Any public agency or person requiring land in an agricultural preserve for a use which has been determined by a city or county to be a “compatible use” pursuant to subdivision (e) of Section 51201 in that agricultural preserve shall not be excused from the provisions of subdivision (b) of Section 51291 if the agricultural preserve was established before the location of the improvement of a public utility was submitted to the city, county, or Public Utilities Commission for agreement or approval and that compatible use shall not come within the provisions of Section 51293 unless the location of the improvement is approved or agreed to pursuant to subdivision (a) of Section 51293 or the compatible use is listed in Section 51293.