1. Boac River Update
(As of February 2013)

2. BACKGROUND
 Upon Marcopper’s cessation of mining activities at its Tapian Pit in
1991, a 2.25 km. drain tunnel (measuring 7' x 8‘) that was used to
drain the water from the pit was sealed by caving it and a three (3)
meter thick concrete plug was constructed at a section located 92 m.
from the outlet portal.
 On March 24, 1996, the rock around the 3-meter concrete plug was
fractured and the plug failed. Approximately 1.6 million cubic meters
of tailings was released to the 26-kilometer Boac River.
 The sealing of the tunnel was the priority activity right after the
spillage. The first plug of the tunnel, eighty (80) meters of bitumen
grouting, was completed in October 18, 1996. A second/engineered
final plug was completed in August 1997. Independent experts
certified the As Built Report of the Final Plug in December 24, 1997.
The final plug is certified to last a thousand (1,000) years.

3. WHY WAS THERE NO CLEAN-UP OF THE BOAC RIVER?
 No Government Approved Clean-Up and Rehabilitation
Plan for the areas affected by the 1996 Tailings Incident for
a number of reasons:
1.
The unresolved major differences among stakeholders on the
final option for the disposal of the spilled tailings;
2.
Inability of the National Government to exercise its
State responsibility to render a decision on the Best Clean-up
Option despite the availability of relevant scientific and
technical studies and information for a decision to be rendered
and implemented;
3.
Persistent demand from the LGU, Church leaders, and local
NGOs of Marinduque for a consensus among all the
stakeholders on the matter of deciding on final clean-up
option;

4. Yet, despite all the squabbling by stakeholders, THE BOAC RIVER IS
BACK WITHIN PRESCRIBED ENVIRONMENTAL LIMITS.
“Observations of the use of the Boac River have revealed
that the public has returned to many of the traditional
uses
of
the
river.
These
include
river
quarrying, fishing, clothes washing and general road
access.”
- MGB COMPLETE STAFF WORK REPORT,
Marcopper Mining Corporation 1996 Tailings Spillage
(Report as of February 15, 2013)

5. “Five (5) year monitoring of the river has shown gradual recovery
of the Boac River. While additional tailing materials remains mixed
with gravel in levee banks, this material is not affecting the
river environment from a chemical or biological perspective.
Similarly, the tailings mixed with gravel, which is encapsulated in the
dredge channel is removed from the surrounding environment and
presents a very low risk of environmental impact.”
- MGB COMPLETE STAFF WORK REPORT,
Marcopper Mining Corporation 1996 Tailings Spillage
(Report as of February 15, 2013)

6. “In general, all the scientific studies cited above on the
potential effects of MMC tailings Spill suggest the remaining
tailings in the Boac River has no significant broad scale
environmental toxicological impacts. However, we feel that the
water quality will improve further once the remnant mine tailings
are finally removed and disposed appropriately.”
- MGB COMPLETE STAFF WORK REPORT,
Marcopper Mining Corporation 1996 Tailings Spillage
(Report as of February 15, 2013)

7. April 2009

8. April 2009

9. March 2010

10. April 2011

11. May 2011

12. April 2011

13. May 2011

14. May 2011

15. May 2011

16. May 2011

17. April 2012

18. April 2012

19. June 2012

20. July 2012

21. October 2012

22. November 2012