We investigate the electromagnetic (EM) shielding effectiveness (SE) properties of a berm which was created from soil due to construction works near a sensitive radio astronomy site. For the analysis, the berm is approximated as being located above an infinite perfectly electric conducting (PEC) plane. A two‐dimensional cross‐sectional analysis is shown to be sufficient to investigate the SE, which we compute using a computationally efficient single‐layer boundary integral equation method. To verify the method, we compare our results against those obtained by the commercially available Method of Moments (MoM) code, FEKO. Good agreement is demonstrated. It is observed that the berm provides about 25–30 dB SE at heights lower than 5 m and at distances of up to 50 m from the berm. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:17–21, 2017