The North Wig Grid is located twenty miles north west of Dog Area. The grid proper is 2700 feet square and consists of twenty-eight sampling rows spaced 100 feet apart.

The center of the grid, which is 500 feet square, has sampling stations located on 25 foot centers. For the remainder of the grid, these stations decrease to 50 foot centers for a 900-foot square, and every 100 feet for the remainder of the grid.

Each of the twenty-eight sampling rows has a piped vacuum system and is controlled independently. A 132 cfm vacuum pump provides the required vacuum for each row and power is supplied to the grid by three generators.

The grid is wired with a 110 volt single phase control system to allow for operation of sequential sampling systems.

The North Wig grid is used to function both chemical and biological munitions and disseminating devices but has no provisions for conducting downwind sampling.

The grid array is given on the following page.