Parameter | Symbol | Unit | Distribution | Note(s) |
---|---|---|---|---|

Concn | ||||

Fecal Streptococcus | ||||

IEC | Cs | MPN/100 ml | Normal (mean = 2,988, SD = 785) | Distribution of mean determined using central limit theorem because n > 30 |

Saybrook | CFU/100 ml | Distribution of mean could not be determined because n = 2 | ||

Enterococcus | ||||

IEC | Ce | MPN/100 ml | Normal (mean = 2,762, SD = 784) | Distribution of mean determined using central limit theorem because n > 30 |

Saybrook | CFU/100 ml | Distribution of mean could not be determined because n = 2 | ||

Giardia | ||||

Saybrook, CSO | Cg | Cysts/ml | Distribution of mean could not be determined because n = 1 | |

Saybrook, downstream of CSO | Distribution of mean could not be determined because n = 1 | |||

Giardia | rg | No unit | Empirical (2.5th = 0.009798; 12.5th = 0.01336; 25th = 0.01584; 50th = 0.0198; 75th = 0.02466; 87.5th = 0.02845; 97.5th = 0.03582) | Rose et al. (26); calculated based on likelihood confidence intervals |

Water ingestion | IR_{hourly} | ml/h | ||

Recreator | 50 ml/h; incidental ingestion rate during swimming | |||

Visitor | 10 ml/h; adults/adolescents—surface water during wading | |||

Homeless person | 50 ml/h; incidental ingestion rate during swimming | |||

Time spent outdoors at river | T | Minutes/day | Empirical (5th = 20; 25th = 60; 50th = 150; 75th = 320; 90th = 511; 95th = 615) | USEPA, 1997, Table 15-110 (31) |

Fraction of time at river spent in water | F | % | ||

Recreator | Assumed 20% | |||

Visitor | Assumed 20% | |||

Homeless person | Assumed 40% | |||

Incidental water ingestion rate implicit in AWQC^{a} dose-response relationship, swimming | IR_{AWQC} | ml/day | Triangular (minimum = 10; mode = 16; maximum = 100) | Ingestion rate used to account for uncertainty in incidental ingestion of water inherent in AWQC dose-response equation for incidental ingestion of water during swimming (Dufour et al., 2006 [4]) |

Incidental water ingestion rate | IR_{daily} | ml/day | IR_{daily} = IR_{hourly} × F × (T/60) | |

Recreator | Calculated | |||

Visitor | Calculated | |||

Homeless person | Calculated | |||

Exposure frequency | EF | Days/yr | Triangular | Maximum no. of days limited by |

Recreator | Minimum = 1, mode = 12, maximum = 95 | meteorological factors such as | ||

Visitor | Minimum = 1, mode = 2, maximum = 12 | precipitation and temp | ||

Homeless person | Minimum = 1, mode = 24, maximum = 150 |

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*a*AWQC, ambient water quality criteria.