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Worksheet Grade 10 English Language Arts

Reading a Water-Testing Field Report: An Aquatic Chemistry Worksheet

A grade 10 worksheet where students read a technician's field report on pH, dissolved oxygen, and turbidity, then write an evidence-based judgment of water quality.

Objectives

  1. Students will locate specific data points in a technical field report.
  2. Students will apply a stated exception rule to new data to determine whether it applies.
  3. Students will use evidence from a field report to support a written judgment.

Vocabulary

Turbidity
Turbidity is a measure of how cloudy or murky water looks because of tiny particles floating in it. Clear water has low turbidity, and muddy water has high turbidity.
Dissolved oxygen
Dissolved oxygen is the oxygen gas mixed into water that fish and other underwater animals breathe. Cold, moving water holds more oxygen than warm, still water.
pH
pH is a number that tells whether water is acidic, like lemon juice, or basic, like baking soda mixed in water. Pure water sits in the middle of the scale at a pH of 7.

Also: field report

Teacher overview

A water quality technician's field report is a working document made up of short entries, exact numbers, and a note for whatever special case the technician might run into. This worksheet gives students a fictional field report from three sampling sites around Cobalt Reservoir, along with the real pH and dissolved-oxygen benchmarks a technician would compare those readings against, and asks students to read the data closely enough to apply the report's own exception rule and defend a judgment with evidence.

Reading a Water-Testing Field Report: An Aquatic Chemistry Worksheet — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Read this fictional field report from Cobalt Reservoir, then answer the questions that follow.

Cobalt Reservoir Water-Testing Field Report

  • Site A -- Inflow, 8:00 a.m.: pH 7.2, dissolved oxygen 6.8 mg/L, turbidity 4.1 NTU, temperature 18°C.
  • Site B -- Mid-reservoir, 8:20 a.m.: pH 7.6, dissolved oxygen 5.4 mg/L, turbidity 2.3 NTU, temperature 19°C.
  • Site C -- Near outflow, 8:45 a.m.: pH 8.9, dissolved oxygen 3.1 mg/L, turbidity 6.7 NTU, temperature 21°C.

Field notes:

  • The secondary (aesthetic) drinking-water standard for pH is 6.5 to 8.5. Most fish need dissolved oxygen above 5 mg/L to stay healthy, and cold water holds more oxygen than warm water.
  • Sites with heavy algae growth can show pH readings above 8.5 by mid-morning, since algae raise pH as they take in carbon dioxide during photosynthesis, and the same algae can cause sharp dissolved-oxygen drops after sunset as they respire.
  • Special case: if a site's dissolved-oxygen reading is below 4 mg/L, the technician must retest that site within 24 hours and flag it for the biologist's review, since a single low reading can result from a temporary condition rather than a lasting problem.
  1. Which site has the highest turbidity reading?
  2. Which site's pH falls outside the secondary standard range of 6.5 to 8.5?
  3. What is the special-case rule written into the field report for a low dissolved-oxygen reading?
  4. Does Site C trigger this special case? Explain using the numbers in the report.
  5. According to the field note on algae, why might Site C show both a high pH and a low dissolved-oxygen reading in the same report?
  6. Would Site C's water be more or less comfortable for fish than Site A's? Cite two numbers from the report to support your answer.
  7. Based on how it is used in this report, what does "turbidity" measure?
  8. Suppose a fourth site, Site D, records a dissolved-oxygen reading of 3.8 mg/L. Does it trigger the special-case retest rule? Explain.
  9. Write two sentences, in a style consistent with the report's other field notes, that a technician might add recommending an action based on Site C's readings.
  10. Between Site A and Site B, which is closer to the 4 mg/L retest threshold, and by how many mg/L?

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: Site C.
    Site C's turbidity reading of 6.7 NTU is higher than Site A's 4.1 NTU and Site B's 2.3 NTU.
  2. Answer: Site C.
    Site C's pH of 8.9 is above the secondary standard's upper bound of 8.5.
  3. Answer: Retest within 24 hours and flag the site for the biologist's review.
    The report states this rule directly for any reading below 4 mg/L dissolved oxygen.
  4. Answer: Yes.
    Site C's dissolved-oxygen reading of 3.1 mg/L is below the 4 mg/L threshold that triggers the special case.
  5. Answer: Heavy algae can raise pH through photosynthesis and lower dissolved oxygen through respiration, which matches Site C's high pH and low oxygen.
    The field note connects both effects to algae, and Site C's location near the outflow and warmer temperature (21°C) are consistent with more algae growth.
  6. Answer: Less comfortable.
    Site C's dissolved oxygen (3.1 mg/L) is well below the 5 mg/L most fish need, while Site A's (6.8 mg/L) is above it.
  7. Answer: The cloudiness of water caused by suspended particles.
    The report uses turbidity as a numeric reading (in NTU) at each site, consistent with a measure of water clarity.
  8. Answer: Yes.
    3.8 mg/L is below the 4 mg/L threshold, so Site D would trigger the same retest and biologist-review rule as Site C.
  9. Answer: Answers will vary. A strong response matches the report's terse style and recommends an action tied to Site C's low dissolved oxygen and high pH, such as: "Site C flagged for biologist review per dissolved-oxygen exception. Recommend algae check at next visit."
  10. Answer: 1.4 mg/L.
    Site B's dissolved oxygen (5.4 mg/L) is 1.4 mg/L above the 4 mg/L threshold, compared to Site A's 6.8 mg/L, which is 2.8 mg/L above it, so Site B is closer.

Differentiation

Support (below grade level)

Provide a highlighted copy of the field report with the dissolved-oxygen numbers in one color and the pH numbers in another, and let students answer items 4, 6, and 8 by circling the relevant numbers before writing a sentence.

Extension (above grade level)

Ask students to write a short paragraph proposing a fourth field note the report should include, based on a pattern they notice across all three sites, and to justify why that pattern is worth flagging for future testing.

ELL supports

Pre-teach "turbidity," "dissolved oxygen," "pH," and "field report" with simple definitions and a labeled diagram showing clear water (low turbidity) beside cloudy water (high turbidity). Allow items 5 and 9 to be answered with bullet points rather than full sentences.