questions about impacts on growth management strategy and about how well funds would be targeted at real threats to public health and environmental quality. Concentrating all flow to one point increases the vulnerability of the system to mishaps or neglect. However, depending on the treatment technology employed, and upon the effluent limits for one large discharge vs. the limits for several smaller dispersed systems, one larger treatment plant may be less expensive to build and to operate and maintain than several smaller plants. It remains to be seen if this is really so and if the savings would more than offset the cost of additional sewer line entailed by this strategy.

3.6 Large-scale collective strategy, using conventional sewerage systems

This strategy creates a more extensive collection system utilizing a conventional sewerage system. Again the treatment system at the end of the pipe may be an "alternative" strategy like biofiltration or a "conventional" technology like activated sludge. Advantages of this basic strategy, without regard to the advantages and disadvantages of the treatment system options, include:

• Site constraints in each neighborhood for locating dispersal fields or for spaces to house small-scale treatment systems are no longer of concern. The only requirement is the availability of a sewer line corridor.
• The conventional sewerage system is "standard" construction.
• Any treatment system is moved to one location, so there would be only one effluent stream to monitor and one system to operate and maintain, although how much advantage this offers is subject to choice of treatment technologies, as detailed later.

Disadvantages of the large-scale collective strategy using conventional sewerage systems include:

• A large-scale collection system is more "inviting" to growth. The community collection systems in Cabot and Marwood could be readily hooked up to a "regional" sewer system in the future.
• Depending on treatment technologies, one larger scale plant may be more costly to build and/or to operate and maintain than several smaller plants.
• A large-scale collective system is essentially an "all or none" proposition for the area served. Economics typically dictate that everyone within reasonable proximity must hook up to the sewer, so the up front cost required to implement the system may be much higher than for options which allow flexibility to address only problem lots or neighborhoods.
• If everyone is required to hook up to a centralized system regardless of the status of their on-site system, this may be distasteful to township citizens because it would "punish" those who have invested in a code-compliant system and "reward" those who have chosen not to address the problems.
• The conventional sewerage system would no doubt be more costly to construct through existing neighborhoods than the "alternative" small pipe systems.
• Conventional sewerage systems are prone to infiltration/inflow, a problem that typically intensifies with time, eventually leading to costly rehab projects or to requiring considerable oversizing of the treatment works to accommodate storm surges (or to allowing poorly treated "bypasses" during wet weather).
• If effluent is discharged to surface water, one large point source constitutes a larger threat to public health and environmental values than would several smaller ones, since any one mishap would likely release a greater volume of poorly treated effluent.
• If effluent is discharged to surface water, one large point source is likely to incur more stringent effluent limits than several smaller ones.
• If effluent is routed to soil dispersal fields, one large field creates the need for a complex distribution system and requires a large area of suitable soil somewhere in the lowest area of the community, most likely resulting in groundwater mounding under the field becoming a critical design issue.

Discussion of large-scale collective strategy with conventional sewerage system:

This strategy IS the approach proposed in the existing draft of the facility plan. There are questions about impacts on growth management strategy and about how well funds would be targeted at real threats to public health and environmental quality. Concentrating all flow to one point increases the vulnerability of the system to mishaps or neglect. Here again, depending on the treatment technology employed, and upon the effluent limits for one large discharge vs. the limits for several smaller dispersed systems, one larger treatment plant may be less expensive to build and to operate and maintain than several smaller plants. It remains to be seen if this is really so and if the savings would more than offset the cost of additional sewer line entailed by this strategy. It is questionable whether a conventional sewerage system offers any advantages over an "alternative" sewerage system if a large-scale strategy is chosen, especially since it would likely entail a higher cost and would eventually suffer infiltration/inflow problems.

4. TECHNOLOGY OPTIONS REVIEW

4.1 Sewerage Technologies

4.1.1 Effluent sewers

This technology is used to convey septic tank effluent from the tank to further treatment or to a remote dispersal field. Thus, to use effluent sewers requires that septic tanks be installed at each generator to intercept the raw wastewater flow and to separate out settleable solids. Advantages of effluent sewers include:

• Because they carry only liquid effluent, effluent sewers can employ small-diameter pipes and can be very flexibly routed. Varying, non-uniform grades can be used-even locally negative gradients are allowed-so construction is somewhat easier.
• The small-diameter pipes can be flexed, so that curvilinear routing can be used instead of elbows to change pipe direction, further enhancing routing flexibility.
• No minimum flow velocity needs to be maintained to prevent solids deposition, so gravity effluent sewer lines can be laid on significantly smaller grades than conventional mains.
• Because routing is so flexible and very small grades can typically be used, burial depth is generally quite shallow. The small pipes and shallow burial allow installation in a very narrow construction corridor. This allows effluent sewers to be more easily fit into the built environment.
• Shallow, narrow trenches obviate expensive trench safety requirements-workers do not usually enter the trenches at all-and minimize the need to dewater the trenches.
• The small pipes typically are joined with solvent cement joints and cleanouts instead of manholes are used to access the system if cleaning is needed. Therefore, infiltration/inflow is typically not a problem in the pipe system.
• The smaller pipes, shallower burial, narrower construction corridor, more flexible routing, lack of manholes, etc., allow effluent sewers to be installed at far lower cost than conventional mains.
• Because effluent sewers can run at very small grades, gravity flow can be maintained for a longer distance relative to conventional mains without requiring deep trenches. This can allow some or all lift stations to be eliminated in some circumstances.
• Where lift stations are needed, relatively simple effluent pump stations are used.
• The reduced number and greater simplicity of pump stations can impart further cost savings.
• Where grades are unfavorable, septic tank effluent pump (STEP) systems can be used, with a small pump station at each septic tank, or perhaps for a group of tanks. STEP systems can be used only where grades require it, utilizing gravity flow in the rest of the system.

Of course, an effluent sewer system requires that septic tanks also be installed-and paid for. Typically, however, even with the cost of septic tanks added in, an effluent sewer system is less costly than a conventional sewer system of equivalent coverage. While they might be thought of as an operational liability, using septic tanks for the first stage of the treatment process can provide several advantages:

• The septic tanks, if properly designed, provide considerable pretreatment, reducing organic and solids loading on downstream treatment processes.
• Septic tanks comprise the major sludge handling system. Sludge separation and storage in septic tanks is a passive process, requiring no operator intervention until the tank is pumped.
• Sludge digestion in septic tanks is an anaerobic process, which-relative to aerobic sludge digestion typically employed at conventional treatment plants-greatly reduces the volume of solids to be eventually handled.
• Because the sludge from each generator is segregated, it can be classified by source. Sludge from domestic sources very rarely contains contaminants which render the sludge unusable as a soil amendment, and the input to each tank is relatively "secure" against unauthorized dumping of hazardous materials. Being readily reusable, this sludge stream is a potential revenue source.
• Sludge from each tank only needs to be handled at very long intervals. Therefore, even though there would be many dispersed sources, sludge management logistics would not be untenable.
• Sludge handling is executed without taking any part of the system out of service. Each tank can be pumped in a very short amount of time, and the users can even load the system while it is being pumped.
• Sludge handling is executed in small increments-a pumper truck pumps out one or a few tanks at a time. This allows maximum flexibility in planning for sludge handling.
• Timing of sludge removal is not critical because sludge builds up very slowly. Several months could pass between the time that sludge depth monitoring indicates pumping should be executed and the time that pumping actually occurs without significantly degrading effluent quality. This offers the opportunity to pump at a time of the year when the sludge could be directly landspread, perhaps eliminating the need for intermediate treatment or storage facilities.
• Institutional arrangements for sludge handling are already in place. Existing septic tank pumpers could be contracted to pump the septic tanks.
• Eventually, if these types of systems become widely employed, it may become more cost efficient to institute some form of unified sludge management program, such as one or more composting centers, and perhaps for the management entity to own and run its own fleet of pumper trucks, but these costs can be deferred for many years. In fact, since it would be several years before the first pumping is required, all costs of a sludge handling system, no matter what its form, can be deferred until the time it is actually needed.

The most significant disadvantage of an effluent sewer system is that it is an "alternative" technology, often unfamiliar to the design and regulatory communities. This sometimes results in a very conservative design being enforced, negating much of the cost advantage. Of course, the septic tanks feeding into the effluent sewer system must be watertight; otherwise a considerable additional hydraulic load due to groundwater infiltration would be imposed on the downstream processes. Also, because septic tank effluent is delivered to further treatment processes, they should be of a type that precludes odor problems, implying that effluent sewer systems would be best employed with treatment technologies that typically use septic tanks for pretreatment in any case, such as sand filters.

4.1.2 Grinder pump pressure sewers

It does not appear that a grinder pump system would be advantageous for the conditions in Cabot and Marwood. The previous draft facility plan indicates that the entire area to be sewered in each community would flow by gravity to the proposed treatment center locations, even when using conventional sewers. Therefore, it appears there would be no need for pumps in the collection system, implying that a grinder pump pressure sewer system would impose higher costs and operational complications without offering commensurate advantages.

4.1.3 Vacuum sewers

This system uses a central "vacuum station" to essentially "suck" wastewater through the sewer lines to it. This system is most advantageous in very flat terrain where other sewerage systems would require a number of pump stations. The vacuum sewer system allows all the machinery to be located in one place. Of course, this could also be viewed as a disadvantage, as function of the entire system is lost if there is a problem with the vacuum pumps. Using small pipes, this technology shares many of the routing and line depth advantages of effluent sewers. Disadvantages include a higher energy and operational requirement, the need for more exact grade alignment during installation, limitations on allowable system lift, greater infiltration potential, and less tolerance for flows exceeding design capacity. Since conditions in Cabot and Marwood are not favorable to this technology, these liabilities indicate that vacuum sewers are a poor choice in Winfield Township.

4.1.4 Conventional gravity sewers

Conventional sewers are the "mainstream" technology, so are more broadly acceptable to regulators, and are more familiar to designers and contractors. Because of all the disadvantages relative to small-diameter sewers noted above, conventional sewers are generally much more costly to install. Their installation would also be much more disruptive of the communities. Further, as noted in the discussion of management strategies, this system is prone to infiltration/inflow problems, which usually worsen over time. A major advantage of conventional sewers is that they deliver a "conventional" wastewater to a treatment plant, so that "conventional" technologies like activated sludge would accommodate it very well. On the other hand, this might be considered a disadvantage for a treatment concept that requires a septic tank-or similar primary pretreatment-as the first stage. In any case, conventional sewers would be applicable only to the large-scale collective strategy.

4.2 Treatment Technologies

4.2.1 Sand/gravel filters

This is an old technology that has been modified and improved steadily over the last 50 years. It is a bed of coarse sand or fine gravel that is intermittently dosed. The wastewater drains through the bed and is treated by the same physical, chemical and biological processes that operate in a soil dispersal field. The "modern" version of this technology incorporates recirculation, enhanced pretreatment, steady-state hydraulic loading, frequent dosing, and uniform distribution. A system engineered to optimize all these features has been termed "high-performance biofiltration". Advantages of this technology include:

• The treatment process is inherently stable and robust. Treatment is accomplished by a diverse ecology, including many trophic levels of organisms, and by physical and chemical processes that are inherent to the filtration process. It can readily accommodate variable loading without compromising effluent quality.
• The treatment process itself is passive, not depending on inputs of energy or adjustments in operating conditions (once the system is set up) to keep the process viable. Pumps merely move water through the system. A pump failure does not immediately compromise the treatment process, and once the failure is corrected, the system continues to operate normally without a startup period of less than adequate treatment.
• A number of products are on the market to implement and support this technology.
• The technology is readily "scalable"-it can be implemented for a single home or for an entire community without compromising the technology.
• The system can be implemented in "modules" so that expansion of larger systems can be readily accommodated without interrupting the treatment process. These modules can be fairly small, so the system can be expanded in small increments of capacity. The system can therefore be highly responsive to changing needs. This also allows maintenance to be conducted on one module while the rest of the system continues in operation. Properly executed, this modular design also minimizes the vulnerability of the system to mechanical failures.
• This process can produce advanced secondary, or even teritiary, quality effluent. A properly designed system can routinely provide a significant reduction of total nitrogen content, a significant advantage if total nitrogen is part of the effluent set for a discharging system or is determined to be critical to protecting groundwater resources in a soil dispersal system.
• Maintenance processes, for both the filter bed and the "peripheral" equipment, are fairly simple and straightforward.
• Clogging of the filter bed, the major mode of process failure, is generally a very slow and gradual process, affording the operator the luxury of responding essentially at his leisure. In a properly designed system, bed cleaning is accomplished using readily available equipment in fairly short order, so "down time" is minimal.
• Sludge management for this system is not a time-critical operation. Most of the sludge is retained in the septic tank(s) used for pretreatment. As detailed previously, these can essentially be pumped when convenient. The remainder of the sludge is removed during the bed cleaning process. As noted above, the timing of this cleaning is also very flexible.

Disadvantages of sand/gravel biofiltration systems include:

• For larger systems, the hydraulics of flow distribution to the filter bed can become rather problematic. However, for the scale of systems required for Cabot and Marwood, even a single large-scale system for each community would be quite workable.
• For larger systems, land requirements for the filter beds may be a problem. This would not appear to be a problem for Cabot and Marwood, however.
• Even though the basic technology pre-dates activated sludge by about 50 years and the "modern" design concepts are very widely reported in the literature, this technology is still generally considered to be "alternative"-or even "experimental"-and the regulatory, design and construction communities are generally unfamiliar with it.
• Since septic tank effluent is sprayed over the filter bed, odors must be contained. For small-scale systems, this is typically no problem, as the filter beds are typically contained within tanks or similar covered containments. For larger-scale systems, however, covering of the beds may be a significant cost item. (Note: Covering of the beds is highly recommended in any case to minimize need to remove plants that grow from wind-blown seeds and to exclude an additional hydraulic load from rainfall, and in the climate of western Pennsylvania, to provide freeze protection.)
• If an ammonia nitrogen limit is imposed on a discharge, cold weather can be problematic, perhaps requiring a more "sufficient" cover over the beds, further increasing costs.
• This technology by itself cannot attain low phosphorus concentration, a problem if that parameter is included in the effluent set for a discharging system.

Overall, a sand/gravel biofiltration system would be an excellent choice for treatment systems to serve wastewater management needs in and around Cabot and Marwood, whether as individual home systems, small-scale collective systems, or at the end of the pipe in a large-scale collective system. The major question is the regulatory acceptability of the technology and the arrangements that must be made for effluent dispersal relative the final effluent quality that the regulatory system would concede to this technology.

4.2.2 Intermittent biofilters using other media

An "emerging" technology is a biofilter bed employing other types of media. These include textile filters and foam filters. These filter beds are simply inserted into the same biofiltration concept as used for sand/gravel filters. Their advantage is that it appears they can produce similar (or better) effluent quality in a significantly smaller filter bed than is required for a sand/gravel filter. Thus, assuming they perform adequately, systems using these filter beds would have all the advantages of the sand/gravel biofiltation system, while the disadvantages related to land requirements, flow distribution, and costs of covering large-scale filter beds would be reduced. At this point, it is unknown how total cost would compare to a sand/gravel biofiltration system, and it is unknown what standard of proof for performance of the system would be required by the regulatory system. If costs are competitive and performance can be adequately verified, this type of system would also be a very good candidate for wastewater management systems in Winfield Township. Again, however, an unknown is the arrangements that must be made for effluent dispersal relative to the final effluent quality that the regulatory system would concede to this technology.

4.2.3 Trickling filters

This technology is another form of biofiltration, one that operates at much higher loading rates so that a much smaller filter bed area is required for any given flow. However, being more heavily loaded and employing much coarser media, the system is more prone to "upsets" due to varying loading or toxics in the wastewater. Also the filter media continually sloughs solids, so that a secondary clarification process is needed after the filter. These characteristics indicate that this technology is typically more suited to larger systems than it is to systems serving one or a very few homes, although some small-scale "packaged" systems embodying this technology claim excellent performance. At least one of them claims to also accommodate high strength wastewater very well, so this may be a technology that would be advantageous for commercial installations, such as restaurants, within an on-site or small-scale collective strategy. It is unknown at this point how the regulatory system views these performance claims. Subject to regulatory approval and to being cost competitive, this technology may also be worthy of consideration for use in Winfield Township.

4.2.4 Activated sludge

There are several forms of the activated sludge process, and all these variants will not be reviewed here. Each one is more or less prone to the disadvantages listed below; however they are all vulnerable to them to some degree. The advantages of this process include:

• It is THE mainstream technology so, despite its weaknesses, it is generally acceptable to the regulatory system and is well known to designers and contractors.
• There are many products on the market that allow this technology to be implemented essentially "off the shelf". These products range from single-family home systems up to large-scale plants that could serve all of Cabot and Marwood.
• For larger scale systems, this technology is somewhat less land intensive than some other options.
• While, with proper modifications, this process could be used with an effluent sewer system, it is typically used with a sewer system that delivers all the wastewater solids to the plant, thus centralizing the sludge handling process.

Disadvantages of activated sludge processes include:

• The process is inherently unstable. It depends for treatment upon very few trophic levels of organisms, living in concentrations far higher than found anywhere in nature.
• This unnatural environment must be maintained by input of energy, which is critical to maintaining process integrity, and by close attention to operating conditions over the short term.
• Thus the process is prone to "upsets" from many causes, including flow variations, untimely operator intervention, and mechanical problems. Once "off track" it typically takes some time for the process to return to normal, during which poorly treated effluent continues to be produced.
• There is not even an operating theory for activated sludge that does not have to assume steady-state flow, so unless flow into the treatment unit is equalized to make it uniform, the system is operating "off theory" to begin with. This would indicate that performance would always be problematic and operation is largely based on empirical principles.
• As implied by the above, this process requires diligent oversight by a trained operator. The operations and maintenance activities are not simple and straightforward.
• Especially in larger-scale systems, to which this process would be more suited because of flow variation and cost of adequate oversight in dispersed smaller systems, the quality of effluent depends on proper operation of a secondary clarifier. Even with diligent oversight, "sludge bulking" in clarifiers is a common problem.
• Sludge handling can be a significant logistical problem. Sludge must be removed from the process as dictated by the needs of the process, typically on a time scale measured in hours, or the process will degrade.
• Without special modifications to the process which may increase the complexity and/or the volume of sludge produced, activated sludge processes do not significantly reduce total nitrogen concentration or produce low phosphorus concentrations.
• Capacity of an activated sludge plant cannot readily be expanded without adding parallel trains or major reworking of components. It cannot be readily expanded in small increments of capacity. Therefore, larger capacity expansions are typically executed to provide for flows expected many years into the future, so that considerable investment is expended that would not be fully utilized for years to come.
• In regard to the above point, significant underloading of some activated sludge processes is problematic, further confounding planning of plant expansions.
• The system contains moving parts that operate in a very harsh environment. Therefore service life may be short relative to other technologies.
• Energy costs to run this technology are high.

The many disadvantages of the activated sludge process indicate that it is best employed in large, base-loaded plants where the land efficiency of this technology is critical, and the community's budget provides for a crew of well-trained operators who can actively attend the plant 24 hours every day. For plants the size of those projected for Cabot and Marwood, this is a relatively poor choice for treatment technology even under the large-scale collective strategy, and becomes an even poorer choice relative to other options for smaller plants to serve the other strategies. Its only saving graces are that it would likely be somewhat easier to run through the regulatory process and the initial cost may be attractive relative to other options, although life cycle costs would be relatively high.

4.2.5 Aquatic/wetland systems

This technology, usually called constructed wetlands, can be divided into two broad categories:

• Processes which attempt to duplicate natural wetland ecosystems, wherein treatment is affected by routing flow with a free water surface over a substrate in which wetland-adapted plants are cultivated.
• Processes which attempt to mimic and improve upon the natural ecosystem functions in an artificial physical environment, wherein treatment is affected by routing flow through a porous media, on the surface of which wetland-adapted plants are cultivated.

Either type could be considered for a large-scale treatment plant, but it is to be expected that an open free water surface in close proximity to residences and businesses would not be readily accepted, so only the subsurface flow wetland could be entertained for use in on-site or small-scale collective strategies. Unless of course, the unit is enclosed in a greenhouse. At least one commercial system employing that strategy is on the market. The major advantage of this technology is that it is very simple in concept to construct and to operate. Unless recirculation concepts are employed, supplemental aeration is required, or effluent must be pumped to the wetland location, the treatment system operates without external energy inputs other than solar energy. Thus it may be relatively inexpensive to construct and to operate and maintain.

There are several potential disadvantages to this technology, however. These include:

• While this system is conceptually simple, a wetland is a complex ecology. Attention to establishing a healthy and "balanced" ecology is critical to long-term performance of the system.
• The technology is not well known to the regulatory system or to designers and construction trades.
• The performance history of the technology is varied. While this may be due in part to inexpert design and/or construction, it also reflects the natural variability of this complex ecosystem.
• For subsurface flow concepts at least, nitrogen reduction-or even low ammonium nitrogen levels-are typically not attained unless supplemental aeration is supplied or recirculation concepts are employed, increasing the complexity and cost of the system.
• Unless the wetland is covered, it will intercept rainfall and route this additional hydraulic load to the effluent stream. This may be highly problematic if effluent is routed to soil dispersal fields, since this would occur at the same time the soil is already wet.
• The system is vulnerable to disease, predation, etc., which can compromise or destroy the wetland ecosystem. Recovery from these problems typically requires considerable time, during which substandard effluent would be produced.
• In the climate of western Pennsylvania, there would be considerable seasonal variability in performance. The system would have to be sized for winter performance, which would require it to be considerably "oversized" for the rest of the year. Even so, with the plants going dormant, degraded performance would probably be experienced in the winter.
• While creative design can enhance nutrient removal by creation of appropriate ecosystem niches, some part of nutrient removal capability will be via plant uptake, implying that plant material must be periodically removed if nutrient reduction is required. Plant removal may constitute a considerable maintenance liability.

While this technology has an obvious charm as a "natural" treatment system, it has an uncertain performance potential and regulatory status. While a wetland system would quite likely produce a sufficient effluent quality for soil dispersal, interception of rainfall by the wetland makes this strategy highly problematic. If the wetland is covered to preclude this problem, that would increase the construction and maintenance costs. Subject to regulatory acceptability, it appears this technology could be considered for Cabot and Marwood under the large-scale collective strategy, but other options appear preferable for on-site and small-scale collective strategies.

4.3 Soil Dispersal System Options

For all but the large-scale collective strategy, soil dispersal would be the likely means of routing wastewater system effluent back into the hydrologic cycle, and even the large-scale strategy could employ soil dispersal if desired. It must be understood that in the wastewater management process, there is no such thing as "disposal"-the effluent does not go "away" and it doesn't stay where it is placed. The process of distributing effluent into the soil is dispersal. Its purpose is to route the water back into the hydrologic cycle in a manner that allows the soil system to provide adequate treatment to remove remaining pollutants before the effluent reaches a limiting condition. This is that point in the soil profile where no significant further treatment can be expected no matter how far the effluent moves from there. A review of the removal/assimilation mechanisms operating in the soil system shows that, for all pollutants of concern, three factors will enhance the effectiveness of these mechanisms: (1) shallow dispersal in the biologically active soil horizon, (2) uniform distribution over the entire dispersal area using a dose/rest loading cycle, and (3) low areal loading rates. The options for soil dispersal systems are reviewed below.

4.3.1 Drip irrigation fields

This technology, loaded at a "proper" rate, is the ultimate practical embodiment of those three factors. Water oozes out of emitters at a very low rate, typically about one gallon per hour or less, providing a very slow and uniform wetting of the soil. Experience in Minnesota has shown that, with proper precautions in the design and construction, drip lines can be installed shallowly in the root zone and not incur significant freezing problems, so shallow dispersal can be practiced with this technology in the climate of western Pennsylvania. Since installing drip lines requires little excavation, it may be fairly cost efficient to install, so providing larger fields (lower areal loading rates) using this technology is likely to be more affordable than for other options. If soil depth is severely limited, drip lines can be installed on the existing soil surface and covered with fill, or even installed up in the fill layer to provide more soil depth. Routing of drip lines is very flexible, allowing them to be installed around existing trees and shrubs. Thus, drip irrigation makes practical the use of spaces for a dispersal field that might not be usable with other methods. While considerable irrigation benefit can be provided during the growing season (assuming of course that the field area is covered with plantings that would benefit from irrigation), the field must work like a "drainfield" once the plants go dormant for the winter, with more effluent being lost to deep percolation rather than to evapotranspiration.

The major problem with this technology is that it is fairly unfamiliar to regulators, designers and installers. Regulatory acceptability is uncertain at this point, as the regulations for drip irrigation contained in DEP's "Alternate and Experimental Systems Guidance" is of questionable relevance. The design requirements that would be imposed upon this method are therefore undetermined at this point. Soil depth between drip lines and a limiting condition should, of course, be related to the degree of pretreatment provided prior to dispersal in the drip field. At present, drip irrigation as might be proposed in practical collective systems or for use with treatment concepts not addressed by existing regulations in systems of any size might be considered as an "experimental" technology, a wholly unacceptable status for use in a municipal wastewater management system. This barrier must be addressed and surmounted if drip irrigation is to be used in a public wastewater system. For limited application under an on-site strategy or for on-site systems within a small-scale management strategy, experimental applications may be acceptable.

4.5.2 Narrow-trench low-pressure-dosed fields

This technology has been described as a "pseudo-drip" system. It consists of narrow trenches containing a shallow bed of gravel and a perforated PVC effluent distribution lateral. The trench acts as a "line source emitter" but there is no control over the wetting rate as there is in true drip irrigation. A "slug" of effluent is pumped into the trenches each time the field is dosed. When sufficient matric potential exists in the surrounding soil, water will be "wicked" out of the trench into the soil around it where it can be dissipated by evapotranspiration; otherwise much of the water will be lost to deep percolation. Practicality of construction generally dictates that trench spacing is greater than typical drip line spacing, so uniformity of distribution is lower even without regard to the lack of control over wetting rate. The trenches can be installed at any depth, but treatment effectiveness is enhanced by keeping them as shallow as practical, as noted above. If existing soil depth is limited, the trenches can be installed at the existing surface, or even up in a fill layer. Routing of lines is less flexible than with true drip irrigation because of the larger trench and use of PVC rather than highly flexible polyethylene pipe, but it still may be practical to utilize spaces that could not effectively be used for "conventional" drainfields. The larger trench and need for gravel around the lateral pipes indicate that this type of field would be more expensive to install than a true drip irrigation field of the same size.

While the basic idea of this technology has been in common use since the early 80's, it appears that it has not been adopted as a "standard" drainfield design in Pennsylvania. Thus its regulatory status is as uncertain as true drip irrigation, both in regard to approval of the method and to the soil depth requirement between the infiltrative surface and a limiting condition relative to the degree of pretreatment provided. These matters must be addressed in order to use this technology as part of a public wastewater system. Limited use of this technology under experimental approval may be acceptable under an on-site management strategy, or for on-site systems within a small-scale management strategy.

4.5.3 "Conventional" low-pressure-dosed fields

The "conventional" low-pressure-dosed field currently recognized in Pennsylvania distributes effluent evenly over the field area just as in the previous option, but the laterals are installed in a bed of gravel covering the entire field area rather than in a small gravel envelope in individual trenches. This type of construction dictates that, except at the edges and to the extent that roots penetrate the gravel bed, evapotranspiration is completely negated as a means of dissipating the effluent, meaning that practically the entire flow would exit via deep percolation at all times. This design is therefore relatively sub-optimal in regard to enhancing the removal/assimilation mechanisms acting in the soil system. This type of field can be installed in-ground or, if soil depth is limited, it can be installed at-grade with fill soil mounded over the gravel bed.

The design is familiar to the regulatory system, so approval of the design should therefore be fairly straightforward. However, it has generally been applied only to dispersal of septic tank effluent, for which the soil depth requirements have been specified. It is unclear at this point how much soil would be required between the infiltrative surface and a limiting condition relative to the degree of pretreatment provided prior to dispersal. Thus the utility of this method to strategies which employ pretreatment is unknown at this point.

4.5.4 Gravity-dosed fields

This is the "conventional" drainfield. Whether it is installed using a large gravel envelope around a lateral pipe or using leaching chambers, the function is similar. Uniform distribution over the field area is never achieved, even in home-sized systems, and this problem is exacerbated as the field size increases. This technology should only be considered for individual home systems, and then only when a site is suitable for dispersal of septic tank effluent in this type of field-in Pennsylvania, that appears to mean 48 inches of "suitable" soil is available between the trench bottom and a limiting condition. However, even then this method is circumspect if nutrient loading is of concern, unless enhanced pretreatment is provided to remove nutrients before dispersal.

5. GENERAL DISCUSSION OF MANAGEMENT SYSTEMS

While the State of Pennsylvania provides guidance on forms and structures for managing on-site systems (called "onlot" systems in official language), this guidance does not appear to recognize that the overall management system might include any combination of on-site systems, small-scale collective systems, and large-scale collective systems that are found to be most effective and appropriate to the circumstances of each community or neighborhood. This is likely a product of a prevailing view that wastewater management is a "dichotomy"-either one has an on-site system contained entirely within the boundaries of the lot it serves, or one hooks up to a "sewer system", with that term generally defined very narrowly to mean what is denoted in this report as a large-scale collective system. To most effectively and cost efficiently address the wastewater management needs over the whole of Winfield Township is likely to require the use of on-site systems and small-scale collective and/or large-scale collective systems, depending on the choices made for situations that require a collective solution. Thus, some of the "hardware" is likely to be decentralized, and a management system may need to be formulated to deal with this situation. This section provides a general introductory overview of options for the structure, form, and function of the management system required to run a system in which the "hardware" solutions may not dwell exclusively on one side or the other of that dichotomy.

5.1 Management System Functions

A management system must, above all else, assure that technologies appropriate to the constraints encountered on each site are implemented and that they are properly operated and maintained. In pursuit of this "bottom line" goal, overall management of the entire wastewater system entails several discrete functions. These include:

• Planning - The necessity for various actions-both management and technological-must be established, and rules to assure their execution must be promulgated. The agency or agencies with responsibility for each aspect of management must be identified and their capabilities evaluated. Other planning items may include an operations plan, a financial plan, an implementation plan, and coordination with land use planning.
• Site evaluation - The importance of this function to the choice of proper technology is obvious. The management system must enforce and facilitate these activities.
• System design - Also obvious is that the chosen wastewater system must be properly designed, based upon the site constraints, if it is to function as envisioned. The management system must enforce and facilitate the design process. This may involve development of design standards, provision of design guidance, review and approval of designs, or complete design responsibility.
• Installation supervision - The best designs will go for naught if they are not properly installed. The management system must provide for inspection of system construction, and it must also assure that the persons performing the work are qualified and competent to address the technological solution proposed.
• Operation and maintenance - Proper execution of this function must be assured if the system is to continue to function as desired. Operations and maintenance functions include timely pumping of tanks and proper handling of septage, executing treatment and dispersal system repairs when needed, and ensuring that all system components-such as pumps and filters-remain functional. The management system must enforce and facilitate the consistent performance of these activities.
• System inspection - To assure that operations and maintenance procedures continue to be properly applied, periodic inspection of systems must be provided for by the management system. The frequency and detail of these inspections would be largely determined by the nature of the technologies employed.
• Financing - Fiscal resources needed to carry out all functions of the management system must be assured. The management plan must incorporate adequate funding for the agency or agencies carrying out various management functions. This may involve setting of user charges, design fees, inspection fees, etc.
• Water quality monitoring - Feedback on actual performance is necessary to evaluate if the technological options being implemented are in fact minimizing water quality degradation. The management system should provide this feedback through a program of water quality monitoring and analysis.
• Public education - To rally support for the use of the necessary and proper technological solutions-especially when they may be more costly than conventional practice-and for funding of the required management activities may require education of the public on the benefits of a "better" management system. Also, depending on the technologies employed, the users of these systems may need to be educated on their capabilities, limitations, etc.
• Program coordination - The aspects of management which are carried out by different "players" must be coordinated to produce the most effective and efficient management program.

All these activities must occur in order to properly manage decentralized on-site/small-scale systems so as to avoid water quality degradation and to maximize cost efficiency of the entire system. Those functions which are not explicitly assumed or assigned by an organized management entity will fall by default to system users, installers, etc., on an ad hoc basis, or they will be neglected.

The above descriptions indicate that "players" other than the Township may be involved in the complete management system. There are alternative organizational schemes for accomplishing the management functions. For example, under the present system of on-site wastewater management, the private sector and the responsible governmental entity jointly conduct site investigations, the private sector executes system designs, government agents review designs and issue approvals, the user is solely responsible for financing the project, and so on. Thus, the form, content, powers and duties of any management program are subject to how many of these functions each management entity chooses to assume. This leads to consideration of options for the management structure.

5.2 Management Structure Options

Two basic options for the management structure can be identified. One is to continue with the current structure, with a Sewage Enforcement Officer (SEO) hired by the appropriate local governmental agency continuing to assume responsibility for assuring proper site inspection, system design and installation, and ongoing surveillance, and with these functions continuing to be executed by the private sector. To accommodate the technologies and organizational strategies that may be proposed for use in Winfield Township under this structure would require the promulgation of new regulations to mandate and/or encourage the desired actions. That would entail enacting the appropriate rules and regulations, making contracts necessary to execute them in practice, obtaining authority not currently granted (e.g., right of entry for ongoing inspection and monitoring), hiring personnel technically competent to deal with the proposed technologies, and providing the appropriate policy direction as required to implement the new management functions and/or strengthen existing ones. It would probably also imply some consideration of how to fund the new or revamped activities.

It is questionable, however, whether this structure can properly address collective systems. And at this point there is no indication that the existing institutions would be willing to take on an expanded role. The other basic option for a management structure is to create a management district which may partially or completely replace the activities of the SEO's and/or provide functions not currently addressed in an organized fashion. Issues impacting upon how such a district is organized are outlined below.

5.2.1 Form and Powers of a Management District

A management district for on-site/small-scale wastewater systems may be a governmental body, a quasi-governmental body, or a private entity. It must be determined if townships in Pennsylvania are granted adequate powers to execute or assign (oversee the execution by private parties) all the required management functions. Separate bodies, such as a sanitary district, may also have the required powers. Private water and sewer suppliers or home-owner's corporations may provide some of the management functions through contracts, articles of incorporation and/or deed restrictions.

Whatever its form, the management entity should be guaranteed permanency and continued fiscal solvency. It should also possess specific rights, including:

• Authority to own, purchase, lease and rent both real and personal property;
• Right of access to the systems it governs by covenant, ordinance, or other suitable instrument running with the land;
• Eligibility for loans and grants for construction of facilities;
• Ability to enter into contracts and to undertake debt obligations, either by borrowing or issuing stocks or bonds;
• Authority to set and collect charges for system usage and/or oversight, set the value of such benefit, and assess or collect the cost from each property owner that is benefited;
• Power to make rules and regulations regarding use of on-site/small-scale systems; and
• Power to require the abatement of malfunctioning systems.

5.2.2 Functional Organization of a Management District

The choice of management entity is further predicated upon a definition of the management functions it must perform. Two distinct types of districts can be entertained:

• Maintenance districts, which only control installed systems, assuring their continued proper function, while leaving the governance of system choice, design, installation, etc., to the usual permitting processes; and
• Total management districts, which oversee design, etc., as well as assuring continued proper functioning.

Under a maintenance district, site inspection and system design, permitting and inspection would be accommodated under current procedures. However, if the technological solutions being proposed were outside of existing codes, each potential user would have to hire consultants conversant with the options being proposed to advance the permit application, including design of the system and justification for that design. Further, it would be left to users to independently "broker" any arrangements for small-scale collective systems or off-site facilities.

Under a total management district, the management district may be able to address all these processes on behalf of the users. If this management district has the powers outlined previously, it would also be capable of making arrangements for collectivizing treatment and/or dispersal systems. There may be many situations where this strategy would allow "on-site" management for sites not capable of accommodating an environmentally sound dispersal field and/or where this strategy would provide more cost efficient management.

Ownership of system hardware presents another choice for the functional organization of the management system:

• The systems may be privately owned, but publicly managed. The owner would pay user charges to the management district, which performs the necessary surveillance and monitoring, and perhaps also performs maintenance functions for the owner. System rehabilitation or replacement would usually be the owner's responsibility under this mode. This scheme could be employed equally well in either a maintenance district or a total management district.
  
  
• The systems may be publicly owned and managed. All management activities, including rehabilitation or replacement, would be performed by the management district. Various arrangements for funding these activities could be entertained-e.g., a "regular" user charge for routine surveillance, monitoring and maintenance, and a "special" assessment for major repairs or system replacement. While one could envision a system where the owner bears responsibility for original construction of the system, then turns it over to a maintenance district, this mode is much better suited to a total management district.

Various "hybrids" of these general scenarios are possible, of course. For example, the management entity might specify designs, oversee installation and provide surveillance, monitoring, and maintenance-and perhaps even have title to the completed system, but require the owner to independently engage and pay contractors for all construction. Ownership could also be situational, with individual on-site systems continuing to be privately owned, with only a public oversight function, and collective systems being both owned and overseen by the management district.

5.3 Options for Execution of Management

Note that, regardless of the decisions made regarding functional organization, the management district may accomplish any or all of its functions either directly or by contracting with private-sector entities to execute the activities. An example is pumping of septic tanks. A management district may assume responsibility for timely pumping of septic tanks, but contract the pumping to a private company. Or the management district might only monitor sludge depth and require the system user to contract directly with a private company to pump the tank at the appropriate time. This illustrates that there are not only options for the organization and powers of a management district but that there are options for how the management district executes its functions.

The choice of district type and scope of authority has implications for user costs, due to the type and extent of administrative system and labor force which must be established. If it is assumed that all management functions must be supplied-and paid for-regardless of whether responsibility is left with the owner or is assumed by the management district, then there would be a tradeoff between what the owner pays for directly vs. what he/she pays for indirectly through user charges, permit fees, inspection fees, etc. One's feelings about the efficiency and quality of publicly sponsored activities vs. regulated private sector activities will undoubtedly influence which approach is preferred.