Hoot Field Results: 20 Systems, 100 Lab Tests
Field results from Hoot systems in service around Placer County, 2007–2011.
Between 2007 and 2011, Superior On-Site Solutions collected effluent samples from Hoot advanced treatment systems at 20 homes in Placer County, California, during routine service visits about every six months. Each sample was sent to a lab for analysis. The results below include every sample, including the occasional high reading.
What the results show
- Clean, clear effluent. The median CBOD was 3.2 mg/L, compared with 150–250 mg/L in typical septic tank effluent. Half of all TSS samples had no measurable solids.
- Most high readings came early. Many readings above 30 mg/L were a site’s first or second sample, while the system was still establishing. Results typically settled well below the standard afterward.
- Near-complete nitrification. The median TKN (organic plus ammonia nitrogen) was 2.1 mg/L, compared with 26–75 mg/L in typical household wastewater (U.S. EPA). Low TKN shows the aerobic process is converting ammonia; nitrate was not measured in this program.
- Bacteria. The median fecal coliform result was about 9 MPN/100 mL. Most of these systems did not have disinfection installed; where a county requires pathogen treatment, a UV disinfection unit is added.
Results by site
Median of all samples at each site, with the highest reading in parentheses (mg/L; fecal coliform in MPN/100 mL). “Met 30/30” = samples with both CBOD and TSS at or below 30 mg/L. ND = not detected.
| Site | System | Samples | CBOD | TSS | TKN | Fecal | Met 30/30 |
|---|---|---|---|---|---|---|---|
| 1 · Meadow Vista | H600, 2006 | 6 ’07–’08 | 14 (79) | 22 (53) | 56 | 450 (≥1,600) | 4 of 6 |
| 2 · Newcastle | H600, 2005 | 5 ’07–’11 | ND (49) | 10 (40) | 3.1 | ND (170) | 3 of 5 |
| 3 · Auburn | Hoot system | 5 ’07–’09 | 9.3 (59) | 14 (57) | 6.4 | 465 (≥1,600) | 3 of 5 |
| 4 · Meadow Vista | Hoot system | 5 ’07–’09 | 6.7 (12) | 11 (31) | 5.8 | 175 (430) | 4 of 5 |
| 5 · Colfax | H600, 2006 | 5 ’07–’09 | ND (17) | ND (10) | 3.2 | 21 (110) | 5 of 5 |
| 6 · Sheridan | H600, 2007 | 5 ’07–’09 | 11 (32) | 18 (85) | 4.3 | 940 (≥1,600) | 2 of 5 |
| 7 · Lincoln | Hoot system | 5 ’07–’09 | 6.1 (60) | ND (5.7) | 11 | 1.0 (4.0) | 4 of 5 |
| 8 · Sheridan | Hoot system | 5 ’07–’10 | ND (14) | 13 (66) | 0.2 | 4.5 (220) | 4 of 5 |
| 9 · Penryn | H600, 2007 | 5 ’07–’09 | ND (2.2) | ND (ND) | 1.1 | 13 (540) | 5 of 5 |
| 10 · Auburn | H600 two-chamber, 2008 | 5 ’08–’10 | 4.2 (65) | 9.7 (38) | 23 | 72 (≥1,600) | 4 of 5 |
| 11 · Lincoln | H750, 2008 | 5 ’08–’10 | ND (22) | ND (12) | ND | 1.6 (13) | 5 of 5 |
| 12 · Colfax | Hoot system, 2007 | 5 ’08–’10 | 4.0 (38) | ND (58) | 2.7 | 885 (≥1,600) | 4 of 5 |
| 13 · Colfax | H600, 2007 | 5 ’08–’10 | 3.0 (10) | 5.0 (6.5) | 0.7 | 240 (≥1,600) | 5 of 5 |
| 14 · Loomis | Hoot system | 5 ’08–’10 | 4.1 (5.3) | ND (120) | 1.7 | 483 (≥1,600) | 4 of 5 |
| 15 · Applegate | H600, 2007 | 5 ’08–’10 | 4.7 (6.6) | ND (ND) | ND | 3.2 (20) | 5 of 5 |
| 16 · Auburn | Hoot system | 5 ’08–’10 | ND (36) | 1.7 (45) | 1.4 | 1.8 (27) | 3 of 5 |
| 17 · Newcastle | H600, 2007 | 5 ’08–’10 | 3.1 (6.2) | ND (5.0) | 2.2 | 2.0 (350) | 5 of 5 |
| 18 · Colfax | H600, 2008 | 5 ’09–’11 | 1.9 (16) | ND (18) | 3.6 | 33 (≥1,600) | 4 of 4 |
| 19 · Loomis | H600, 2008 | 5 ’09–’11 | ND (5.4) | 5.6 (17) | 1.2 | 9.3 (23) | 5 of 5 |
| 20 · Applegate | H600, 2007 | 4 ’09–’11 | ND (6.2) | ND (7.6) | 1.0 | 1.8 (1.8) | 4 of 4 |
Source: SOS water sampling log dated March 21, 2011. Sites are identified by town only to protect homeowner privacy. Three sites with incomplete records are not shown. Fecal coliform method upper limit is 1,600 MPN/100 mL.