Search for parcels near substations or lines but within the bounds of an individual county.
This process will have you create an initial buffer around your desired grid infrastructure and then create an intersection of that search area with the county boundary to create the final desired search area.
Create buffer area around grid infrastructure using the combo buffer tool
On the created project, create a buffer around the grid infrastructure using the combo buffer tool (Parcels tab > See Actions > Project Tasks > Create combo buffer)
You will then see the buffer on the map around the grid infrastructure. In this example, we created a buffer around all the lines on this project:
Combo buffer should appear around grid infrastructure as an orange polygon
Save county boundary to project map
Turn on County Boundaries layer (map toolbar > layers > County Boundaries)
Click on the target county on the map layer
In the pop-up window, click the 'Copy feature' button to copy the county's boundary to the project map as a drawing
Turn off county layer (target county should now be saved to the map as a black polygon)
County boundary appears as a black polygon on the map
Create intersection of grid combo buffer and county polygon
To create the final desired search area, select the two polygons and create an intersection polygon which represents the search distance around the grid infrastructure but within the bounds of the county.
Select the combo buffer polygon and the county buffer polygon by holding down the CTRL key (Mac users: COMMAND key) while you click each polygon on the map with your cursor
In top-right corner of map, you should see the selected polygons
CTRL + click combo buffer polygon and county polygon to select them in the map sidebar
Click the Design button
Click 'Create intersection buffer'
This will create a new polygon which is the final search area, however, it won't be clearly visible as the original polygons will cover it on the map.
Remove old polygons that are no longer needed:
Click the black county boundary that you originally copied and delete it from the project
Click the orange combo buffer polygon and delete it (pop up > red trashcan)
This should leave you with the intersection polygon remaining which is your final search area
Run the parcel search on the new search area polygon