X0101 EFFECT 33 LIVE 2012-09-28 09:00:00

S-4

0001346980 Chaparral Energy, Inc. 333-183894 0001364760 Chaparral Real Estate, L.L.C. 333-183894-09 0001364763 Chaparral Resources, L.L.C. 333-183894-08 0001364759 Chaparral CO2, L.L.C. 333-183894-07 0001364757 Chaparral Energy, L.L.C. 333-183894-06 0001364765 CEI Acquisition, L.L.C. 333-183894-05 0001382458 CEI Pipeline, L.L.C. 333-183894-04 0001510108 Chaparral Exploration, L.L.C. 333-183894-03 0001510109 Roadrunner Drilling, L.L.C. 333-183894-02 0001408822 Green Country Supply, Inc. 333-183894-01