scoops

Tuesday, July 5, 2016

How safe is sludge?

The Texas Administrative Code (TAC) addresses “Pathogen Reduction” in sludge with the following restrictions. That should tell you something about how “safe” sludge is:

(3) Site restrictions.

(A) Food crops with harvested parts totally above the land surface that touch the sewage sludge/soil mixture must not be harvested from the land for at least 14 months after the application of sewage sludge.

(B) Food crops with harvested parts below the surface of the land must not be harvested for at least 20 months after application of sewage sludge when the sewage sludge remains on the land surface for four months or longer prior to incorporation into the soil.

(C) Food crops with harvested parts below the surface of the land must not be harvested for at least 38 months after application of sewage sludge when the sewage sludge remains on the land surface for less than four months prior to the incorporation into the soil.

(D) Food crops, feed crops, and fiber crops must not be harvested for at least 30 days after application of sewage sludge.

(E) Animals must not be allowed to graze on the land for at least 30 days after application of sewage sludge.

(F) Turf grown on land where sewage sludge is applied may not be harvested for at least one year after application of sewage sludge when the harvested turf is placed on either land with a high potential for public exposure or a lawn.

(G) Public access to land with a high potential for public exposure must be restricted for at least one year after application of sewage sludge.

(H) Public access to land with a low potential for public exposure must be restricted for at least 30 days after application of the sewage sludge.

Texas Administrative Code
TITLE 30 ENVIRONMENTAL QUALITY
PART 1 TEXAS COMMISSION ON ENVIRONMENTAL QUALITY
CHAPTER 312 SLUDGE USE, DISPOSAL, AND TRANSPORTATION
SUBCHAPTER D PATHOGEN AND VECTOR ATTRACTION REDUCTION
RULE ยง312.82 Pathogen Reduction

Download PDF

But even the supposedly “safe” sludge - Dillo Dirt - that you can buy at Home Deport is not so safe. You may remember that before the Austin City Limits Music Festival in 2009, Dillo Dirt was applied to the Zilker Park turf. When it rained and the turf turned to muck, the pathogens in the sludge sickened a number of people. This was not Austin’s finest hour thanks to a substance that is potentially very dangerous. You can read about that fiasco here.

Unfortunately pathogens are not the only danger lurking in sewage sludge. There are other contaminants in sludge from household use AND industrial waste AND agricultural/road runoff etc. that may include - heavy metals, synthetic chemicals & pesticides, hydrocarbons, petrochemicals, organochlorines, pharmaceuticals, steroids & hormones etc. Monitoring of these substances is limited. Regulatory ‘truth’ once again in denial of reality.