Consulting engineer report (stamped) for residential remodel in flood plain- West Johnson Creek 97005

Residential addition in floodplain. I need engineering report certifying that project will not increase BFE or increase flood flows. Also addition of incremental 1' contours to site plan (from existing survey, no additional survey required) and confirmation of balanced cut and fill (again, obvious and will be conditional anyway). Project doesn't encroach into floodplain closer than existing development. County flood plain administrator confirms (and will discuss with engineer) that project obviously doesn't impact BFE or flood flow rate but because Type II flood plain alteration permit is required, consulting engineer certification is required. Development permit application is complete except for report from consulting engineer so, according to the county (Sean Harrasser) all I need is stamped letter