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Worksheet Grade 12 English Language Arts

Annotating Larkspur Water Authority's Reuse Feasibility Memo

A grade 12 worksheet where students read a technical water-reuse feasibility memo and rewrite its key findings as plain-language FAQ entries for a public meeting.

Objectives

  1. Students will extract key technical findings from an engineering feasibility memo.
  2. Students will distinguish technical register from plain language and translate between the two.
  3. Students will reorganize technical content into a public-facing informative format.

Vocabulary

Indirect potable reuse
Recycling water into drinking water with a natural stop along the way. Highly cleaned water is put into the ground or a reservoir, then drawn back out later and treated again for drinking.

Also: feasibility memo, environmental buffer, technical register

Teacher overview

Engineering feasibility memos are written for a board that already knows the technical vocabulary, which means the same information almost always needs a second, plain-language version before it can be shared with the public at a meeting. This worksheet gives students a feasibility memo from Larkspur Water Authority, a fictional utility considering a water-reuse facility, and asks them to extract its key findings and then reorganize those findings into the kind of FAQ handout a real public meeting would use.

Annotating Larkspur Water Authority's Reuse Feasibility Memo — Grade 12 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Larkspur is a fictional utility used for this worksheet. Read the memo below, then answer the questions that follow.

MEMORANDUM — To: Larkspur Water Authority Board. From: Engineering Division. Re: Feasibility of an Indirect Potable Reuse Facility.

Larkspur's reservoir supply has declined in each of the past several dry years, and the board has asked engineering to evaluate indirect potable reuse as a new supply source. Indirect potable reuse treats wastewater to a very high standard and returns it to a groundwater basin or reservoir, where it serves as what regulators call an environmental buffer, additional storage and mixing time, before the water is withdrawn again for treatment and distribution. Orange County's Groundwater Replenishment System is the world's largest facility of this kind, treating and returning water to its groundwater basin at a capacity of 130 million gallons per day, and it offers a proven model for a project at Larkspur's scale.

The core purification step in a reuse facility is reverse osmosis membrane treatment, which by engineering's estimate for Larkspur requires roughly 3 to 4 kilowatt-hours of energy per 1,000 gallons treated, compared with about 1 to 2 kilowatt-hours for conventional treatment. This energy cost is the primary tradeoff the board must weigh against the cost and reliability risk of continuing to rely solely on a shrinking reservoir supply. Benefits include a drought-resistant supply that does not depend on rainfall and reduced discharge of treated wastewater into the river. The main drawbacks are the higher energy cost and the public education effort required before residents accept reused water flowing from their taps. Engineering recommends the board authorize a smaller pilot study before committing to full-scale design.

  1. According to the memo, what problem is prompting Larkspur to consider a reuse facility?
  2. What real-world facility does the memo cite as a precedent, and how large is it?
  3. According to the memo, how much more energy does the reverse osmosis stage require compared to conventional treatment?
  4. In your own words, explain what "indirect potable reuse" means, based on the memo's definition.
  5. The memo uses the phrase "environmental buffer." Define it using context from the memo.
  6. Choose one sentence from the memo written in technical, board-facing register, and rewrite it in plain language.
  7. List two benefits and one drawback of reuse that the memo presents.
  8. Write two FAQ-style questions and answers, in plain language, that Larkspur could hand out at a public meeting, using information from the memo.
  9. Why might a memo written for the utility board use more technical language than a public-facing FAQ on the same topic? Support your answer with one specific detail from the memo.
  10. Based on the memo, what is one piece of information Larkspur's board would likely need before approving the project that the memo does not provide?

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: Larkspur's reservoir supply has declined in each of the past several dry years, prompting the board to look for an additional, more drought-resistant supply source.
  2. Answer: Orange County's Groundwater Replenishment System, the world's largest indirect potable reuse facility, with a capacity of 130 million gallons per day.
  3. Answer: Reverse osmosis requires roughly 3 to 4 kilowatt-hours per 1,000 gallons, compared with about 1 to 2 kilowatt-hours for conventional treatment, meaning it uses roughly two to three times more energy.
  4. Answer: Answers will vary; a strong response explains that treated wastewater is returned to a groundwater basin or reservoir and stored there before being withdrawn and treated again for drinking water, rather than being piped directly back to taps.
  5. Answer: The environmental buffer is the additional storage and mixing time the water spends in the groundwater basin or reservoir between advanced treatment and eventual withdrawal for drinking water.
  6. Answer: Answers will vary; a strong rewrite trades technical terms for plain equivalents, for example turning "the core purification step... requires roughly 3 to 4 kilowatt-hours of energy per 1,000 gallons treated" into "the main cleaning step uses a fair amount of electricity, but it makes the water safe to store and reuse."
  7. Answer: Benefits: a drought-resistant supply that does not depend on rainfall, and reduced wastewater discharge into the river. Drawback: the higher energy cost of the reverse osmosis step (and the public education challenge the memo also names).
  8. Answer: Answers will vary. A strong response includes genuine questions a resident might ask (for example, "Is this the same as drinking treated sewage directly?") answered in plain, accurate language drawn from the memo (for example, explaining the groundwater buffer step).
  9. Answer: Answers will vary but should reference that a board memo can assume readers already understand terms like "reverse osmosis" and "environmental buffer," while a public FAQ has to define or replace those terms, as shown by the memo's use of precise energy figures without further explanation.
  10. Answer: Answers will vary; reasonable responses include the project's estimated cost, an expected timeline, or public opinion data, none of which the memo provides.

Differentiation

Support

Provide a two-column glossary connecting each technical term in the memo (indirect potable reuse, environmental buffer, reverse osmosis) to a one-sentence plain-language definition before students begin item 4.

Extension

Ask students to draft a one-paragraph rebuttal a skeptical resident might submit to the board, raising a concern the memo does not address (such as taste, cost passed on to ratepayers, or public trust), and then write the engineering division's plain-language response.

ELL supports

Pre-teach "feasibility," "reuse," and "buffer" with a simple diagram showing water moving from wastewater treatment to the groundwater basin and back to the tap. Allow items 1, 2, and 3 to be answered with short phrases rather than full sentences.