Prior studies, including the previous pesticide monitoring program, have indicated that agricultural activities often produce elevated nitrate nitrogen concentrations in groundwater. The average nitrate concentration found in the 7 golf course irrigation wells sampled in 2001 was 4.7 mg/L, with a median concentration of 3.5 mg/L. No wells exceeded the nitrate MCL of 10.0 mg/L. The irrigation well at Engineers Country Club had the highest nitrate concentration of 8.0 mg/L (This well also exhibited a metalaxyl concentration of 0.15 ug/L).
Nitrite was not detected in any of the samples and there was 1 ammonia detection of 0.26 mg/L at the Garden City Country Club irrigation well. Table 4 summarizes the Ammonia, Nitrite and Nitrate concentrations for each golf course well sampled in 2001.
|GOLF COURSE||WELL #||AMMONIA||NITRITE||NITRATE|
|Garden City C.C.||N-7799||0.26||<0.02||3.2|
|Cherry Valley C.C.||N-6905||<0.02||<0.02||5.3|
|Garden City G.C.||N-6502||<0.02||<0.02||3.5|
|all results as mg/l|
There were no perchlorate detections in the 7 shallow golf course irrigation wells sampled in Nassau County.