The 20th quarterly sampling and analysis of the LWRMN was performed during January 2004, including all of the 31 monitor wells. The USGS has completed a draft manuscript planned for submission to the Journal of the American Water Resources Association, entitled "Agricultural chemicals in ground water underlying citrus groves, central Florida: spatial and seasonal variability."

DACS is anticipating the receipt of a report on the results from a prospective ground water monitoring study being conducted in Macon, GA. In addition, Syngenta scientists are negotiating with staff to identify acceptable sites where a retrospective study would be conducted.

Arsenical Herbicides Ground Water Study

DACS is reviewing registrant responses to a request for a revised protocol for a PGW on Monosodium methanearsonate (MSMA) under reasonable worst conditions for use on turf. The study was prompted by findings of elevated arsenic levels in shallow monitor wells beneath golf courses.

Fipronil Runoff and Monitoring Studies

DACS is awaiting results of a runoff study conducted in Orange County, NC, and a freshwater surface water quality study conducted in Ocala, FL (these studies were required as a condition of registration in Florida). An estuarine surface water quality study is being conducted in Gulf Breeze, FL.

Lake Wales Ridge Lake Study (USGS et al)

Preliminary laboratory results from the fall 2003 sampling of four Ridge lakes suggest the presence of several citrus pesticides and/or associated degradates (aldicarb, bromacil, diuron, norflurazon, simazine). Additional samples from these lakes will be collected, at quarterly intervals to evaluate seasonal variability in pesticide concentrations. The lakes were selected due to evidence of strong ground water-surface water interactions and prior detections of nitrates and some pesticides in ground water in the area.

Herbicide Band Width Beneath Citrus Trees

The purpose of the project is to investigate the influence of limiting the herbicide bandwidth on discharge of two representative herbicides in surface runoff water. Three different herbicide bandwidths were evaluated: 1.2, 2.1, and 3 m widths on either side of the tree trunk. The herbicides norflurazon and simazine were applied to replicate citrus grove row-furrow-row experimental units. Surface water runoff events were initiated by applying overhead irrigation. The data showed a strong positive correlation between herbicide band width and average mass of norflurazon and simazine lost during the runoff events. Results indicate that export of herbicide residues from citrus production areas can be effectively reduced by minimizing the width of the herbicide bands underneath trees. The results of this study are being submitted for a poster presentation at the 2004 SETAC meeting.

Fipronil and Threatened and Endangered Species

Over the past year, the ESPP coordinator has worked with the FWS office in Jacksonville, Florida to address the Agency’s concern that the use of fipronil to control fire ants may adversely impact the threatened Florida scrub jay, sand skink and the blue tail mole skink. According to the current label, products registered for fire ant control containing the active ingredient fipronil (i.e., Chipco Choice, Chipco TopChoice, and Over’n Out) cannot be used "within a one-mile radius of scrub oak habitat, which is home to the Florida scrub jay, the sand skink and the blue tail mole skink." Overall, the consensus of all involved parties was to reasonably eliminate any potential for fipronil exposure to the scrub jay and the threatened skinks. However, the Department believed that the label language was not only confusing to the average user, but was also unenforceable based on complaints made by compliance investigators. Therefore, the ESPP coordinator worked directly with FWS in Jacksonville, FL to modify the language so that the label: 1) would prohibit applications in areas occupied by scrub jays, 2) was interpretable by the average user, and 3) was enforceable by our Bureau of Compliance Monitoring. Based on the above criteria, the Department, FWS, and the Registrant have agreed on the following language:

"In Florida, do not use this product within 500 feet of areas occupied by the threatened Florida scrub jay, bluetail mole skink, or sand skink. In addition, for the protection of the threatened bluetail mole skink and sand skink, apply only to turf grass and allow at least a 30-foot untreated buffer of turf grass when adjacent to scrub habitat (i.e., xeric upland) in the following counties: Highlands, Lake, Marion, Orange, Osceola, Polk, and Putnam."

With support letters from both our Department and FWS in Jacksonville, the Registrant has submitted the revised language to the Agency for approval. This example demonstrates how different agencies can work together on a complex issue and develop a solution that benefits all involved.