AIR The Clean Air Act and Controlling Air

AIR The Clean Air Act and Controlling Air Pollution

History of Legislation • Original CAA of 1955 predates the EPA by 15 years • It authorized technical and financial assistance to states • Amendments were made in the 60’s, in 1970, 1977, and most recently in 1990

1960’s Amendments • Amendments in the 60’s granted federal authority over vehicle emissions • In 1970 requirements for national standards of ambient air quality were established NAAQS – w/ separate standards for new cars & stationary sources

1970 Amendments • In 1970 air toxics were added as a new category of pollutants not covered under the original standards • The National Emissions Standards for Hazardous Air Pollutants or NESHAP • Substances included arsenic, asbestos, benzene, beryllium, mercury, radionuclides, radon 222, and vinyl chloride

State Requirements – 1970, Title I • States were required to draw up state implementation plans – SIPs • SIPs or State Implementation Plans are a collection of regulations a state will put into place to achieve the goals of the CAA • These detail how ambient air standards would be met in each “air quality control region”

• The plan must include an inventory of all present sources and operating standards for all new development • The EPA oversees the individual states’ plans and will take over enforcement if the state’s plan is unacceptable

1977 & 1990 Amendments • The 1977 amendment stated that new facilities could be built in an area that was not meeting standards if existing sources could reduce their pollution • The original act was just 50 pages long • The 1990 amendments are close to 800 pages!

• The 1990 amendments addressed new issues such as acid rain emissions and moves to preserve the stratospheric ozone layer • It established a system of tradable emission credits

Criteria Air Pollutants • Primary standards – maximum ambient concentrations for the protection of the public health • Secondary standards – levels acceptable to protect the public welfare

Nonattainment • Not meeting the EPA’s primary standards • 90 million Americans, 35% of the population live in nonattainment areas (mostly in urban areas)

Levels of Nonattainment • Range from marginal to extreme • Set for each of the criteria air pollutants • The EPA tailors cleanup plans to the severity of the problem and sets goals that must be met or even stricter requirements will be enforced

Offsets • When a company wants to expand • The effect of new pollution sources must be offset by reductions elsewhere within the company or somewhere in the nonattainment area

Title II Mobile Sources • Cars produce 60 -80% less pollution than they did in the 1960’s • However, automobiles still release over half of the smog-forming VOC’s and nitrogen oxides • Motor vehicles emit 90% of the CO found in urban air

More Cars on the Road • In 1970 Americans traveled 1 trillion miles • Today we drive 4 trillion miles a year • Public transportation and car pooling have not been embraced by the general population

• Removing lead from gasoline actually increased the amount of VOC’s released • Pollution control devices, added to cars in 1970, were only designed to function for 50, 000 miles

New Solutions in 1990 • • Cleaner fuels Auto inspection requirements Removing sulfur from diesel fuel Reformulated fuels with less VOC’s such as benzene • Oxygenated fuels in cold areas to aid in more complete combustion

• Detergents in gasoline prevents build-up of engine deposits which hamper efficient operation • Development of alternative fuel sources such as alcohol, liquefied petroleum gas and natural gas • Vapor recovery nozzles at gas stations

Title III Air toxics or hazardous pollutants • Benzene is released by motor vehicles • Area emitter - Many small stationary sources include gas stations, paint shops and dry cleaners • Major emitter - Chemical factories and coalburning power plants are considered large stationary sources

Title IV Acid Rain • Coal burning power plants in the Midwest and the Northeast are the primary source • Coal from these regions has a much higher sulfur content • Under Title IV, plants must have continuous emissions monitoring systems

• A system of emission allowances has been imposed • These allowances can be traded or sold nationwide • Bonus allowances are given to companies installing clean coal technology or using renewable energy sources

Title V Permit Program • Permits are required by all major sources of air pollution and some smaller polluters, both for operating plants & new plants • They include information on the type of pollutants emitted, how they’re controlled and how they will be monitored • The EPA has the authority to fine violators

Title VI Stratospheric Ozone • 1978 – propellants in aerosol can were banned • 1990 – schedule set for the phasing out of ozone-destroying chemicals • The EPA has issued allowances for these substances in the mean time

• Recycling and labeling of these materials is required • Service and maintenance of car air conditioners is strictly regulated • New substitute products are being tested before being put into use

Title VII • Covers enforcement provisions

Title VIII - IX • • Miscellaneous topics Greenhouse gases International issues Disadvantaged business concerns

End Legislation/Begin Sampling & Remediation Techniques

Sampling and Analysis of Emissions • Ambient monitoring data allows us to see trends in air quality over time • Provides baseline information • Helps in developing computer models • Help predict potential episodes

• Source emissions data is used to evaluate compliance • Determines whether equipment is efficient and effective • Hazardous pollutants are monitored at their source under the provisions of the NESHAPs standards

Monitoring Process • Two parts – sampling and data management • Sampling methods depend on the pollutant, its physical state and its expected concentration • Concentrations are measured in mass per unit volume, usually micrograms per cubic meter or ug/m 3

Calibration • Checking and adjusting of instruments to insure quality control • Comparing readings with a known standard

Quality Assurance • Specific guidelines for analysis, calibration and calculation are listed as appendices of CFR 40 Part 50 • The EPA publishes a three volume Quality Assurance Handbook • Agencies are required to provide a daily air quality index report in all urban areas with at least 500, 000 people

The Gravimetric Approach • Manual method used to measure particulate matter • High volume method - catches material in a filter as it is drawn in by a blower • The filter is weighed before and after

• Lead is collected in a similar fashion • But must be separated from other particulates by dissolving it from the other particulates using acid • The lead content of the solution is determined using an atomic absorption spectrometer

Carbon Monoxide Measurement • An automated method involving a infrared spectrometric principle • CO absorbs infrared radiation at characteristic wavelengths

• A sealed reference cell is compared to a sample cell through which the air passes • When CO is present, it absorbs the radiation and the change is detected electronically

Ozone • An automated method which involves gas phase chemiluminescence, chemical reactions that produce light • Air is drawn through a tube containing ethylene which reacts with ozone emitting light that can be detected by a photomultiplier tube

Nitrogen oxide • Detected in the same way as ozone • But a different gas, ozone is used to create the reaction

Where Samples are Taken • Is not specified in the Federal Reference Methods • Downwind – upwind • Proximity to trees, buildings and roadways

New Sources • Where construction begins after the EPA publishes standards in the Federal Register • The New Source Performance Standards, or NSPS, apply to specific sources • The type of pollutants to be monitored, the allowable concentrations, kinds of monitoring required and the reference method used

Isokinetic Sampling • Velocity of the gas at the sampling probe nozzle is the same as the velocity of the gas stream in the stack

Grab Technique • Measures the volume of a sample by taking it at only one location, during one short continuous period of time

Integrated Sampling • Takes samples from different locations over an extended period of time that is not necessarily continuous

Continuous Sampling • Measuring a sample continuously using a source emission monitor

Air Pollution Control Techniques • Equipment, processes or actions to reduce air pollution • In serious nonattainment areas the Best Available Control Technology, BACT, will be required • The Maximum Achievable Control Technologies, MACT, are required for sources emitting hazardous pollutants

Process Change • • Changing to low sulfur fuel Reformulated gasoline Alternative energy sources Housekeeping and maintenance

Emission Allowances • An allowance is the limited authorization to emit one ton of SO 2 • They can be traded or banked for future use • Traded on the Chicago Board of Trade

• They are not a license to violate federal or state standards • Companies without sufficient allowances are fined $2000 per ton for their excess emissions and will lose one allowance for each during the next year • The bubble policy allow sources to be grouped to determine compliance

Control Equipment for Gaseous Emissions • • Adsorption Absorption Condensation Combustion

Adsorption • Allowing the pollutant molecules to become attached to a solid surface like activated charcoal • Can be regenerative or non-regenerative

Absorption • Dissolving of a gaseous pollutant in a liquid solvent • Spray towers, spray chambers, Venturi scrubbers and packed columns all maximize the opportunity for gas-liquid mixing

Condensation • Gas or vapor is changed into a liquid by cooling or an increase in pressure • Temperature reduction is the most cost effective

Combustion • Combining a combustible material with oxygen producing heat and light • Equipment includes flares, thermal incinerators and catalytic incinerators

Removing Particulates • Efficiency of devices is calculated by taking the difference in the weight of particles in the air before and after, divided by the weight of particles when entering • Control devices include settling chambers, cyclones, wet scrubbers, electrostatic precipitators, and fabric filters installed in a bag-house