Monitoring Results Golf Course Irrigation Wells

Pesticides and Metabolites

Seven shallow golf course irrigation wells were sampled in 2001 (Figure 2). Each of these wells are screened in the upper glacial aquifer and vary in depth from 61 to 90 feet.

Pesticide or pesticide degradation products were present in 5 of the 7 wells tested. The following five pesticide-related compounds were found: Chlorothalonil, Dieldrin, Metalaxyl, TCPA and Triadimefon. The fungicide Metalaxyl was the most commonly detected compound, being found in 3 of the golf course irrigation wells tested. No detected compound exceeded its drinking water MCL. The levels of the pesticides detected are summarized below in Table 3.

Table 3 - Pesticide Detections in Golf Course Irrigation Wells

GOLF COURSE PESTICIDE LEVEL
(ug/L)
MCL
(ug/L)
Garden City C.C. Dieldrin 0.16 5.0
Garden City G.C. Chlorothalonil 0.23 50.0
  Triadimefon 1.83 50.0
Engineers C.C. Metalaxyl 0.15 50.0
  TCPA 22.00 50.0
Rockville Links-1 Metalaxyl 0.21 50.0
Rockville Links-2 Metalaxyl 0.18 50.0

Appendix E describes the sources of the pesticides found in the public supply and irrigation wells during the 2001 round of sampling.