retaining wall 12 and covered by an oval shaped storage cover 10 fig5 shows yet another alternative configuration wherein the storage cover 10 is secured to the ground rather than a retaining wall 12 the retaining wall 12 can be solid or perforated as shown in fig1 and 4 when the retaining wall 12 comprises perforations 16 this allows for air to flow through the retaining wall 12 the tarp body 18 may be made from a variety of materials however usually the tarp body 18 is made from a water proof non permeable fabric such as polyvinylchloride or polyethylene that protects the particulate material from rain moisture and weather but does not allow air to flow through the tarp body 18 it is advantageous to aerate a covered particulate pile to prevent molding moisture migration and insect or rodent infestation to aerate a particulate pile aeration fans 15 may be installed along the perimeter of the storage cover 10 as can be seen in fig1 7 to draw air out of the particulate pile the aeration fans 15 can be of any of the types and sizes known in the art and are generally selected based on customer specifications for example a grain guard u2122 galvanized vane axial or centrifugal aeration fan sold by ag growth international may be used generally aeration fans 15 are installed every 20 30 feet but may be installed closer together or farther apart in an attempt to draw air from the interior of the particulate pile rather than from just the perimeter of the pile where the fans are located aeration pipes 30 are attached to the aeration fans 15 and positioned on the ground prior to depositing the particulate material aeration pipes 30 are generally made from perforated corrugated polyethylene pipe.