356B review exams

 

 

1. Air Pollution

The criteria pollutants are as follows: SOx, NOx, CO, particulates, lead, hydrocarbons, and ozone.

Ozone is considered as a secondary pollutant.

Inversion is defined as temperature increases with altitude.

 

Carbon monoxide is colorless, tasteless, and odorless. Symptoms of carbon monoxide poisoning are headache, poor reflexes, drowsiness, and death at 750 ppm. Carbon monoxide is an asphyxiant that has a greater affinity for red blood cells than oxygen at a rate of 200 to 1.

 

The size of particulate is crucial in health effects, at less than 3 microns the greatest problems occur. Usually at greater than 10 microns there is no penetration.

The lower respiratory tract has no cilia or mucus for defense, it uses macrophage to attack the foreign invader. This is also dependent on the person’s age, health status, and other variables.

 

Plants are effected by SOx, NOx, and ozone, which suppress photosynthesis. Necrosis is when tissue is killed, chlorosis is color changes i.e. (bleaching) etc. Some plants are more sensitive than others making them good indicators of potential problems.

 

Acid rain is commonly associated with the northeast U.S, and Germany. Sox, as well as NOx can result in environmental problems from a change in metabolism of different animals to corrosion of fabrics resulting in millions of dollars in damage.

 

The bag house filter is 99.9% efficient. When properly maintained it is among the best technological controls. Some problems may occur if not properly maintained.

 

EPA reference method for detecting SOx is Para rosaniline.

EPA reference method for detecting NOx is Chemiluminescence.

Non dispersive infrared analysis is used for detecting carbon monoxide.

 

Particulates are solid and liquid aerosols that are suspended in air.

Dusts are solids from various physical processes (>1 micron)

Smokes are solids from incomplete combustion (< 1 micron)

Fumes are solids from vapor condensation. (< 1 micron)

Mists are liquids from vapor condensation. (< 10 micron)

Sprays are liquids from atomization of a parent liquid. (> 10 micron)

 

 

2. Water Quality

 

Zone of aeration (vadose zone) is the porous area without freestanding water.

Zone of saturation (aquifer) is the underground layer of sand, gravel, or porous rock that is saturated with water.

Confined aquifer is the well located below solid rock formations.

Water table (phreatic surface) is the top of the zone of saturation.

Effective porosity (specific yield) is the % of total volume of water that drains freely from aquifer.

 

Oligotrophic = young lake

Mesotrophic = middle aged lake

Eutrophic = old or mature lake

 

Epilimnion = top layer of lake

Metalimnion = middle layer of lake

Thermocline = located within metalimnion, has the largest temperature change.

Hypolimnion = bottom layer of the lake

 

 

 

Cross Connections

Cross connection is any physical connection between wastewater and potable water that may cause the non-portable water to contaminate the portable water.

 

Backflow is a force that pushes the wastewater towards potable water.

Backsiphonage is the backflow caused by atmospheric pressure against a vacuum. (- psig)

Backpressure is the backflow caused by differential pressures that are greater than atmospheric pressure. (+ psig)

 

 

 

 

3. Swimming Pools

 

The ideal recirculation of water (turn over rate) for swimming pools is once every 6 hours, or 4 times per day.

(Once every ½ hour for spas.)

 

Cyanuric acid is a stabilizer, it is added to the pool to prevent the excessive dissipation of chlorine from the sunlight.

 

Free chlorine residual should be maintained at 1 ppm. (or 1.5 ppm if cyanuric acid is added to pool.)

 

Free residual chlorine (HOCL + OCI) occurs after breakpoint.

Combined chlorine (chloramine) occurs before breakpoint.

 

To raise the pH of swimming pools, add soda ash or sodium carbonate.

To lower the pH of swimming pools, add muriatic acid.

 

HOCL = Hypochlorous Acid (a stronger disinfectant)

OCL- = Hypochlorite Ion (a weak disinfectant)

 

 

 

 

4. Wastewater

 

Organic pollution

BOD (Biochemical Oxygen Demand) – to measure dissolved oxygen used by micro-organism in the biochemical oxidation of organic matter.

Also used to determine the strength or potency of the sewage.

COD (Chemical Oxygen Demand) – to measure dissolved oxygen used by an oxidizing agent in the oxidation of organic matter.

TOD (Total Oxygen Demand) – for measuring oxygen before and after.

TOC (Total Organic Carbon) – measure the conversion of CO2 from organic carbon.

 

There is no common indicator to measure inorganic pollution.

 

There are 5 types of wastewater sources:-

Domestic waste

Industrial waste

Ground water

Storm drain runoff

Municipal waste

 

Black water is wastewater that comes from latrine and water closets.

Grey water is wastewater that comes from laundry and kitchen sinks.

 

Septic tanks are domestic treatment of the sewage on a property. Sewage is discharge into a tank, the wastewater is retained for about 24 hours. Sludge is collected at the bottom of the tank where anaerobic bacteria will digest the nutrient and helps destroy the pathogenic organism.

 

 

5. Wastewater Treatment

 

Primary treatment: removes solids that can settle

Sedimentation

 

Secondary treatment: collect raw sludge and locate to another treatment site for sludge digestion.

Biological

Chemical

Physical

 

Tertiary treatment: further use of filters to removes particles, color and odor. And destroy pathogenic bacteria.

Filtration

Disinfection

 

Primary wastewater treatment includes sedimentation basin and imhoff tank.

Secondary wastewater treatment includes trickling filter and rotating biological contactor.

Tertiary wastewater treatment includes electrodialysis.

 

Zooglea microbes are used on the rocks of trickling filter to digest sludge.

 

PERC test is a test performs to check the absorption factor of water of a place to determine the porosity of the soil. A hole a dug, the diameter of the hole is between 4 to 12 inches. The depth is between 2 to 3 feet. Water is then placed in the hole for a period of not less than 24 hours to properly saturate the test hole for the PERC testing.

 

 

6. Radiation

 

Ionizing radiation includes: -

Alpha

Beta

Gamma Ray

X-rays

 

Non-ionizing radiation includes: -

Microwave

Ultra-violet (U.V.) light

Infrared light

Laser

 

Radioactive half life is the time for a material to lose half its radioactivity.

 

Biological half life is the time for living tissue to eliminate through biological processes ½ of a given amount of substance.