Under the high-level liquid waste (HLLW) partitioning strategy, Sr- and Cs containing waste package can be disposed of at intermediate-depth or near-surface through long-term decay storage with reduced thermal power and radioactivity concentration. According to China’s radwaste classification regulation, the activity concentration requirement of α-nuclides in SrCs waste packages for intermediate-depth disposal is too broad (α > 4 × 106 Bq/kg, i.e., upper limit for α in low-level waste; α + β + γ < 4 × 1011 Bq/kg, i.e., lower limit for α in HLW) to be used as a basis for calculating the residual amount of α residues in the SrCs waste. Therefore, this study proposes a recommended value of 108 Bq/kg for the upper limit of α-nuclide residue in SrCs waste for intermediate-depth disposal from the perspective of radiotoxicity attenuation of residual α-nuclides in the waste packages and safety protection for unintentional intruders after closure of intermediate-depth disposal facilities. Based on this result, the TRPO process for HLLW partitioning developed in China is fully capable of fulfilling the α decontamination requirement (α decontamination factor = 1500) for Sr- and Cs-containing waste stream.