Executive Summary
This report examines landmine and
Explosive Remnants of War (ERW) incidents in Cambodia, focusing on their
geographic distribution and the effectiveness of clearance efforts.
Utilizing two datasets (landmine incidents and fear levels reported by
clearing operators), the study highlights critical patterns affecting
local safety and development.
Our key findings indicated landmine
incidents are concentrated in Cambodia’s northwestern regions near the
Thai border and around Phnom Penh, historically conflict-heavy zones.
Despite significant efforts by organizations like CMAC and The HALO
Trust, landmines continue to pose serious risks to the people,
particularly in foraging areas, rice fields, and villages, which are
vital to the livelihoods of many Cambodians.
Clearance activities have led to a
reduction in landmine-related incidents since 2010, but residual risks
remain. The probability of injury, amputation, or death upon triggering
a landmine is still considerable, with anti-personnel and anti-vehicle
mines being the most dangerous. Continued clearance efforts and targeted
public education are essential to reducing these threats further.
In conclusion, while Cambodia has made
progress in mitigating landmine risks, ongoing education, focused
clearance in high-risk land-use areas, and resource optimization to
protect communities and support economic development are still
required.
Introduction
With Cambodia rapid GDP growth since 1998
and high tourism rates (Wikipedia, n.d.), it is important for the land
to be safe from any threats so that foreign direct investment (FDI) can
proceed smoothly, and tourists feel safe to travel in the country. In
this report, we will be investigating 2 datasets (landmine incidents
<mine.shp> and fear level
<khm_blscontaminationp_gov_cmaa.shp> by the mine clearing
operators) in detail.
In landmine incidents dataset, there are cases of landmine
incidents, location of the incidents, type of mine and injury type
(Injure, Amputation, Killed) recorded. As for fear level, there are
landmine clearing operators records of mine clearing in each location
with indication on the fear level, proximity of the landmine and land
type.
With the above datasets, we hope to understand how mine clearing
was done by the operators, possible type of mines found in the land,
type of land use in the location. Since the result of the landmine
incident dataset still shows some landmine found in 2013, we can propose
possible insight on the correlation of landmines type and landuse to
related parties for further education on detection.
Data Exploration
Before proceeding with the study, we
evaluated both datasets and found the following variables which may be
used for our studies.
Both datasets:
- geometry : This variable contains the longitude and
latitude of the villages.
- Province, District,
Commune, Village : Location of
occurrences.
- SurveyDate, Incident_D : Date of
survey and landmine/ERW incident date.
fear level dataset:
- Fear_Level : landmine/ERW fear level in the
location.
- Proximity : landmine/ERW proximity level.
- Operator: landmine/ERW clearing operators.
landmine/ERW incidents dataset:
- INJURE, AMPUTATION,
KILLED : landmine/ERW injury type and number of
victims.
- ERW_TYPE, MINE_TYPE : Type of
landmine/ERW (Anti-personal, fuse, etc)
- LANDUSE : Location type of land (Foraging area,
Rice fields, etc)
From the above variables, we will need to
proceed with the following before being able to plot any graphs.
- To convert the shp files into dataframe by using
read_sf function.
- Transform the geometry variables into lat-long coordinate system
with
st_transform. With the coordinates, we will be able to
plot choropleth maps easily on the location.
- In order to plot the Cambodia outline choropleth map, Province,
District, Commune shapefiles were download from the Open Development
Cambodia webpage. (Open Development Cambodia, 2023) function like
st_read is required to convert the coordinates into
dataframe (Cambodia_province, Cambodia_district, Cambodia_commune)
- Merge ERW_TYPE and MINE_TYPE
variables using
coalesce function.
- Convert INJURE, AMPUTATION,
KILLED variables from wide format to long format.
- Split the date of SurveyDate,
Incident_D in Year, Month, Day variables for easy
calculation and charting.
- Removal of 1913 year record in fear level dataset because of
outliner and limited data.
In addition to the above actions, there
are also some replacements in variables’ records which will be covered
in Appendix 1.
History of Cambodia
Even since the start of the Cambodia Civil
War from 1967 to 1975, landmines had been used by all Cambodian factions
to prevent advancement of troops in the region. In 1979 to prevent more
Cambodia refugees to enter Thailand, Thai soldiers were stationed to
shoot anyone who cross the no men’s land border with landmine deployed.
(Wikipedia, n.d.) Other than landmines, Explosive remnants of war (ERW)
also remained in Cambodia grounds due to long history of wars which took
place in the country.
K5 Plan
After the Cambodian-Vietnamese War from
1978 to 1979, Khmer Rouge fled and regroup behind the Thai-Cambodian
border. In order to their resurgence into Cambodia land, People’s
Republic of Kampuchea (PRK) triggered the K5 plan which included
clearing the land to leave a foraging area along the Thailand border so
that it can be watched and mined, (Wikipedia, n.d.) This plan did not
deter Khmer Rouge from entering the country and created several social
issues even until today.
Evidence of the landmine/ERW
These landmines/ERW that are used during
the Civil War and post-Khmer Rouge regime can still be seen in the below
figure even in 2009 (30 years after the Civil War). From the figure, we
observed that the major fear level is located in the north-western near
the Thailand border which we can infer that those landmines/ERW have
remained after the wars. Till 2013, there are still high fear level
landmines detected in the regions.

In the landmine incident datasets, we
identify 2 major areas highlighted in the below figure in red and blue.
Similar to fear level result above, most of the incidents occurred in
the northwestern region near the Thailand border. There is also another
area around Phnom Penh where several wars were fought. For example,
Khmer Rouge took control of the province in 1975 and invasion of Vietnam
from 1978 to 1979 into Cambodia and form rival government (PRK). We can
estimate ERW might have remained on ground due to several wars and
landmines were also deployed around the province during the wars. From
the below figure, we can observe that despite operators’ strong effort,
there are still landmine/ERW incidents that occurred in 2013.

Cambodia Fear Level from 2009 to 2012
Based on the below figure from fear level
dataset, we observed that several landmines/ERW were found in the 3
Provinces (Banteay Meanchey, “Battambang”, “KAMPONG THOM”) during the
landmine Operator surveys. There was a sharp decrease in the landmines
survey after 2012 when the landmine Operator completed most of the area
in Cambodia. However, there are still bit of underlying landmines/ERW
which are found in other smaller villages.

In the top 3 Province found with
landmines, we observed that fear level in the provinces were generally
Medium and High with 2 type of landmine proximity, Near and Very Near.
The ratio of the Near proximity is generally higher than Very Near in
both categories. This indicated that the damage of the landmines/ERW to
the people who triggered it was still lethal.

Major Landmine Clearing Operators
Based on the fear level dataset, there are
four Operators assisting in the landmine/ERW clearing activities in
Cambodia. From the below figure, CMAC and The HALO Trust are the main
players in the clearing activities in Cambodia and their peak activities
were in 2010. We estimated that these surveys were conducted near the
Thai borders where most of the landmines are deployed.

Cambodian Mine Action Centre (CMAC)
CMAC, established in 1992, was one of the
main organizations helping to make Cambodia land safe for residents in
Cambodia and development. In the below figure, we observed that the main
activities for CMAC was found in the northwestern of Cambodia and
surveys were mostly finished in 2011. The focus was then shifted to
another border of Cambodia as shown in 2012. One of the possible reasons
for the shift in focus might be due to historical records of
landmine/ERW incidents in 2005 where several injuries were found around
Phnom Penh.

The HALO Trust (HALO)
The HALO Trust is a global humanitarian
non-government organisation which also helps to clear landmines left
behind by wars and other conflicts. They also started their activities
near the Thai border from Koh Kong to Preah Vihear and progressively
move through the country based on locals’ request calls. (The Halo
Trust, n.d.) In the below figure, their activities were shifted through
the country in the central region where the land can be used for the
people livelihood after clearance.

Landmine/ERW incidents trend from 2005 to 2013
In the below figure, we observed that
there was a significant decrease in the landmine/ERW incidents after the
Operators’ clearance activities, but the ratio of the landmine/ERW
effects is still similar between 2013 and 2005. This mean that there
will still be 19% chance of amputation, 61% chance of injury or even 20%
chance of get killed when triggered any landmine/ERW in 2013.

Popular Landmine/ERW area in Cambodia
In order to effectively educate the people
in Cambodia on possible danger area, we summarize all the landuse area
where incidents occurred. In the below figure, there are 10 types of
landmine/ERW found in Cambodia and top 3 most popular landuse types were
Foraging area, Village or urban/built-up area, Rice Field. From the
results, we can estimate that landmines were usually deployed at
Foraging area and Rice field because of better line of sight of any
enemies especially when explosion occurred, Fuse and Mortar rounds are
found in Village or urban/built up area because of the ongoing prolong
wars in the country.
These locations were actually dangerous to the people of Cambodia
because their livelihood depend on agriculture mainly. They might be
exposed to high risk when managing the farms (Rice field) and have
difficulty finding new areas for farming (Foraging area).

Top 3 Landuse Study
In the below figure, anti-personal mines
were used more in the foraging area, rice field than in the village or
urban/buildup area. One of the possible reasons might be it is easier to
deploy in lesser people’s environment and injuries on allies could be
kept minimum. Another reason might be to reduce the watchout points
where intruders who stepped on the landmine would be alarmed with
explosion and easily spotted. Due to the open field condition of rice
field where vehicles can advance easily, anti-vehicles mine could also
be found to prevent quick advancement of troops. Lastly in order to
prevent troops advancement and reduce troops quantity, area damage
weapon mortars, fuses were usually used in the war and ERW of the shell
and fuses might remain after the war end. All of these are dangerous
when people touch or trigger it.

Injuries caused by major types of landmines/ERW
In the below figure, 59% of the
anti-personnel landmine triggered by victims will most likely be
amputated. Depending on the distance to the landmine and the blast, they
might even get killed within the blast proximity. The next dangerous
landmine will be the anti-vehicle landmine which is larger than
anti-personnel landmine and the blast radius is bigger. This resulted in
33% chance of victims to be killed when triggered it. As for the ERW,
mortar, it had 26% chance of killing the victims because of high
explosive blast in nature and it may be triggered unknowingly which make
it more dangerous for people in Cambodia. Lastly, for fuse which is less
explosive in general had 20% of amputation chance when triggered by the
victims.

Type of landuse found in most Landmine/ERW Province (2005)
Since 2005 is one of the largest amounts
of landmine/ERW incidents, we evaluate the top 3 province incidents
during that year as a benchmark. From the below figure, we observed that
the incidents occurred mostly at the Foraging area (32% to 50%), Village
or Urban/built-up area (14% to 50%) and Rice field (9%). This mean that
it is risky for people of Cambodia to search for food in the Foraging
area, managed their rice field and wandered around in the village.

Sign of reduction in Landmine/ERW incidents
As Agricultural activities are the main
source of income in Cambodia, it is important to keep the land safe from
any landmine/ERW. Luckily through the years of mine clearing by the
Operators, we do see a great reduction in incidents in the below figure.
However, we should not feel complacent about the result because there
were still chance for the people of Cambodia to encounter landmine/ERW
during their daily activities like farming or clearing the foraging area
for agricultural activities or other development.

Landmine/ERW incidents still occured after 24 years
The below figure showed landmine/ERW
incidents still occurred in the 3 major landuse type (Foraging area,
Rice field, Village/urban built-up area). This means that the country is
still at risk of landmine/ERW incidents. With the inflow of foreign
direct investment (FDI) in construction and real estate, rapid
development of land will take place. Therefore, it is important for
workers or people of Cambodia to learn how to live with the risk and
understand the proper procedure on clearing one when they encountered
it.

Conclusion
The study reveals that while achieving a
completely mine-free Cambodia is unlikely, several steps can be taken to
mitigate the risks posed by landmines and ERW. First, continuous
education of local communities is essential to help people recognize and
respond to these threats, especially in high-risk areas. Public
awareness campaigns and training should be tailored to different age
groups to ensure maximum effectiveness.
Operators should also prioritize clearance
efforts in the top three land-use areas, particularly foraging areas,
rice fields, and villages so as to safeguard livelihoods and support
agricultural activities. Further improvement in landmine risk reduction
can be achieved by incorporating demographic data into training
programs, enabling more targeted safety education.
Additionally, monitoring landmine
incidents beyond 2013 can also help refine clearance strategies,
allowing operators to focus resources more effectively and adjust their
efforts based on emerging trends. This data-driven approach will
optimize resource allocation and enhance the safety of communities
across Cambodia.
RMarkdown File Attached Below
Appendix 1 : Data Cleaning Issues
In order to preserve the coordinates in
the datasets, we will need to import the shapefile into R with
read_sf command below.
# Load datasets with geometry in environment
cambodia_fear.df <- read_sf(dsn = "./mine/khm_blscontaminationp_gov_cmaa.shp")
cambodia_mine.df <- read_sf(dsn = "./fear/mine.shp")
str(cambodia_mine.df) # Check data frame
str(cambodia_fear.df) # Check data Frame
st_transform` was used to obtain the
longitude and latitude from the geometry variables.
# Transform the geometry into lat-long coordinate system
cambodia_fear.df$geometry <- st_transform(cambodia_fear.df$geometry,crs=4326)
cambodia_mine.df$geometry <- st_transform(cambodia_mine.df$geometry,crs=4326)
To draw the country outline as Choropleth
map, we need to st_read the shapefiles of province,
district, commune obtained from Open Development Cambodia (2023)
webpage. With the coordinates, we will be able to create the Cambodia
base map with province, district, commune details.
# Read Cambodia Province, District, Commune Map
cambodia_province <- st_read("basemap_province.gpkg")
cambodia_district <- st_read("basemap_district.gpkg")
cambodia_commune <- st_read("basemap_commune.gpkg")
Since ERW_TYPE and MINE_TYPE belong to the
same categories, we merge them into one variable as TYPE variable. It
will be easier to plot any charts to understand which type of
landmine/ERW injured the people of Cambodia.
# Merge ERW & Mine Type in one column
cambodia_mine.dfe <- cambodia_mine.df %>%
mutate(TYPE = coalesce(ERW_TYPE,MINE_TYPE)) %>%
select(-c(ERW_TYPE, MINE_TYPE))
Long format is usually preferred during
plotting charts. Therefore, we have to use pivot_longer on
mine dataset to combine different type of injury (AMPUTATION, INJURIED,
KILLED) into one variable. In this way, it will be easier to plot any
column chart.
# Convert Wide Format to Long Format
cambodia_mine.dfl <- cambodia_mine.dfe %>%
pivot_longer(cols=13:15, names_to="INJURY_TYPE", values_to="CASES")
For easier time series plot, we will split
the date variables into 3 variables (Year, Month, Day). In this way, we
could easily call the required date variables for plotting any time
series plot. On the safe side, we will define these variables as Integer
to prevent any decimal points from occuring.
# Split Dates into Year, Month, Day
cambodia_mine.dfle <- cambodia_mine.dfl %>%
mutate(Incident_D = as.Date(Incident_D), year=year(Incident_D),
month=month(Incident_D), date = day(Incident_D))
cambodia_fear.dfe <- cambodia_fear.df %>%
mutate(SurveyDate = as.Date(SurveyDate), year=year(SurveyDate),
month=month(SurveyDate), date = day(SurveyDate))
# Set year and month as Integer
cambodia_mine.dfle$year <- as.integer(cambodia_mine.dfle$year)
cambodia_mine.dfle$month <- as.integer(cambodia_mine.dfle$month)
cambodia_fear.dfe$year <- as.integer(cambodia_fear.dfe$year)
cambodia_fear.dfe$month <- as.integer(cambodia_fear.dfe$month)
Once all the datasets are arranged
properly, we will need to review the class type of each variable and
search for any missing or wrong data in the records of the variables.
The commands below were used to check the class type and some of the
records for both datasets. Sometimes, weird records might be short
during str() check.
# Verify class for each variables.
str(cambodia_mine.dfle)
str(cambodia_fear.dfe)
head(cambodia_mine.dfle)
head(cambodia_fear.dfe)
During data checking, we found “(blank)”,
“Unknown” records in some of the variables and will perform
gsub() to replace it to “NA” for easier identification. We
also remove the row which year is 1913 because there are insufficient
similar records in the dataset and it will be treated as outliner during
any plotting of the charts. As country knowledge is required for
replacing any NA records correctly and the NA records are small sample
size, we will not take any actions in this study.
# Replace "(blank)" with Null in variables.
cambodia_fear.dfe$Fear_Level <-
gsub(pattern = "(blank)", replacement = NA,
x=cambodia_fear.dfe$Fear_Level, fixed = TRUE)
cambodia_fear.dfe$Proximity <-
gsub(pattern = "(blank)", replacement = NA,
x=cambodia_fear.dfe$Proximity, fixed = TRUE)
cambodia_mine.dfle$Landuse <-
gsub(pattern = "Unknown", replacement = NA,
x=cambodia_mine.dfle$Landuse, fixed = TRUE)
cambodia_mine.dfle$TYPE <-
gsub(pattern = "Unknown", replacement = NA,
x=cambodia_mine.dfle$TYPE, fixed = TRUE)
# Drop row which year is 1913
cambodia_fear.dfe <- cambodia_fear.dfe[-which(cambodia_fear.dfe$year=="1913"),]
In order to plot any column chart with
percentage, we will need to tabulate the results in a newly constructed
dataframe before any chart can be plotted. In the below code, we perform
2 group_by so that we can summarize by year and Injury_Type with no
duplicate records. After subtotals were obtained for each Injury_type,
we will be able to calculate the percentage against the year
total.
# Construct Grouped Data by year, Injury Type and calculate the percentage.
cambodia_mine.consolidate <- cambodia_mine.dfle %>%
group_by(year, INJURY_TYPE) %>%
summarize(N = n(), subtotal = sum(CASES), .groups = 'drop') %>%
ungroup() %>%
group_by(INJURY_TYPE) %>%
mutate(Total_injury_type = sum(subtotal)) %>% # Total by INJURY_TYPE
ungroup() %>%
group_by(year) %>%
mutate(Total_year = sum(subtotal),pct =round((subtotal/Total_year)*100,2))