{"id":2474,"date":"2017-03-24T11:30:31","date_gmt":"2017-03-24T18:30:31","guid":{"rendered":"http:\/\/www.waterandwastewatercourses.com\/?p=2474"},"modified":"2018-10-30T18:05:00","modified_gmt":"2018-10-31T01:05:00","slug":"practice-problems-wastewater-operator","status":"publish","type":"post","link":"https:\/\/www.waterandwastewatercourses.com\/practice-problems-wastewater-operator\/","title":{"rendered":"Practice Problems: Wastewater Treatment Operator Exam"},"content":{"rendered":"<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">One of the best ways to prepare for any exam is to solve many <a href=\"https:\/\/amzn.to\/2xSpGsG\">practice problems<\/a>.\u00a0 To help you study for your wastewater treatment operator certification exam, here are four practice problems.<\/span><\/p>\n<div class=\"ast-oembed-container\"><iframe title=\"Wastewater Treatment Operator Certification Exam - 4 Practice Problems\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/vVjS4bLmRpw?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/div>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">By the way, please keep in mind these problems are for anyone who is pursuing the first two certification levels.\u00a0 I included the answers at the bottom of this page. \u00a0<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">If you want more practice problems, <a href=\"http:\/\/water-and-wastewater-courses.teachable.com\/p\/wastewater-treatment-operator-certification-exam-review\">click here<\/a>.\u00a0 Or, if you want to take an online course, <a href=\"https:\/\/water-and-wastewater-courses.teachable.com\/p\/wastewater-treatment-operator-certification-exam-review\">click here.<\/a><\/span><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\"><strong>Practice Problems:<\/strong><\/span><\/h2>\n<p>&nbsp;<\/p>\n<ol>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">What is the typical removal efficiency of settleable solids in a primary clarifier?<\/span><\/li>\n<\/ol>\n<ol style=\"list-style-type: upper-alpha;\">\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">10 to 15%<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">20 to 50%<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">40 to 60%<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">95 to 99%<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">2. \u00a0Which of the following is associated with thick billows of white sudsy foam in the aeration tank?<\/span><\/p>\n<ol style=\"list-style-type: upper-alpha;\">\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Old sludge<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Low F\/M ratio<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">High F\/M ratio<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">High MLSS concentration<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">3.\u00a0 What impact does the injection of chlorine gas have on the pH of wastewater?<\/span><\/p>\n<ol style=\"list-style-type: upper-alpha;\">\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Increase pH<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Decreases pH<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Does not affect pH<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Fluctuates the pH<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">4.\u00a0 Which gas is the most abundant in a properly operating anaerobic digester?<\/span><\/p>\n<ol style=\"list-style-type: upper-alpha;\">\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Hydrogen sulfide<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Nitrogen<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Carbon dioxide<\/span><\/li>\n<li><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Methane<\/span><\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">If you&#8217;re preparing for the operator certification exam, check out our latest<a href=\"http:\/\/water-and-wastewater-courses.teachable.com\/p\/wastewater-treatment-operator-certification-exam-review\"> online course that covers 90 practice problems.<\/a><\/span><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\"><strong>Answers:<\/strong><\/span><\/h2>\n<ol>\n<li>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">D<\/span><\/h2>\n<\/li>\n<\/ol>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">The typical removal efficiency for settleable solids in a primary clarifier is 95 to 99%.\u00a0 Make sure to memorize the removal efficiency for other constituents, such as suspended solids and BOD.\u00a0 Questions on removal efficiency are fairly common on the operator exam, so study them.\u00a0 Typically, they\u2019ll expect you to memorize the removal efficiencies.\u00a0 You may want to create flash cards to memorize these numbers.\u00a0 There\u2019s not much to these questions except memorization.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">For more information on removal efficiencies of the primary clarifier, read page 129 of the textbook, <em>Operation of Wastewater Treatment Plants , Volume 1, 7th Edition.<\/em><\/span><\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">2.\u00a0 C<\/span><\/h2>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Thick billows of white sudsy foam in the aeration tank is often encountered during the start-up of a treatment plant.\u00a0 In this stage, there aren\u2019t many microorganisms in the aeration tank, but there\u2019s plenty of food (BOD) coming in.\u00a0 When you calculate the F\/M ratio, you\u2019ll get a larger number because the \u201cF\u201d or food is a big number, while the \u201cM\u201d or microorganism population is fairly small.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Another characteristic that\u2019s associated with thick billows of white sudsy foam in the aeration tank is young sludge, which is a group of microorganisms that hasn&#8217;t spent a lot of time in the aeration tank.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">This is also a fairly popular question on certification exams.\u00a0 Remember that thick billows of white sudsy foam in the aeration tank is associated with a high F\/M ratio and young sludge.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">For more information, go to pages 53 and 75 of the textbook, <em>Operation of Wastewater Treatment Plants, Volume 2, 7th Edition.<\/em><\/span><\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">3.\u00a0 B<\/span><\/h2>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">When chlorine gas is added to wastewater, it decreases the pH because it forms acids when it is mixed with wastewater.\u00a0 Whenever acids are formed in liquid, they will lower the pH, since acids have low pH.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Make sure you understand the pH scale before you take the exam.\u00a0 You won\u2019t be able to answer this type of question correctly without understanding the basics of the pH scale.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">If you want to learn more about the impacts of chlorine gas to wastewater, read pages 349 and 350 of the textbook, <em>Operation of Wastewater Treatment Plants, Volume 1, 7th Edition.<\/em><\/span><\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">4. \u00a0 D<\/span><\/h2>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Methane is the most abundant gas in an anaerobic digester.\u00a0 It accounts for about 65 to 70% of the digester gas.\u00a0 The second most abundant gas is carbon dioxide, which accounts for about 30 to 35%.\u00a0 Lastly, there\u2019s a very small amount of hydrogen, nitrogen, and hydrogen sulfide, which account for a combined 1 to 2% (hydrogen + nitrogen + hydrogen sulfide).<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Questions on the composition of digester gas is also common on the exam.\u00a0 You\u2019ll have to memorize the percent composition of each gas in the digester.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">If you want to learn more about the composition of digester gas, read page 158 of the textbook, <em>Operation of Wastewater Treatment Plants, Volume 2, 7th Edition.<\/em><\/span><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<h2><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\"><strong>Helpful Resources<\/strong><\/span><\/h2>\n<p>&nbsp;<\/p>\n<p><a href=\"https:\/\/amzn.to\/2JyMtyk\"><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Practice Exams<\/span><\/a><\/p>\n<p><a href=\"https:\/\/water-and-wastewater-courses.teachable.com\/p\/wastewater-treatment-operator-certification-exam-review\"><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">Online Course<\/span><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif; font-size: 14pt;\">If you&#8217;re looking for additional practice problems, <a href=\"https:\/\/www.waterandwastewatercourses.com\/practice-problems\/\">click here.<\/a><\/span><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>One of the best ways to prepare for any exam is to solve many practice problems.\u00a0 To help you study for your wastewater treatment operator certification exam, here are four practice problems. By the way, please keep in mind these problems are for anyone who is pursuing the first two certification levels.\u00a0 I included the &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"ast-button\" href=\"https:\/\/www.waterandwastewatercourses.com\/practice-problems-wastewater-operator\/\"> <span class=\"screen-reader-text\">Practice Problems: Wastewater Treatment Operator Exam<\/span> Read More \u00bb<\/a><\/p>\n","protected":false},"author":1,"featured_media":2488,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[94],"tags":[108],"class_list":["post-2474","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-wastewater-math-practice-problems","tag-practice-problems-for-wastewater-treatment-operator-certification-exam"],"jetpack_featured_media_url":"https:\/\/www.waterandwastewatercourses.com\/wp-content\/uploads\/2017\/03\/Broken-Arrow-WWTP-4.jpg","_links":{"self":[{"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/posts\/2474","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/comments?post=2474"}],"version-history":[{"count":11,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/posts\/2474\/revisions"}],"predecessor-version":[{"id":2482,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/posts\/2474\/revisions\/2482"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/media\/2488"}],"wp:attachment":[{"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/media?parent=2474"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/categories?post=2474"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.waterandwastewatercourses.com\/wp-json\/wp\/v2\/tags?post=2474"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}