A sample sealing technique was developed and tested for a possible Mars Sample Return mission application. The effect on the scientific viability of biological samples from storage of samples in a sample container for a long period of time on the Martian surface was also investigated. Sealing techniques were investigated and a soldering concept was developed and tested to provide a hermetic seal between a sample tube and cap. A sample caching subsystem design concept was updated to allow for sealing of sample tubes. A gas-tight vessel was constructed that could be used to simulate environmental conditions that would be experienced by a sample of regolith on Mars and to test the affects of thermal cycling of the vessel on psychrophilic microorganisms embedded in a regolith simulant to assess the degree of deterioration of the microorganisms.