Brief Summary of Minutes of Annual Meeting

Design, Assessment, and Management of Onsite Wastewater Treatment Systems: Addressing the Challenges of Climate Change November 3, 2013 1:00 pm  6:00 pm Room 13 Tampa Marriott Waterside Hotel Tampa, FL Brief Summary of Meeting Minutes 1. The meeting began at 1:00 pm. Ten individuals, representing seven Land Grant institutions, attended the NE1045 project meeting (see participant list for details). The group welcomed the newest member, Sergio Abit from Oklahoma State University to the NE1045 participant list. Each representative institution delivered a brief update of NE1045 related activities for the reporting year. Accomplishments of these research and outreach activities are noted in the Accomplishment section of this report. 2. David Radcliffe reported on a UGA OWTS watershed research project that is providing some of the first information on the impact of OWTS in suburban streams of the Southeast. Findings are that OWTS provide a beneficial effect in maintaining stream baseflow, but above a threshold density have a detrimental effect of increasing nitrate concentrations in streams. He also reported that twenty-one new Georgia Department of Health employees attended a required Level II soils course and examination, providing them with essential training needed for their professional advancement. 3. Sara Heger reported that UMN is evaluating OWTS and wastewater from rest stops, weigh scales, and truck holding facilities across Minnesota; evaluating OWTS at six adult care facilities; performing field evaluations of a phosphorus removal system on three existing Wisconsin mound systems; and that they have disseminated their Septic System Improvement Estimator spreadsheet. UMN delivered OWTS training in five states in the region; developed and implemented new higher level design training; developed and implemented customized one-day soils workshops offered across Minnesotas soils; developed and fully implemented an onsite wastewater service provider training to meet new certification requirements; and, planned and organized the educational program for the 2012 annual conference in partnership with the Minnesota Onsite Wastewater Association. 4. John Buchanan from UTK reported on two new projects: the first project is the evaluation of the treatment potential of select pharmaceutical and person care products (P&PCP) by packed-bed recirculating media biofilters (fine gravel media). This project is being funded by a grant from the Tennessee Water Resources Research Center. Buchanan also reported on a new project to better understand the role of quaternary ammonia compounds on the inhibition of nitrification. In addition, Buchanan reported on outreach training that reached over 500 individuals in the southeast U.S. region. 5. Brad Lee from the University of Kentucky briefed the group on a collaborative project between the USDA-NRCS National Soil Survey Center, University of Kentucky, Southern Illinois University and Purdue University. The study involves measurement of in situ saturated hydraulic conductivity within six watersheds across major landscape positions at the soil surface, top of the argillic horizon, within the fragipan (if present) and in the parent material or lower argillic horizon. One of the objectives of this research is to determine the best location for placement of OWTS in these loess soils with fragipans considering projecting wetter soils conditions due to climate change. 6. Jose Amador, George Loomis and Jennifer Cooper from the URI reported on their climate change impacts to OWTS research project. Nine intact soil mesocolumns (15 x 150cm) were collected in the field in October 2012. These mesocolumns were transported to the laboratory, instrumented with three different soil treatment area (drainfield) options, and in February 2013 began receiving doses of septic tank effluent and advanced treated wastewater collected from the same residence. Water table elevation and temperature will be held constant at current climatic conditions for the first 16 months of the study, and then altered to represent climate change scenarios (raise water table by 1 foot and increase temperature by 7 degrees F). Effluent from the columns, soil gases, and grass biomass is being collected from the treatment replicates. Descriptive and predictive modeling of these systems is also occurring as well as transfer of research results to practitioners through existing education and outreach programs at the New England Onsite Wastewater Training Center at URI. In addition, 56 outreach and training classes were conducted, reaching nearly 1,800 practitioners and decision makers during the report period. 7. Sergio Abit from Oklahoma State University reported on a new Cooperative Extension program focused mainly on lectures about soil-based septic system decisions that are specific to Oklahoma and about the fates of OWTS contaminants in soils. The extension program was launched by an online lecture to county extension agents in May 2013 followed by a summer lecture tour around Oklahoma. 8. Aziz Amoozegar from North Carolina State University reported on a research project in which a data set containing more than 700 data points was used to test different pedotransfer functions for estimating soil hydraulic properties, which are critical for determining acceptance of onsite wastewater effluent. The HYDRUS model was used to simulate vertical water flow through 130 different soils. The saturated hydraulic conductivity, porosity and bulk density values of each layer for each simulation were generated from the database that was assembled previously. 9. David Lindbo from North Carolina State University and the President of the Soil Science Society of America, could not attended the NE1045 due to many SSSA meeting duties, but visited briefly to discuss with the group the progress on the national decentralized wastewater research symposium that SSSA will be sponsoring in spring of 2014 in Albuquerque, NM. This conference is a major focus of NE 1045 for 2014. David Radcliffe (UGA) reported that there are about 20 abstracts submittals thus far. SSSA has extended the deadline to December 6, 2013 and is also allowing oral presentations, so submittals are likely to increase. David Lindbo reported that other SSSA conferences have seen a large number of abstract submittals the day before a deadline, and fully expects this will be similar for this conference. George Loomis reported that we have reasonable exhibit and co-sponsor sign-up, and the group discussed how to increase the advertisement. It was suggested that SORA be contacted to help spread the word to regulatory agencies. Loomis agreed to contact Jerry Iwon, the SORA executive director. David Radcliffe will make contact with Soil Moisture Equipment Corporation at the SSSA vendor exhibit area to initiate contact with them. Brad Lee will do the same for Art Machine Shop. Follow up will occur through George Loomis or John Buchanan. 10. The meeting concluded at 5:30 pm.

Accomplishments (by project objective) Outputs Project Objective 2  Develop new OWTS design criteria for the purposes of climate change adaptation and mitigation University of Georgia findings  Synoptic samples and discharge measurements of 24 watersheds in Metropolitan Atlanta with a range of onsite wastewater treatment system (OWTS) density were taken under baseflow conditions in November 2011, March 2012, July 2012, and November 2012. Mean baseflow measurements in November 2011, March 2012, and November 2012 were not statistically different between watersheds and showed no relationship with OWTS density within the watershed, but July 2012 measurements were significantly higher in the high density septic systems (HDS) watersheds and increased linearly with increasing OWTS density. Electrical conductivity (EC) and chloride (Cl- ) concentrations increased linearly with increasing OWTS density within the watershed, and NO3- concentrations showed a linear increase with OWTS density above a threshold of about 100 OWTSs per sq.km. Results suggest an increase in baseflow due to the presence of OWTS effluent which may off-set the effects of impervious surfaces and maintain baseflow during drought conditions. Results also indicate a positive correlation between NO3- concentration and OWTS density within the watershed above a density of about 100 OWTSs per sq.km. This study showed that OWTSs have potential positive and negative impacts on the water quality and quantity of urbanizing watersheds of this region. University of Minnesota findings  UMN is conducted research evaluating 55 onsite systems and the wastewater from rest stops, weigh scales and truck holding facilities across Minnesota. The findings of this research will assist similar facilities across Minnesota designing and managing systems in the future. The UMN is also doing an evaluation of 6 adult care facilities. These facilities have a challenging waste stream due to high: flows, cleaning compounds and medicines. The Septic System Improvement Estimator project has been disseminated. The spreadsheet and users guide have been presented to professionals across MN and the U.S. This tool will assist in quantifying the positive environmental impact of improving septic systems. A similar tool is currently being developed for milk house wastewater treatment systems. In addition, UMN is performing field evaluation of a phosphorus removal system on 3 existing mound systems in Minnesota to quantify the potential benefit for phosphorus removal. University of Tennessee at Knoxville findings  UTK reported on a new project designed to evaluate of the treatment potential of trace organic contaminants by packed-bed recirculating media biofilters. This project is being funded by a grant from the Tennessee Water Resources Research Center. This project focus is on the degradation of select pharmaceutical and person care products (P&PCP) in a fine-gravel media. This treatment method utilizes the media as attachment sites for microorganisms. As wastewater trickles through the media, it becomes aerated (non-saturated flow) and compounds can diffuse in and out of the biofilm. It is thought that the combination of aerobic/anaerobic zones with endogenous respiration (plenty of oxygen, limited organic carbon) will enhance the degradation of trace organic contaminants. The evaluated compounds are two antimicrobials  sulfamethoxazole and triclosan; three non-steroidal anti-inflammatory drugs  ibuprofen, naproxen, and diclofenac; an endocrine disrupter  17±-ethinylestradiol (EE2); and, a plasticizer  bisphenol-A. UTK also reported on a new project to better understand the role of quaternary ammonia compounds on the inhibition of nitrification. Greater emphasis is being placed on denitrification as a means to prevent eutrophic conditions in surface water. However, nitrification must take place in order for denitrification to occur. It is well known that quaternary ammonia compounds (as found in sanitizers) can disrupt the biodegradation of wastewater; however, less is known about the impact of lessor quaternary ammonia concentrations as found in shampoo, detergents, and other personal care products. North Carolina State University findings  A data set containing more than 700 data points was used to test different pedotransfer functions for estimating soil hydraulic properties. The HYDRUS model was used to simulate vertical water flow through 130 different soils composed of a 10-cm thick top and 40-cm thick bottom layers. The saturated hydraulic conductivity, porosity and bulk density values of each layer for each simulation were generated from the database that was assembled previously. The simulations were performed for a 54.8 mm/hour (2 in/hour) rain representing a 5-year storm. For simulations, the soil volume in the model was saturated and then allowed to drain for 15 days before applying the storm. At the termination of simulation, the rainfall amount was partitioned into the amount infiltrating the soil and runoff. A best case, worst case and average condition were simulated to develop an infiltration index (= cumulative infiltration divided by rainfall amount) for each surface and subsurface layer pair. The infiltration index generated by these simulations can be integrated into an appropriate GIS mapping software for developing maps of infiltration for different settings within a county. In addition to theoretical simulations, an experimental study was initiated to assess infiltration and runoff in field soils. A 25.4-cm inside diameter and 50-cm long column, equipped with a 27.5-cm diameter porous plate was constructed from polyvinyl chloride (PVC) pipe. The column was tested using bulk soil materials collected from the top and subsurface layers of a soil located at a field site. After packing the column in two layers, the column was saturated and then drained before applying 5 cm of water while applying approximately100 cm of tension to the bottom of the porous plate (to simulate a water table at 130 cm depth). The column will be used to validate the findings of the HYDRUS model. University of Rhode Island findings  Replicate (n=3) intact 15 cm diameter X 150 cm long soil mesocosms were collected in the field to evaluate the effectiveness of drainfields with: a conventional septic tank effluent gravity wastewater delivery (pipe-and-stone, P&S); compared to two advanced types of drainfields receiving single pass sand filter effluent - a pressurized shallow narrow drainfield (PSND) and Geomat" (GEO), a variation of a PSND drainfield. Domestic wastewater was added to the top of the nine mesocosms and effluent collected at the bottom of the mesocosms on a weekly basis and analyzed. Water quality renovation functions were determined under current water table and temperature conditions, in anticipation of an experiment to measure OWTS response to a climate change scenario of a 30-cm increase in water table elevation and a 4æC temperature increase. Results under steady state conditions indicate complete removal of fecal coliform bacteria, phosphorus and BOD by all three drainfield systems. Average dissolved oxygen (DO) readings were 2.9mg/L for conventional drainfield effluent and 4.6mg/L for both advanced effluents, showing the expected oxygen uptake with shallow placement of the drainfield infiltrative zone. Effluent pH values maintained a steady state between 3.2  3.7 units for all drainfield technologies. By contrast, removal of total nitrogen inputs was 13.7 (+/- 2.0)% from the P&S system, and only 6.1 (+/- 1.3)% for PSND and 7.6 (+/- 2.4)% for GEO drainfields. The current hypothesis is that low oxygen nitrification is responsible for nitrogen removal as N2O in the PSND and GEO technologies, while denitrification is occurring in the P&S technology with nitrogen loss as N2O and N2 gas. None of the technologies are saturated to the 60% water filled pore space thought to be required for denitrification, however, temporary saturation may occur at the infiltrative area at the time of dosing. This saturation would be more pronounced in the P&S technology due to its twice daily dosing regimen compared to the 48 small daily doses to the PSND and GEO drainfields (following typical design regulations in Rhode Island). Additionally, wastewater may need less than 60% water filled pore space to denitrify, as this value was determined from clean water. This hypothesis will be tested in the coming months. N2O production at the infiltrative surfaces were 180 (+/-70)uL/L and 140 (+/-50)uL/L respectively for PSND and GEO technologies, and 12 (+/-2)uL/L for the P&S technology. N2 gas was not measured at this time, however, the N2O values add further support for the proposed mechanisms, with more N2O production expected from low oxygen nitrification and more N2 production (less N2O) expected from denitrification. A 15N tracer experiment along with N2 analysis will be conducted to elucidate the mechanisms controlling N removal in each technology in the coming months. The conventional OWTS drainfield is outperforming the advanced drainfields with respect to nitrogen removal, but is renovating wastewater equivalently for all other contaminants of concern. The results of this study are expected to facilitate development of future OWTS regulations and planning guidelines, particularly in coastal zones and in the face of a changing climate. A modeling component of this URI climate change project was undertaken by researchers Tom Boving and Ivan Morales with the main objective to numerically simulate the responses of the three different drainfield system options. The purpose of the modeling is to examine the potential mechanisms behind these effects, focusing on physicochemical and biogeochemical processes. The HYDRUS 2D/3D software was used to model pathogen and nutrient transport under different OWTS operating conditions, groundwater table separation distances, and soil temperatures. Moisture sensors were installed to enable monitoring the water content of each column at different depths measured from the infiltrative surface of the drainfield option. Several tracer tests were completed to determine the contaminant transport parameters such as: dispersivity, velocity, and hydraulic retention times. Tracer tests were accomplished prior to biomat formation to elucidate the changes on treatment efficiency. All three mesocosm domains have been conceptualized in HYDRUS 2D/3D to establish initial hydraulic boundary conditions. Internal observation ports were used to compare observed and optimized data. Soil moisture data was used to calibrate the model through the softwares inverse solution function, which allows researchers to obtain soil hydraulic properties from observed data. As a result, the conceptualized model exhibited a very good fit between observed and computed data (R2 = 0.99). Also, water content versus time graphs were plotted to illustrate the graphical fit, indicating that the water content values oscillate which is consistent with wastewater dosing applications to the mesocosms. The difference between observed soil hydraulic properties and those calculated by the model is very small, demonstrating that HYDRUS 2D/3D is a useful modeling tool to predict water and solute transport of our experimental domains under saturated and unsaturated conditions. Michigan State University findings  Phosphorus Removal and Recovery from OWTS. The removal and recovery of phosphorous using an engineered reactive iron media coated with nano iron is being investigated. MetaMateria, LLC, developed the media that was tested, however, other organizations have also manufactured similar materials. The media's surface precipitates phosphorus from onsite generated wastewater in a static column. Performance was evaluated using actual wastewater during a completed long-term laboratory test (approximately 600 days) and another test that has now been ongoing for over 400 days. These tests allow for the determination of the removal mechanism and the development of design criteria. Data showed empty bed contact time (EBCT) is the most important controlling factor and a minimum of 1 hour is necessary to maintain effluent phosphorus below 1 to 2 mg/L over a significant period of time. The removal mechanism is surface complexation (adsorption), governed by equilibrium. Hydraulic loading was not found to be a significant factor. In comparing monolith and granule media forms, granular shows better performance. Media exhausted during these tests will be regenerated and performance evaluated in column studies using actual wastewater. MetaMateria has effectively regenerated the media for up to 6 cycles using synthetic wastewater and in a batch treatment system. The ultimate outcome includes change in action and condition. Removal of phosphorous from onsite generated wastewater helps prevent eutrophication of surface water and growth of toxic algae that may be increasing in severity due to global climate change. Preliminary results indicate the phosphorus can be efficiently and effectively recovered as calcium phosphate and used for fertilizer at a fraction of the cost as producing a fertilizer using phosphate rock. Recovering phosphorus and producing a slow release fertilizer for crop production, as compared to mining virgin material, can reduce greenhouse gas emissions. Further, there are few sources of phosphorus in the world so local production by recovery from wastewater reduces GHG emissions associated with mining and transport. This research resulted in a Phase 2 NSF grant awarded to MetaMateria Partners, LLC, in partnership with MSU, and is an excellent example of private industry/University cooperation. Land treatment of food processing wastewater can irrigate a crop, provide nutrients, recharge aquifers, reduce energy use, uptake carbon, and save resources. When excessive carbon is land applied, the soil environment becomes anaerobic and metals naturally in soil serve as electron acceptors and become mobile when reduced. Included are manganese, iron, and, ultimately, arsenic. For this objective, major MSU activities included field studies at a MSU test site that included direct soil oxygen and moisture monitoring using remote monitoring techniques and periodic site visits to make visual observations and characterize soil. This field activity complimented previously completed column experiments. Results show that careful control of hydraulic and organic loading values helps prevent metal mobilization. However, with higher levels of oxygen in the soil, an unintended consequence is nitrate release because denitrification does not occur under aerobic conditions. Studies using wastewater pretreatment and cropping strategies are being investigated to reduce nitrate release. The outcome is a change in action and condition in that careful operations and design allow food processors to continue using this technology. Additionally, using onsite application of wastewater, as compared to treatment in a traditional activated sludge process, has a compounding reducing impact on greenhouse gas emissions. Reductions are achieved by not using energy for wastewater aeration, carbon dioxide uptake by the plant grown using the wastewater, and reduced production of industrial nutrients by using the wastewater as irrigation water for a crop commodity. Activities Project Objective 4  OWTS Training and Outreach Education On November 5 - 9, 2012 University of Georgia staff held a Level II soils workshop for 21 new Georgia Department of Health employees, including a test at the end. Approximately 180 professionals and decision makers attended five presentations that summarized the findings of the UGA watershed scale OWTS impacts study at conferences in Portland, OR and Cincinnati, OH. University of Minnesota delivered training in SD, IA, WI, IL, at the request of states, counties and professional organizations. UMN developed and implemented new higher level OWTS design training focused on advanced technology, collection and cluster systems with emphasis on aquifer assessment, nitrogen reduction, and groundwater mounding evaluations for new certifications in Minnesota; developed and implemented customized one-day soils workshops offered across Minnesotas soils regions to meet continuing education requirements of designers and inspectors; and, developed and fully implemented an onsite wastewater service provider training to meet new certification requirements. UMN staff planned and organized the educational program for 2012 annual conference in partnership with the Minnesota Onsite Wastewater Association; worked with the MN Lake Association to upgrade 15 septic systems with worked completed in 2013; and, commenced work on a NIFA-funded project to develop a customized community septic system owners guide. This tool will assist property owners in understanding how their system works and what is needed for operation. NE1045 members from University of Tennessee at Knoxville and North Carolina State University partnered together to conduct an Installation of Onsite Wastewater Treatment Systems Train-the-Trainer workshop in Murfreesboro, Tennessee on March 13-14, 2013. There were 14 attendees including NE1045 members from University of Kentucky and Oklahoma State University. During the 2013 reporting period, John Buchanan at UTK was an invited speaker at several regional and national onsite wastewater events including educational seminars at the Pumper/Cleaner Expo, the National Onsite Wastewater Recycling Association, the North Carolina Septic Tank Association, and the Tennessee Onsite Wastewater Association. In all, these outreach efforts reached approximately 500 homeowners, maintenance providers, designers, and system installers. Oklahoma State University  OSU reported on a new Cooperative Extension program focused on soil-based OWTS decisions that are specific to Oklahoma and about the fates of OWTS contaminants in soils. The extension program was launched by an online lecture to county extension agents in May 2013 followed by a summer lecture tour around Oklahoma that were attended by 84 participants comprised of personnel from the Oklahoma Department of Environmental Quality (DEQ), Certified OWTS Installers, Health Department Sanitarians, sanitarians from the Indian Health Services, representatives from various Native-American Nations and County Extension Educators. In addition, short lectures about various topics related to OWTS ranging from soil-based OWTS decisions, aerobic treatment units and simple maintenance of OWTS were also delivered to members of the Oklahoma Certified Installers Association, the Oklahoma Society of Environmental Health Professionals and homeowners. Michigan State University  A new MSU continuing education program for onsite wastewater treatment systems (engineers) and evaluators (public health officials) is being developed based on the completed USDA Challenge Grant ECOSEAM project. Included are distant learning modules and in person workshops. University of Rhode Island  During the reporting period, the URI project team delivered 56 workshops/ classes in 5 states in the region, reaching a total of nearly 1,800 practitioners, decision makers and students. These classes provided continuing education credits needed by over 1,600 licensed professionals to renew their professional licenses. These classes included in-door and out-door hands-on venues and ranged from half-day to two-day venues with qualifying exams. During the report period, URI scientists have provided direct OWTS technical assistance to: Old Saybrook, CT; Oyster Bay / Cold Spring Harbor, Long Island, NY; Peconic Estuary, Long Island, NY; and, Great Bay Watershed Alliance Communities, NH. Coordinating with Vermont DEC OWTS regulators and the Vermont Technical College, URI offered two classes to train VT practitioners on OWTS pumps and controls and high strength wastewater treatment. URI conducted three required classes for Rhode Island and Massachusetts wastewater practitioners to enable them to receive regulatory jurisdiction approval to design and install bottomless sand filters. URI researchers made invited presentations at five conferences about climate change and OWTS reaching 140 board of health officials, regulatory decision makers and coastal resource managers. University of Arizona  conducted 5 classes with 155 participants total for the report period (topics included Septic Inspection, Soil and Site Evaluation, OWTS Technologies). Kitt Farrell-Poe is a member of Arizona Department of Environmental Quality (ADEQ) Onsite Wastewater Advisory Committee (OWAC). OWAC meets monthly; its purpose is to assist and counsel ADEQ in selecting and altering courses of action for guiding the Arizona onsite industry in a direction that is most beneficial for the citizens and environment of Arizona and facilitate the implementation of actions taken. She is an at-large member of the Arizona County Departments of Environmental Health Services Association (ACDEHSA) subcommittee Onsite Technical Advisory Group; continues to work on States Report of Inspection form to incorporate review comments; continues to work with state association of county health departments to incorporate Consortium of Institutes for Decentralized Wastewater Treatment (CIDWT) Glossary of Terms into rule change recommendations; working on planning committee for 2014 (biennial) Southwest Onsite Wastewater Management conference held in Laughlin, AZ, in late January. Ms Farrell-Poe is collaborating with the University of Minnesota on the Community Septic Systems Owner's Guide, serving as a member of the Project Development Team to create the contents of the various modules and more specifically to develop, review, revise, and refine materials gained from the other national development programs and to test the beta version of the CSOG with communities in Arizona.

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