EC and eLOMA Questions

Hopefully you don't find this post too convoluted, any helpful suggestions or personal experience stories would be great. Thanks

I have one Elevation Cert in progress where the BFE is above the LAG but below the bottom of vents on a poured foundation with no access for water to enter below the bottom of vents.

I know the guy is going to get nicked, but I don't know what I can report that will be of aid to his assessed rate.

1.) Do I note existing vents (as flood vents?)
My impression is these I am seeing are not intended to be flood.

This property is in a newly mapped area and was just hit up by the lenders.
The vents appear to be simply ventilation sources.

I am also finding that many of the vents I have seen have been plugged up, covered
with Plexiglass or pluggged with insulation from the inside.

Should I do all the area calculations, or do these vents not qualify?

Next,

I have a brand new BFE based on a 4' bump from the OHWM

On this particular lake there is controlled level with an outfall pipe (6 feet in diameter where the water pours in from all sides and an emergency spillway that is only .8' above the level).

The BFE seems extreme, but I am not equipped to dispute a state agency engineer.

I used the surface on the day I was there, as it appeared the
water had not been higher or lower, by the vegetation lines established.

2.) What is your technique for establishing the OHWM on a controlled lake?

Finally,

I have 2 homes which are only .2-.3' above the BFE as established with 2 hour OPUS Static Adjustment.

I have two separate Static Observation Adjustments on two points, 800' apart, with different sky views, that were occupied a week apart, that match
within .02' when compared to my turned set traverse measurements with a 3" S6

I have also found (on a good day in the wide open, my Single-Base-Line CORS RTK elevations hit within .1' of the OPUS solution, though I'm about 20 miles to the nearest station, so more often than not, the CORS RTK is pretty worthless as the vertical jumps around by many tenths when it is being challenged by bad satellite constellations or obstructions.

The closest NGS vertical control that is suitable for a GPS occupation is in a city , 8 miles away. There is no vertical control any closer to the property that 7 miles.

The historical and new FIRM lists no REF MARKS.

3.) Would you suggest I do a simultaneous occupation adjustment holding the city Mark as fixed, to check my OPUS, or
in this case would you run with the two OPUS occupations?

4.) I am running into more and more certificates now in many areas that are great distances from vertical control.
Is an OPUS solution acceptable in the eyes of FEMA, in these cases?

I don't sweat it if I have at least a couple feet of free board, but I want to be very careful with these properties that are coming up as in or squeaking just squeaking by by a couple tenths.

I was under the impression that FEMA may ask what Bench was used, and since I am doing eLOMA's on a few of these,
I want to have my numbers sufficiently backed up in case of an audit.

I am also not clear on what FEMA would demand, if or when I receive an audit on an eLOMA.