NJ S1 wastewater exam WITH VERIFIED
AND DETAILED ANSWERS 2026 LATEST
EDITION
What is the main purpose of a trickling filter? - ANSWER☑️⭐-To oxidize organic material
What is a typically acceptable D.O. in an aerobic digester? - ANSWER☑️⭐-0.5 to 1.5 mg/l
Which chemical is used to identify a chlorine leak? - ANSWER☑️⭐-Ammonia
When using the proper chemical to identify a chlorine leak, what color will the cloud of smoke be? -
ANSWER☑️⭐-White
Why is flooding of trickling filter media sometimes recommended? - ANSWER☑️⭐-To control filter flies
What is a common method of determining the quantity of chlorine used each day? - ANSWER☑️⭐-Read
the chlorine scale weight
What is the principle concept of the gravity belt thickener? - ANSWER☑️⭐-Thickens through gravity
drainage
What is the percent BOD5 removal efficiency in this plant?
Influent CBOD5 is 250 mg/l
, Effluent CBOD5 is 3.5 mg/l - ANSWER☑️⭐-98.6%
In - out / in * 100
250 - 3. * 100 = 98.6
What is the RAS flow rate, in mgd, in this activated sludge process?
• Influent Flow is 575,000 gpd
• RAS rate is 55% of Q - ANSWER☑️⭐-0.316mgd
Q(mgd) * RAS% of Q
575,000gpd = .575 mgd
.575 * .55 = .316
TSS - ANSWER☑️⭐-Total Suspended Solids
What is the percent TSS removal efficiency in this plant?
• Influent TSS is 200 mg/l
• Effluent TSS is 2.5 mg/l - ANSWER☑️⭐-98.8%
200 - 2.5 = 197.5/200 * 100 = 98.8
What piece of equipment is used in the volatile solids test? - ANSWER☑️⭐-muffle furnace for burning,
desiccator for cooling and moisture control, and analytical balance for weighing.
What is the detention time in the aeration tank? (not including RAS flow)
• Influent Flow is 575,000 gpd
• Aeration Tank Dimensions are 100 ft. Long, 25 ft. Wide, and 14 ft. Deep - ANSWER☑️⭐-10.93hrs
Detention Time, hrs = V/Q
V= 100 * 25 * 14 * 7.48 = 261,800/1,000,000 = .2618mg
575,000/1,000,000 = .576 mg
0.2618 mg tank volume ÷ 0.575 mgd Inf Flow x 24 hrs/day
= 10.93 hours
AND DETAILED ANSWERS 2026 LATEST
EDITION
What is the main purpose of a trickling filter? - ANSWER☑️⭐-To oxidize organic material
What is a typically acceptable D.O. in an aerobic digester? - ANSWER☑️⭐-0.5 to 1.5 mg/l
Which chemical is used to identify a chlorine leak? - ANSWER☑️⭐-Ammonia
When using the proper chemical to identify a chlorine leak, what color will the cloud of smoke be? -
ANSWER☑️⭐-White
Why is flooding of trickling filter media sometimes recommended? - ANSWER☑️⭐-To control filter flies
What is a common method of determining the quantity of chlorine used each day? - ANSWER☑️⭐-Read
the chlorine scale weight
What is the principle concept of the gravity belt thickener? - ANSWER☑️⭐-Thickens through gravity
drainage
What is the percent BOD5 removal efficiency in this plant?
Influent CBOD5 is 250 mg/l
, Effluent CBOD5 is 3.5 mg/l - ANSWER☑️⭐-98.6%
In - out / in * 100
250 - 3. * 100 = 98.6
What is the RAS flow rate, in mgd, in this activated sludge process?
• Influent Flow is 575,000 gpd
• RAS rate is 55% of Q - ANSWER☑️⭐-0.316mgd
Q(mgd) * RAS% of Q
575,000gpd = .575 mgd
.575 * .55 = .316
TSS - ANSWER☑️⭐-Total Suspended Solids
What is the percent TSS removal efficiency in this plant?
• Influent TSS is 200 mg/l
• Effluent TSS is 2.5 mg/l - ANSWER☑️⭐-98.8%
200 - 2.5 = 197.5/200 * 100 = 98.8
What piece of equipment is used in the volatile solids test? - ANSWER☑️⭐-muffle furnace for burning,
desiccator for cooling and moisture control, and analytical balance for weighing.
What is the detention time in the aeration tank? (not including RAS flow)
• Influent Flow is 575,000 gpd
• Aeration Tank Dimensions are 100 ft. Long, 25 ft. Wide, and 14 ft. Deep - ANSWER☑️⭐-10.93hrs
Detention Time, hrs = V/Q
V= 100 * 25 * 14 * 7.48 = 261,800/1,000,000 = .2618mg
575,000/1,000,000 = .576 mg
0.2618 mg tank volume ÷ 0.575 mgd Inf Flow x 24 hrs/day
= 10.93 hours
