In his book A Colony Detailed Ian Berryman lists 19 deaths in Fremantle in 1830 but the cemetery in Alma Street wasn't opened until 1831. The 1833 plan indicates that lots 433 and 448, shown in maroon, in Market Street were 'reserved to the Crown, being the site of the original Burial Ground'. Errington: 20. [Footnote. Ian Berryman, A colony detailed: the first census of Western Australia 1832, Creative Research 1979, pp 159-62.]
[Errington has added not only the black line but also the 'legend'. It may have been copied and pasted from another part of the same map - of which what is shown above is only an excerpt. The resolution in the journal is not high enough to see.]
Errington, Steve 2017, 'Fremantle 1829-1832: an illustrated history', Fremantle Studies, 9: 15-29. The reference Errington gives for the map is: SROWA, cons 3868/109.