By J.K. Jensen, Office of Pesticide Programs, USEPA
The United States Agency for International Development (USAID) has been involved in disposal operations in Pakistan and the Niger and has made reconnaissance visits (feasibility studies that provided site-specific, practical disposal recommendations) to Guinea-Bissau and El Salvador.
In 1987, USAID sponsored a technical evaluation
team to travel to Pakistan to study how the unwanted, overaged
pesticides stored throughout the country should be handled. The team
visited 28 storage sites in the Punjab and greater Karachi area and
estimated that they contained a total of 5 000 tonnes of pesticide
products and 3 000 tonnes of contaminated materials that required
disposal. The team recommended consolidation of stocks and disposal
using one of three technologies: a lined landfill, estimated to cost
US$8.3-8.4 million; a transportable incinerator, estimated to cost
US$17.5-17.6 million; and a cement kiln (no cost estimated).
Most of the pesticides for disposal were acquired
in the 1970s by the Government of Pakistan in support of its
programme for free or subsidized distribution. The anticipated
demands never materialized and great quantities accumulated in
storage. In 1980, the government's new agriculture policy started to
withdraw subsidies for pesticides and to shift pesticide procurement
to the private sector, resulting in improved acquisition of
pesticides over the long term. The shift to the private sector,
however, combined with the government's policy of not allowing the
use of pesticides shelved for more than two years, significantly
contributed to the huge stocks of overage pesticides that require
disposal.
Because of the inherent long-term monitoring
problems with lined landfills and the limited portability and
potentially harmful emissions of transportable incinerators, the
Office of Foreign Disaster Assistance of USAID decided to sponsor a
pilot project in a rotary cement kiln, with the intention of
demonstrating this technology for use in developing countries.
The objectives of the demonstration were to show
that: a cement kiln destroys pesticides efficiently and completely;
the cement product is in no way affected by the process; and stack
gas emissions are within the range of established standards. One of
Pakistan's most modern cement factories, located at Dera Ghazi Khan,
the Punjab, was the site of the USAID-sponsored pilot pesticide
disposal project. With the agreement of the Environmental Protection
Agency of the Punjab and the Ministries of Agriculture, Production
and Finance, 13 776 l of organophosphate and 2 940 l of
organochlorine pesticides as well as 200 l of an amide were collected
from seven storage sites in November 1989. The pesticides were burned
during the normal process of cement making in December 1989.
Project planning involved an environmental
assessment and logistics plan. Collection and transport were preceded
by safety training of workers and the pesticides were injected into
the burning zone as a "cocktail"; the organophosphates at a rate of
up to 3 l a minute and the organochlorines at a rate of 1.3-2 l a
minute. The burn itself was uneventful and was accomplished over the
course of five days. The costs were not calculated, as this was
solely a pilot burn.
A total of 16 916 l of pesticides were collected
over a three-day period from seven stores in the Punjab and
transported to a cement kiln where they were burned intermittently
over the course of five days. Analysis showed that emissions of
pollutants regulated by the Environmental Protection Agency of the
Punjab did not exceed agency standards. Destruction removal
efficiency results were very close to incinerator standards in the
United States. Analysis of process samples (dust and clinker) was
excellent and the cement product was free of detectable
contaminants.
The following recommendations are made for future
test burns:
In 1988, the USAID office in the Niger was
approached by the Worldwide Fund for Nature with a report of leaking
dieldrin barrels at a site near the Tamgak nature reserve in the
northern Niger. The report concerned old stocks of pesticide for
locust control. In 1989-90, USAID, in collaboration with the
Government of the Niger, safely centralized known dieldrin stocks at
two locations in the Niger and the Royal Dutch Shell Companies
(Shell) then suggested that dieldrin be removed from the Niger and
destroyed at a commercial incineration facility. This resulted in the
Niger Dieldrin Disposal Programme which was a joint effort of USAID,
the Government of the Niger, Shell and GTZ. The programme, which took
place over a 15-month period in 1990-9 litres, collected, removed and
safely destroyed 56 000 litres of dieldrin held in the Niger.
The operation consisted of three phases: the
collection of information and a field assessment visit conducted and
financed jointly by Shell and USAID; the development of the
preparation of the actual disposal plan, an environmental assessment
and procurement of delivery contracts for the collection/shipping
tanks (isotanks) and support equipment; and the actual collection and
consolidation operation that began in mid-May 1991.
The 56 000 litres of dieldrin left Agadez for
Lomè, Togo on 6 June 1991. Political problems in Togo
prevented the direct routing of the convoy, made up of four isotanks,
one freight container and four support vehicles, to Togo but, in
spite of this, the dieldrin did arrive at the port in Lomèvia
Benin on 18 June and was loaded on to a ship bound for Europe on 26
June 1991. Incineration of the dieldrin was completed in the
Netherlands by the middle of August 1991. There were no significant
technical problems in the collection and movement of unwanted
pesticides from extremely isolated locations, such as northern Niger,
to Europe for incineration.
The full cost of the Niger programme was
approximately US$9.41 per litre of dieldrin destroyed. At least 30
percent of this amount was associated with the first-time development
of a disposal programme and an additional 15 percent represented the
cost of transporting the tanks and supplies from the coast in
Lomè, Togo, to Agadez, the Niger, and back (approximately 4
200 km round trip).
The following lessons were learnt for future
disposal operations:
In June 1990, the Government of Guinea-Bissau
requested technical assistance from USAID on the importation, storage
and handling of pesticides and on a feasibility study of disposal
options for unwanted pesticides and their containers. Most, if not
all, of the pesticides in Guinea-Bissau were donated by multilateral
and bilateral organizations and the European Community. Generally,
these pesticides had been stockpiled in the country for many years
under poor storage conditions and the government was uncertain of the
integrity of the products and their containers. There was no
in-country capacity for analysis of pesticide formulations and there
were no private-sector activities involving the manufacture,
formulation or distribution of agricultural pesticides in
Guinea-Bissau.
USAID made an inventory of obsolete pesticides in
Guinea-Bissau. In total there were just over 9 tonnes, of which 6 400
litres14. were carbaryl donated in 1988 for the locust campaign in
West Africa. The carbaryl (called Sevin 4-Oil) was formulated for
aerial application but, because the locust outbreak was more serious
in other West African countries, the spray plane and agitating pump
destined for Guinea-Bissau never arrived and the carbaryl was not
used. The carbaryl drums were stored in a secure warehouse and were
in good condition. The active ingredient of the formulation, however,
had settled and the government was unable to get the carbaryl back
into suspension. This eliminated the possibility of using the product
for other locust control uses, such as to coat grains, make baits or
use in ground equipment.
USAID recommended returning the stocks of carbaryl
to the manufacturer in the United States, who would be able to
reformulate the product if it was received before the expiry of its
shelf-life. The manufacturer had agreed to pay all costs, including
transportation, but, in spite of this no-cost option, the government
was hesitant to follow through with the return-to-sender option
because of the value of the drums. The economic reality is that a new
200-litre steel drum costs from 100 000 to 200 000 pesos (US$50 to
$100) in the local market in Bissau. Considering that a semi-skilled
worker, such as a government driver, earns about 36 000 pesos a month
(US$18), the carbaryl drums are extremely valuable. No feedback has
been received as to whether, in the end, the carbaryl was shipped out
or not.
For the relatively small quantities of pesticides
other than carbaryl, USAID recommended potentially safe alternative
uses and provided sources of additional information in this respect.
Many of the pesticides could be used to control pests where the exact
dosage rate is not critical. For example, dichlorvos could be sprayed
on the inside of walls and ceilings of mud grain storage bins to
limit pest infestation, phoxim is registered for controlling stored
product pests in granaries and for armyworm control and dicofol can
be used against the cassava green spider mite, which was identified
in 1990 as a major pest problem in Guinea-Bissau.
In 1993, the Government of El Salvador
identified significant quantities of unwanted pesticides, most of
which were in deteriorating containers, at various locations around
the country. They were concerned about the risks posed by these
unwanted pesticides and uncertain how to assess the risks and develop
appropriate mitigation options given the limited resources available
in El Salvador. Assistance from USAID was requested to conduct a
feasibility study of disposal options.
The causes of pesticide disposal problems in El
Salvador can be linked to overstocking, poor inventory control,
questionable results from formulation analysis, lost drum labels and
failing containers. Other causes of problems with pesticide disposal
are the wastes remaining after a pesticide formulating plant has
closed, poor-quality products, poor storage conditions, excessive
storage periods, lower than expected pest incidence and the banning
of product use. There was no evidence that the disposal problems in
El Salvador were caused by pesticide donations.
The aims of the pesticide disposal feasibility
study were to: assess the risks from unwanted pesticide stocks;
develop practical, cost-effective management options; provide
technical guidance on these options; provide practical facility
clean-up guidance; and train government officials in assessment
techniques.
The team conducting the feasibility study was
composed of representatives from USAID, the United States
Environmental Protection Agency (USEPA), the Government of El
Salvador and GTZ. The team visited eight storage/disposal sites
located across the country.
At two sites, 24 800 litres of malathion were
stored in containers in good condition. The malathion was purchased
in 1989 for locust control and the government was concerned about the
condition of the formulation. Subsequent analysis by GTZ verified
that the formulation was still good. Conditions at another site
appeared worse than they really were because the site was cluttered
with empty containers. At three sites, pesticides had been
buried.
The total amount of pesticides identified for
disposal was 15 tonnes, comprising: 2 400 litres of methylethyl
parathion; 800 litres of methyl parathion; 11 600 litres of liquids
with no label; and 200 litres of heptachlor.
Various disposal options were reviewed and
site-specific recommendations for pesticide disposal and storage
clean-up were presented to the government for implementation.
Although there are storage sites in El Salvador
where pesticides require disposal, the overall quantity of pesticides
identified for disposal and the risks they pose are less than in some
developing countries. Under the leadership of trained government
personnel using the proposed options, the clean-up of many
contaminated sites and the management of unwanted stocks is
technically feasible if funding is forthcoming.
The following are the lessons learnt from this
activity:
G. Vaagt, Project Leader
GTZ is operating a pesticide disposal project. Its objective is the development of concepts and proposals for the disposal of obsolete pesticides and their containers in an environmentally acceptable manner.
The main activities of the project are:
The project is a supraregional pilot project
with a time frame of 1991 to 1996.
Expertise and funds for test runs, demonstration
and training exercises will be contributed.
The main issues of the project are the promotion of preventive measures, safeguarding activities and the view of pesticide disposal as an element of pesticide management.
The following pesticide disposal operations have been completed:
Studies, assessments and proposals have been completed for:
The following activities are ongoing:
The following conclusions can be drawn:
These orientation procedures should be followed:
A video entitled Pesticide disposal Madagascar was produced by the project.
H.P. van der Wulp, Consultant
Background information was provided on the FAO
operation in 1993 to dispose of 50 000 litres of dieldrin that was
owned by the tsetse control department of Uganda and that could not
be used after its use was banned. Slides, a fact sheet, a description
of the operation and the lessons learnt were presented.
The operation was subcontracted to a United
Kingdom-based company with a dedicated hazardous waste incinerator.
The total cost was US$196 000, which included costs of a preparatory
visit and monitoring of the operations by an independent consultant
appointed by FAO.
The total input of international technical experts
was three person months, including staff provided under the
subcontract with the company (preparations required two persons in
Uganda for 10 days and one person at FAO Headquarters for one week;
field operations required two persons in Kampala for one week, four
persons in the field for one week and one person at FAO Headquarters
for one week). Overhead and administrative support at FAO
Headquarters are not included in this figure.
In summary, the scenario for the operation included
the following steps:
It took ten days for an FAO consultant and a representative of the contracted company to:
Follow-up activities involved:
Further preparation in Kampala took five days to ensure:
Travel to Fort Portal (centre of the contracting
company) took one day, repacking and on-site clean-up activities five
days and transport back to Kampala two days. It was noted that
disposal costs are likely to be higher for countries that have a
variety of products spread over a number of sites.
Furthermore, it was indicated that FAO is
investigating possibilities for disposal operations in Yemen, Zambia,
the Gambia, Senegal and Mauritania under various collaborative
arrangements. In Zambia about 60 to 80 tonnes of obsolete and
deteriorated pesticides are kept by the Zambian Cooperative
Federation (ZCF). These are stored outside, are unsecured, are
causing serious contamination and pose a threat to the Lusaka city
water supply. The problem has been recognized by government and needs
to be addressed urgently. Senegal and Mauritania have an estimated
total of 250 000 litres of dieldrin, which is stored in the open in
deteriorated drums, some of which are already leaking (see Annex 2
for a summary of disposal operations undertaken).