Page 18 - Environmental Control in Petroleum Engineering

Introduction to Environmental Control in the Petroleum Industry 7

1.1.3 Waste Migration

In most cases, the environmental impact of released wastes would
be minimal if the wastes stayed at the point of release; unfortunately,
most wastes migrate from their release points to affect a wider area.
The migration pathway most often moves through groundwater along
the local hydraulic gradient. For releases at sea, wastes will follow
the prevailing winds and currents. For air emissions, the pollutants will
follow the winds. Because migration spreads the wastes over a wider
area, the local concentrations and toxicities at any location will be
reduced by dilution.

1.1.4 Managing Wastes

The most effective way to minimize environmental impact from
drilling and production activities is to develop and implement an
effective waste management plan. Waste management plans identify
the materials and wastes at a particular site and list the best way to
manage, treat, and dispose of those wastes (Stilwell, 1991; American
Petroleum Institute, 1989). A waste management plan should also
include an environmental audit to determine whether existing activities
are in compliance with relevant regulations (Guckian et al., 1993),
The effective management of each waste consists of a hierarchy of
preferred steps. The first and usually most important step is to mini-
mize the amount and/or toxicity of the waste that must be handled.
This is done by maintaining careful control on chemical inventories,
changing operations to minimize losses and leaks, modifying or
replacing equipment to generate less waste, and changing the processes
used to reduce or eliminate the generation of toxic wastes.
The next step in effective waste management is to reuse or recycle
wastes. If wastes contain valuable components, those components can
be segregated or separated from the remainder of the waste stream and
recovered for use. Wastes that cannot be reused or recycled must then
be treated and disposed of. A written waste management plan that
completely describes the acceptable options for handling every waste
generated at every site must be developed and effectively communi-
cated to every employee involved with the wastes. Examples of how
the waste management hierarchy can be implemented are given by
Thurber (1992), Derkies and Souders (1993), and Savage (1993).