We report on neutron scattering measurements on the vortex lattice of the noncentrosymmetric superconductor BiPd. We observe the existence of the intermediate mixed state, a region where Meissner and vortex lattice phases coexist, which is a feature of low κ type-II superconductors. Following this, we obtain an estimate of the value of κ using the extended London model. Finally, we find that the temperature dependence of the vortex lattice form factor fits well to a model designed to describe singlet-triplet mixing in noncentrosymmetric superconductors, which may shed light on the question of the gap structure in BiPd.