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Worksheet Grade 10 English Language Arts

The Ormerod Membrane Cleaning Procedure: A Close Reading

A grade 10 worksheet on following a complex multistep procedure, with thirteen items on sequence, exceptions, and the difference between shall and may.

Objectives

  1. Students will restate the stated purpose and scope of a technical procedure.
  2. Students will identify the exceptions a procedure defines and the steps they attach to.
  3. Students will explain the difference in obligation between shall and may in a procedure.
  4. Students will name what a shortened summary of a procedure leaves out.

Vocabulary

Key words: procedure, scope, exception, obligation, sequence, differential pressure, permeate

Teacher overview

Technical procedures are read differently from other informational texts, because a reader who skips a conditional sentence gets a different result rather than a weaker interpretation. This worksheet uses a cleaning procedure for a reverse osmosis train, a bank of membranes that water is forced through under pressure and that clog over time. The misconception to name first is that a procedure can be read as a list of actions with the conditions treated as background. Students reliably notice the timer in a step and miss the sentence that changes the timer, which is exactly the error item 4 sets up.

The Ormerod Membrane Cleaning Procedure: A Close Reading — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

The Ormerod Regional Water Treatment Plant and the procedure below are fictional, written for this worksheet. Read the procedure, then answer questions 1 through 13.

Ormerod Regional Water Treatment Plant, Standard Operating Procedure 12: Membrane Clean-In-Place

Purpose and scope. This procedure describes the clean-in-place sequence for a single reverse osmosis train. It applies to trains A, B, and C. It does not apply to the cartridge prefilters, which are replaced rather than cleaned.

Preparation

Step 1. Notify the shift supervisor. Record the train number, the date, the differential pressure across the train, and the permeate conductivity before the train is removed from service.

Step 2. Close the feed valve and open the drain valve on the train being cleaned. Confirm that the other two trains remain in service.

Step 3. Verify that the cleaning tank is empty and that the tank heater is off. Record the check on the log sheet.

Alkaline wash

Step 4. Mix the alkaline cleaning solution in the cleaning tank according to the label on the container. Do not mix the solution until Step 3 has been completed and recorded.

Step 5. Measure the pH of the mixed solution. The pH shall be between 11.5 and 12.0. If the reading falls outside that range, adjust the solution and measure again before starting the pump.

Step 6. Start the cleaning pump and recirculate for 45 minutes. If the feed temperature is below 68 degrees Fahrenheit, recirculate for 90 minutes instead.

Step 7. Watch the differential pressure during recirculation. If it rises above 45 psi at any point, stop the pump and notify the shift supervisor before continuing.

Rinse

Step 8. Drain the cleaning tank to the neutralization basin. The solution shall not be sent to the storm drain.

Step 9. Rinse with permeate until the conductivity of the rinse water returns to within ten percent of the value recorded in Step 1.

Step 10. An operator may shorten the rinse only with the shift supervisor's approval, recorded in the log.

Return to service

Step 11. Open the feed valve slowly, then close the drain valve.

Step 12. Record the differential pressure after cleaning and compare it with the value recorded in Step 1.

Step 13. If the differential pressure has not dropped by at least twenty percent, notify the shift supervisor and do not return the train to full flow.

Questions

  1. In one sentence, state the purpose of this procedure using the document's own wording.
  2. Name the four stages of the procedure in the order the document gives them.
  3. Quote the sentence that tells an operator what to do when the pH of the mixed solution reads outside the stated range.
  4. A trainee sets the recirculation timer for 45 minutes. The feed temperature reads 61 degrees Fahrenheit. What does the procedure require instead?
  5. Explain how a reader who skimmed Step 6 could make the trainee's mistake in item 4.
  6. Name the two steps that require an operator to stop or hold the train and notify the shift supervisor.
  7. Which step must be completed and recorded before the cleaning solution is mixed?
  8. A summary of the procedure reads: "Mix the solution, recirculate for 45 minutes, rinse, and return the train to service." Name two conditions this summary leaves out.
  9. Step 8 uses "shall" and Step 10 uses "may." Explain the difference in obligation those two words create for the operator.
  10. Put these four actions in the order the procedure requires:
    • Open the feed valve slowly
    • Record the differential pressure before the train is removed from service
    • Drain the cleaning tank to the neutralization basin
    • Measure the pH of the mixed solution
  11. Explain why the procedure requires the differential pressure to be recorded both before and after cleaning rather than only after.
  12. Rewrite Step 6 as one sentence a new operator could follow, without losing the exception it contains.
  13. Name the one thing this procedure states it does not cover.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: The procedure describes the clean-in-place sequence for a single reverse osmosis train. Credit any restatement drawn from the purpose and scope paragraph; do not credit answers that describe what cleaning accomplishes, since the document does not say.
  2. Answer: Preparation, alkaline wash, rinse, return to service. All four in that order are required for full credit.
  3. Answer: "If the reading falls outside that range, adjust the solution and measure again before starting the pump."
  4. Answer: Ninety minutes of recirculation. Step 6 sets 45 minutes as the ordinary time but requires 90 minutes whenever the feed temperature is below 68 degrees, and 61 degrees is below that threshold.
  5. Answer: The first sentence of Step 6 is a complete instruction on its own, so a reader who stops there has an action and a number and no reason to keep reading. The exception arrives in a second sentence that begins with a condition rather than a verb, which is easy to treat as background rather than as part of the instruction.
  6. Answer: Step 7 and Step 13. Step 7 requires stopping the pump when the differential pressure rises above 45 psi, and Step 13 requires holding the train off full flow when the pressure has not dropped by at least twenty percent after cleaning.
  7. Answer: Step 3, the check that the cleaning tank is empty and the heater is off. Step 4 states directly that the solution is not to be mixed until Step 3 is completed and recorded.
  8. Answer: Accept any two of these: the temperature exception that changes 45 minutes to 90; the pH range and the requirement to remeasure before starting the pump; the pressure limit in Step 7; the requirement that the spent solution go to the neutralization basin and not the storm drain; the conductivity endpoint for the rinse; and the twenty percent pressure check before full flow.
  9. Answer: "Shall" states a requirement with no discretion, so sending the spent solution to the storm drain is prohibited in every case. "May" grants a permission that the operator can use or not, and Step 10 narrows it further by attaching a condition, since the shortened rinse is allowed only with supervisor approval recorded in the log.
  10. Answer: Record the differential pressure before the train is removed from service; measure the pH of the mixed solution; drain the cleaning tank to the neutralization basin; open the feed valve slowly. This follows Steps 1, 5, 8, and 11.
  11. Answer: The before reading is the only baseline available, and Step 13 asks whether the pressure dropped by a stated share rather than whether it reached a stated value. Without the first reading there is nothing to compare the second one against, so the operator cannot tell whether the cleaning worked.
  12. Answer: Accept any single sentence that keeps both the ordinary time and the exception, such as: "Start the cleaning pump and recirculate for 45 minutes, or for 90 minutes if the feed temperature is below 68 degrees Fahrenheit." Do not credit rewrites that drop the temperature condition or that turn it into advice rather than a requirement.
  13. Answer: The cartridge prefilters, which the scope paragraph says are replaced rather than cleaned.

Differentiation

Support

Give these students a copy of the procedure with every conditional sentence printed in a second color, so the exceptions are visible before the questions begin. Provide a four-box strip for item 10 to sequence physically, and allow items 5 and 11 to be answered in two sentences using the frame "A reader could miss ___ because ___."

Extension

Ask these students to write the two log-sheet entries the procedure implies but never shows: one for a cleaning that went as written, and one for a cleaning stopped partway under Step 7. Each entry must record only what the procedure requires, in the order the steps require it, with no added commentary.

ELL supports

Pre-teach recirculate, drain, permeate, differential pressure, and neutralization basin with a labeled sketch of the train, cleaning tank, and pump loop. Provide a bilingual glossary of shall, may, and shall not with one example sentence each. Allow items 2, 6, 7, and 10 to be answered with step numbers alone before students write the wording.

Extensions

Have students bring in a set of instructions they already follow outside school, such as a lab safety sheet or the directions for a piece of equipment, and mark every conditional sentence in it. Ask them to write one paragraph naming the condition a hurried reader is most likely to miss and what would happen as a result.