  Bioenergy with Carbon Capture and Sequestration (BECCS) is critical for
stringent climate change mitigation, but is commercially and technologically
immature and resource-intensive. In California, state and federal fuel and
climate policies can drive first-markets for BECCS. We develop a spatially
explicit optimization model to assess niche markets for renewable natural gas
(RNG) production with carbon capture and sequestration (CCS) from waste biomass
in California. Existing biomass residues produce biogas and RNG and enable
low-cost CCS through the upgrading process and CO$_2$ truck transport. Under
current state and federal policy incentives, we could capture and sequester 2.9
million MT CO$_2$/year (0.7% of California's 2018 CO$_2$ emissions) and produce
93 PJ RNG/year (4% of California's 2018 natural gas demand) with a profit
maximizing objective. Existing federal and state policies produce profits of
\$11/GJ. Distributed RNG production with CCS potentially catalyzes markets and
technologies for CO$_2$ capture, transport, and storage in California.
