Memorandum
City of Lawrence
City Manager’s Office
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To: |
Dave Corliss Interim City Manager |
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From: |
Debbie Van Saun Asst. City Manager |
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cc: |
Dave Wagner, Asst. Utilities Director |
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Date: |
March 7, 2006 |
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Re: |
Summary from 030106 PAC meeting |
On March 1, 2006, the Public Advisory Committee (PAC) participated in a public meeting that included the following agenda items:
§ Presentation by Jonathan Todd of the Eco Machines (formerly Living Machine) technology
§ Question/answer period from public, Peer Review Group, and PAC
§ Discussion by PAC with goal of submitting recommendation to City Commission
The memo serves as a summary of the comments provided and activities accomplished during this public meeting.
Background Information
As part of the public participation and outreach component of the Wakarusa Water Reclamation Facility project, the Mayor appointed, with City Commission approval, a Public Advisory Committee comprised of representatives holding a variety of perspectives (e.g. regulatory, environmental, property interests, etc.). The mission of this group is to guide the public participation process by serving as the voice of the community throughout the development of the project, providing input regarding site utilization concepts and appearance related to the facility. The PAC has been meeting on a regular basis to research the suitability of various sites prior to the initiation of land acquisition negotiations. Nearing the end of that process, some members of the PAC requested, and the City Commission approved, an opportunity to educate the community about the Edo Machine technology as it might relate to a municipal application in Lawrence. To that end, staff and members of the PAC made arrangements for Mr. Todd’s presentation, as well as the other items included in the aforementioned agenda.
The peer review group concept was developed early in the project to provide a “sounding board” for the professional review of any issues that might come up during the course of the project. The credentials of the peer review group utilized for this issue are attached.
Public Meeting Discussion & PAC Recommendation
Mr. Todd’s presentation is available on the City’s website. The following reflects a summary of the minutes taken at the public meeting during the question and answer period and the subsequent PAC discussion:
o Pretreatment would be needed with the Eco Machine technology in certain situations, just as it is needed in conventional treatment.
o For some toxic elements, Eco Machines are robust for small scale but on a large scale, any advantage is lost.
o Space needs for Eco Machines – we received a variety of estimates on this topic; it appears to be an issue that would be addressed in the design phase. There was agreement that outdoor wetlands require more space than conventional treatment and this space could be reduced by considering a contained wetland.
o The Eco Machine technology would be designed for the “worst case scenario” in regards to climate.
o The plants involved in the Eco Machine technology, when used in a small system (defined as under 100,000 gallons per day) work reasonably well in nutrient removal, provided the nitrogen and phosphorous levels are low. In larger systems, the plants may be more decorative in nature and do not significantly contribute to the treatment process.
o Johnson County has done a considerable amount of planning and analysis on the topic of centralized versus decentralized systems. Johnson County Wastewater concluded that decentralization was not an appropriate approach because it encourages leap frog development and the potential for additional discharge permits and associated water quality monitoring and reporting.
o The KDHE representative on the peer review committee indicated an interest in Eco Machine technology for small communities across Kansas in lieu of typical wastewater lagoons.
o Eco Machines are typically associated with applications where the amount and strength of flow is consistent and are not well suited for municipal systems with Inflow and Infiltration (I/I) and less reliable strength flows.
o In terms of scalability, contained wetland treatment in a municipal application isn’t feasible for systems greater than 500,000 gallons per day.
o El Dorado is using an approach that combines a mechanical plant for daily flows and wetlands for excess flow treatment during significant rain events.
o Again addressing scalability and the Eco Machine technology within a greenhouse facility, there are a very small number of plants that can produce roots two to three feet long, which is needed for the process. Plants need to be in shaded areas and the heat dissipation issue is significant within a greenhouse. OSHA requirements for workers in the greenhouse would also be a concern due to heat exposure.
o Both of the experts in the Eco Machine technology were not supportive of using the technology in a 7 MGD facility application.
o If used in an industrial area or for small developments, the Eco Machine technology may be more appropriate.
o After additional PAC discussion, there was consensus to continue pursuing a centralized system that allows for a review of alternate process means that would fit in the applicable footprint. This approach ended up being the recommendation that was acceptable to be forwarded to the City Commission.
o Comments throughout the PAC discussion following the presentation and question/answer period were consistently favorable and positive regarding this opportunity to learn more about the Eco Machine technology.
City Commission Action
City Staff and members of the PAC request the City Commission to receive the PAC recommendation: For the Wakarusa Water Reclamation Facility project, continue to pursue a centralized system for wastewater treatment facility for discharge to the Wakarusa River. During the treatment analysis phase, direct Black & Veatch to consider and review any alternate process means (e.g. pre-treatment and/or post treatment) that would fit in the applicable footprint for the selected site.