Memorandum. To: From: Date: July 10, Cc: Re: Introduction. to control. This time. primarily. excavated

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1 Memorandum To: From: Date: Cc: Dave Taylor, Madison Metropolitan Sewerage District Rob Montgomery July 10, 2012 Kevin Connors, Dane County Peter Hughes, USGS Re: DRAFT description of Alum treatment demonstration project at the Dane County / Endres Farm site Introduction This memo describes a proposed project at the Dane County/Endres Farm site that will demonstrate the effectiveness, cost and logistical issues associated with in stream treatment of agricultural runoff to control phosphoruss export using liquid aluminum sulfate (alum). The site is located in the Six Mile Creek watershed west of the Village of Waunakee (seee location map). The watercourse to be treated and monitored drains highly productive tilled land, including areas that have drain tiles. The watercourse discharges to the Waunakee Marsh, and from there to Lake Mendota. The proposed project would be conducted from approximately October 2012 through May This time period will provide dataa on control of runoff phosphorus content during the fall as well as the snowmelt and spring runoff seasons, whichh is when thee bulk of phosphorus load is often deliveredd to streams from agricultural lands in southern Wisconsin. The project could be extended to collect data over a longer time period if desired after initial results are obtained. Alum treatment as a potential element in watershed phosphorous control Aluminum sulfate, Al2(SO4)3, commonly called alum, has been used in the treatment of water and wastewater for over 100 years. Alum has been used since the 1970s forr control of nutrients in many natural lakes, including several in Wisconsin. Alum treatment of urban storm water runoff has become an established storm water quality retrofit option, with more than 25 years of experience, primarily in the Southeast. The potential value of alum treatment of both urban and rural nonpoint source pollution has been identified in recent work as an option for control of nutrient input to the Yahara chain of lakes in Dane County. The control of rural nonpoint source nutrient runoff to the Yahara lakess is of critical importance, due to the relatively high loading of sediment and phosphorus derived from the agricultural watersheds draining to the lakes. Although many of thesee streams are natural, many others are excavated

2 Page 2 channels, often receiving both surface water runoff and discharge from agricultural drainage tiles. It would be valuable to gain local on site experience on the cost and effectiveness of alum treatment in these drainageways. Demonstration project objectives 1. Conduct a demonstration of in stream alum treatment to reduce phosphorus loading in an agricultural drainageway over the fall, winter and spring months that typically produce the bulk of phosphorus export in agricultural watersheds. 2. Draw initial conclusions regarding logistics, effectiveness and cost of alum treatment as an option for rural nonpoint source nutrient load reduction. 3. Recommend best next steps including possible extended duration of the demonstration project to develop policy and technology options for in stream treatment for nutrient loading in drainageways. Value of Demonstration project in this watershed The chemistry of nutrient control using alum is well known, as are the mechanical systems for introducing elements of the water column and predicting dosing rates to achieve load reductions. However, there are several important watershed specific reasons why conduct of this project in the Six Mile Creek watershed would be valuable: It would provide specific demonstration of the use of alum dosing for in channel treatment of dissolved phosphorus, in a drainage ditch that is very typical of farm drainage ditches in the Yahara River watershed, and throughout southern Wisconsin; The project would provide practical experience information on dosing of alum during Wisconsin winter conditions. Cold weather applications of alum treatment for nutrient reduction are not as frequently documented as experience in warmer climates; and Perhaps most importantly, this project would provide data and the opportunity to go on walking tours for the public, as well as stakeholders and agency representatives, to understand system components, and to directly observe visual or chemical condition in the drainageway to address the qualitative concerns that could arise regarding this treatment approach. Applicability and transferability of results This project will produce quality data on the effectiveness of in stream treatment for phosphorus in agricultural runoff. The project setting is typical of the topography and soil conditions that are encountered in the watersheds tributary to the Yahara chain of lakes in Dane County. Further, the project setting is also typical of drainageways in agricultural lands in most of the glaciated portion of

3 Page 3 southern Wisconsin in terms of topography, soil parent materials, tillage practices, and the presence of drain tile. Details of demonstration project location and layout A good location for a rural drainageway alum treatment demonstration project is on property owned by Dane County north of Hyer Rd. in the Town Springfield (see the attached figure). This property is owned by the County and operated by the Endres farm, and has an active program of research on field runoff and drain tile water quality, as well as a plan for planting and management of harvestable biofuel. The United States Geological Survey (USGS) is actively maintaining data logging and telecommunications equipment installed as part of a project and supporting runoff and tile drain water quality data collection. The watershed draining to this location has an area of approximately 6.5 square miles. Runoff from this subwatershed drains into the Waunakee marsh, exiting the marsh as a tributary of Six Mile Creek, which discharges to Lake Mendota. The demonstration project would consist of equipment to measure stream discharge and to apply alum treatment for nutrient (primarily phosphorus) stabilization using a flow proportional dosing system. The alum would treat dissolved and particulate phosphorus in a treatment reach of the drainageway north of Hyer Rd. (see figure), and discharge would be sampled for water quality parameters at or near Hyer Rd., as well as downstream. The alum would be delivered to a tank near the road, and monitoring and treatment system data would be collected and transmitted using the data loggers and telecommunications equipment already installed by the USGS. Demonstration project team The demonstration project team would be led by Montgomery Associates: Resource Solutions, LLC, based in Cottage Grove, supported by Dr. Harvey Harper of Environmental Research and Design, Inc., Belle Isle, Florida. The project would also be supported by USGS personnel based in Middleton. Project elements Project startup bench scale testing and confirming demonstration project design Collect water samples to characterize nutrient and physical chemistry parameters that will be important in confirming the treatment dosing. Use on site runoff samples to conduct bench scale jar tests to confirm appropriate alum dosing rates given water quality and hydraulic conditions at the Endres Farm. Confirm alum dosing and monitoring equipment plan, and develop a brief projection of anticipated treatment effectiveness and cost. Confirm demonstration project duration (expected to be approximately 7 months) and cost, including participation by supporting parties such as the USGS and Dane County personnel.

4 Page 4 Document water quality analysis and project description in a brief report for discussion with local agencies and project sponsor. Demonstration project operation Install the monitoring system in coordination with USGS to take advantage of instrumentation already on site. This is expected to include samplers upstream of the dosing location and downstream of the treatment reach. The anticipated layout of the project is shown on the attached figures. Install alum dosing equipment and storage tanks. The storage may be provided by a leased tanker parked temporarily adjacent to Hyer Rd. The dosing system is expected to include a chemical dosing pump and controls, connected to the USGS data logging system. Conduct the monitoring program to collect data for a period of base flow as well as several rainfall runoff events. This work will include monitoring the alum dosing system, collecting and analyzing samples, and monitoring the system electronically via the telecommunications system installed by the USGS, as well as periodic site visits. Maintain quality control for collected data on discharge and treatment remotely using data logging capabilities as well as using periodic on site visits. Review quality control and results of water quality sample analysis has data is developed. Analysis and reporting Documentation of the demonstration project, emphasizing water quality results. Projection, based upon project results, of the systems required and approximate cost of a watershed scale in stream alum treatment nutrient control system. Recommendations for additional studies that may be required to define in stream treatment feasibility. This recommendation will specifically address the value and logistical issues associated with extending the demonstration project at the Dane County/Endres Farm site. Costs Costs at this time are estimates, to be confirmed after bench scale testing Project startup including runoff sampling and analysis, and bench scale testing to confirm alum dosing rate and equipment, field survey of monitoring locations, confirmation of monitoring equipment selection and agency coordination, brief memo describing results, meeting including Harvey Harper to discuss and confirm the approach. Equipment procurement and installation, including flow meters and samplers, data logger connections, alum dosing including pipe, pump, controls, and alum tank on site. $20,000 45,000

5 Page 5 Demonstration project operation for 7 months, including periodic alum purchase and supply to on site tank, sample collection and analysis, and monitoring program operation. These costs will be confirmed based on bench scale testing, and could be reduced by participation of County personnel. Part of the variability of these costs is the required volume of alum used for treatment, which will depend upon runoff volume during the monitoring period. $60,000 80,000 Reporting, documentation, recommendations, meetings $20,000 Total estimated cost $145,000 $165,000 Note: the costs tabulated above do not include the cost of support from the USGS for integrating and supporting the data collection program for the demonstration project with their ongoing agricultural runoff monitoring, logging and telecommunication system. These costs will be estimated in the next several weeks. Financial support for the demonstration project We are actively pursuing funding for this project from the variety of stakeholders. The status of funding commitments for this project is described on the attached table. Questions Please contact Rob Montgomery at Montgomery Associates: Resource Solutions, LLC with any questions on this project description. Figures: Project funding commitments Project layout Regional setting and additional sampling locations

6 Page 6 Status of funding commitments as of July 10, 2012 Alum treatment demonstration project at the Dane County / Endres Farm site Funding Partner Funding Target Status Dane County $20,000 currently under consideration Yahara WINs $20,000 currently under consideration Clean Lakes Alliance in kind communication support confirmed interest in participating Wisconsin DNR $25,000 Interested, possible funding under Lake Planning Grants or nonpoint source grant programs Sand County Foundation not determined Will consider additional funding to the substantial commitment that the Foundation has already made to USGS monitoring for the 6 Mile Creek watershed US EPA not determined Will review, but most 319 program EPA funding goes to DNR administered grants Montgomery Associates $5000 Approximate amount of contribution based on discount for project labor USGS not determined Potential for cost share funding of equipment and monitoring support Madison Met $5000 Approximate value of in house water sample analysis at Madison Met laboratory Total of potential funding $75,000 Expected to increase as partners complete their review Total project costs $165,000 High side of $145,000 $165,000 estimate Current funding gap $90,000

7 Dave Tay lor Pa ge 7 Jul y 10, 2012

Healthy Farms Healthy Lakes Task Force Recommendations. Approved on August 1, 2018

Healthy Farms Healthy Lakes Task Force Approved on August 1, 2018 Introduction The Dane County Board of Supervisors created the Dane County Healthy Farms, Healthy Lakes Task Force in 2017 with a charge