| C |
measured concentration of radioactive tracer (Radioactivity L-3) |
| co |
initial concentration of radioactive tracer (Radioactivity L-3) |
| c1 |
concentration of conservative tracer in end-member water 1 (Radioactivity L-3) or (ML-3) |
| c2 |
concentration of conservative tracer in end-member water 2 (Radioactivity L-3) or (ML-3) |
| cAi |
concentration of tracer A in end-member water n (Radioactivity L-3) or (ML-3) |
| cAm |
concentration of tracer A in mixture (Radioactivity L-3) or (ML-3) |
| cd |
daughter concentration (Radioactivity L-3) |
| Ca |
concentration in dry air (ML-3) |
| cm |
concentration in the mixed water (ML-3) |
| cp |
parent concentration (Radioactivity L-3) |
| Cw |
concentration dissolved in water (ML-3) |
| D |
diffusion coefficient of the tracer (L2T–1) |
| δ |
isotope ratio relative to a standard (dimensionless) |
| f |
proportion of end-member 1 in the mixture (dimensionless) |
| 1 – f |
proportion of end-member 2 in the mixture (dimensionless) |
| fn |
proportion of end-member ‘n’ (dimensionless) |
| H |
thickness (L) |
| KH |
Henry’s Law constant (dimensionless) |
| λ |
decay constant (T–1) |
| vh |
horizontal groundwater velocity (LT–1) |
| P |
total atmospheric pressure (ML–1T–2) |
| pH2O |
water vapor pressure (ML–1T–2) |
| R |
in Equation 4, ratio of isotope amount, usually less abundant to most abundant isotope (dimensionless) |
| R |
in Equation 10, constant recharge (LT–1) |
| R |
in Equation 13, recharge rate (LT–1) |
| t |
in Equation 1, time (T) |
| t |
in Equation 10, groundwater age (T) |
| t1 and t2 |
groundwater ages at two points in the confined part of the aquifer (T) |
| θ |
porosity (dimensionless) |
| t1/2 |
half-life of radioactive tracer (T) |
| tmix |
extent of well mixing (measured in years) (T) |
| x |
distance (L) |
| x2 – x1 |
distance between locations (L) |
| z |
depth below the water table (L) |
| zwell |
length of the well intake zone (L) |
