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IMSMA and SHAs

What is the Standard IMSMA Functionality?

IMSMA stores LIS data in a relational database, using a Microsoft Access client application and a specified quality limit (SQL) server application. IMSMA also provides mapping functionality for capturing and displaying geographic data using the GIS ArcView. IMSMA is used for capturing, manipulating and displaying the LIS data (Figure 4).

Recording SHAs

The location and attribute data of the community are recorded in the two tables “tblCity” and “tblSurvey1.” The viewing point location and data on the SHA are recorded in the table “tblSurvey1MinedArea.”

Displaying SHAs

The community reference point and the viewing points are presented in the GIS as shown in Figure 5. In the example, the SHA starts from the viewing point, which is on a tarmac road. The reported size of the SHA is displayed as a circle of the same area as the SHA, and no further reference to the extent, shape or geometry is displayed or stored.

For simplicity in the following discussion on how IMSMA management of SHA data is extended, it is assumed that the starting and viewing points are identical.

How may IMSMA be Extended for Better SHA Mapping?

Introducing Boundaries

When the SHA boundary is recorded in the field (using the procedure described above as visual inspection and mapping), the description of the boundary can be recorded in a GIS and also in IMSMA. The coordinates of the boundary may be captured in one of two ways in the field: the boundary is drawn directly on a topographic map or turning point coordinates are fixed along the SHA boundary using GPS in the field.

A small adjustment of how the IMSMA tables are used is required in order to capture and store these boundaries in IMSMA. The part of IMSMA that is designed to LIS SHA data does not provide any container for coordinates other than those of the viewing and starting points. Boundary coordinates and topology can, however, be captured using the parts of IMSMA that are designed for dangerous areas or minefields.

For example, in the Thailand LIS data pool, most SHA data is recorded in the “tblSurvey1MinedArea” table and the SHA boundary coordinates recorded as the perimeter under the “tblMinefield” table. Records of the two tables were linked using the global unique identifier (GUID) column in the “tblSurvey1MinedArea” table and a User Defined Field in the “tblMinefield” table.

If the SHA boundaries are recorded by GPS, coordinates can be transferred directly to the GIS. If SHA boundaries are drawn on topographic maps, the coordinates can either be digitised directly on the screen on top of scanned geo-referenced topographic maps or by using a digitising tablet. IMSMA provides the capability to capture the coordinates from the GIS.

Introducing Many Communities Impacted by the Same SHA

At times, the survey teams discover that a number of communities are impacted by the same SHA. Under these circumstances, traditional LIS methodology and use of IMSMA would suggest that data on the same physical area, the SHA, are recorded as many times as there are impacted communities claiming this area. The consequences of this procedure may be that SHA data become duplicated, which is in particular a problem in terms of multiplying SHA size estimates.

Also, this may be difficult for users of the data to assess if the area to clear or mark is the same area or a number of separate areas. The problem is addressed in the Thailand LIS by separating the impact description data and the physical description data for the SHAs, as illustrated in Figure 7.

In the example in Figure 7, two communities report to be affected by the same SHA (identification number 1). However, communities A and B report different impacts from the SHA, since they would access different resources in the SHA. Community A reports blocked access to forest resources, such as firewood and food. Community B reports blocked access to water, in addition to forest resources. Thus, the impact may be different from community to community. However, the physical properties of the SHA are the same.

The physical data, such as terrain, vegetation and SHA boundaries, should only be recorded once, in order or to avoid duplicates and to make clear to users of LIS data whether the communities reported on the same SHA or different ones.

In the field, the procedure requires recording the SHA boundary and community locations on a topographic map, in order to describe the SHA and its impact on different communities. Also, coordination of visual inspections and survey reporting, if different survey teams visit different communities affected by the same SHA, is required to decide if the survey should report one common SHA or individual SHAs.

In IMSMA, the SHA data is entered in two different tables. SHA impact data is entered into the “tblSurvey1MinedArea” table and SHA physical data is entered into the “tblMinefield” table. This provides the capacity for managing data on multiple impacted communities and one single SHA. It is worth noticing that this adjustment in the use of IMSMA is identical to that required for capturing and displaying SHA boundaries, as described above.

Introducing Linear Features

A major problem in many mine/UXO-infected countries is caused by the use of landmines at or around infrastructure including transportation networks. Mines are often deployed to protect the facilities, to stop people from using or accessing the facilities, or just to create a sense of fear.

After the conflicts end, the safe reopening and rehabilitation of these facilities may have a tremendously positive impact on the population’s social and economic development. For Angola, the most important mine-related problem they had to address for creating development, reintegration and reconciliation was the reopening of roads, railroads, power, telecommunication and water supply networks.

Common to many types of infrastructure is that they are best mapped as a linear feature—a line (with a certain width) with start and end points and a set of vertices defining its shape—on the scale and accuracy typical for non-technical surveys. The current LIS methodology is very limited in terms of mapping these linear features and assessing their impact on socio-economic development. However, by recording these features on topographic maps and in IMSMA, their impact is presented and assessed in a better way. Further assessment would typically include recording these features at national or regional levels (not only which communities linear features may serve) and the socio-economic development potential in a wider context.

Because no examples of a mapped SHA road were available from the Thailand LIS nor were any IMSMA-produced graphics from the Angola general survey, Figure 8 shows a hypothetical example of how linear features (a suspected road) can be captured in IMSMA and how they can be presented in the IMSMA GIS.

Linear features can be stored in IMSMA under the minefield module. However, they do not display properly if not recorded as polygons. This can be done by first digitising the line as ArcView graphics, then creating a buffer of an appropriate size, for example five m, and exporting this polygon graphic to the minefield perimeter module in IMSMA.

Where the linear SHA feature affects more than the community can be easily displayed. Furthermore, it is easy to present how the blocked feature, such as the road in Figure 8, links to other parts of the network that is in use. The suspected road, in the example, provided access to and from the outside world for three of the four communities before it was suspected of containing mines. Today these three communities are accessible by foot only. The fact that this segment of the road network is not in use also cuts off circulation between the west and east, which, on a regional scale, is an obstacle to further development.

Using SHA Data From LISs

By nature, non-technical landmine surveys collect data on SHAs from a variety of sources. These sources, which mainly are informed individuals, provide information that varies greatly in terms of reliability and completeness. No mechanical investigation is deployed in order to confirm or discard the information, nor to objectively assess the reliability and completeness of the information. As a consequence, non-technical survey data on SHAs could be anywhere between a complete and precise description of every single explosive item present in the SHA to the description of the interviewees’ vague feeling or fear that a relatively unbounded area has landmines or UXO and, thus, is an SHA. It is important that this aspect is considered and properly understood by those who need to display or use SHA data from non-technical surveys.

The description of the SHA extent may range considerably in terms of reliability and completeness, and the three methods used to capture SHA (described above) range in detail. Bulk-size estimates of a country, region, or even a community are frequently referred to and used as descriptors of the landmine or UXO contaminated area. This method of using the non-technical survey size significantly exaggerates estimations of the size. Furthermore, it may nourish a paralysing baseline view of the problem and further action, as the extent reported from most countries cannot be dealt with efficiently with the methods of clearance or area reduction today.

Thus, care must be taken when using non-technical survey data on SHAs as a basis for strategic planning or detailed resource allocation for clearance or area reduction operations.

Improving SHA Data and Their Use

Measures to overcome or reduce the problems pointed out above have been developed and implemented during some non-technical surveys. The key developments are:

• Strengthening the visual inspection and introduce a reasonable mapping capacity within the survey field teams. If not all teams are “upgraded,” specialised mapping teams are required to revisit the high-impact location.
• Introducing procedures during the visual inspection that reconfirm and improve the descriptive SHA data with the help of key informants, maps and an understanding of the local conflict and the logic of ordnance use in the area.
• Introducing assessment procedures during the visual inspection that classify an SHA according to its possible clearance duration and marking potential.

Marking Potential and Clearance Duration

With basic training and clear rules for the field assessment, survey teams are able to categorise SHAs in order to give some direction regarding the possibility for marking and clearance. For example, the survey teams categorised marking potential and suggested clearance duration of each of the 933 SHAs mapped by the Thailand LIS. The classes and criteria applied during the visual inspection were as described below.

Marking potential is assessed by investigating if SHA boundaries are well-defined and may be safely marked with warning signs. Three response categories are used: all sides, some sides or not at all.

Suggested clearance duration is assessed by investigating how well defined the SHA is and considering its size. Three response categories are used:

• Short duration requires the SHA to have well-defined boundaries and a size less than 100 sq m.
• Medium duration requires the SHA to have well-defined boundaries and a size less than 10,000 sq m.
• Long duration is applied to other SHAs that are poorly defined and/or larger than 10,000 sq m.

These additional measures are introduced in the field component of the survey instrument and personnel training.

IMSMA Filtering and Display

Further measures have been and should be more developed in terms of data management and analysis. Rather than using crude SHA data from non-technical surveys, data should be filtered for reliability and completeness. Such filters would, for example, be applied to selected SHAs, when size estimations are appropriate for further use in strategic planning, or when quality of description and degree of risk call for deployment of recognisance teams ahead of clearance or area reduction operations. Conditional display functionality for SHA polygons could improve how the data is presented in the GIS, where SHA display symbology could depend on SHA size and, if possible, also how well the boundaries are defined.

Conclusion

The LIS provides detailed and very valuable data on SHAs, covering a high number of communities and SHAs in a relatively short time. Although indispensable to further mine action, the data should be used with the appropriate care and knowledge of the procedures used.

Three different levels of SHA mapping are described in terms of field procedures and data management using IMSMA. Where reasonable topographic maps are available, SHA data should be collected by the visual inspection and mapping procedure in the field by map-literate survey teams. The same procedure should be used to record linear features, such as roads and power lines during non-technical surveys.

IMSMA is able to capture, manage and display the introduced SHA extended geographic data by an adjustment in its use. This provides for management of SHA boundaries, the structure of many communities impacted by one SHA and linear SHA features such as roads. However, gains would be high if IMSMA could provide this functionality directly.

*All graphics courtesy of the author.

Endnotes

1. The LIS Glossary definition of Suspected Hazard Area is a “suspected landmine and/or UXO area as identified by key informants during the community interview process.”
2. The rule of thumb is used to estimate distances:
   1. Point a straight arm against the identified point whose distance you are to estimate (point A) and aim your thumb at this point using your right eye only:
      
   2. Keep your arm fixed and aim the thumb using the left eye—identify the position of the point you are now aiming at located perpendicular to your line-of-sight (point B):
   3. Estimate the distance to point A from the viewing point as 10 times the estimated distance between points A and B. The factor of 10 may be adjusted depending on each person’s arm length and distance between eyeballs.
3. Triangulation is used to calculate the position of a remote point by measuring the direction to the remote point from two different points of known location (e.g., recorded by GPS).

Contact Information

Rune V. Engeset
Survey Special Advisor
Survey Action Center
6930 Carroll Avenue, Suite 240
Takoma Park, MD 20912
USA
Tel: 301-891-9192
Fax: 301-891-9193
E-mail: sac@sac-na.org
Website: www.sac-na.org