The Judy Creek Beaverhill Lake 'A' and 'B' Pools have been undergoing
pattern hydrocarbon miscible flood (HCMF) since 1985 and 1987 respecti
vely. This paper describes the evolution of the hydrocarbon injection
strategy for the Judy Creek Pools from 1985 to today. The original HCM
F design for each pattern was a water-alternating-gas (WAG) ratio of 1
.0, minimum solvent bank of 15% of the continuous hydrocarbon pore vol
ume (CHCPV), and a minimum chase gas bank of 20% of the CHCPV. Analysi
s of performance data has resulted in an evolution of HCMF design para
meters and operating strategy; injection strategy is now specific to e
ach pattern and zone. Downhole isolation equipment has been used exten
sively to improve zonal control leading to better reservoir sweep; exa
mples of this are presented. Both of these changes have significantly
improved tertiary recovery, but also have greatly increased the data m
anagement required. Imperial Oil's current method of designing, schedu
ling, and reporting hydrocarbon injection banks and WAG ratios by patt
ern and geologic zone is discussed. This includes a computer program t
hat has been developed to calculate pattern and zonal hydrocarbon bank
s and WAG ratios. Approximately 1,400 10(3)m3/d (50 mm(scf/d)) of hydr
ocarbon is injected into the Judy Creek HCMF's. Optimal use of injecta
nt is a key lever in maximizing profitability of these hydrocarbon mis
cible floods.