The Indian Bureau of Mines (IBM) established in 1948, is a multi-disciplinary government organization under the Department of Mines. It is headquartered at Nagpur, Maharashtra. It is engaged in promotion of conservation, scientific development of mineral resources and protection of environment in mines other than coal, atomic minerals, petroleum & natural gas and minor minerals. It is primarily advisory body to help in formulation of policy and legal framework for mining sector and advising Central and State Governments on development and utilization of mineral resources.
Mission
The primary mission of Indian Bureau of Mines is to promote systematic and scientific development of mineral resources of the country (both onshore and offshore), through regulatory inspections of the mines, approval of mining plans and environment management plans to ensure minimal adverse impact on environment.
It has been proposed to use a combination of digital aerial (Drone and satellite) images to monitor mining activities in the country. In mining, drones have various applications like mine surveying, inventory management, stockpile evaluation etc.
Ministry of Mines has incorporated Rule 34A in the Mineral Conservation and Development Rules 2017 for submission of digital aerial images of mining lease areas to Indian Bureau of Mines
What is MCDR?
The MCDR have been framed under section 18 of the Mines and Minerals (Development and Regulation) Act, 1957 [MMDR Act] to provide rules regarding conservation of minerals, systematic and scientific mining, development of the mineral in the country and for the protection of environment.
The provisions of rule 34A of MCDR are as follows:
- Every lessee having
(a) an annual excavation plan of one million tonne (10 Lakh tonne) or more in a particular year, or
(b) leased area of fifty hectare or more, The above mentioned should carry out a drone survey of the leased area. They need to survey upto 100 metres outside the lease boundary in the month of April or May every year and submit the outputs or any other format as specified by IBM on or before JULY 1st every year. - Every lessee, not mentioned in the 1st rule, shall submit soft copy of high resolution Georeferenced Orthorectified Satellite images of the leased area. They need to survey upto 100 metres outside the lease boundary in the month of April to June every year and submit in GEOTIFF format along with the metadata or any other format as specified by IBM on or before JULY 1st every year. The lessee who has submitted images under the 3rd rule need not submit this result.
- Every Lessee, who needs to submit any mining plan document or modification to IBM need to carry out a drone survey. They need to survey upto 100 metres outside the lease boundary within six months before submission and shall submit the results along with the application for approval or modification of mining plan to the concerned Regional Controller of Mines and the Controller General, IBM.
- Bidders issued with a letter of intent (LOI) for grant of a mining lease shall carry out a drone survey of the mining block granted through auction. They need to survey upto 100 metres outside the lease boundary and submit the outputs along with the mining plan to the Regional Controller and the Controller General, IBM.
- The SOP for carrying out the drone survey and form of the data to be submitted shall be specified by IBM from time to time.
KML Boundary Extension
As per IBM, the drone survey should be conducted upto 100 metres outside the lease boundary. If you are confused on how to increase the lease boundary, you can extend your original KML boundary using the KML Boundary Extension free tool from this website.
Enter the website and upload your orginal KML boundary. At the top right corner input the distance in meter upto which you need to extend the boundary and click submit.
From Figure above, we can see the original KML boundary is denoted by the Yellow boundary. The green boundary is the extended boundary.
Download the official SOP for UAV Survey from here.
What is an SOP?
SOP stands for Standard Operating Procedure. A standard operating procedure is a document that contains step-by-step instructions and guidelines for employees to follow when performing a technical, repetitive process within an organization. SOPs are employed by a number of organizations to guarantee that tasks are carried out consistently, effectively, and with the least chance of error or omission.
Standard Operating Procedures for carrying out drone survey and submission of Digital Aerial Images of
Mining areas to Indian Bureau of Mines
1. Drone Agency Registration and Permissions
There is no need to register with IBM for drone survey in mines. Drone Agencies or the lessee can conduct the survey while following all the applicable rules, regulations and guidelines notified by DGCA. Check the Airspace map from the Digital Sky website. The drone airspace map is an interactive map of India that demarcates the red, yellow and green zones across the country.
Green zones are the unrestricted zones where drones can be operated without any permission.
Yellow zones are controlled zones and the drone can only be operated after a permission from DGCA.
Red zones are highly restricted zones and can be operated only after permission from the authorities.
From Figure above, In the Airport Yellow [8-12 km] zone , drones can be operated only upto 60m. In the Airport Yellow [5-8 km] zone and Airport Red zone , drones can be operated only after permission from DGCA.
From Figure above, we can see that this is the International Boundary. This is a highly restricted zone.
2. Drone Specification
Drones used for the survey should follow DGCA guidelines and should possess mandatory safety features as notified by DGCA from time to time.
3. Sensor/Camera Specification and output data resolution
The drone should have a minimum 20 megapixel or higher resolution RGB camera with the capability to capture high-quality undistorted pictures. Camera should have the resolution to capture the images less than 5 cm Ground Sample Distance or 5 cm per pixel. The resolution of Digital Elevation Model should be 15 cm/pixel.
You can study more about GSD from our previous blog.
4. Drone flying path and flying height
The path plan should be such that there is enough overlap between the photos. The front overlap should be minimum 80% and side overlap should be minimum 70%. The flight altitude should be as per DGCA prescribed limits. The camera angle should be kept at 90° vertically downwards.
You can study more about the flight altitude and overlap from our previous blog.
5. Survey Area
The survey should cover the entire mining lease area capturing all mining, allied activities and 100m beyond periphery of the mine lease boundary to monitor the environmental impact and ascertaining any excavation therein. The flight path plan and the numbers of flights taken to cover the entire area shall be provided to IBM along with the output data. For leases having common mine boundary, the survey may be limited up to the lease boundary for the sides, the lease shares common boundary with another lease.
I use the KML Boundary Extension from this website whenever I need to extend my original KML boundary.
6. Ground Control Point for Drone Surveys
Each mine must establish at least 5 GCPs per sq. km of lease area with a certified DGPS instrument before undertaking the drone survey. If area is less than 1 sq.km, 4 GCPs are only needed.
Points to Note while placing GCPs:
- GCP must be easily visible.
- It should be well distributed all over the area.
- Dimensions: Minimum 50cm by 50cm and mark X with contrast colors
- Increase the size of the GCP depending at which height you fly.
- The Root Mean Square (RMS) Error should be less than 5cm.
- At least 3 GCPs must be placed permanently at undisturbed locations and has to be covered in subsequent surveys to cross check the error.
- Boundary pillars shouldn’t be considered as permanent GCPs.
You can take a closer look and study more on GCPs by visiting this blog.
7. Drone Survey Time
It is advised to fly the drone in better conditions when the sky is clear and the sun is overhead to minimize the shadows in photographs. Do not fly the drone when it is rainy or windy.
8. Co-ordinate Reference System
The Co-ordinate Reference System of the photos captured and used in drone survey should be in (Latitude, Longitude) with WGS84 Datum and Decimal Degrees/Degree Minute Seconds as unit.
To find the coordinates of the photo used in the drone survey, right click on the image and got to Properties and then switch to the Details tab and scroll down to the GPS section.
From Figure above, these are the photos captured by the drone and here you can see that the (Latitude, Longitude) values are in Degree Minute Second (DMS).
The Orthomosaic shall be submitted in the Universal Transverse Mercator (UTM) and unit as meters.
From Figure above, this is an orthomosaic file and here it is in UTM Coordinate Reference System having EPSG Code: 32643 and the coordinate values are in meters.
The GCPs survey data and boundary pillar coordinates shall be submitted in (Latitude, Longitude) with WGS84 Datum and Degree Minute Seconds as unit.
The precision of the data submitted in (Latitude, Longitude) with WGS84 Datum should be in format as (DD MM SS.SSSSSS)
From Figure 7 above, it shows the properties of an image used in drone survey. Here the (Latitude, Longitude) values are in Degree Minute Second (DMS) and in the seconds value you need to have precision upto 6 digits.
9. Preservation of Raw and Processed Data
The raw and processed data of each survey must be kept safely with the lessee for a minimum period of five years. The data must be submitted to IBM in case required by IBM for verification at any stage. The data can be stored in cloud platforms such as Surveyaan Geoworkspace, so that there is no risk of getting the data lost or corrupted.
10. Data Output and Formats
The outputs that need to be submitted are discussed below:
Orthomosaic
Orthomosaic is a large, high-resolution map-quality image that combines many smaller images called orthophotos. Submitting the orthomosaic image of the leased boundary to IBM is mandatory. As a reminder, the orthomosaic of the leased boundary should also incorporate a 100m buffer zone. The buffer zone is included to monitor the environmental impact and ascertain any excavation therein. The data should be submitted in a GEOTIFF format.
Figure above shows the Orthomosaic map in Geotif format.
Make sure the Ground Sample Distance (GSD) is less than 5 cm per pixel or 5cm per pixel.
GSD is the distance between the centers of two successive pixels on your map, measured in inches, centimeters, or millimeters. A drone can measure with a GSD of 5 cm/px, meaning that each pixel on your digital map represents 5 centimeters of actual space in the real world.
Digital Elevation Model (3D) — DSM & DTM
The Digital Elevation Model is a 3D representation of the terrain elevations on the earth’s surface.
The Digital Terrain Model is a subset of DEM and consists of the earth’s surface and excludes buildings, trees, etc.
The Digital Surface Model is a subset of DEM and consists of the earth’s surface, including all objects like buildings, trees, etc.
While submitting to IBM, ensure the DSM and DTM are in GeoTif format.
Figure above shows the Digital Surface Model and Digital Terrain Model in GeoTif format.
The resolution of the Digital Elevation Model (DEM) should be 15 cm per pixel or better.
Ground Control Points
Ground Control Points (GCPs) are the points on the earth’s surface that help georeference raster data such as satellite, aerial, or drone imagery. The GCP data should be submitted to IBM in shapefile and Excel format.
Figure above is an Orthomosaic image in GeoTif format. The red points are the Ground Control Points overlaid on the orthomosaic file in shapefile (SHP) format.
Figure above is an Orthomosaic image in GeoTif format. The red points are the Ground Control Points overlaid on the orthomosaic file in shapefile (SHP) format.
Figure above is the GCP data in Comma Separated Value (CSV) format.
RMSE Report
RMSE is used to measure the difference between 2 values or datasets. Here, the first dataset is the error value obtained from the GCP points in the ground, and the second dataset is the error value obtained after processing in the Photogrammetry Software. With the help of any Photogrammetry Software, we can get a detailed GCP report. I have generated the report using Surveyaan Geoworkspace. The RMSE report should be submitted to IBM either in .txt or in .doc format.
From Figure above, we can view the GCP report in .doc format.
Map
The lessee should submit the map of the mining lease to IBM showing area of;
a) actual excavation (mineral and waste)
b) Mineral storage
c) Subgrade dump
d) Waste dump
e) Afforestation
f) Backfilled, reclaimed, and rehabilitated area
b) Mineral storage
within the lease for the preceding financial year. The data should be submitted in the UTM Projected Coordinate system in shp format.
Boundary Pillar
It helps in identifying the mining boundary and also helps to prevent encroachment. Unique identification numbers also mark the pillars. With the help of the DGPS, the coordinates of the pillars are noted. The Boundary pillar data should be submitted to IBM in shapefile (shp) and Excel.
Drone Survey Log Sheet
The drone survey log sheet consists of general checking fields like the airspace map, wind speed, cloudiness etc. It also contains the flight log where information on each flight including the date, place and time of operation are recorded. The drone survey log sheet should be submitted to IBM in .doc format.
Figure above, is kind of a General Log Sheet and IBM has not defined any standard format for it.
11. Submission of Data to IBM
The processed output data of the drone survey shall be submitted in soft copy only in storage media (i.e., external hard disk) on or before 1st July every year along with the Output data submission form at the following addresses.
- The Chief Mining Geologist, Indian Bureau of Mines, GM&MM Cell, 1st Floor, A- Block Indira Bhavan, Civil Lines, Nagpur- 440001, Maharashtra
- Respective Regional Offices Indian Bureau of Mines
This brings us to the end of the series. I hope this series gained some knowledge for you!
