Analysis and presentation of magnetometer and side-scan sonar data upon completion of a survey to locate submerged cultural resources, in addition to requirements under §26.24 of this title.

1. (1) If the survey is of sufficient duration, the magnetometer data will be corrected for diurnal variation using either separate data collected concurrently specifically for the purpose of diurnal corrections or through the use of an appropriate algorithm or mathematical formula.
2. (2) Magnetometer data will be presented on maps in a contour format. Magnetic anomalies recommended for avoidance or investigation shall be illustrated at a scale and showing isolines at appropriate levels to illustrate the complexity and intensity of individual anomalies. Illustrating anomalies at this scale may require separate illustrations from the overall survey map.
3. (3) Maps illustrating magnetic anomalies will show the actual survey lines followed by the survey vessel and thus the position of each anomaly in relation to the survey lines.
4. (4) Positive and negative nodes of magnetic anomalies shall be indicated either by different colors of isolines (e.g. red for positive node, blue for negative node) or by variation in line type (e.g. hatched or dashed) for the negative isolines.
5. (5) A map of the survey area must be included in the survey report showing both the proposed survey lines and the actual survey lines.
6. (6) A table of anomalies and sonar targets recommended for avoidance or investigation, including the positions of those anomalies or targets, shall be included in the report.

Source Note:The provisions of this §28.9 adopted to be effective August 21, 2008, 33 TexReg 6582.