Technology-based standard (tbs)—is an effluent standard set at the level of emissions that a source would produce if it were employing a particular type of abatement technology.
For example, the regulator is concerned about vegetable processing plants. This is a process that uses a large amount of water for cleaning and processing purposes; thus, the wastewater may contain large amounts of suspended solids and BOD.
to be socially efficient, the standard must be set where MAC = MD for a given pollutant and its source.
unlikely that MDs are identical across the province or the country, and even more unlikely that MACs are identical for all pollution sources
Cost-efficiency
A totally technology-based approach to pollution control thus cannot in practice be either cost effective of socially efficient.
Cost-effectiveness examines whether we are getting the maximum effect, in terms of reduced emissions, for the money spent.
A policy will be cost-effective if it is designed so that when sources are in compliance they will have the same marginal abatement costs.
TBS
A TBS will be cost-effective only if all individual plants in each category have exactly the same marginal abatement costs\
There are thousands of individual industrial water-pollution sources, so some of the subcategories must contain very large numbers of sources.
Applying the same emission standards to each firm cannot be cost-effective.
Nonpoint-Source Emissions
BOD, suspended solids, phosphorus, and nitrogen come from nonpoint sources.
The fact that NPS emissions are diffuse and not concentrated into specific outfalls has made them very difficult to control. NPS pollutants are also normally very weather-related, which makes the runoff patterns more difficult to monitor.
