International Archives of Photogrammetry and Remote Sensing. Vol. XXXII Part 7C2, UNISPACE III. Vienna, 1999
114
I5PR5
V®y
UNISPACE III - ISPRS/EARSeL Workshop on
“Remote Sensing for the Detection, Monitoring
and Mitigation of Natural Disasters”
2:30-5:30 pm, 22 July 1999, VIC Room B
Vienna, Austria
EARSeL
REMOTE SENSING TECHNIQUES FOR MONITORING HAZARDOUS WASTE SITES AND SENSITIVE AQUIFERS
Vem Singhroy
Canada Centre for Remote Sensing
Ottawa, Canada
vem, singhroy@ccrs. nrcan. gc. ca
KEY WORDS: Hazardous wastes, mine tailings, hyperspectral and multispectral remote sensing, environmental restoration,
groundwater pollution.
Abstract
The deleterious effect of environmental pollution is a major international problem. Developing cost-effective techniques to monitor,
clean up and restore these polluted areas are also of major concern. In North America alone, over 100000 abandon mining sites,
containing hazardous wastes, need to be restored.
Several operational geomatic techniques are now being used for mapping polluted areas and for monitoring the clean up and
restoration activities. These techniques are also constantly being revised with the availability of higher spatial and spectral resolutions
of new remote sensing systems. In this paper, we provide examples using airborne and satellite multispectral images to monitor
restoration activities at mining sites, as well as mapping features for groundwater protection.
INTRODUCTION
The deleterious effects of hazardous waste is an international
problem. In Canada and the United States alone, over 100,000
abandoned mine sites containing hazardous wastes need to be
restored. In Central Germany also retoration of mining areas is
now a priority. In these cases, acid mine drainage from mine
waste are polluting the groundwater and are damaging nearby-
vegetation. Several remote sensing techniques have been used
to monitor the effects of hazardous wastes and environmental
pollution on land. Tins paper provides three representative case
studies to demonstrate some current remote sensing techniques.
Tire sensors used include airborne and spacebome multispectral
images, AVRIS and aerial video (Mussokowski, 1983, 1993,
Singhroy and Kruse, 1991, Repie et al 1991, King, 1993, and
Singhroy 1995, Singhroy et.al. 1989). Recently, McCubbin and
Lang 1999 applied AVIRIS data to map different mineral classes
that are associated with mine generated acid waste. Figure 1
shows general operating system for monitoring environmental
restoration in mining areas (Gleisser et. al 1999). In this paper
we provide examples on:
• the uses of multitemporal satellite and airborne hyperspectral
techniques to monitor environmental restoration caused by
sulfur dioxide fumigation and the acid mine drainage in the
Sudbury mining district in Canada.
• the use of airborne multispectral and field tecliniques to
characterize acid lakes in central Germany.
• The use of data fusion tecliniques to produce image maps for
the protection of sensitive groundwater areas in Jordan.
Monitoring Environmental Restoration, Sudbury, Canada.
This case study discusses the uses of TM and airborne
hyperspectral images from the Compact Airborne
Spectrographic Imager (casi) to monitor revegetation programs
related to mining. Multitemporal TM images were used to
monitor large areas, and casi images were used to monitor
smaller sites, where more detail information is required.
The Sudbury mining district is one of the world largest metals
smelting complexes, Canada richest mining areas and a well-
known polluted region. Mining and processing of nickel and
copper has started 100 years ago. As a result, soil and
vegetation were lost from tens of thousand of hectares of land
surrounding the smelters. The environmental damage is the
result of sulfur dioxide fumigation, and airborne deposition
from the mining smelters intense logging, wild fires, water and
wind erosion, and enhanced frost action (Winterhalder 1984).
The damaged area surrounding Sudbury is large enough to be
detected and monitored by TM images . TM images from June
1984 and 1995 were used to monitor the revegetation programs
in the damaged areas. The two TM scenes were enhanced and
then classified to measure vegetation change over the period
1984-1995. Figure 2 shows that the areas covered by mine
tailings (red areas). Over the eleven-year period, forty percent
of the damage vegetation lias been restored, because of
successful revegetation programs, combined with the reduction
of sulfur dioxide emission from the smelters. Since 1979, over 2
million trees and shrubs have been planted in a 3000 ha area of
limed soil occupied by grassland and open birch woodland
(Beckett et. al. 1995).
Figure 2 shows the use of high-resolution (3m) casi images for
site characterization and restoration of the tailings areas. The
casi images was used to monitor revegetation success and to
detect areas affected by acid mine drainage and seeps, ponding,
surface erosion and exposed and vegetated tailings. Casi is an
airborne pushbroom imaging spectrometer with sensitivity in
the visible and near infrared (430-870nm) portion of the
spectrum (Anger et al 1990, Babey and Anger, 1989). CASI
operates in both a spectral and spatial mode. In the spatial
mode, the sensor records up to 15 programmable bands, each
having a bandwidth of 1.8 nm. The spectral mode maintains full
spectral resolution of 288 bands, encompassing the entire
wavelength range of 430 to 870 nm.