Outdoor Switchgear Clearance Question

[deedo1124]

New landfill gas generating site with a unit substation (15kV-480V) installed on a containment pad. There is grating from the top inside of dike wall to equipment pad. Edge of pad extends 1'-6" from front and rear doors of 15kv gear. So as you approch the front and rear of the gear you are met with a 6" curb. Is this a violation of the NEC since there is not 3' of level working space at front and rear access doors?

Thanks for your input.

 

[7anoter4]

A sketch will be more explicative.

 

[jghrist]

What NEC rule requires the work space to be level. Work space in front of 8.6 kV (Ø-grd) equipment is 4'.