This document discusses high pressure and high temperature steam leakage from the high pressure to intermediate pressure turbine due to seal damage or misalignment. Some effects of this leakage include increased heat rate and decreased efficiencies. The leakage can also cause load curtailment, thrust balance issues, and difficulty controlling reheat temperatures. Methods for detecting and estimating the leakage include temperature variance tests and blowdown tests. The document provides details on performing each type of test and calculating the leakage rate.