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NEW! What is cap rock?
Answer: Cap rock is the layer of very dense rock above reservoir rock and source rock that keeps underground natural gas from traveling to the surface. For more on this, see the “Older Than Dinosaurs” section in our Natural Gas Safety-SMART module on this site: http://www.e-smartonline.net/dom/66400_get_smart/ngas_safety-smart/66721_natural_gas_science/dinosaurs.html.
NEW! I stood next to two large green boxes, transformers I assume, for about 20 seconds. In that time I felt a tingle/mild heat through my body. What’s that all about, and did it hurt me?
Answer: Safety is our number one core value. We build and maintain our equipment to ensure that we provide safe and reliable electric service for our customers. Any time you have a safety concern, such as the green boxes you mentioned, please move safely away and call Dominion. We will investigate your concern to determine whether or not the boxes are our equipment, and take any corrective actions that may be needed. Even if the green boxes are not ours, we will ensure that the owner of the equipment is notified and your concern is appropriately addressed.
Should liquefied natural gas be exported?
Answer: Our nation has vast reserves of natural gas, enough to easily meet domestic needs and have enough for limited sales overseas. Along with being part of the president’s plan to help the world shift to cleaner fuels, exporting liquefied natural gas will create thousands of jobs and provide a major boost to our economy.
At what depth are residential power lines normally buried?
Answer: Underground power lines in the Dominion service area are buried at depths specified by the National Electrical Safety Code. In general, buried power lines carrying up to 600 volts must be buried at least 24 inches deep, and lines carrying between 601 and 50,000 volts must be at least 30 inches deep, although there are variations on this rule. Landscaping or excavation work in the area can change ground conditions after a power line has been installed and alter its depth. If your family is considering a digging project, always call Miss Utility at 811 to have utilities marked before digging, to allow time for all the utilities to be marked, and to obtain a positive response from Miss Utility.
Is it possible to have an underground power line? How much does an underground power line cost?
Answer: Yes, underground power lines are indeed possible, and are in place all over the country. But putting power lines underground is very expensive. The cost varies according to the type of the line and the geographic location, so I can't provide an exact dollar amount.
How can lightning kill you?
Answer: A lightning strike can carry up to 100 million electrical volts. That's as much electricity as is contained in about 8 million car batteries. A shock of this size can disrupt the body's electrical signals, and stop the heart and brain. For tips on how to stay safe in a lightning storm, check out our site's lightning safety section here: http://www.e-smartonline.net/dom/66400_get_smart/elec_safety-smart/66431_case_of_emergency/lightning.html
Someone told us we could get electrocuted playing on a green power box. Is that true?
Answer: Those green power boxes are called transformers, and their function is to reduce the high voltage of the electricity that travels from power plants along distribution wires so that it can then travel safely along service wires to homes and businesses. Transformers contain equipment that is very dangerous to touch. That's why they have warning signs on them. You could get electrocuted by touching the equipment inside them. This is why you should tell an adult if you ever see one that is damaged or unlocked. As a rule, it's much safer to play far away from them.
Is there a law or regulation as to how high a Dominion power line must be above the ground?
Answer: There are some strict national guidelines stating required heights for overhead power lines above streets, sidewalks, alleys, roads, properties, and driveways. The National Electrical Code (NEC) is the organization that determines acceptable clearances for power lines to keep people from contacting them.
How does natural gas form?
Answer: Natural gas is formed very slowly, deep inside the earth. Over millions of years tiny plants and animals that have died and decayed are buried by mud, sand, and silt, and the forces of heat and pressure inside the earth turn them into natural gas. Certain types of rock formations underground allow the natural gas to form and collect.
Why does metal electrocute you?
Answer: Metal itself cannot electrocute you. However, metal is a good conductor of electricity, which means it allows electricity to flow easily through it. Electricity is a form of energy carried by moving electrons, which are particles that orbit the center of an atom. The electrons in the atoms of metals are only loosely attached, so electricity can travel through them easily. That's why, in order to protect yourself from electric shock, it's so important to never put a metal fork in a toaster, to stay away from metal fences and poles during a lightning storm, and to keep metal ladders away from power lines.