Boring locations shall be indicated on the plat, with a soil log supplied. A minimum number of borings (showing ground elevation, depth to ground water, and date of boring), one per five acres, with a minimum number of two borings per plat, shall be provided. If special natural conditions dictate, the Planning Board Engineer may require that additional borings are needed based on the natural conditions or the use of the site. Where the project will be served by sewers, soil borings are necessary in the area of proposed stormwater drainage facilities.