Fate and transport of pathogens and nutrients from land-applied animal manures

Five monitoring sites at the LWRFL (fig. 1 and table 3) have been established for use in collecting water-quality samples and continuous discharge data. Monitoring sites ST1A, SR1, SR2, and ST1D were established to monitor stormwater runoff at the swine facility. Monitoring site BR1 was established in an agricultural field with no animal waste inputs to generate background data for use in examining relative differences in bacteria and nutrient loadings associated with sites SR1 and SR2 that receive overland runoff from the swine waste application fields. A rain gage was installed at site ST1A for recording continuous data on precipitation at the LWRFL.

Downstream monitoring station ST1D.	Overland runoff monitoring station SR1.

At each monitoring site established as part of task 1, USGS will continuously measure water stage and perform discharge measurements to develop continuous records of discharge at each site. Pre-fabricated flumes have been installed at overland runoff sites BR1, SR1, and SR2 (fig. 1 and table 3). Discharge rating curves for the flumes will be used in combination with continuous stage measurements in each flume to determine continuous discharge records for each site.

Samples of fecal waste-material will be collected from the animal waste-storage lagoons at the swine operation for laboratory analyses (fig. 1). Samples of swine waste applied by spraying of lagoon effluent also will be collected in the waste application fields. The samples will be analyzed primarily for fecal bacterial indicators, pathogens, molecular biomarkers, and antimicrobial resistance (table 1). Select samples will be analyzed for nutrients (table 2).

Samples of surface soil material will be collected from the swine waste application fields for laboratory analysis of pathogens, fecal indicator bacteria, and antibiotic resistance bacteria, and host specific molecular biomarkers (fig. 1, table 1). Ideally, a soil sampling event will be conducted in coordination with the spraying of lagoon effluent in the application fields. Samples are proposed to be collected the day before spraying, the day of spraying, and then at 3, 7, 14, and 28 days following the application event.

At the five monitoring stations (fig. 1), automated samplers will be used to collect water samples during approximately 6 rainfall-runoff events during the one year monitoring period. For each event, approximately 5 samples will be collected at each site for microbiological and chemical analyses (table 1 and table 2). The water quality samples will be analyzed primarily for fecal bacterial indicators, pathogens, molecular biomarkers, antimicrobial resistance, and nutrients.

In addition to storm-event sampling, instantaneous water samples will be collected on approximately a bi-weekly basis to establish baseline water-quality information. Samples will be collected at the upstream and downstream automated monitoring stations (sites ST1A and ST1D) and at two additional baseline sites (sites ST1B and ST1C) not included in the runoff monitoring network (fig. 1 and table 3). Discharge measurements will be performed at the time of sampling. The water samples will be analyzed primarily for fecal bacterial indicators, pathogens, molecular biomarkers, antimicrobial resistance, and nutrients (table 1 and table 2).

USGS staff will work with LWRFL staff to obtain available information on past and present activities at the swine operation that may be beneficial to interpreting data results obtained during the study. To the extent possible, USGS will compile information on waste applications (manure types and amounts, timing, and field locations), inorganic fertilizer applications, crop rotations, livestock populations, and historical pharmaceutical use for the swine operation.

Upon completion of field data collection activities, the USGS will work in collaboration with EPA to jointly complete an USGS Open-File Report (available online) that compiles and summarizes results of data collection activities at the LWRFL. The study results will provide animal producers, public health officials, and water-resource managers, at local and national levels, with beneficial information in designing and implementing best management practices for reducing the load of pathogenic microorganisms, nutrients, and OWCs reaching the environment.