AbstractThe town of Yarmouth, Massachusetts, proposed to locate a new municipal golf course within a delineated area of recharge to public water‐supply wells. Two concerns of town officials were (1) hydrologic impacts upon downgradient wells; and (2) water‐quality impacts from fertilizers and pesticides. In response to these concerns, a thorough hydrogeologic investigation was made, fertilizer and pesticide management programs were recommended, and a ground water monitoring program was developed.The golf course parcel was determined to be underlain by a sand and gravel aquifer composed primarily of glacial outwash. Water‐table maps confirmed that ground water flow was in the direction of several public water‐supply wells. A three‐dimensional finite‐difference flow model was used to determine the optimum location and pumping rates for irrigation wells. Potential nitrate‐nitrogen concentrations in the ground water were predicted to range from 5.0 to 7.9 milligrams per liter so slow‐release fertilizers were recommended.With the assistance of the EPA Office of Pesticide Programs, the list of proposed pesticides was reviewed and sorted into three categories based on the known leachability, mobility, and toxicity characteristics of each compound. Specific recommendations were made as to pesticide selection and application rate using that classification.A monitoring program was developed to provide an on‐going assessment of any effects on water quality related to the application of fertilizer or pesticide. The elements of the monitoring program include (1) specifications for monitoring wells and lysimeters, (2) a schedule for sampling and analysis, (3) specific concentrations of nitrates or pesticide compounds that require resampling and analysis, restriction of usage, or remedial action, and (4) regular reports to the Yarmouth Water Quality Advisory Committee and to the Yarmouth Water Department. In an effort to ensure the implementation of this program, a table of responsibilities was prepared, and a Memorandum of Understanding adopting the program was signed by the town agencies interested in water‐supply protection and the golf course operation.The monitoring facilities were installed with minimal problems as part of the golf course construction tasks. However, implementation of the sampling and analysis part of the program was accomplished only after some difficulty and delay. The assistance of the State Pesticide Bureau, the University of Massachusetts Department of Entymology, and the Massachusetts Pesticide Laboratory was enlisted when budgetary problems threatened to prevent implementation. It is apparent from Yarmouth's experience that the mere preparation of a plan is not sufficient by itself. Consultants who prepare the plan should make every possible effort to include implementation in thei