We explore the feasibility of low probability of intercept for sonar signals. Using a noise-like active sonar signal, the transmitter (platform) employs a matched filter for echo detection while the target is assumed to use an energy detector. Decision statistic distributions are developed at both the platform and target. These distributions allow efficient Monte Carlo simulation of detection performance and comparison with a previous work's assumption of Gaussian decision statistics. We then explore the detection advantage the platform can achieve by evasive on-off keying and by optimization of its transmitted power. We identify a favorable (evasive) operating region for the platform in the (low power, small range) region of the (range, power) plane. This suggests that the platform should start detection (and range-finding) using a low-power probing signal, increasing power until a reliable detection rate is first achieved while ensuring the target's detection rate does not exceed a specified level.