f gray or silver g orange h yellow or gold i or black all as further noted in fig1 and fig5 a through 5i the cover 20 is preferably made with a ultraviolet resistant and rated plastic with high strength and of weather resistant material as noted in fig4 covers are ideally manufactured with a sufficient downward slope angle alpha from the horizontal line 70 that allows about one inch per foot slope away from the structure 12 to detour moisture away from the foundation and out of crawl spaces and basements covers also should be manufactured with strength to support human weight we prefer a structure having a top thickness of at least u00be inches and with ribs of about u00bd inch in transverse cross section the rib structure noted in fig2 should be evaluated and confirmed based on the material of construction actually selected ideally a criss cross block shaped strengthening rib structure 71 is advantageously employed extending below the bottom surface 72 of the top protective portion 22 as shown in fig2 transversely running 74 and longitudinally 76 running rib portions are provided also a non skid texture as noted in fig1 is advantageous it is to be appreciated that the various aspects and embodiments of the cover for crawl space access and for basement window well structure as described herein are an important improvement in the state of the art of structures and materials to cover crawl space access and to cover basement window wells a plastic cover as described herein is virtually non destructible by insects vermin and the elements and is easily made with adequate strength to support human weight importantly such a cover well.