Wednesday, February 15, 2017

Well Survey – Bohoc Haiti

Protected Lejene well.
On 17 Jan. 2017 I performed a brief survey of 4 pump wells in the Bohoc area (8 miles east of Pignon), three along National Route 3 and one in the village of Caiman.  I collected water samples to measure nitrate with a LaMotte® Water TesTab® Kit which measures nitrate-NO3 in discrete categories (0, 5, 20, 40 mg/l) determined by color change.  I used 3M petrifilm to determine presence of fecal coliform (blue colonies are E. coli, red colonies with gas are other coliform).  Coordinates were taken with a handheld GPS.

Two of the wells were in protected blue and white buildings that are kept locked and managed by a well committee.  At both wells people drink the water without treating it, and also use it for washing and cooking.  One committee said they treat the well once a month with chlorine, and that people must take off their shoes before entering the building.  People at the Caiman well said they do not drink the water, but use it for cooking and washing.  At a second unprotected well, someone said that some people drink the well water but shouldn’t. 

Caiman well.
Surprisingly none of the wells showed E. coli, nor even other types of coliform, indicating that here is no contamination from fecal material.  Of concern is nitrate levels.  High nitrate in drinking water can cause methemoglobinemia (blue baby syndrome) in babies less than 6 months old as the nitrate depletes oxygen in the blood.  The USEPA maximum standard for nitrate-N in drinking water is 10 mg/l.  The WHO maximum standard for nitrate-NO3 in drinking water is 50 mg/l (or 11.3 mg/l nitrate-N).  Nitrate-NO3 values were multiplied by 0.2259 to convert to nitrate-N.  The two protected wells were below the nitrate limits, however the two unprotected wells had at least 9.04 mg/l nitrate-N (40 mg/l nitrate NO3), the maximum value that the LaMotte kit can report.  Therefore water from the two unprotected wells should not be given to babies < 6 months old until further tests can determine actual nitrate levels.

The results of this study were shared with the well committee and users, with cautions to those at the unprotected wells to avoid giving this water to babies.


1 comment:

  1. To remember for later! Multiply nitrate-NO3 by 1/4.42664 to get nitrate-N. Multiply nitrite-NO2 by 1/3.28443 to get nitrite-N. EPA usese the nitrogen form, WHO uses the entire molecule.
    https://www.hamzasreef.com/Contents/Calculators/NitrogenIonConversion.php

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