Acid sensitive sites for forestry

MOSSAD

I had this thread posted on another forum, but had few comments. As there seems to be a number of foresters contributing to this forum, I'd be interested in hearing what people think.The following is a protocol which the Forest Service demands must be followed in order to assess the suitability of a site for afforestation. Four water samples must be taken between Februrary and May, at least a week apart. If the CaCo3 measures> 15mg/l, afforestation will be grant aided. If any one test falls below this, afforestation will in almost all cases be refused.

This sensitivity of the water to acidic inputs is determined by the measurement of alkalinity.
Sampling and analysis shall be carried out on a minimum of four occasions at intervals not greater
than four weeks in the period February to May inclusive. The analysis will be carried out by a
laboratory, independent of the applicant, and currently participating in relevant national or
international intercomparison exercises. Samples and measurements should be taken from all
watercourses shown on Ordnance Survey 6" Maps within the area of the proposed afforestation.
Samples should be taken as indicated in the procedure on page 137.
Alkalinity should be measured using the Gran Titration Method.
The minimum acid-sensitivity measured in the above manner will determine the overall sensitivity
of the site.
There will be no afforestation approved in areas where the minimum alkalinity of the run-off water,
measured in the above manner, is <8 mg CaCO

3 l-1.
Where the minimum alkalinity of the run-off water, measured in the above manner, is in the range
8 – 15 mg CaCO3 l-1, full, partial or no afforestation may be allowed following discussion and
agreement between the Environmental Protection Agency, the Forest Service of the Department of
the Marine and Natural Resources and the Regional Fisheries Board.
Afforestation will be allowed in areas where the minimum alkalinity of the run-off water, measured in the above manner, is >15 mg CaCO3 l-1.

Can this protocol be considered a correct interpretation of what might be happening on the site? I know of one site where three of the tests were, 20, 25 and 23 mg CaCO3/l and one was 10mg. The site was refused based on the low figure. Subesquent testing the next year gave four tests well above 15mg/l, but the site was refused based on the lowest result of the initial four tests.
Am I alone in thinking that this is a misuse/abuse of the sampling process? It should be borne in mind tha tup to 10% of the country has provisionally been sterilised based on this calssification of "acid-sensitive".

blue5000

All I can say is errors do happen in labs, dirty glassware, faulty chemicals delivered in, never mind human error. There probably is grounds for an appeal system.
But these water hardness/acidity tests are there for a very good reason, mainly to protect fish in salmonoid rivers. If water in rivers is too acidic, fish can't live in them.

MOSSAD

Agree with you but to my mind the statistical method seems wrong.
If the average CaCo3 is above the lowest measured, why choose the lowest as an indication of what is happening on the site?
Also the test has been constantly defended by referral to a dissertation written in 1991 I believe, by the guy responsible for introducing this test. All other reports and papers on the topic would appear to have been ignored.
I ran this protocol by someone who's a biomolecular physicist. Based on his knowledge of chemistry and his understanding of what the EPA was trying to do, he dismissed the test based on both the statistical method used and his belief that as Ireland was a maritime country, the effect of alkaline earth ions should be investigated( ie sodium and potassium ions deposited from sea water) as it would account for a significant input that must be deposited on the land, thereby counteracting acidity. In fact it's been suggested that the current test, apart from the misuse of statistics, is too broad and that a test called the sodium dominance test be used to categorize sensitive areas.
Unfortunately it appears that nothing is being done to look again at the current protocol.

blue5000

MOSSAD wrote: »

Also the test has been constantly defended by referral to a dissertation written in 1991 I believe, by the guy responsible for introducing this test. All other reports and papers on the topic would appear to have been ignored.
.

I think you might have hit the nail on the head here. It's not what you know it's who you know in this country still.:(

MOSSAD

Well then, how do we get it at least looked at again? Some of the dept apparatchiks are just awed by someone with letters after his name....might try to get the IFA to pull the finger out.