639
Symposium on Remote Sensing for Resources Development and Environmental Management / Enschede / August 1986
Remote sensing assessment of environmental impacts
caused by phosphat industry destructive influence
S.C.Mularz
University of Mining and Metallurgy, Poland
ABSTRACT: A number of remote sensing techniques, such as colour aerial photography, black
and white aerial photography and thermal imaging have been used to detect adverse environ
mental impacts associated with the location of the phosphogypsum dump area. As an effect
of processing and interpreting remotly sensed data, assessments of water pollution, solid
waste disposal impacts on toe-failure deformations zones and the degree of vegetation co
ver damages, have been specified. Results of experiments indicate that remote sensing me
thods are an irreplaceable tool to solve environmental monitoring, as well as planning
problems. Wide-area repetitive coverage by remote sensors provides information which is
not readily available by conventional measuring techniques.
1 INTRODUCTION
In a wet-process of phosphoric acid produ
ction from apatite and phosphorite, phos
phogypsum is generated as the major by-pro
duct. In such technology large quantities
of waste are produced(as a rule, 5-5 tons
of phosphogypsum are produced for each ton
of phosphoric acid produced).
Phosphogypsum is composed mainly of gyp
sum (CaSG^. 211^0 ) , which makes 93-95$ of
total waste mass. The remaining 5-7$ is com
posed od different admixtures like: noncom-
bined molecules of phosphoric acid and phos
phates (together 0.4 - 1.5$ of P^O ) * sili
ceous acid, fluorine compounds, organic mat
ter and also some radioactive substances.
Phosphogypsum is very burdensome substance
to the natural environment, and causes its
degradation because of harmful contamina
tion. Therefore, it is necessary to study
and to monitor environmental changes occur-
ing in phosphogypsum dumping areas.
Remote sensing techniques are very useful
for this purpose, as they make it possible
to record the complex data, which is nece
ssary for a thourough interpretation of na
tural conditions. They also make a qualita
tive and quantitative analysis of phenome-
nas and processes that happen on dumping
and adjacent regions, possible.
The results of investigations, based on
remote sensing techniques, of a phospho
gypsum dumping area of a chemical factory,
near Szczecin, are presented in the paper.
Presently, 3-5 million tons of waste are
acumullated here annually, which accounts
for 70$ of the phosphogypsum generated in
Poland.
The main purpose of the investigation was
to asses the usefulness of remote sensing
techniques for:
- the creation of a complex environmental
monitoring system for the dumping area,
- periodically mapping the progress in
dumping operations,
- the assessement of the hazard for st^ff,
heaping machines and constructions, which
are located close to the dump area.
The objective of the research reported here
was to also examine the environmental dama
ges in the dump influence zone.
2 STUDY AREA, PROBLEM DEFINITION AND DATA
Geographically, the dumping area is loca
ted near the Odra river estuary, north of
Szczecin ( Figure 1).
25 km
■ - —»
Figure 1. Location of the study area on
Landsat MSS ( Band 4) image portion.
Morphologically,it lays on the flooding
terrace of the Odra river. Originally the
terrain was flat, with an average height of
1 m below sea level. Considering the geolo
gical conditions, it was found that the dump
subgrade is composed of holocene deposits,
which are organic in the upper part (peats,
organic outwashes) and, in the lower part,
consist of sand and gravel layers. They are
underlaid by older pleistocene clays, some
times interbeded with sands. The holocene
deposits are 8-11 meters thick, locally up
to 15 meters. The pleistocene deposits are
several tenths of a meter in thickness.
From a geotechnical point of view the up
per organic layer is very weak, practically
unstable, easy to defOrmate under loading.
This feature of the base was confirmed by
toe-failure which occurs on a large scale
during the dump formation. As a result of