against mining in Rapu-Rapu
A. Acid Mine Drainage (AMD) as a consequence of mining activities
in sulphide-bearing rocks is confirmed both at Pagcolbon (present
mining exploration) and upper slopes of Sta. Barbara (formerly
known as Carogcog Saday representing past and abandoned mining
site of Hixbar Mining Co.).
is water polluted with high levels of iron, aluminum and sulfuric acid.
It appears orange or yellowish-orange or orange-brown in color due to
high levels of iron content. It also smells like rotten egg which is
due to the emitted sulfur dioxide. AMD occurs when the mineral iron
pyrite (FeS2) is exposed to air and water.
2FeS2 + 7O2 + 2H2O ----> 2 FeSO4 + 2H2SO4
the reaction forms iron sulfate (FeSO4) and sulfuric acid (H2SO4). Such
reaction is hastened by the presence of a bacteria (Thiobacillus thiooxidans)
and converts sulfur in a reduced form to sulfate (Jackson and Jackson,
Associates of the INECAR conducted a scientific study on the potential
for AMD in the island of Rapu-Rapu during the second week of May, this
year. Two professors and two college teachers composed the team. The
two professors are: Dr. Emelina G. Regis (the undersigned) and Dr. Melanio
M. Regis. The two other teachers are: Engr. Irma Medrano and Ms. Au
Azurin. A brief educational background and their expertise are provided
in Annex C. In this study, three sites were investigated: a) Creeks
at the Hixbar mining Area (Carogcog Saday) and immediate surroundings
representing impact of past and abandoned mining activities, b) Creek
at Pagcolbon and surrounding area representing impact of the present
Lafayette mining exploration and c) Creek at Sta. Barbara and the adjacent
barangay proper. This creek (c) is not directly connected to the contaminated
creek from the Hixbar mining area and represents clear water creek.
[please see Figures 1, 1a), 1b) and 1c) in attached map]
1 Location of the Study Sites: 1.) Creeks at Hixbar mining Area
2.) Creek in Lafayette mining area 3.) Creek at Sta. Barbara
Mina creek at Hixbar in Carogcog Saday/ #1 in Map
1a) Creek at Pagcolbon just below the field office and processing
area of Lafayette. #2 in Map
Part of the clear water creek at Sta. Barbara. #3 in Map
findings of the study show acidic water and soil in both the Hixbar
(Site 1) and Pagcolbon (Site 2) creeks; neutral pH was recorded for
the creek at Sta. Barbara (Site 3). [Please see Annex A for the values:
neutral pH is 7.0; the lower the number the more acidic the material,
the higher the number, the less acidic but the more basic/alkaline the
material]. Thus, the initial suspicion of Acid Mine Drainage (AMD) occurring
in the area is confirmed. AMD is occurring in the 2 creeks originating
from the Hixbar area; AMD is also occurring in the creek at Pagcolbon
which is located just below the field office and processing area of
Lafayette Mining Company. [Please see Figures 2 to 6a) below]
2: Contaminated creek (Pulang Salog) at Hixbar 120 meters
above sea level (asl)
3: Contaminated pond at Hixbar mining 300 meters asl.
Orange-Brown water and silt indicating AMD, coming out of a
canal inside the field office of Lafayette Mining company (taken
Jan. 23, 2000)
View of the field office (indicating by a red arrow) of Lafayette
Mining Co. just above the contaminated creek (picture taken
May 9, 2000)
Contaminated creek at Pagcolbon just below the field office
and processing area of Lafayette Mining Company at 70 m asl.
(picture taken May 9, 2000)
Part pf the contaminated creek mentioned in Figure 6. Note the
yellowish-orange-brown condition of the creek's botton sediments
and coating on rock surfaces.
reported earlier, AMD is a "perpetual pollution machine" because of
its potential for long term devastating impacts on rivers, streams,
and aquatic life (http://www.miningwatch/ emcbc/library/amd_water.htm).
This acid dissolves the heavy metals such as lead, zinc, copper, arsenic,
mercury and cadmium, found in waste rocks and tailings. The presence
of certain bacteria is able to increase the rate of the reaction (http:/biology.usgs.gov/s+t/SNT/
present, the first world countries maintain that there is no effective
treatment of AMD with existing technology (Environmental Management
Council of British Columbia on line: http://www/miningwatch.org/emcbc/library/amd_water.htm)
. Below are some examples of proposed treatments/remediation and their
- The proposed
treatment by seawater enhances the released of heavy metals. Hamelink
(1994) reported for instance that in the dredged mud of Hamburg Harbor,
1.3% of the total Copper (Cu) was released upon the addition of seawater.
Likewise, in a experiment using seawater treatment, 9.1% of the total
Zinc (Zn) was also released to the surroundings.
- In the case
of Deep Sea Tailings Placement (DSTP) which is the intended method
of Lafayette [ TVI Press Release October 13, 1999], the effect is
on the biodiversity of marine organisms.
In the report provided by Environment Canada (Briefing Document on
Metal Mine Submarine Tailings Disposal [March 22,1996]), to the Environmental
Mining Council of British Columbia, Canada, the BHP Minerals' Island
Copper Mine near Port Hardy had been using marine dumping for its
wastes for years until its closure in 1996. The effect on the aquatic
life of the sea floor at the site was low abundance and diversity
of organism (http://www.miningwatch.org/emcbc/library/amd_water.htm).
With the present situation of dwindling fishery resources in the Philippines,
we cannot afford to risk destroying what is left of our marine resources
because food security is a basic necessity. Even in the absence of
jobs, when food is abundant in a resource, our people could still
- If the method
is to prevent exposure to oxygen by submerging the waste rock or tailings
under water, the water cover and structure of the dam must be made
strong enough to withstand geologic hazards such as an earthquake.
In high seismic area, the potential for breaking the dam structure
and cover is very likely (http://www.miningwatch.org/emcbc/library/amd_water.htm).
Figure 7 shows that the island of Rapu-Rapu has one existing fault
in the area crossing Binosawan-Malobago points between the Western
Deposit and Main Deposit. Any seismic activity strong enough to move
this fault can break the cover and dam structure and release toxic
metals to the surroundings and eventually to the sea. Perhaps this
method is possible in Australia and other large continents that do
not experience earthquakes.
- Other covers
(wet and dry) being proposed by Nick Currey (1998) is still in the
trial stage. Wet cover is done by placing acid producing rocks under
water to reduce contact with oxygen. However, this method also promotes
an anoxic (no oxygen) condition that encourages the growth of anaerobic
bacteria forming H2S. As a consequence, another environmental problem
is created which is pollution (both air water and soil, the latter
two are by wet deposition) through the release of atmospheric sulfur.
(Manahan, 1994). Furthermore, where sulfide formation occurs, the
sediments become black due to the formation of FeS. (Figures 8 and
8: Black coating on the surface of exposed rocks at about
300m. asl in Hixbar Mining area.
9: Black coating on a man-made structure at the bank of
Pulang Salog in Sta. Barbara at 120 m. asl
- The use of Sulfate
Reducing Bacteria (SRB) for active treatment of contaminated groundwater
(from mines) [Robertson, 1998] cannot solve the problem of heavy metal
contamination. SRB is able to methylate heavy metals such as mercury
(Manahan, 1994; Jackson and Jackson, 1996) making them readily absorbed
by plants and eventually remobilized through the food chain. The methylation
of mercury in aerobic and anaerobic forms for instance increases its
toxicity, posing a danger to living organisms including man.
- Lastly, remediation
is very expensive so that mining companies tend to disappear after