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Chloride
Load
West
Virginia's Office of Oil and Gas allows the landspraying of
liquid drill waste if it meets certain requirements covered
in the West
Virginia General Water Pollution Control Permit. The permit
as it exists today reached its final form in 1988. Documents
we examined at the West Virginia Department of Environmental
Protection offices, related to a FOIA request, had to do with
the creation and rationale for the permit which underwent
several major transformations after the first permit was instituted
in the mid-1980s. The state was sued by industry and made
changes. The state also stopped allowing discharge of liquid
drill waste directly into streams and rivers.
An
issue we have with the permit is the high level of chlorides
(salts) that are allowed to be sprayed out of the pit onto
forest or other "nonproductive" land. The state
has several categories of pit waste, the lowest chloride level
being up to 5,000 mg/l, the highest being 12,500 mg/l (with
a waiver allowed for up to 25,000 mg/l). The problem with
chlorides is that too great a quantity will kill vegetation
and we've heard of sites where landspraying has occurred in
this state when even large trees have been killed. Too great
a quantity of chlorides can sterilize soil, causing "salt
scaring" -- permanent areas with no vegetation at all.
Salt scaring is a feature of some older oil fields in other
states.
We've
been concerned about the levels of chlorides allowed, believing
that a maximum of 3,000 mg/l is much more realistic. The problem
is that there's another element -- the volume of pit liquids
and the area of land that is covered. We believe that chloride
load was considered for the permit in the 1980s but was dropped
for some reason.
Here's
a simple formula: (volume in barrels) X (chlorides mg/l) X
0.00035 = pounds of chlorides. A barrel is 42 gallons and
if we want the weight for 20,000 gallons of waste (476.19
barrels) at 3,000 mg/l it comes out to 500 pounds of chlorides.
To
figure the load divide the formula total by the number of
acres. Well permit applications we've seen set aside an area
of usually less than an acre for landspraying the liquid.
Figuring one acre, 20,000 gallons of 3,000 mg/l chlorides
is then 500 pounds of chlorides an acre.
Twenty
thousand gallons was a figure out of thin air. We've seen
a document
where the state's average landspraying involves 35,000 gallons.
That's 850 pounds of chlorides at 3,000 mg/l.
Oklahoma
in the early 1980s determined that the maximum chloride load,
per acre, should be 400 pounds. Saskatchewan
has a chloride load limit of 400 kg/ha (356 lbs per acre)
for landsprayed drill waste. 3,000 mg/l at 20,000 gallons
on one acre is already above that. Pits can have 5,000 mg/l
chlorides or 10,000 mg/l or up to 25,000 mg/l with a waiver.
And while the average landspraying can involve 35,000 gallons
we believe that it's not uncommon for wells to have pits with
a quarter million gallons or more of waste. Recently the state's
Office of Oil and Gas created a memorandum
on pits and is working on a draft
guidance document for those wells with high volume water
usage.
The
Berry Energy well had 100,000 gallons (or 2,381 barrels) of
waste. If, as according to the company's DMR, the chloride
concentration at discharge was 6,210 mg/l, then that means
5,175 pounds of chlorides were landsprayed. For two acres,
that is a load of 2,588 pounds (over a ton) per acre.
But,
in reality, 80,000 gallons was sprayed on about half an acre,
equal to 4,141 pounds of chlorides. That's 0.19 pounds (3
ounces) of salt per square foot. An unreasonable amount by
any standard (in Saskatchewan, that drill waste would have
had to been spread over at least 11.6 acres). There is reason
to doubt some of Berry's test results in their DMR and it
is possible that perhaps more than twice as much chlorides
was landsprayed in the Forest.
The
next chapter discusses the Sodium Adsorption Ratio (SAR).
Just as the state has no load for chlorides, it has no program
to manage the high sodium concentrations in drill waste.
Go
to the SAR chapter.
We
have a page about the environmental
effects of chloride.
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