32Determining potential plot locations

32 Determining potential plot locations

(1) Where this determination requires a set of potential plot locations to be established for a particular area of land, a grid overlay must be established on a map of the area using:

(a) the method set out in subsection (2); or

(b) a commercial software package that generates a suitable grid of square cells by a process that does not allow the user to set the angle or anchor point.

(2) For subsection (1), the method is to use a geographic information system to establish the grid overlay as follows:

(a) the grid must be composed of square cells;

(b) the grid must be initially located with grid lines running:

(i) north to south (vertical grid lines); and
(ii) east to west;

(c) the grid must be then be realigned as follows:

(i) use a random process to generate a random angle value between 0 and 89 degrees; and
(ii) rotate the grid orientation clockwise around the point of grid intersection so that the vertical grid lines move by that angle;

(d) one grid intersection must then be aligned over:

(i) one of the fixed anchor points described in subsection (5); or
(ii) an anchor point obtained by randomly selecting an easting and a northing coordinate that are:

(A) within the ranges of easting and northing coordinates for the stratum; and

(B) from the current version of the Map Grid of Australia 1994 (MGA94).

Note: The Map Grid of Australia 1994 (MGA94) is available at: http://www.ga.gov.au/earth-monitoring/geodesy/geodetic-datums/GDA.html

(3) Each grid intersection that lies within the area after completing this process is a potential plot location.

(4) The size of the cells of the grid must be selected to ensure that the number of potential plot locations for the area determined in accordance with this section is at least the number desired.

Note: If an appropriate cell size is chosen, the same grid may be used for an area that is made up of all strata. However, see provisions when the existing set of potential plot locations is insufficient.

(5) For this section, the fixed anchor points are:

(a) spatially projected using the ‘Lamberts’ conformal conic projection referencing the GDA94 datum; and

(b) defined as having either of the following coordinates:

(i) X = 1,277,100 metres, Y \= ‑3,762,300 metres;
(ii) X = ‑1,666,331 metres, Y = ‑3,482,739 metres.